<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Jung, Seokwon</style></author><author><style face="normal" font="default" size="100%">Chen, Yanfeng</style></author><author><style face="normal" font="default" size="100%">Sullards, M Cameron</style></author><author><style face="normal" font="default" size="100%">Ragauskas, Arthur J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Direct analysis of cellulose in poplar stem by matrix-assisted laser desorption/ionization imaging mass spectrometry.</style></title><secondary-title><style face="normal" font="default" size="100%">Rapid communications in mass spectrometry : RCM</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Rapid Commun. Mass Spectrom.</style></alt-title><short-title><style face="normal" font="default" size="100%">Rapid Commun Mass Spectrom</style></short-title></titles><dates><year><style  face="normal" font="default" size="100%">2010</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2010 Nov 30</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://dx.doi.org/10.1002/rcm.4757</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">24</style></volume><pages><style face="normal" font="default" size="100%">3230-6</style></pages><abstract><style face="normal" font="default" size="100%">Matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) was applied to the analysis of the spatial distribution of cellulose on a cross-section of juvenile poplar (Populus deltoids) stems. Microcrystalline cellulose (MCC) was used to optimize matrix (2,5-dihydroxybenzoic acid) application and instrument parameters for the detection of low hexose oligomers, which originated from cellulose in the solid phase. A section of poplar cellulose isolated from juvenile poplar stem which consisted primarily of glucose (∼95%) and minor components such as xylose and lignin was used for the MALDI-IMS studies. The mass spectrum of poplar cellulose consisted of a series of evenly spaced signals having a difference of 162  m/z units, which was similar to that of MCC in linear and reflectron positive ion modes. MS images of cellulose compounds with sodium ion adducts were generated and illustrated the distribution of cellulose on the surface of the poplar stem.</style></abstract><issue><style face="normal" font="default" size="100%">22</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20972996?dopt=Abstract</style></custom1><custom3><style face="normal" font="default" size="100%">20972996</style></custom3><custom4><style face="normal" font="default" size="100%">2010-11-30 12:00:00</style></custom4></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Furian, T C</style></author><author><style face="normal" font="default" size="100%">Hansel, J</style></author><author><style face="normal" font="default" size="100%">Nagenrauft, S</style></author><author><style face="normal" font="default" size="100%">Niess, A M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Collapse of a competitive athlete at a competition - Case 1/2010. Myocarditis].</style></title><secondary-title><style face="normal" font="default" size="100%">Deutsche medizinische Wochenschrift (1946)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Dtsch. Med. Wochenschr.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2010</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2010 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">135</style></volume><pages><style face="normal" font="default" size="100%">79</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099382?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gardner, Edward M</style></author><author><style face="normal" font="default" size="100%">Hullsiek, Katherine H</style></author><author><style face="normal" font="default" size="100%">Telzak, Edward E</style></author><author><style face="normal" font="default" size="100%">Sharma, Shweta</style></author><author><style face="normal" font="default" size="100%">Peng, Grace</style></author><author><style face="normal" font="default" size="100%">Burman, William J</style></author><author><style face="normal" font="default" size="100%">MacArthur, Rodger D</style></author><author><style face="normal" font="default" size="100%">Chesney, Margaret</style></author><author><style face="normal" font="default" size="100%">Friedland, Gerald</style></author><author><style face="normal" font="default" size="100%">Mannheimer, Sharon B</style></author></authors><translated-authors><author><style face="normal" font="default" size="100%">Terry Beirn Community Programs for Clinical Research on AIDS and the International Network for Strategic Initiatives in Global H</style></author></translated-authors></contributors><titles><title><style face="normal" font="default" size="100%">Antiretroviral medication adherence and class- specific resistance in a large prospective clinical trial.</style></title><secondary-title><style face="normal" font="default" size="100%">AIDS (London, England)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">AIDS</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2010</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2010 Jan 28</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">24</style></volume><pages><style face="normal" font="default" size="100%">395-403</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">To assess the association between adherence to antiretroviral therapy and the presence of class-specific antiretroviral medication resistance.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099399?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Alberg, Anthony J</style></author><author><style face="normal" font="default" size="100%">Hébert, James R</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Cigarette smoking and bladder cancer: a new twist in an old saga?</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of the National Cancer Institute</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Natl. Cancer Inst.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2010</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2010 Jan 20</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">102</style></volume><pages><style face="normal" font="default" size="100%">138</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099381?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhang, Keman</style></author><author><style face="normal" font="default" size="100%">Sha, Jingfeng</style></author><author><style face="normal" font="default" size="100%">Harter, Marian L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Activation of Cdc6 by MyoD is associated with the   expansion of quiescent myogenic satellite cells.</style></title><secondary-title><style face="normal" font="default" size="100%">The Journal of experimental medicine</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Exp. Med.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2010</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2010 Jan 18</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">207</style></volume><pages><style face="normal" font="default" size="100%">39-48, S1-2</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">MyoD is a transcriptional factor that is required for the differentiation of muscle stem cells (satellite cells). In this study, we describe a previously unknown function for MyoD in regulating a gene (Cdc6) that is vital to endowing chromatin with the capability of replicating DNA. In C2C12 and primary mouse myoblasts, we show that MyoD can occupy an E-box within the promoter of Cdc6 and that this association, along with E2F3a, is required for its activity. MyoD and Cdc6 are both expressed after quiescent C2C12 myoblasts or satellite cells in association with myofibers are stimulated for growth, but MyoD appears at least 2-3 h earlier than Cdc6. Finally, knockdown of MyoD impairs the ability of C2C12 cells to express Cdc6 after leaving quiescence, and as a result, they cannot fully progress into S phase. Our results define a mechanism by which MyoD helps myogenic satellite cells to enter into the first round of DNA replication after transitioning out of quiescence.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099377?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Xu, Yunling</style></author><author><style face="normal" font="default" size="100%">Yuan, Li</style></author><author><style face="normal" font="default" size="100%">Mak, Judy</style></author><author><style face="normal" font="default" size="100%">Pardanaud, Luc</style></author><author><style face="normal" font="default" size="100%">Caunt, Maresa</style></author><author><style face="normal" font="default" size="100%">Kasman, Ian</style></author><author><style face="normal" font="default" size="100%">Larrivée, Bruno</style></author><author><style face="normal" font="default" size="100%">del Toro, Raquel</style></author><author><style face="normal" font="default" size="100%">Suchting, Steven</style></author><author><style face="normal" font="default" size="100%">Medvinsky, Alexander</style></author><author><style face="normal" font="default" size="100%">Silva, Jillian</style></author><author><style face="normal" font="default" size="100%">Yang, Jian</style></author><author><style face="normal" font="default" size="100%">Thomas, Jean-Léon</style></author><author><style face="normal" font="default" size="100%">Koch, Alexander W</style></author><author><style face="normal" font="default" size="100%">Alitalo, Kari</style></author><author><style face="normal" font="default" size="100%">Eichmann, Anne</style></author><author><style face="normal" font="default" size="100%">Bagri, Anil</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Neuropilin-2 mediates VEGF-C-induced lymphatic sprouting together with VEGFR3.</style></title><secondary-title><style face="normal" font="default" size="100%">The Journal of experimental medicine</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Exp. Med.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2010</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2010 Jan 18</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">207</style></volume><pages><style face="normal" font="default" size="100%">115-30, S1-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Vascular sprouting is a key process-driving development of the vascular system. In this study, we show that neuropilin-2 (Nrp2), a transmembrane receptor for the lymphangiogenic vascular endothelial growth factor C (VEGF-C), plays an important role in lymphatic vessel sprouting. Blocking VEGF-C binding to Nrp2 using antibodies specifically inhibits sprouting of developing lymphatic endothelial tip cells in vivo. In vitro analyses show that Nrp2 modulates lymphatic endothelial tip cell extension and prevents tip cell stalling and retraction during vascular sprout formation. Genetic deletion of Nrp2 reproduces the sprouting defects seen after antibody treatment. To investigate whether this defect depends on Nrp2 interaction with VEGF receptor 2 (VEGFR2) and/or 3, we intercrossed heterozygous mice lacking one allele of these receptors. Double-heterozygous nrp2vegfr2 mice develop normally without detectable lymphatic sprouting defects. In contrast, double-heterozygote nrp2vegfr3 mice show a reduction of lymphatic vessel sprouting and decreased lymph vessel branching in adult organs. Thus, interaction between Nrp2 and VEGFR3 mediates proper lymphatic vessel sprouting in response to VEGF-C.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099375?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">van Ree, Janine H</style></author><author><style face="normal" font="default" size="100%">Jeganathan, Karthik B</style></author><author><style face="normal" font="default" size="100%">Malureanu, Liviu</style></author><author><style face="normal" font="default" size="100%">van Deursen, Jan M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Overexpression of the E2 ubiquitin-conjugating   enzyme UbcH10 causes chromosome   missegregation and tumor formation.</style></title><secondary-title><style face="normal" font="default" size="100%">The Journal of experimental medicine</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Exp. Med.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2010</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2010 Jan 18</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">207</style></volume><pages><style face="normal" font="default" size="100%">83-100, S1-4</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The anaphase-promoting complex/cyclosome (APC/C) E3 ubiquitin ligase functions with the E2 ubiquitin-conjugating enzyme UbcH10 in the orderly progression through mitosis by marking key mitotic regulators for destruction by the 26-S proteasome. UbcH10 is overexpressed in many human cancer types and is associated with tumor progression. However, whether UbcH10 overexpression causes tumor formation is unknown. To address this central question and to define the molecular and cellular consequences of UbcH10 overexpression, we generated a series of transgenic mice in which UbcH10 was overexpressed in graded fashion. In this study, we show that UbcH10 overexpression leads to precocious degradation of cyclin B by the APC/C, supernumerary centrioles, lagging chromosomes, and aneuploidy. Importantly, we find that UbcH10 transgenic mice are prone to carcinogen-induced lung tumors and a broad spectrum of spontaneous tumors. Our results identify UbcH10 as a prominent protooncogene that causes whole chromosome instability and tumor formation over a wide gradient of overexpression levels.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099376?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Friedl, Peter</style></author><author><style face="normal" font="default" size="100%">Wolf, Katarina</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Plasticity of cell migration: a multiscale tuning model.</style></title><secondary-title><style face="normal" font="default" size="100%">The Journal of experimental medicine</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Exp. Med.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2010</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2010 Jan 18</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">207</style></volume><pages><style face="normal" font="default" size="100%">11-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Cell migration underlies tissue formation, maintenance, and regeneration as well as pathological conditions such as cancer invasion. Structural and molecular determinants of both tissue environment and cell behavior define whether cells migrate individually (through amoeboid or mesenchymal modes) or collectively. Using a multiparameter tuning model, we describe how dimension, density, stiffness, and orientation of the extracellular matrix together with cell determinants--including cell-cell and cell-matrix adhesion, cytoskeletal polarity and stiffness, and pericellular proteolysis--interdependently control migration mode and efficiency. Motile cells integrate variable inputs to adjust interactions among themselves and with the matrix to dictate the migration mode. The tuning model provides a matrix of parameters that control cell movement as an adaptive and interconvertible process with relevance to different physiological and pathological contexts.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19951899?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ai, Jun</style></author><author><style face="normal" font="default" size="100%">Tschirner, Ulrike</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Fiber length and pulping characteristics of switchgrass, alfalfa stems, hybrid poplar and willow biomasses.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioresource technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bioresour. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2010</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2010 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">101</style></volume><pages><style face="normal" font="default" size="100%">215-21</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Switchgrass (Panicum virgatum), alfalfa stems (Medicago sativa), second year growth hybrid poplar (Populus) and willow (Salix spp.) were examined to determine fiber characteristics, pulping behavior and paper properties. Alfalfa stems and switchgrass both showed length weighted average fiber length (LWW) of 0.78 mm, a very narrow fiber length distribution and high fines content. Willow and hybrid poplar have lower fines content but a very low average fiber length (0.42 and 0.48 mm LWW). In addition, the four biomass species showed distinctly different chemical compositions. Switchgrass was defibered successfully using Soda and Soda Anthraquinone (AQ) pulping and demonstrated good paper properties. Both fast-growing wood species pulped well using the Kraft process, and showed acceptable tensile strength, but low tear strength. Alfalfa stems reacted very poorly to Soda and Soda AQ pulping but responded well to Kraft and Kraft AQ. Pulps with tensile and tear strength considerably higher than those found for commercial aspen pulps were observed for alfalfa. All four biomass species examined demonstrated low pulp yield. The highest yields were obtained with poplar and switchgrass (around 43%). Considering the short fibers and low yields, all four biomass types will likely only be used in paper manufacturing if they offer considerable economic advantage over traditional pulp wood.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19720527?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Katz, Jeffry</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Should probiotics be routine therapy for the prevention of antibiotic-associated diarrhea?</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of clinical gastroenterology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Clin. Gastroenterol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2010</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2010 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">44</style></volume><pages><style face="normal" font="default" size="100%">83-4</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099380?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Maestrini, Pierluigi</style></author><author><style face="normal" font="default" size="100%">Cavallini, Andrea</style></author><author><style face="normal" font="default" size="100%">Rizzo, Milena</style></author><author><style face="normal" font="default" size="100%">Giordani, Tommaso</style></author><author><style face="normal" font="default" size="100%">Bernardi, Rodolfo</style></author><author><style face="normal" font="default" size="100%">Durante, Mauro</style></author><author><style face="normal" font="default" size="100%">Natali, Lucia</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Isolation and expression analysis of low temperature-induced genes in white poplar (Populus alba).</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Sep 15</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">166</style></volume><pages><style face="normal" font="default" size="100%">1544-56</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Poplar is an important crop and a model system to understand molecular processes of growth, development and responses to environmental stimuli in trees. In this study, we analyzed gene expression in white poplar (Populus alba) plants subjected to chilling. Two forward suppression-subtractive-hybridization libraries were constructed from P. alba plants exposed to low non-freezing temperature for 6 or 48h. Hundred and sixty-two cDNAs, 54 from the 6-h library and 108 from the 48-h library, were obtained. Isolated genes belonged to six categories of genes, specifically those that: (i) encode stress and defense proteins; (ii) are involved in signal transduction; (iii) are related to regulation of gene expression; (iv) encode proteins involved in cell cycle and DNA processing; (v) encode proteins involved in metabolism and energetic processes; and (vi) are involved in protein fate. Different expression patterns at 3, 6, 12, 24, 48h at 4 degrees C and after a recovery of 24h at 20 degrees C were observed for isolated genes, as expected according to the class in which the gene putatively belongs. Forty-four of 162 genes contained DRE/LTRE cis-elements in the 5' proximal promoter of their orthologs in Populus trichocarpa, suggesting that they putatively belong to the CBF regulon. The results contribute new data to the list of possible candidate genes involved in cold response in poplar.</style></abstract><issue><style face="normal" font="default" size="100%">14</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19464753?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sun, Jian</style></author><author><style face="normal" font="default" size="100%">Dai, Songxiang</style></author><author><style face="normal" font="default" size="100%">Wang, Ruigang</style></author><author><style face="normal" font="default" size="100%">Chen, Shaoliang</style></author><author><style face="normal" font="default" size="100%">Li, Niya</style></author><author><style face="normal" font="default" size="100%">Zhou, Xiaoyang</style></author><author><style face="normal" font="default" size="100%">Lu, Cunfu</style></author><author><style face="normal" font="default" size="100%">Shen, Xin</style></author><author><style face="normal" font="default" size="100%">Zheng, Xiaojiang</style></author><author><style face="normal" font="default" size="100%">Hu, Zanmin</style></author><author><style face="normal" font="default" size="100%">Zhang, Zengkai</style></author><author><style face="normal" font="default" size="100%">Song, Jin</style></author><author><style face="normal" font="default" size="100%">Xu, Yue</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Calcium mediates root K+/Na+ homeostasis in poplar species differing in salt tolerance.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">1175-86</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Using the non-invasively ion-selective microelectrode technique, flux profiles of K(+), Na(+) and H(+) in mature roots and apical regions, and the effects of Ca(2+) on ion fluxes were investigated in salt-tolerant poplar species, Populus euphratica Oliver and salt-sensitive Populus simonii x (P. pyramidalis + Salix matsudana) (Populus popularis 35-44, P. popularis). Compared to P. popularis, P. euphratica roots exhibited a greater capacity to retain K(+) after exposure to a salt shock (SS, 100 mM NaCl) and a long-term (LT) salinity (50 mM NaCl, 3 weeks). Salt shock-induced K(+) efflux in the two species was markedly restricted by K(+) channel blocker, tetraethylammonium chloride, but enhanced by sodium orthovanadate, the inhibitor of plasma membrane (PM) H(+)-ATPase, suggesting that the K(+) efflux is mediated by depolarization-activated (DA) channels, e.g., KORCs (outward rectifying K(+) channels) and NSCCs (non-selective cation channels). Populus euphratica roots were more effective to exclude Na(+) than P. popularis in an LT experiment, resulting from the Na(+)/H(+) antiport across the PM. Moreover, pharmacological evidence implies that the greater ability to control K(+)/Na(+) homeostasis in salinized P. euphratica roots is associated with the higher H(+)-pumping activity, which provides an electrochemical H(+) gradient for Na(+)/H(+) exchange and simultaneously decreases the NaCl-induced depolarization of PM, thus reducing Na(+) influx via NSCCs and K(+) efflux through DA-KORCs and DA-NSCCs. Ca(2+) application markedly limited salt-induced K(+) efflux but enhanced the apparent Na(+) efflux, thus enabling the two species, especially the salt-sensitive poplar, to retain K(+)/Na(+) homeostasis in roots exposed to prolonged NaCl treatment.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19638360?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Xin, Gang</style></author><author><style face="normal" font="default" size="100%">Glawe, Dean</style></author><author><style face="normal" font="default" size="100%">Doty, Sharon L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Characterization of three endophytic, indole-3-acetic acid-producing yeasts occurring in Populus trees.</style></title><secondary-title><style face="normal" font="default" size="100%">Mycological research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mycol. Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">113</style></volume><pages><style face="normal" font="default" size="100%">973-80</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Three endophytic yeast, one isolated from stems of wild cottonwood (Populus trichocarpa), two from stems of hybrid poplar (P. trichocarpaxPopulus deltoides), were characterized by analyzing three ribosomal genes, the small subunit (18S), internal transcribed spacer (ITS), and D1/D2 region of the large subunit (26S). Phenotypic characteristics of the yeast isolates were also obtained using a commercial yeast identification kit and used for assisting the species identification. The isolate from wild cottonwood was identified to be closest to species Rhodotorula graminis. The two isolates from hybrid poplar were identified to be species Rhodotorula mucilaginosa. In addition, the three yeast isolates were observed to be able to produce indole-3-acetic acid (IAA), a phytohormone which can promote plant growth, when incubated with l-tryptophan. To our knowledge, the yeast strains presented in this study were the first endophytic yeast strains isolated from species of Populus.</style></abstract><issue><style face="normal" font="default" size="100%">Pt 9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19539760?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Jia, Xiaoyun</style></author><author><style face="normal" font="default" size="100%">Wang, Wang-Xia</style></author><author><style face="normal" font="default" size="100%">Ren, Ligang</style></author><author><style face="normal" font="default" size="100%">Chen, Qi-Jun</style></author><author><style face="normal" font="default" size="100%">Mendu, Venugopal</style></author><author><style face="normal" font="default" size="100%">Willcut, Benjamin</style></author><author><style face="normal" font="default" size="100%">Dinkins, Randy</style></author><author><style face="normal" font="default" size="100%">Tang, Xiaoqing</style></author><author><style face="normal" font="default" size="100%">Tang, Guiliang</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Differential and dynamic regulation of miR398 in response to ABA and salt stress in Populus tremula and Arabidopsis thaliana.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Mol. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">71</style></volume><pages><style face="normal" font="default" size="100%">51-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">MicroRNAs (miRNAs) are endogenous small RNAs of ~22 nucleotides (nt) that play a key role in down regulation of gene expression at the post-transcriptional level in plants and animals. Various studies have identified numerous miRNAs that were either up regulated or down regulated upon stress treatment. Here, we sought to understand the temporal regulation of miRNAs in different plant species under abscisic acid (ABA) and salt (NaCl) stress. Our results showed that the regulation of miR398 in response to ABA and salt stress was more dynamic in plants than previously reported. In poplars, miR398 was first induced upon 3-4 h of ABA or salt stress. However, this induction declined after 48 h and finally accumulated again over a prolonged stress (72 h). We referred to this kind of regulation as dynamic regulation. In contrast, such dynamic regulation of miR398 under salt stress was completely absent in Arabidopsis, in which miR398 was steadily and unidirectionally suppressed. Interestingly, ABA treatment caused a deviate dynamic regulation of miR398 in Arabidopsis, showing an opposite response as compared to that in poplars. We referred to the difference in regulation between Arabidopsis and poplars as differential regulation. Furthermore, the expression of the miR398 target, copper superoxide dismutase1 (CSD1), was in reverse correlation with the miR398 level, suggesting a control of this specific target expression predominantly by miR398 under abiotic stress. Together, these data consistently show a correlated regulation between miR398 and its representative target, CSD1, by ABA and salt stresses, and raise the possibility that regulation of miRNAs in plants is twofold: a dynamic regulation within a plant species and a differential regulation between different plant species.</style></abstract><issue><style face="normal" font="default" size="100%">1-2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19533381?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hartikainen, Kaisa</style></author><author><style face="normal" font="default" size="100%">Nerg, Anne-Marja</style></author><author><style face="normal" font="default" size="100%">Kivimäenpää, Minna</style></author><author><style face="normal" font="default" size="100%">Kontunen-Soppela, Sari</style></author><author><style face="normal" font="default" size="100%">Mäenpää, Maarit</style></author><author><style face="normal" font="default" size="100%">Oksanen, Elina</style></author><author><style face="normal" font="default" size="100%">Rousi, Matti</style></author><author><style face="normal" font="default" size="100%">Holopainen, Toini</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Emissions of volatile organic compounds and leaf structural characteristics of European aspen (Populus tremula) grown under elevated ozone and temperature.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">1163-73</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Northern forest trees are challenged to adapt to changing climate, including global warming and increasing tropospheric ozone (O(3)) concentrations. Both elevated O(3) and temperature can cause significant changes in volatile organic compound (VOC) emissions as well as in leaf anatomy that can be related to adaptation or increased stress tolerance, or are signs of damage. Impacts of moderately elevated O(3) (1.3x ambient) and temperature (ambient + 1 degrees C), alone and in combination, on VOC emissions and leaf structure of two genotypes (2.2 and 5.2) of European aspen (Populus tremula L.) were studied in an open-field experiment in summer 2007. The impact of O(3) on measured variables was minor, but elevated temperature significantly increased emissions of total monoterpenes and green leaf volatiles. Genotypic differences in the responses to warming treatment were also observed. alpha-Pinene emission, which has been suggested to protect plants from elevated temperature, increased from genotype 5.2 only. Isoprene emission from genotype 2.2 decreased, whereas genotype 5.2 was able to retain high isoprene emission level also under elevated temperature. Elevated temperature also caused formation of thinner leaves, which was related to thinning of epidermis, palisade and spongy layers as well as reduced area of palisade cells. We consider aspen genotype 5.2 to have better potential for adaptation to increasing temperature because of thicker photosynthetic active palisade layer and higher isoprene and alpha-pinene emission levels compared to genotype 2.2. Our results show that even a moderate elevation in temperature is efficient enough to cause notable changes in VOC emissions and leaf structure of these aspen genotypes, possibly indicating the effort of the saplings to adapt to changing climate.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19448266?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rasulov, Bahtijor</style></author><author><style face="normal" font="default" size="100%">Hüve, Katja</style></author><author><style face="normal" font="default" size="100%">Välbe, Mikk</style></author><author><style face="normal" font="default" size="100%">Laisk, Agu</style></author><author><style face="normal" font="default" size="100%">Niinemets, Ulo</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Evidence that light, carbon dioxide, and oxygen dependencies of leaf isoprene emission are driven by energy status in hybrid aspen.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">151</style></volume><pages><style face="normal" font="default" size="100%">448-60</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Leaf isoprene emission scales positively with light intensity, is inhibited by high carbon dioxide (CO(2)) concentrations, and may be enhanced or inhibited by low oxygen (O(2)) concentrations, but the mechanisms of environmental regulation of isoprene emission are still not fully understood. Emission controls by isoprene synthase, availability of carbon intermediates, or energetic cofactors have been suggested previously. In this study, we asked whether the short-term (tens of minutes) environmental control of isoprene synthesis results from alterations in the immediate isoprene precursor dimethylallyldiphosphate (DMADP) pool size, and to what extent DMADP concentrations are affected by the supply of carbon and energetic metabolites. A novel in vivo method based on postillumination isoprene release was employed to measure the pool size of DMADP simultaneously with the rates of isoprene emission and net assimilation at different light intensities and CO(2) and O(2) concentrations. Both net assimilation and isoprene emission rates increased hyperbolically with light intensity. The photosynthetic response to CO(2) concentration was also hyperbolic, while the CO(2) response curve of isoprene emission exhibited a maximum at close to CO(2) compensation point. Low O(2) positively affected both net assimilation and isoprene emission. In all cases, the variation in isoprene emission was matched with changes in DMADP pool size. The results of these experiments suggest that DMADP pool size controls the response of isoprene emission to light intensity and to CO(2) and O(2) concentrations and that the pool size is determined by the level of energetic metabolites generated in photosynthesis.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19587097?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lojewski, Nathan R</style></author><author><style face="normal" font="default" size="100%">Fischer, Dylan G</style></author><author><style face="normal" font="default" size="100%">Bailey, Joseph K</style></author><author><style face="normal" font="default" size="100%">Schweitzer, Jennifer A</style></author><author><style face="normal" font="default" size="100%">Whitham, Thomas G</style></author><author><style face="normal" font="default" size="100%">Hart, Stephen C</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genetic basis of aboveground productivity in two native Populus species and their hybrids.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">1133-42</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Demonstration of genetic control over riparian tree productivity has major implications for responses of riparian systems to shifting environmental conditions and effects of genetics on ecosystems in general. We used field studies and common gardens, applying both molecular and quantitative techniques, to compare plot-level tree aboveground net primary productivity (ANPP(tree)) and individual tree growth rate constants in relation to plant genetic identity in two naturally occurring Populus tree species and their hybrids. In field comparisons of four cross types (Populus fremontii S. Wats., Populus angustifolia James, F(1) hybrids and backcross hybrids) across 11 natural stands, productivity was greatest for P. fremontii trees, followed by hybrids and lowest in P. angustifolia. A similar pattern was observed in four common gardens across a 290 m elevation and 100 km environmental gradient. Despite a doubling in productivity across the common gardens, the relative differences among the cross types remained constant. Using clonal replicates in a common garden, we found ANPP(tree) to be a heritable plant trait (i.e., broad-sense heritability), such that plant genetic factors explained between 38% and 82% of the variation in ANPP(tree). Furthermore, analysis of the genetic composition among individual tree genotypes using restriction fragment length polymorphism molecular markers showed that genetically similar trees also exhibited similar ANPP(tree). These findings indicate strong genetic contributions to natural variation in ANPP with important ecological implications.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19578030?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bonhomme, Ludovic</style></author><author><style face="normal" font="default" size="100%">Monclus, Romain</style></author><author><style face="normal" font="default" size="100%">Vincent, Delphine</style></author><author><style face="normal" font="default" size="100%">Carpin, Sabine</style></author><author><style face="normal" font="default" size="100%">Lomenech, Anne-Marie</style></author><author><style face="normal" font="default" size="100%">Plomion, Christophe</style></author><author><style face="normal" font="default" size="100%">Brignolas, Franck</style></author><author><style face="normal" font="default" size="100%">Morabito, Domenico</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Leaf proteome analysis of eight Populus xeuramericana genotypes: genetic variation in drought response and in water-use efficiency involves photosynthesis-related proteins.</style></title><secondary-title><style face="normal" font="default" size="100%">Proteomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Proteomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">4121-42</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Genetic variation of leaf proteome in drought response was investigated among eight Populus xeuramericana genotypes contrasting for their leaf carbon isotope discrimination (Delta), an estimate of intrinsic water-use efficiency. Plants were grown in open field on two similar plots. Drought was induced by an 86-day irrigation cessation on one plot, whereas a second plot remained regularly irrigated. Using 2-DE, 863 reproducible spots were detected; about 60% presented at least one significant effect i.e. treatment, genotype and/or genotype by treatment interaction effect. A significant genotype by treatment interaction was detected for 62 reliably identified proteins among which, about 65% consisted in chloroplast-associated proteins either involved in the Calvin cycle or in the electron-transport chains. The other proteins were involved in oxidative stress, amino acid or protein metabolisms. Correlations between protein abundance and Delta variations were found for 45 reliably identified proteins. The abundance of ribulose-1,5-bisphosphate carboxylase/oxygenase activase isoforms scaled negatively with Delta regardless of the treatment, suggesting that a large intrinsic water-use efficiency could be due to higher abundance of ribulose-1,5-bisphosphate carboxylase/oxygenase activase. Under control condition, abundance of enzymes involved in carbon fixation was also negatively correlated with Delta, whereas abundance of enzymes involved in photorespiration or respiration was positively correlated with Delta.</style></abstract><issue><style face="normal" font="default" size="100%">17</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19722189?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Péter, Gábor</style></author><author><style face="normal" font="default" size="100%">Tornai-Lehoczki, Judit</style></author><author><style face="normal" font="default" size="100%">Dlauchy, Dénes</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Ogataea populialbae sp. nov., a yeast species from white poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">FEMS yeast research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">FEMS Yeast Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">936-41</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">During a survey of methylotrophic yeasts in natural habitats in Hungary, the yeast community associated with the exudates of white poplar (Populus alba) was found to be unique among the tree exudates hitherto investigated. Nineteen methanol-assimilating yeast strains representing an undescribed ascomycetous species were isolated from tree exudates of P. alba collected at different locations in Hungary. Analysis of the D1/D2 large subunit rRNA gene sequences placed the strains in the Ogataea clade and the new species is described as Ogataea populialbae. The type culture is NCAIM Y.01853(T) (CBS 11363, NRRL Y-48632).</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19645773?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kumar, Rajeev</style></author><author><style face="normal" font="default" size="100%">Mago, Gaurav</style></author><author><style face="normal" font="default" size="100%">Balan, Venkatesh</style></author><author><style face="normal" font="default" size="100%">Wyman, Charles E</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Physical and chemical characterizations of corn stover and poplar solids resulting from leading pretreatment technologies.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioresource technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bioresour. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">100</style></volume><pages><style face="normal" font="default" size="100%">3948-62</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In order to investigate changes in substrate chemical and physical features after pretreatment, several characterizations were performed on untreated (UT) corn stover and poplar and their solids resulting pretreatments by ammonia fiber expansion (AFEX), ammonia recycled percolation (ARP), controlled pH, dilute acid, flowthrough, lime, and SO(2) technologies. In addition to measuring the chemical compositions including acetyl content, physical attributes determined were biomass crystallinity, cellulose degree of polymerization, cellulase adsorption capacity of pretreated solids and enzymatically extracted lignin, copper number, FT-IR responses, scanning electron microscopy (SEM) visualizations, and surface atomic composition by electron spectroscopy of chemical analysis (ESCA). Lime pretreatment removed the most acetyl groups from both corn stover and poplar, while AFEX removed the least. Low pH pretreatments depolymerized cellulose and enhanced biomass crystallinity much more than higher pH approaches. Lime pretreated corn stover solids and flowthrough pretreated poplar solids had the highest cellulase adsorption capacity, while dilute acid pretreated corn stover solids and controlled pH pretreated poplar solids had the least. Furthermore, enzymatically extracted AFEX lignin preparations for both corn stover and poplar had the lowest cellulase adsorption capacity. ESCA results showed that SO(2) pretreated solids had the highest surface O/C ratio for poplar, but for corn stover, the highest value was observed for dilute acid pretreatment with a Parr reactor. Although dependent on pretreatment and substrate, FT-IR data showed that along with changes in cross linking and chemical changes, pretreatments may also decrystallize cellulose and change the ratio of crystalline cellulose polymorphs (Ialpha/Ibeta).</style></abstract><issue><style face="normal" font="default" size="100%">17</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19362819?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Djazouli, Zahr-Eddine</style></author><author><style face="normal" font="default" size="100%">Doumandji-Mitiche, Bahia</style></author><author><style face="normal" font="default" size="100%">Petit, Daniel</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Spatio-temporal variations of functional groups in a Populus nigra L. entomocenosis in the Mitidja plain (Algeria).</style></title><secondary-title><style face="normal" font="default" size="100%">Comptes rendus biologies</style></secondary-title><alt-title><style face="normal" font="default" size="100%">C. R. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">332</style></volume><pages><style face="normal" font="default" size="100%">848-60</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">This study presents the first data describing the communities of insects and arachnida colonizing 4 aerial compartments of Populus nigra. In terms of temporal variation and total abundance, the analyses show that the communities are structurally and functionally different. It also appears that the taxonomic richness of the communities, and partly their temporal distribution, change according to the gradient of the energy and defense resources under the effect of seasonal variations. The highest species richness recorded on the leaves compartment is due to the amplitude of histo-physiological modifications observed throughout the growing season.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19748459?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Coutand, Catherine</style></author><author><style face="normal" font="default" size="100%">Martin, Ludovic</style></author><author><style face="normal" font="default" size="100%">Leblanc-Fournier, Nathalie</style></author><author><style face="normal" font="default" size="100%">Decourteix, Mélanie</style></author><author><style face="normal" font="default" size="100%">Julien, Jean-Louis</style></author><author><style face="normal" font="default" size="100%">Moulia, Bruno</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Strain mechanosensing quantitatively controls diameter growth and PtaZFP2 gene expression in poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">151</style></volume><pages><style face="normal" font="default" size="100%">223-32</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Mechanical signals are important factors that control plant growth and development. External mechanical loadings lead to a decrease in elongation and a stimulation of diameter growth, a syndrome known as thigmomorphogenesis. A previous study has demonstrated that plants perceive the strains they are subjected to and not forces or stresses. On this basis, an integrative biomechanical model of mechanosensing was established (&quot;sum-of-strains model&quot;) and tested on tomato (Solanum lycopersicum) elongation but not for local responses such as diameter growth or gene expression. The first aim of this interdisciplinary work was to provide a quantitative study of the effect of a single transitory bending on poplar (Populus tremula x alba) diameter growth and on the expression level of a primary mechanosensitive transcription factor gene, PtaZFP2. The second aim of this work was to assess the sum-of-strains model of mechanosensing on these local responses. An original bending device was built to study stem responses according to a controlled range of strains. A single bending modified plant diameter growth and increased the relative abundance of PtaZFP2 transcripts. Integrals of longitudinal strains induced by bending on the responding tissues were highly correlated to local plant responses. The sum-of-strains model of mechanosensing established for stem elongation was thus applicable for local responses at two scales: diameter growth and gene expression. These novel results open avenues for the ordering of gene expression profiles as a function of the intensity of mechanical stimulation and provide a generic biomechanical core for an integrative model of thigmomorphogenesis linking gene expression with growth responses.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19571311?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Li, Bosheng</style></author><author><style face="normal" font="default" size="100%">Yin, Weilun</style></author><author><style face="normal" font="default" size="100%">Xia, Xinli</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Identification of microRNAs and their targets from Populus euphratica.</style></title><secondary-title><style face="normal" font="default" size="100%">Biochemical and biophysical research communications</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biochem. Biophys. Res. Commun.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Oct 16</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">388</style></volume><pages><style face="normal" font="default" size="100%">272-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Populus euphratica is an ideal model system for research into the abiotic stress resistance research of woody plants. Although microRNAs have been found in poplars and have been shown to have diverse biological functions, a majority of them are genus- or specie-specific and few microRNAs have been found in P. euphratica to date. In this study, microRNA cloning and computational expressed sequence tag analysis were used to identify 72 putative miRNA sequences in P. euphratica. These sequences could be classified into 21 families, 12 of which were novel, increasing the number of known poplar microRNA families from 42 to 54. Expression analysis indicated that five P. euphratica microRNAs were induced by dehydration stress. Bioinformatics prediction showed that the 130 target genes are involved in development, resistance to stress, and other cellular processes. These results suggest several roles for miRNAs in the regulatory networks associated with the abiotic stress resistance of tree species.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19664594?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Liu, Jiyan</style></author><author><style face="normal" font="default" size="100%">Hu, Dingfei</style></author><author><style face="normal" font="default" size="100%">Jiang, Guibin</style></author><author><style face="normal" font="default" size="100%">Schnoor, Jerald L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">In vivo biotransformation of 3,3',4,4'-tetrachlorobiphenyl by whole plants-poplars and switchgrass.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental science &amp; technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Sci. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Oct 1</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">43</style></volume><pages><style face="normal" font="default" size="100%">7503-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Polychlorinated biphenyls (PCBs) are widely distributed persistent organic pollutants. In vitro research has shown that plant cell cultures might transform lower chlorinated congeners to hydroxylated PCBs, but there are few studies on in vivo metabolism of PCBs by intact whole plants. In this research, poplar plants (Populus deltoides x nigra, DN34) and switchgrass (Panicum vigratum, Alamo) were hydroponically exposed to 3,3',4,4'-tetrachlorobiphenyl (CB77). Metabolism in plants occurred rapidly, and metabolites were detected after only a 24 h exposure. Rearrangement of chlorine atoms and dechlorination of CB77 by plants was unexpectedly observed. In addition, poplars were able to hydroxylate CB77 and the metabolite 6-hydroxy-3,3,4,4'-tetrachlorobiphenyl 6-OH-CB77) was identified and quantified. Hybrid poplar was able to hydroxylate CB77, but switchgrass was not, suggesting that enzymatic transformations are plant specific. Sulfur-containing metabolites (from the action of sulfotransferases) were investigated in this study, but they were not detected in either poplar or switchgrass.</style></abstract><issue><style face="normal" font="default" size="100%">19</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19848168?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">St Clair, Samuel B</style></author><author><style face="normal" font="default" size="100%">Monson, Steven D</style></author><author><style face="normal" font="default" size="100%">Smith, Eric A</style></author><author><style face="normal" font="default" size="100%">Cahill, David G</style></author><author><style face="normal" font="default" size="100%">Calder, William J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Altered leaf morphology, leaf resource dilution and defense chemistry induction in frost-defoliated aspen (Populus tremuloides).</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">1259-68</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In May 2007, a widespread frost event defoliated much of Utah's high elevation aspen. About 5 weeks later, the frost-defoliated aspen produced a second leaf flush. The objective of this study was to characterize changes in leaf morphology and function in re-flush leaves following frost defoliation. Leaf size and thickness, photosynthesis, carbohydrate and nutrient status, and defense chemistry (phenolic glycosides and condensed tannins) were measured in first and second flush leaves. The second flush leaves produced two different morphological responses depending on frost damage severity. Severe frost damage was characterized by patchy canopy re-flushing with leaves that were on average four times larger than the first flush leaves. Moderate frost damage produced full canopy flushes with second flush leaves that were typically smaller than the first flush leaves. The second flush leaves tended to be thicker, and had significantly lower nutrient and sucrose concentrations, but had equal or higher rates of photosynthesis. These leaves showed a general pattern of defense chemistry induction with phenolic glycosides and condensed tannins increasing two- to threefold. Some of the changes in leaf morphology and defense chemistry observed in second flush leaves in 2007 persisted in leaves produced in the following year. We hypothesize that defense chemistry induction following abiotic defoliation serves as insurance against secondary defoliation events by herbivores that may further deplete nutrient and carbohydrate leaf resources below threshold points that are critical for physiological function. Resource dilution and allocation to secondary defense may place constraints on growth capacity.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19671568?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zheng, Huiquan</style></author><author><style face="normal" font="default" size="100%">Lin, Shanzhi</style></author><author><style face="normal" font="default" size="100%">Zhang, Qian</style></author><author><style face="normal" font="default" size="100%">Lei, Yang</style></author><author><style face="normal" font="default" size="100%">Zhang, Zhiyi</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Functional analysis of 5' untranslated region of a TIR-NBS-encoding gene from triploid white poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular genetics and genomics : MGG</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Genet. Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">282</style></volume><pages><style face="normal" font="default" size="100%">381-94</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Genome-wide analyses have identified a set of TIR-NBS-encoding genes in plants. However, the molecular mechanism underlying the expression of these genes is still unknown. In this study, we presented a TIR-NBS-encoding gene, PtDrl02, that displayed a low level of tissue-specific expression in a triploid white poplar [(Populus tomentosa x P. bolleana) x P. tomentosa], and analyzed the effects of the 5' untranslated region (UTR) on gene expression. The 5' UTR sequence repressed the reporter activity of beta-glucuronidase (GUS) gene under PtDrl02 promoter by 113.5-fold with a staining ratio of 2.97% in the transgenic tobacco plants. Quantitative RT-PCR assays revealed that the 5' UTR sequence decreased the transcript level of the GUS reporter gene by 13.3-fold, implying a regulatory role of 5' UTR in transcription and/or mRNA destabilization. The comparison of GUS activity with the transcript abundance indicated that the 5' UTR sequence decreased the translation efficiency of target gene by 88.3%. Additionally, the analysis of the transgenic P-985/UTRDelta/GUS plants showed that both the exon1 sequence and the leading intron within the 5' UTR region were responsible for the regulation of gene expression. Our results suggested a negative effect of the 5' UTR of PtDrl02 gene on gene expression.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19618215?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Castro, Maria Elita B</style></author><author><style face="normal" font="default" size="100%">Ribeiro, Zilda Maria A</style></author><author><style face="normal" font="default" size="100%">Santos, Ana Cláudia B</style></author><author><style face="normal" font="default" size="100%">Souza, Marlinda L</style></author><author><style face="normal" font="default" size="100%">Machado, Edilene B</style></author><author><style face="normal" font="default" size="100%">Sousa, Nilton J</style></author><author><style face="normal" font="default" size="100%">Moscardi, Flávio</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Identification of a new nucleopolyhedrovirus from naturally-infected Condylorrhiza vestigialis (Guenée) (Lepidoptera: Crambidae) larvae on poplar plantations in South Brazil.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of invertebrate pathology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Invertebr. Pathol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">102</style></volume><pages><style face="normal" font="default" size="100%">149-54</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A baculovirus was isolated from larvae of Condylorrhiza vestigialis (Guenée) (Lepidoptera: Crambidae), a pest of a forest species known as Poplar (family Salicaceae, genus: Populus) with high economic value. Electron microscopy analysis of the occlusion body obtained from diseased larvae showed polyhedra containing multiple nucleocapsids per envelope. This baculovirus was thus named Condylorrhiza vestigialis multiple nucleopolyhedrovirus (CoveMNPV) and characterized by its DNA restriction endonuclease pattern, polyhedral protein, viral protein synthesis, and infectivity in insect cell lines. Restriction endonuclease profiles of viral DNA digested with five restriction enzymes were obtained and the CoveMNPV genome size was estimated to be 81+/-2.5 kbp. The isolation of the polyhedra (OBs) was done from the crude extract of infected larvae by ultracentrifugation through sucrose gradients. These viral particles were analyzed by denaturing polyacrylamide gel electrophoresis (SDS-PAGE), which showed a strong band with approximately 33 kDa, corresponding to the main protein of the occlusion bodies (polyhedrin). Also, a similar band was observed for CoveMNPV infected Spodoptera frugiperda cells (SF-21 AE) pulse-labeled with [(35)S] methionine and fractionated by SDS-PAGE. Of the four insect cell lines tested for susceptibility to CoveMNPV infection, the SF-21 AE was the most susceptible with occlusion bodies produced in most of the inoculated cells. This is the first record of an NPV from C. vestigialis.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19651137?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gálvez, David A</style></author><author><style face="normal" font="default" size="100%">Tyree, M T</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Impact of simulated herbivory on water relations of aspen (Populus tremuloides) seedlings: the role of new tissue in the hydraulic conductivity recovery cycle.</style></title><secondary-title><style face="normal" font="default" size="100%">Oecologia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Oecologia</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">161</style></volume><pages><style face="normal" font="default" size="100%">665-71</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Physiological mechanisms behind plant-herbivore interactions are commonly approached as input-output systems where the role of plant physiology is viewed as a black box. Studies evaluating impacts of defoliation on plant physiology have mostly focused on changes in photosynthesis while the overall impact on plant water relations is largely unknown. Stem hydraulic conductivity (k(h)), stem specific conductivity (k(s)), percent loss of hydraulic conductivity (PLC), CO(2) assimilation (A) and stomatal conductance (g(s)) were measured on well-irrigated 1-month-old Populus tremuloides (Michx.) defoliated and control seedlings until complete refoliation. PLC values of defoliated seedlings gradually increased during the refoliation process despite them being kept well irrigated. k(s) of defoliated seedlings gradually decreased during refoliation. PLC and k(s) values of control seedlings remained constant during refoliation. k(s) of new stems, leaf specific conductivity and A of leaves grown from new stems in defoliated and control seedlings were not significantly different, but g(s) was higher in defoliated than in control seedlings. The gradual increase of PLC and decrease of k(s) values in old stems after defoliation was unexpected under well-irrigated conditions, but appeared to have little impact on new stems formed after defoliation. The gradual loss of conductivity measured during the refoliation process under well-irrigated conditions suggests that young seedlings of P. tremuloides may be more susceptible to cavitation after herbivore damage under drought conditions.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19603186?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Deslauriers, Annie</style></author><author><style face="normal" font="default" size="100%">Giovannelli, Alessio</style></author><author><style face="normal" font="default" size="100%">Rossi, Sergio</style></author><author><style face="normal" font="default" size="100%">Castro, Gaetano</style></author><author><style face="normal" font="default" size="100%">Fragnelli, Giuseppe</style></author><author><style face="normal" font="default" size="100%">Traversi, Laura</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Intra-annual cambial activity and carbon availability in stem of poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">1223-35</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Cambial activity is influenced by many environmental and physiological factors and among them, carbon acts as a source of energy for the growing meristems. This work has focused on the intra-annual stem growth of poplar compared with the carbon available for xylogenesis processes in cambium and outer wood. The major stages of xylem production and differentiation in two poplar genotypes with different growth performances were considered. Monitoring of stem growth and leaf phenology combined with starch, nonstructural soluble sugars and water content in the stem was conducted from February to November 2006 in Populus x canadensis Moench 'I-214' and Populus deltoides Marsh. 'Dvina'. Anatomical analyses of wood formation were performed by measuring the width of the zones with differentiating and mature xylem. At the end of the growing period, wood density was assessed by microdensity analyses. Xylem differentiation at the top of the tree started at the beginning of April for both genotypes and proceeded down the stem at about 0.5 m day(-1), occurring almost at the same time as leaf opening. The rate of growth and wood density was superior in Dvina, but this higher productivity could not be explained by differences in the number of cambial initials and the duration of xylogenesis. However, the most productive poplar genotype showed higher glucose, fructose and sucrose content in the outer wood. The nonstructural soluble sugars available in the cambial zone followed the intra-annual pattern of xylem formation, with a higher concentration when the growth rate was maximum. The accumulations of nonstructural soluble sugars at a certain time during stem growth corresponded with a higher carbon availability to the actively growing meristems in the stem.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19696052?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zeng, Fanjiang</style></author><author><style face="normal" font="default" size="100%">Yan, Hailong</style></author><author><style face="normal" font="default" size="100%">Arndt, Stefan K</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Leaf and whole tree adaptations to mild salinity in field grown Populus euphratica.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">1237-46</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Populus euphratica Oliv. is a highly salt tolerant tree species, and this study represents the first comprehensive investigation of salt tolerance mechanisms of mature trees of P. euphratica in the field. We measured NaCl concentration in xylem sap, NaCl accumulation in leaves, the effect of NaCl on leaf physiological parameters and osmotic adjustment and the allocation and distribution of NaCl between different plant organs on a whole plant level in trees exposed to mild saline groundwater (around 30 mM) in China. Populus euphratica showed three key mechanisms of salt tolerance. The primary mechanism had a strong control over Na(+) and Cl(-) uptake with effective exclusion mechanisms for Cl(-) with up to 99% of the external NaCl being excluded from the xylem. Secondly, the trees allocated large proportions of NaCl into the leaves, which served as a salt elimination mechanism as the leaves are ultimately shed at the end of the growing season. Thirdly, the trees tolerated high foliar Na(+) concentrations through a combination of osmotic adjustment using sucrose and probable sequestering of Na(+) in the apoplast. Our results indicate that the control of Na(+) and Cl(-) uptake and the regulation of Na(+) and Cl(-) delivery to the shoot are key to salt tolerance of P. euphratica in the field with tolerance of high Na(+) concentrations in leaves being a critical component.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19661134?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kalcsits, Lee</style></author><author><style face="normal" font="default" size="100%">Kendall, Edward</style></author><author><style face="normal" font="default" size="100%">Silim, Salim</style></author><author><style face="normal" font="default" size="100%">Tanino, Karen</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Magnetic resonance microimaging indicates water diffusion correlates with dormancy induction in cultured hybrid poplar (Populus spp.) buds.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">1269-77</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Water content and mobility, which are factors known to be associated with dormancy induction in woody plants on a tissue level, were measured using non-destructive magnetic resonance microimaging (MRMI). Two cultured poplar clones ('Okanese' - temperature-insensitive dormancy and 'Walker' - temperature-sensitive dormancy) were subjected to dormancy differentiating temperature regimes, 18.5/3.5 degrees C and 18.5/13.5 degrees C (day/night), under a short photoperiod. Apparent diffusion coefficient, an indicator of water mobility, correlated with dormancy development in the axillary bud and vascular bud trace regions. In contrast, T(1) relaxation time, an indicator of static biophysical water properties, did not correlate significantly with dormancy in the regions that were examined. Although MRMI studies using T(1) relaxation measurements have dominated the phytological field, our work indicates that water mobility is an important factor in studies examining water changes during dormancy induction in the critical tissues of woody plants.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19696054?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ye, Chu-Yu</style></author><author><style face="normal" font="default" size="100%">Zhang, He-Chen</style></author><author><style face="normal" font="default" size="100%">Chen, Jin-Huan</style></author><author><style face="normal" font="default" size="100%">Xia, Xin-Li</style></author><author><style face="normal" font="default" size="100%">Yin, Wei-Lun</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Molecular characterization of putative vacuolar NHX-type Na(+)/H(+) exchanger genes from the salt-resistant tree Populus euphratica.</style></title><secondary-title><style face="normal" font="default" size="100%">Physiologia plantarum</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Physiol Plant</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">137</style></volume><pages><style face="normal" font="default" size="100%">166-74</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The vacuolar NHX-type Na(+)/H(+) exchangers play a key role in salt tolerance in plants. However, little is known about the Na(+)/H(+) exchangers in the salt-resistant tree, Populus euphratica. In this study, we identified six putative vacuolar Na(+)/H(+) exchanger genes from P. euphratica, designated as PeNHX1-6. Real-time polymerase chain reaction indicated that the PeNHX1/3/6 transcripts were abundant compared with the other three PeNHX genes in the three tissues (roots, stems and leaves) examined. After NaCl treatment for 6 h, the transcript levels of PeNHX1-6 were upregulated in the roots. To address the function of PeNHX1-6, complementation studies were performed with the salt-sensitive yeast mutant strain R100, which lacks activity of the endosomal Na(+)/H(+) antiporter NHX1. The results showed that PeNHX1-6 compensates, at least in part, for the function of yeast NHX1. Moreover, PeNHX3 was targeted to the tonoplast when transiently expressed in onion. Together, these results suggest that PeNHX1-6 function as vacuolar Na(+)/H(+) exchangers and that PeNHX products play an important role in the salt resistance of P. euphratica.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19678897?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhao, Hongxia</style></author><author><style face="normal" font="default" size="100%">Li, Yan</style></author><author><style face="normal" font="default" size="100%">Duan, Baoli</style></author><author><style face="normal" font="default" size="100%">Korpelainen, Helena</style></author><author><style face="normal" font="default" size="100%">Li, Chunyang</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Sex-related adaptive responses of Populus cathayana to photoperiod transitions.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">32</style></volume><pages><style face="normal" font="default" size="100%">1401-11</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Populus cathayana Rehd., a dioecious tree species, occupies a wide range of habitats in southwest China. Both males and females were grown under two regimes of photoperiod, from mid-length to short-day photoperiod (SD shift), or to long-day photoperiod (LD shift). SD shift triggered leaf senescence in both males and females by decreasing net photosynthesis rate (A), transpiration (E), and chlorophyll pigment (Chl), non-structural carbohydrate (NSC) and indoleacetic acid (IAA) contents, while increasing abscisic acid (ABA), malonaldehyde (MDA) and free proline (Pro) contents. The antioxidant enzyme (e.g. POD, CAT and SOD) activities and capability to maintain ultrastructural integrity also decreased under SD shift. Males exhibited faster leaf senescence than did females, as shown by greater decreases in A, E, Chl and IAA. However, males maintained a less senescent stage than did females, as indicated by higher values of A, Chl, NSC, IAA and antioxidant enzyme activities. Conversely, A, E, NSC and IAA contents and antioxidant enzyme activities were enhanced by lower O(2)(*-) in females, whereas reduced by higher O(2)(*-) in males under LD shift. Such sex-dependent responses of P. cathayana to photoperiod transitions showed that males and females possess different adaptabilities, which may relate to sex-specific leaf senescence speed under changing environments.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19552665?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sankoff, David</style></author><author><style face="normal" font="default" size="100%">Zheng, Chunfang</style></author><author><style face="normal" font="default" size="100%">Wall, P Kerr</style></author><author><style face="normal" font="default" size="100%">dePamphilis, Claude</style></author><author><style face="normal" font="default" size="100%">Leebens-Mack, Jim</style></author><author><style face="normal" font="default" size="100%">Albert, Victor A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Towards improved reconstruction of ancestral gene order in angiosperm phylogeny.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of computational biology : a journal of computational molecular cell biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Comput. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">16</style></volume><pages><style face="normal" font="default" size="100%">1353-67</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Whole genome doubling (WGD), a frequent occurrence during the evolution of the angiosperms, complicates ancestral gene order reconstruction due to the multiplicity of solutions to the genome halving process. Using the genome of a related species (the outgroup) to guide the halving of a WGD descendant attenuates this problem. We investigate a battery of techniques for further improvement, including an unbiased version of the guided genome halving algorithm, reference to two related genomes instead of only one to guide the reconstruction, use of draft genome sequences in contig form only, incorporation of incomplete sets of homology correspondences among the genomes, and addition of large numbers of &quot;singleton&quot; correspondences. We make use of genomic distance, breakpoint reuse rate, dispersion of sets of alternate solutions, and other means to evaluate these techniques, and employ the papaya (Carica papaya) and grapevine (Vitis vinifera) genomes to reconstruct the pre-WGD ancestor of poplar (Populus trichocarpa), as well as an early rosid ancestor. A significant result is that the papaya genome has rearranged at a greater rate from the rosid ancestor than phylogenetic relationships would predict.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19803735?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Alekseeva, I A</style></author><author><style face="normal" font="default" size="100%">Chuprina, R P</style></author><author><style face="normal" font="default" size="100%">Davydov, D S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Assessment of consistency of technological process using control cards on the example of analysis of information on immunogenic activity of pertussis component of DTP vaccine].</style></title><secondary-title><style face="normal" font="default" size="100%">Zhurnal mikrobiologii, epidemiologii, i immunobiologii</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Zh. Mikrobiol. Epidemiol. Immunobiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Nov-Dec</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">70-5</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">To assess the consistency of technological process of manufacture of DTP vaccine's pertussis component on the basis of its immunogenicity using Shewhart's cards.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099396?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Mertsalova, N U</style></author><author><style face="normal" font="default" size="100%">Borisova, O Iu</style></author><author><style face="normal" font="default" size="100%">Shinkarev, A S</style></author><author><style face="normal" font="default" size="100%">Britsina, M V</style></author><author><style face="normal" font="default" size="100%">Ozeretskovskaia, M N</style></author><author><style face="normal" font="default" size="100%">Mazurova, I K</style></author><author><style face="normal" font="default" size="100%">Aleshkin, V A</style></author><author><style face="normal" font="default" size="100%">Gadua, N T</style></author><author><style face="normal" font="default" size="100%">Zakharova, N S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Dynamics of changes in pathogenic characteristics of Bordetella pertussis strains].</style></title><secondary-title><style face="normal" font="default" size="100%">Zhurnal mikrobiologii, epidemiologii, i immunobiologii</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Zh. Mikrobiol. Epidemiol. Immunobiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Nov-Dec</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">7-11</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">To study pathogenic characteristics of B. pertussis strains isolated from patients during different periods of pertussis infection epidemic process.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099391?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Akhtarieva, A A</style></author><author><style face="normal" font="default" size="100%">Dolgushin, I I</style></author><author><style face="normal" font="default" size="100%">Gabidullin, Z G</style></author><author><style face="normal" font="default" size="100%">Gabidullin, Iu Z</style></author><author><style face="normal" font="default" size="100%">Kamalova, A A</style></author><author><style face="normal" font="default" size="100%">Akhmadeev, R M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Effect of Enterobacter cloacae thermolabile enterotoxin on immune system of mice].</style></title><secondary-title><style face="normal" font="default" size="100%">Zhurnal mikrobiologii, epidemiologii, i immunobiologii</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Zh. Mikrobiol. Epidemiol. Immunobiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Nov-Dec</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">98-104</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">To study the effect of Enterobactercloacae thermolabile enterotoxin (LT-enterotoxin) on different arms of immune system of mice.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099397?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Maletskaia, O V</style></author><author><style face="normal" font="default" size="100%">Kulichenko, A N</style></author><author><style face="normal" font="default" size="100%">Beĭer, A P</style></author><author><style face="normal" font="default" size="100%">Grizhebovskiĭ, G M</style></author><author><style face="normal" font="default" size="100%">Taran, T V</style></author><author><style face="normal" font="default" size="100%">Taran, A V</style></author><author><style face="normal" font="default" size="100%">Ismailova, G K</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Emergencies, which worse epidemiological situation].</style></title><secondary-title><style face="normal" font="default" size="100%">Zhurnal mikrobiologii, epidemiologii, i immunobiologii</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Zh. Mikrobiol. Epidemiol. Immunobiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Nov-Dec</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">27-32</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099392?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Riapis, L A</style></author><author><style face="normal" font="default" size="100%">Briko, N I</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Epidemiological surveillance and policy of specific prophylaxis of invasive pneumococcal infections in Russia].</style></title><secondary-title><style face="normal" font="default" size="100%">Zhurnal mikrobiologii, epidemiologii, i immunobiologii</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Zh. Mikrobiol. Epidemiol. Immunobiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Nov-Dec</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">112-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Literature data on contemporary state of specific prophylaxis of invasive pneumococcal infections in Russia and abroad are summarized in the review. Main advantages and disadvantages of existing polysaccharide and conjugated vaccines are discussed. Main routes for epidemiologic surveillance for invasive pneumococcal infections which will promote improvement of analytic, diagnostic and management activities of specialists from Federal Service on Surveillance for Protection of Consumers Rights and Human Welfare are proposed. Recommendations on assessment of invasive pneumococcal disease burden as well as on policy of its prevention are provided.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099398?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Taran, A V</style></author><author><style face="normal" font="default" size="100%">Kochieva, M M</style></author><author><style face="normal" font="default" size="100%">Evchenko, Iu M</style></author><author><style face="normal" font="default" size="100%">Kulichenko, A N</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Measures for rabies control in Republic of South Ossetia during emergency situation].</style></title><secondary-title><style face="normal" font="default" size="100%">Zhurnal mikrobiologii, epidemiologii, i immunobiologii</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Zh. Mikrobiol. Epidemiol. Immunobiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Nov-Dec</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">54-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099395?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Men'shikov, D D</style></author><author><style face="normal" font="default" size="100%">Godkov, M A</style></author><author><style face="normal" font="default" size="100%">Chernen'kaia, T V</style></author><author><style face="normal" font="default" size="100%">Kiselevskaia-Babinina, I V</style></author><author><style face="normal" font="default" size="100%">Semenova, A V</style></author><author><style face="normal" font="default" size="100%">Men'shikova, E D</style></author><author><style face="normal" font="default" size="100%">Kurilin, B L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Mono- and associated microflora during wound infection in patients with burns].</style></title><secondary-title><style face="normal" font="default" size="100%">Zhurnal mikrobiologii, epidemiologii, i immunobiologii</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Zh. Mikrobiol. Epidemiol. Immunobiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Nov-Dec</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">3-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">To study etiologic role of microorganisms during wound infection and elucidation of their populations interaction in patientswith burns.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099390?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Onishchenko, G G</style></author><author><style face="normal" font="default" size="100%">Kulichenko, A N</style></author><author><style face="normal" font="default" size="100%">Evchenko, Iu M</style></author><author><style face="normal" font="default" size="100%">Tikhenko, N I</style></author><author><style face="normal" font="default" size="100%">Grizhebovskiĭ, G M</style></author><author><style face="normal" font="default" size="100%">Beĭer, A P</style></author><author><style face="normal" font="default" size="100%">Agapitov, D S</style></author><author><style face="normal" font="default" size="100%">Kochieva, M M</style></author><author><style face="normal" font="default" size="100%">Kabulova, B A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Preventive and anti-epidemic measures against acute intestinal infections in the Republic of South Ossetia during liquidation of humanitarian catastrophe consequences].</style></title><secondary-title><style face="normal" font="default" size="100%">Zhurnal mikrobiologii, epidemiologii, i immunobiologii</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Zh. Mikrobiol. Epidemiol. Immunobiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Nov-Dec</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">47-51</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099394?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Butaev, T M</style></author><author><style face="normal" font="default" size="100%">Gadzieva, G K</style></author><author><style face="normal" font="default" size="100%">Merkulova, N A</style></author><author><style face="normal" font="default" size="100%">Otaraeva, N I</style></author><author><style face="normal" font="default" size="100%">Tsarikaeva, M S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Realization of action plan on sanitary and anti-epidemic services for population of the Republic of South Ossetia during emergency situation].</style></title><secondary-title><style face="normal" font="default" size="100%">Zhurnal mikrobiologii, epidemiologii, i immunobiologii</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Zh. Mikrobiol. Epidemiol. Immunobiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Nov-Dec</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">43-4</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099393?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Egorin, Merrill J</style></author><author><style face="normal" font="default" size="100%">Mauro, Michael J</style></author><author><style face="normal" font="default" size="100%">Trent, Jonathan C</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Drug plasma monitoring in CML and GIST: A case-based discussion.</style></title><secondary-title><style face="normal" font="default" size="100%">Clinical advances in hematology &amp; oncology : H&amp;O</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Clin Adv Hematol Oncol</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">7</style></volume><pages><style face="normal" font="default" size="100%">S1, S3-11</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Drug plasma monitoring has emerged as an important tool to obtain optimal levels of a particular drug among individual patients. Plasma monitoring of imatinib levels would appear to be practical in cases where there is lack of response, heightened toxicity, or evidence of poor adherence to therapy. However, the potential role of monitoring plasma drug concentrations in guiding treatment decisions and optimizing patient therapy has yet to be established. Currently, there are no clinical recommendations regarding how to incorporate imatinib drug plasma monitoring in patients with either chronic myeloid leukemia or gastrointestinal stromal tumors, indications for which imatinib is approved. Here, the latest research and evidence regarding imatinib drug plasma monitoring is discussed. Three cases are presented to illustrate the most common examples where monitoring imatinib plasma concentrations may help to guide treatment decisions. These cases include a suboptimal response to imatinib treatment, lack of patient adherence to imatinib, and imatinib-related toxicity. By understanding the potential role of monitoring plasma imatinib concentrations in patients with chronic myeloid leukemia or gastrointestinal stromal tumors, physicians can identify patients who may benefit from drug plasma monitoring and consider incorporating the data in order to improve patient outcomes.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099379?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wilkins, Olivia</style></author><author><style face="normal" font="default" size="100%">Waldron, Levi</style></author><author><style face="normal" font="default" size="100%">Nahal, Hardeep</style></author><author><style face="normal" font="default" size="100%">Provart, Nicholas J</style></author><author><style face="normal" font="default" size="100%">Campbell, Malcolm M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genotype and time of day shape the Populus drought response.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">60</style></volume><pages><style face="normal" font="default" size="100%">703-15</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">As exposure to episodic drought can impinge significantly on forest health and the establishment of productive tree plantations, there is great interest in understanding the mechanisms of drought response in trees. The ecologically dominant and economically important genus Populus, with its sequenced genome, provides an ideal opportunity to examine transcriptome level changes in trees in response to a drought stimulus. The transcriptome level drought response of two commercially important Populus clones (P. deltoides x P. nigra, DN34, and P. nigra x P. maximowiczii, NM6) was characterized over a diurnal period using a 4 x 2 x 2 complete randomized factorial anova experimental design (four time points, two genotypes and two treatment conditions), using Affymetrix Poplar GeneChip microarrays. Notably, the specific genes that exhibited changes in transcript abundance in response to drought differed between the genotypes and/or the time of day that they exhibited their greatest differences. This study emphasizes the fact that it is not possible to draw simple, generalized conclusions about the drought response of the genus Populus on the basis of one species, nor on the basis of results collected at a single time point. The data derived from our studies provide insights into the variety of genetic mechanisms underpinning the Populus drought response, and provide candidates for future experiments aimed at understanding this response across this economically and ecologically important genus.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19682285?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Chu, Yanguang</style></author><author><style face="normal" font="default" size="100%">Su, Xiaohua</style></author><author><style face="normal" font="default" size="100%">Huang, Qinjun</style></author><author><style face="normal" font="default" size="100%">Zhang, Xianghua</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Patterns of DNA sequence variation at candidate gene loci in black poplar (Populus nigra L.) as revealed by single nucleotide polymorphisms.</style></title><secondary-title><style face="normal" font="default" size="100%">Genetica</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Genetica</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">137</style></volume><pages><style face="normal" font="default" size="100%">141-50</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Black poplar (Populus nigra L.) is an economically and ecologically important tree species and an ideal organism for studies of genetic variation. In the present work, we use a candidate gene approach to infer the patterns of DNA variation in natural populations of this species. A total of 312 single nucleotide polymorphisms (SNPs) are found among 8,056 bp sequenced from nine drought-adaptation and photosynthesis-related gene loci. The median SNP frequency is one site per 26 bp. The average nucleotide diversity is calculated to be theta(W) = 0.01074 and pi(T) = 0.00702, higher values than those observed in P. tremula, P. trichocarpa and most conifer species. Tests of neutrality for each gene reveal a general excess of low-frequency mutations, a greater number of haplotypes than expected and an excess of high-frequency derived variants in P. nigra, which is consistent with previous findings that genetic hitchhiking has occurred in this species. Linkage disequilibrium is low, decaying rapidly from 0.45 to 0.20 or less within a distance of 300 bp, although the declines of r(2) are variable among different loci. This is similar to the rate of decay reported in most other tree species. Our dataset is expected to enhance understanding of how evolutionary forces shape genetic variation, and it will contribute to molecular breeding in black poplar.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19484494?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lee, Chanhui</style></author><author><style face="normal" font="default" size="100%">Teng, Quincy</style></author><author><style face="normal" font="default" size="100%">Huang, Wenlin</style></author><author><style face="normal" font="default" size="100%">Zhong, Ruiqin</style></author><author><style face="normal" font="default" size="100%">Ye, Zheng-Hua</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The poplar GT8E and GT8F glycosyltransferases are functional orthologs of Arabidopsis PARVUS involved in glucuronoxylan biosynthesis.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant &amp; cell physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">50</style></volume><pages><style face="normal" font="default" size="100%">1982-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The poplar GT8E and GT8F glycosyltransferases have previously been shown to be associated with wood formation, but their roles in the biosynthesis of wood components are not known. Here, we show that PoGT8E and PoGT8F are expressed in vessels and fibers during wood formation and their encoded proteins are predominantly located in the endoplasmic reticulum. We demonstrate that expression of PoGT8E and PoGT8F in the Arabidopsis parvus mutant rescues the defects in the content and structure of glucuronoxylan conferred by the parvus mutation. These findings suggest that PoGT8E and PoGT8F are involved in glucuronoxylan biosynthesis during wood formation in poplar.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19789274?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Holeski, Liza M</style></author><author><style face="normal" font="default" size="100%">Kearsley, Michael J C</style></author><author><style face="normal" font="default" size="100%">Whitham, Thomas G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Separating ontogenetic and environmental determination of resistance to herbivory in cottonwood.</style></title><secondary-title><style face="normal" font="default" size="100%">Ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ecology</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">90</style></volume><pages><style face="normal" font="default" size="100%">2969-73</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We used narrowleaf cottonwood, Populus angustifolia, and the gall-forming aphid, Pemphigus betae, to determine the extent to which ontogenetic variation in resistance to herbivory is due to endogenous, stable genetic influences. In a three-year common garden trial using ramets propagated from the top, middle, and bottom of mature trees, we found that the resistance of trees to aphids was significantly higher in top vs. bottom source ramets, supporting the hypothesis of a stable, genetically programmed component to aphid resistance. The magnitude of ontogenetically based variation in resistance within an individual tree is comparable to the genetic variation in resistance among narrowleaf cottonwood genotypes or populations found in other studies. These ontogenetic-based findings have the potential to alter ecological interactions and evolutionary trajectories of plant-herbivore interactions.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19967853?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kalluri, Udaya C</style></author><author><style face="normal" font="default" size="100%">Hurst, Gregory B</style></author><author><style face="normal" font="default" size="100%">Lankford, Patricia K</style></author><author><style face="normal" font="default" size="100%">Ranjan, Priya</style></author><author><style face="normal" font="default" size="100%">Pelletier, Dale A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Shotgun proteome profile of Populus developing xylem.</style></title><secondary-title><style face="normal" font="default" size="100%">Proteomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Proteomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">4871-80</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Understanding the molecular pathways of plant cell wall biosynthesis and remodeling is central to interpreting biological mechanisms underlying plant growth and adaptation as well as leveraging that knowledge towards development of improved bioenergy feedstocks. Here, we report the application of shotgun MS/MS profiling to the proteome of Populus developing xylem. Nearly 6000 different proteins were identified from the xylem proteome. To identify low-abundance DNA-regulatory proteins from the developing xylem, a selective nuclear proteome profiling method was developed. Several putative transcription factors and chromatin remodeling proteins were identified using this method, such as NAC domain, CtCP-like and CHB3-SWI/SNF-related proteins. Public databases were mined to obtain information in support of subcellular localization, transcript-level expression and functional categorization of identified proteins. In addition to finding protein-level evidence of candidate cell wall biosynthesis genes from xylem (wood) tissue such as cellulose synthase, sucrose synthase and polygalacturonase, several other potentially new candidate genes in the cell wall biosynthesis pathway were discovered. Further application of such proteomics methods will aid in plant systems biology modeling efforts by enhancing the understanding not only of cell wall biosynthesis but also of other plant developmental and physiological pathways.</style></abstract><issue><style face="normal" font="default" size="100%">21</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19743414?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Talhelm, Alan F</style></author><author><style face="normal" font="default" size="100%">Pregitzer, Kurt S</style></author><author><style face="normal" font="default" size="100%">Zak, Donald R</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Species-specific responses to atmospheric carbon dioxide and tropospheric ozone mediate changes in soil carbon.</style></title><secondary-title><style face="normal" font="default" size="100%">Ecology letters</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ecol. Lett.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">12</style></volume><pages><style face="normal" font="default" size="100%">1219-28</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We repeatedly sampled the surface mineral soil (0-20 cm depth) in three northern temperate forest communities over an 11-year experimental fumigation to understand the effects of elevated carbon dioxide (CO(2)) and/or elevated phyto-toxic ozone (O(3)) on soil carbon (C). After 11 years, there was no significant main effect of CO(2) or O(3) on soil C. However, within the community containing only aspen (Populus tremuloides Michx.), elevated CO(2) caused a significant decrease in soil C content. Together with the observations of increased litter inputs, this result strongly suggests accelerated decomposition under elevated CO(2.) In addition, an initial reduction in the formation of new (fumigation-derived) soil C by O(3) under elevated CO(2) proved to be only a temporary effect, mirroring trends in fine root biomass. Our results contradict predictions of increased soil C under elevated CO(2) and decreased soil C under elevated O(3) and should be considered in models simulating the effects of Earth's altered atmosphere.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19754884?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kumar, Rajeev</style></author><author><style face="normal" font="default" size="100%">Wyman, Charles E</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Access of cellulase to cellulose and lignin for poplar solids produced by leading pretreatment technologies.</style></title><secondary-title><style face="normal" font="default" size="100%">Biotechnology progress</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biotechnol. Prog.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May-Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">25</style></volume><pages><style face="normal" font="default" size="100%">807-19</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Adsorption of cellulase on solids resulting from pretreatment of poplar wood by ammonia fiber expansion (AFEX), ammonia recycled percolation (ARP), controlled pH, dilute acid (DA), flowthrough (FT), lime, and sulfur dioxide (SO(2)) and pure Avicel glucan was measured at 4 degrees C, as were adsorption and desorption of cellulase and adsorption of beta-glucosidase for lignin left after enzymatic digestion of the solids from these pretreatments. From this, Langmuir adsorption parameters, cellulose accessibility to cellulase, and the effectiveness of cellulase adsorbed on poplar solids were estimated, and the effect of delignification on cellulase effectiveness was determined. Furthermore, Avicel hydrolysis inhibition by enzymatic and acid lignin of poplar solids was studied. Flowthrough pretreated solids showed the highest maximum cellulase adsorption capacity (sigma(solids) = 195 mg/g solid) followed by dilute acid (sigma(solids) = 170.0 mg/g solid) and lime pretreated solids (sigma(solids) = 150.8 mg/g solid), whereas controlled pH pretreated solids had the lowest (sigma(solids) = 56 mg/g solid). Lime pretreated solids also had the highest cellulose accessibility (sigma(cellulose) = 241 mg/g cellulose) followed by FT and DA. AFEX lignin had the lowest cellulase adsorption capacity (sigma(lignin) = 57 mg/g lignin) followed by dilute acid lignin (sigma(lignin) = 74 mg/g lignin). AFEX lignin also had the lowest beta-glucosidase capacity (sigma(lignin) = 66.6 mg/g lignin), while lignin from SO(2) (sigma(lignin) = 320 mg/g lignin) followed by dilute acid had the highest (301 mg/g lignin). Furthermore, SO(2) followed by dilute acid pretreated solids gave the highest cellulase effectiveness, but delignification enhanced cellulase effectiveness more for high pH than low pH pretreatments, suggesting that lignin impedes access of enzymes to xylan more than to glucan, which in turn affects glucan accessibility. In addition, lignin from enzymatic digestion of AFEX and dilute acid pretreated solids inhibited Avicel hydrolysis less than ARP and flowthrough lignin, whereas acid lignin from unpretreated poplar inhibited enzymes the most. Irreversible binding of cellulase to lignin varied with pretreatment type and desorption method.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19504581?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Renaut, Jenny</style></author><author><style face="normal" font="default" size="100%">Bohler, Sacha</style></author><author><style face="normal" font="default" size="100%">Hausman, Jean-François</style></author><author><style face="normal" font="default" size="100%">Hoffmann, Lucien</style></author><author><style face="normal" font="default" size="100%">Sergeant, Kjell</style></author><author><style face="normal" font="default" size="100%">Ahsan, Nagib</style></author><author><style face="normal" font="default" size="100%">Jolivet, Yves</style></author><author><style face="normal" font="default" size="100%">Dizengremel, Pierre</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The impact of atmospheric composition on plants: a case study of ozone and poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Mass spectrometry reviews</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mass Spectrom Rev</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May-Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">495-516</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Tropospheric ozone is the main atmospheric pollutant that causes damages to trees. The estimation of the threshold for ozone risk assessment depends on the evaluation of the means that this pollutant impacts the plant and, especially, the foliar organs. The available results show that, before any visible symptom appears, carbon assimilation and the underlying metabolic processes are decreased under chronic ozone exposure. By contrast, the catabolic pathways are enhanced, and contribute to the supply of sufficient reducing power necessary to feed the detoxification processes. Reactive oxygen species delivered during ozone exposure serve as toxic compounds and messengers for the signaling system. In this review, we show that the contribution of genomic tools (transcriptomics, proteomics, and metabolomics) for a better understanding of the mechanistic cellular responses to ozone largely relies on spectrometric measurements.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18985755?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Pauchet, Yannick</style></author><author><style face="normal" font="default" size="100%">Wilkinson, Paul</style></author><author><style face="normal" font="default" size="100%">van Munster, Manuella</style></author><author><style face="normal" font="default" size="100%">Augustin, Sylvie</style></author><author><style face="normal" font="default" size="100%">Pauron, David</style></author><author><style face="normal" font="default" size="100%">ffrench-Constant, Richard H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Pyrosequencing of the midgut transcriptome of the poplar leaf beetle Chrysomela tremulae reveals new gene families in Coleoptera.</style></title><secondary-title><style face="normal" font="default" size="100%">Insect biochemistry and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Insect Biochem. Mol. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May-Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">39</style></volume><pages><style face="normal" font="default" size="100%">403-13</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The insect midgut is the primary target site for Bt-derived insecticides and Bt alternatives. However, despite extensive recent study, the precise role and nature of different Bt receptors remains a subject of considerable debate. This problem is fuelled by a lack of understanding of the genes expressed in the insect midgut and their physiological roles. The poplar leaf beetle, Chrysomela tremulae, is an important model for understanding the mode of action of, and resistance to, coleopteran-specific Bt toxins and currently shows the only known naturally occurring case of resistance to Cry3A toxins. Moreover it belongs to the same family as the corn rootworm, Diabrotica virgifera, an economically important beetle pest and target of hybrid corn expressing Cry3 toxins. Pyrosequencing is a fast and efficient way of defining the transcriptome of specific insect tissues such as the larval midgut. Here we use 454 based pyrosequencing to sample the larval midgut transcriptome of C. tremulae. We identify candidate genes of putative Bt receptors including transcripts encoding cadherin-like proteins, aminopeptidase N and alkaline phosphatase. We also describe a wealth of new transcripts predicting rapidly evolving gene families involved in plant tissue digestion, which have no homologs in the genome of the stored product pest the Red Flour beetle, Tribolium castaneum.</style></abstract><issue><style face="normal" font="default" size="100%">5-6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19364528?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Christova, Petya K</style></author><author><style face="normal" font="default" size="100%">Donchev, Anthony A</style></author><author><style face="normal" font="default" size="100%">Shosheva, Alexandra C</style></author><author><style face="normal" font="default" size="100%">Getov, Vladimir I</style></author><author><style face="normal" font="default" size="100%">Dimitrov, Mitko I</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Some physicochemical peculiarities of poplar plastocyanins a and b.</style></title><secondary-title><style face="normal" font="default" size="100%">Zeitschrift für Naturforschung. C, Journal of biosciences</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Z. Naturforsch., C, J. Biosci.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May-Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">64</style></volume><pages><style face="normal" font="default" size="100%">399-404</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The redox potentials of poplar plastocyanins a and b (PCa, PCb) were determined by spectrophotometric titrations of their reduced forms with [Fe(CN)6]3-. It was found that the two isoforms have the following millimolar extinction coefficients epsilon597 equilibrium constants Keq of one-electron exchange with [Fe(CN)6]4-/[Fe(CN)6]3-, and standard electron potentials E0: PCa: epsilon597 = (4.72 +/- 0.08) mM(-1) cm(-1), Keq = 0.133 +/- 0.009, E0' = (354 +/- 11) mV; PCb: epsilon597 = (5.23 +/- 0.16) mM(-1) cm(-1), Keq = 0.175 +/- 0.010, E0' = (363 +/- 12) mV. The pH dependence of the redox potential of PCb was studied too. It was found, that the value of E0' for PCb is constant in the pH range 6.5-9.5, but decreases in the range 4.8-6.5. On the whole, the dependence resembles that of PC from some well-known plant species, including poplar PCa. The changes of E0' in the pH-dependent region for poplar PCb, however, are smaller and are 13 mV per pH unit, whereas in the other well-known plant species the changes are about 50-60 mV per pH unit. It has been assumed that the weaker pH dependence of EO' of PCb accounts for some structural differences between PCa and PCb.</style></abstract><issue><style face="normal" font="default" size="100%">5-6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19678546?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lv, Xiaomeng</style></author><author><style face="normal" font="default" size="100%">Song, Xiaodan</style></author><author><style face="normal" font="default" size="100%">Rao, Guodong</style></author><author><style face="normal" font="default" size="100%">Pan, Xiang</style></author><author><style face="normal" font="default" size="100%">Guan, Liping</style></author><author><style face="normal" font="default" size="100%">Jiang, Xiangning</style></author><author><style face="normal" font="default" size="100%">Lu, Hai</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Construction vascular-specific expression bi-directional promoters in plants.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of biotechnology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Biotechnol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May 20</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">141</style></volume><pages><style face="normal" font="default" size="100%">104-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Promoters that have been widely used for both basic research and biotechnological application in plants are generally unidirectional. Here we describe a strategy to bi-directionalize the vascular-specific expression grp1.8 promoter (here named GRPp) and 4CL1 promoter (here named 4CL1p) so that one promoter can direct the vascular-specific expression of two genes, one on each end of the promoter. The minimal promoter (35Smini or GRP mini), when fused at the 5' end of the specific expression promoter (GRPp or 4CL1p) to form bi-directional promoter (35Smini-GRPp, 35Smini-4CL1p or GRPmini-GRPp), was able to direct expression of the glucuronidase (gus) and green fluorescent protein (gfp) gene in all independent transgenic tobacco lines. Stable expression of gusA and gfp genes in transgenic plants was analyzed by histochemical staining for GUS and fluorescence microscopic observation under UV for GFP in transgenic plants. The remarkable transcript levels of GFP and GUS were detected by real-time PCR in independent transgenic tobacco lines. Their vascular-specific bi-directional promoters should be used to vascular-specific expression several functional genes in transgenic plants simultaneously.</style></abstract><issue><style face="normal" font="default" size="100%">3-4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19433212?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Dafoe, Nicole J</style></author><author><style face="normal" font="default" size="100%">Zamani, Arezoo</style></author><author><style face="normal" font="default" size="100%">Ekramoddoullah, Abul K M</style></author><author><style face="normal" font="default" size="100%">Lippert, Dustin</style></author><author><style face="normal" font="default" size="100%">Bohlmann, Jörg</style></author><author><style face="normal" font="default" size="100%">Constabel, C Peter</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Analysis of the poplar phloem proteome and its response to leaf wounding.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of proteome research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Proteome Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">8</style></volume><pages><style face="normal" font="default" size="100%">2341-50</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Phloem exudate collected from hybrid poplar (Populus trichocarpa x Populus deltoides) was estimated to have more than 100 proteins, of which 48 were identified using LC-MS/MS. Comparative two-dimensional gel electrophoresis demonstrated that two phloem exudate proteins were significantly (P&lt;0.05) upregulated 24 h after leaf wounding. These were identified as pop3/SP1 and a thaumatin-like protein. This is the first characterization of a phloem proteome from a tree species.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19245218?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">El-Gendy, Ahmed S</style></author><author><style face="normal" font="default" size="100%">Svingos, Sotero</style></author><author><style face="normal" font="default" size="100%">Brice, Donald</style></author><author><style face="normal" font="default" size="100%">Garretson, Joel H</style></author><author><style face="normal" font="default" size="100%">Schnoor, Jerald</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Assessments of the efficacy of a long-term application of a phytoremediation system using hybrid poplar trees at former oil tank farm sites.</style></title><secondary-title><style face="normal" font="default" size="100%">Water environment research : a research publication of the Water Environment Federation</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Water Environ. Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">81</style></volume><pages><style face="normal" font="default" size="100%">486-98</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A poplar tree-phytoremediation system was installed at former refinery and tank farm sites in Cabin Creek, West Virginia, to cleanup petroleum-contaminated-soils and groundwater. Groundwater and soils in both sites were sampled and analyzed on a regular basis to monitor changes in contaminant concentration since 1999. The concentration of benzene, toluene, ethylbenzene, xylene, and gasoline range organics (GRO) decreased an average of 81%, 90%, 67%, 78%, and 82%, respectively, in the lower soil horizons and 34%, 84%, 12%, 19%, and 59%, respectively, in groundwater. In addition, concentrations of oxygen, methane, and carbon dioxide in soil gas demonstrated that tree roots dewatered soils and allowed penetration of oxygen deep into the soil profile, creating necessary conditions for rhizosphere bioremediation. Although required clean-up time can limit phytoremediation, it has proven to be a cost-effective strategy for site improvement if imminent pathways for human exposure and risk are not an issue.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19472940?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Brilli, Federico</style></author><author><style face="normal" font="default" size="100%">Ciccioli, Paolo</style></author><author><style face="normal" font="default" size="100%">Frattoni, Massimiliano</style></author><author><style face="normal" font="default" size="100%">Prestininzi, Marco</style></author><author><style face="normal" font="default" size="100%">Spanedda, Antonio Franco</style></author><author><style face="normal" font="default" size="100%">Loreto, Francesco</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Constitutive and herbivore-induced monoterpenes emitted by Populus x euroamericana leaves are key volatiles that orient Chrysomela populi beetles.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">32</style></volume><pages><style face="normal" font="default" size="100%">542-52</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Chrysomela populi beetles feed on poplar leaves and extensively damage plantations. We investigated whether olfactory cues orientate landing and feeding. Young, unexpanded leaves of hybrid poplar emit constitutively a blend of monoterpenes, primarily (E)-beta-ocimene and linalool. This blend attracts inexperienced adults of C. populi that were not previously fed with poplar leaves. In mature leaves constitutively emitting isoprene, insect attack induces biosynthesis and emission of the same blend of monoterpenes, but in larger amount than in young leaves. The olfactometric test indicates that inexperienced beetles are more attracted by adult than by young attacked leaves, suggesting that attraction by induced monoterpenes is dose dependent. The blend does not attract adults that previously fed on poplar leaves. Insect-induced emission of monoterpenes peaks 4 d after the attack, and is also detected in non-attacked leaves. Induced monoterpene emission is associated in mature leaves with a larger decrease of isoprene emission. The reduction of isoprene emission is faster than photosynthesis reduction in attacked leaves, and also occurs in non-attacked leaves. Insect-induced monoterpenes are quickly and completely labelled by 13C. It is speculated that photosynthetic carbon preferentially allocated to constitutive isoprene in healthy leaves is in part diverted to induced monoterpenes after the insect attack.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19183286?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">McDonnell, Lisa</style></author><author><style face="normal" font="default" size="100%">Plett, Jonathan M</style></author><author><style face="normal" font="default" size="100%">Andersson-Gunnerås, Sara</style></author><author><style face="normal" font="default" size="100%">Kozela, Christopher</style></author><author><style face="normal" font="default" size="100%">Dugardeyn, Jasper</style></author><author><style face="normal" font="default" size="100%">Van Der Straeten, Dominique</style></author><author><style face="normal" font="default" size="100%">Glick, Bernard R</style></author><author><style face="normal" font="default" size="100%">Sundberg, Björn</style></author><author><style face="normal" font="default" size="100%">Regan, Sharon</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Ethylene levels are regulated by a plant encoded 1-aminocyclopropane-1-carboxylic acid deaminase.</style></title><secondary-title><style face="normal" font="default" size="100%">Physiologia plantarum</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Physiol Plant</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">136</style></volume><pages><style face="normal" font="default" size="100%">94-109</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Control of the levels of the plant hormone ethylene is crucial in the regulation of many developmental processes and stress responses. Ethylene production can be controlled by altering endogenous levels of 1-aminocyclopropane-1-carboxylic acid (ACC), the immediate precursor to ethylene or by altering its conversion to ethylene. ACC is known to be irreversibly broken down by bacterial or fungal ACC deaminases (ACDs). Sequence analysis revealed two putative ACD genes encoded for in the genome of Arabidopsis thaliana (A. thaliana) and we detected ACD activity in plant extracts. Expression of one of these A. thaliana genes (AtACD1) in bacteria indicated that it had ACD activity. Moreover, transgenic plants harboring antisense constructs of the gene decreased ACD activity to 70% of wild-type (WT) levels, displayed an increased sensitivity to ACC and produced significantly more ethylene. Taken together, these results show that AtACD1 can act as a regulator of ACC levels in A. thaliana.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19508369?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Madritch, Michael D</style></author><author><style face="normal" font="default" size="100%">Greene, Samantha L</style></author><author><style face="normal" font="default" size="100%">Lindroth, Richard L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genetic mosaics of ecosystem functioning across aspen-dominated landscapes.</style></title><secondary-title><style face="normal" font="default" size="100%">Oecologia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Oecologia</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">160</style></volume><pages><style face="normal" font="default" size="100%">119-27</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Genetic diversity is the foundation of all biodiversity, and the genetic variation within species is increasingly recognized as being important to ecosystem level processes. Recent research demonstrates that plant genotype influences above- and belowground communities as well as basic ecosystem functions. However, the extent to which plant genotypes create spatial mosaics of genetically mediated ecosystem processes in natural forests is uncertain. We use Populus tremuloides as a model system to demonstrate the importance of plant genotype on carbon and nitrogen cycling in natural systems. We identified 24 distinct P. tremuloides clones with multiple ramets across 25 km(2) in southern Wisconsin, United States, using microsatellite makers. We then sampled clone leaf chemistry and belowground nutrient content and microbial extracellular enzyme activity. Aspen-induced variation in belowground carbon and nitrogen content, and microbial activity, varied widely among clones. Variation in green leaf chemistry and belowground microbial activity were correlated with genetic distance among clones, such that more genetically distant clones created more divergent patches of ecosystem processes. These data suggest that aspen genotypes create spatial mosaics of genetically mediated ecosystem functioning across natural landscapes and can therefore have evolutionary consequences for co-occurring species.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19214586?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bonhomme, Ludovic</style></author><author><style face="normal" font="default" size="100%">Monclus, Romain</style></author><author><style face="normal" font="default" size="100%">Vincent, Delphine</style></author><author><style face="normal" font="default" size="100%">Carpin, Sabine</style></author><author><style face="normal" font="default" size="100%">Claverol, Stéphane</style></author><author><style face="normal" font="default" size="100%">Lomenech, Anne-Marie</style></author><author><style face="normal" font="default" size="100%">Labas, Valérie</style></author><author><style face="normal" font="default" size="100%">Plomion, Christophe</style></author><author><style face="normal" font="default" size="100%">Brignolas, Franck</style></author><author><style face="normal" font="default" size="100%">Morabito, Domenico</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genetic variation and drought response in two Populus x euramericana genotypes through 2-DE proteomic analysis of leaves from field and glasshouse cultivated plants.</style></title><secondary-title><style face="normal" font="default" size="100%">Phytochemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Phytochemistry</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">70</style></volume><pages><style face="normal" font="default" size="100%">988-1002</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Genotype and water deficit effects on leaf 2-DE protein profiles of two Populus deltoides x Populus nigra, cv. 'Agathe_F' and 'Cima', were analysed over a short-term period of 18 days in glasshouse using 4-month-old rooted cuttings and over a long-lasting period of 86 days in open field using 4-year-old rooted cuttings. Leaf proteomes were analyzed using two-dimensional gel electrophoresis, and proteins were identified after database searching from MS peptide spectra. A reliable genotype effect was observed in the leaf proteome over experiment locations, water regimes and sampling dates. Quantitative differences between genotypes were found. Most of them corresponded to proteins matching isoforms or post-translational modification variants. However, 'Cima' displayed the highest abundance of antioxidant enzymes. In response to water deficit, about 10% of the reproducible spots significantly varied regardless of the experiment location, among which about 25% also displayed genotype-dependent variations. As a whole, while 'Cima' differed from 'Agathe_F' by increased abundance of enzymes involved in photorespiration and in oxidative stress, 'Agathe_F' was mainly differentiated by increased abundance of enzymes involved in photosynthesis.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19560791?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Yang, Xiaohan</style></author><author><style face="normal" font="default" size="100%">Jawdy, Sara</style></author><author><style face="normal" font="default" size="100%">Tschaplinski, Timothy J</style></author><author><style face="normal" font="default" size="100%">Tuskan, Gerald A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genome-wide identification of lineage-specific genes in Arabidopsis, Oryza and Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">Genomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">93</style></volume><pages><style face="normal" font="default" size="100%">473-80</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Protein sequences were compared among Arabidopsis, Oryza and Populus to identify differential gene (DG) sets that are in one but not the other two genomes. The DG sets were screened against a plant transcript database, the NR protein database and six newly-sequenced genomes (Carica, Glycine, Medicago, Sorghum, Vitis and Zea) to identify a set of species-specific genes (SS). Gene expression, protein motif and intron number were examined. 165, 638 and 109 SS genes were identified in Arabidopsis, Oryza and Populus, respectively. Some SS genes were preferentially expressed in flowers, roots, xylem and cambium or up-regulated by stress. Six conserved motifs in Arabidopsis and OryzaSS proteins were found in other distant lineages. The SS gene sets were enriched with intronless genes. The results reflect functional and/or anatomical differences between monocots and eudicots or between herbaceous and woody plants. The Populus-specific genes are candidates for carbon sequestration and biofuel research.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19442640?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Dafoe, Nicole J</style></author><author><style face="normal" font="default" size="100%">Constabel, C Peter</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Proteomic analysis of hybrid poplar xylem sap.</style></title><secondary-title><style face="normal" font="default" size="100%">Phytochemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Phytochemistry</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">70</style></volume><pages><style face="normal" font="default" size="100%">856-63</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Xylem sap collected from Populus trichocarpaxPopulus deltoides using root pressure was estimated to contain more than 100 proteins. Ninety-seven of these proteins were identified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). These proteins were classified into 10 functional categories including metabolism, signaling, stress response and cell wall functions. The majority of xylem sap proteins were metabolic enzymes involved in processes including translation, proteolysis, and glycolysis. Stress-related proteins were also prevalent. In contrast to xylem sap proteins collected from annual plants, the majority of poplar xylem sap proteins do not appear to be classically secreted since only 33 proteins were predicted to have an N-terminal signal peptide targeting them to the secretory pathway. Of the remaining 64 proteins, 27 were predicted to be secreted non-classically. While a number of proteins identified here have been previously reported in xylem sap proteomes of annual plants, many xylem sap proteins were identified in poplar which may reflect functions specific to perennial plants.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19467552?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Robinson, Andrew R</style></author><author><style face="normal" font="default" size="100%">Mansfield, Shawn D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Rapid analysis of poplar lignin monomer composition by a streamlined thioacidolysis procedure and near-infrared reflectance-based prediction modeling.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">58</style></volume><pages><style face="normal" font="default" size="100%">706-14</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Determination of the physico-chemical attributes of plant cell walls, such as lignin content and composition, is of paramount importance in germplasm screening and for evaluating the results of plant breeding and genetic engineering. There are escalating needs for analyses to be robust, reproducible, accurate, and efficient. We have recently modified an established protocol for discrimination of lignin monomers, thioacidolysis, with the goal of increasing sample throughput while maintaining accuracy and reducing equipment load and consumption of reagents. Numerous methodological changes related to volume scaling, selection of the processing vessel, and sample handling were addressed. The revised protocol permitted rapid processing of some 50 or more samples per person per day. A direct comparison between methods using hybrid poplar (Populus alba x tremula) wood samples, resulted in quantities of p-hydroxyphenyl (H), guaiacyl (G), and syringyl (S) lignin monomers that were equivalent to those derived from the original protocol. The revised methodology was then applied to quickly generate phenotypic trait data from 267 hybrid poplar trees (including wild type and eight C4H::F5H transgenic lines), for the development of a near-infrared-based model for predicting the proportion of lignin monomers across a broad phenotypic range of S:G. The resulting partial least squares regression model performed well under full cross-validation, giving strong, linear relationships between actual and predicted monomer proportions, and very high predictive accuracy for the predominant G and S monomers. This research brings considerable refinement to the thioacidolysis procedure, and establishes a method for rapidly and accurately quantifying cell-wall lignin composition that could effectively be employed in routine phenotypic screening platforms.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19175772?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Behnke, Katja</style></author><author><style face="normal" font="default" size="100%">Kleist, Einhard</style></author><author><style face="normal" font="default" size="100%">Uerlings, Ricarda</style></author><author><style face="normal" font="default" size="100%">Wildt, Jürgen</style></author><author><style face="normal" font="default" size="100%">Rennenberg, Heinz</style></author><author><style face="normal" font="default" size="100%">Schnitzler, Jörg-Peter</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">RNAi-mediated suppression of isoprene biosynthesis in hybrid poplar impacts ozone tolerance.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">725-36</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Isoprene is the most abundant volatile compound emitted by vegetation. It influences air chemistry and is thought to take part in plant defense reactions against abiotic stress such as high temperature or ozone. However, whether or not isoprene emission impacts ozone tolerance of plants is still in discussion. In this study, we exploited the transgenic non-isoprene emitting grey poplar (Populus x canescens (Aiton) Sm.) in a biochemical and physiological model study to investigate the effect of acute ozone stress on the elicitation of defense-related emissions of plant volatiles, on photosynthesis and on the antioxidative system. We recorded that non-isoprene emitting poplars were more resistant to ozone as indicated by less damaged leaf area and higher assimilation rates compared to ozone-exposed wild-type (WT) plants. The integral of green leaf volatile emissions was different between the two poplar phenotypes and was a reliable early marker for subsequent leaf damage. For other stress-induced volatiles, such as mono-, homo- and sesquiterpenes and methyl salicylate, similar time profiles, pattern and emission intensities were observed in both transgenic and WT plants. However, unstressed non-isoprene emitting poplars are characterized by elevated levels of ascorbate and alpha-tocopherol as well as by a more effective de-epoxidation ratio of xanthophylls than the WT. Since ozone quenching properties of ascorbate are much higher than those of isoprene and furthermore alpha-tocopherol is also an essential antioxidant, non-isoprene emitting poplars might benefit from changes within the antioxidative system by providing them with enhanced ozone tolerance.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19324699?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kunkle, Justin M</style></author><author><style face="normal" font="default" size="100%">Walters, Michael B</style></author><author><style face="normal" font="default" size="100%">Kobe, Richard K</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Senescence-related changes in nitrogen in fine roots: mass loss affects estimation.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">715-23</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The fate of nitrogen (N) in senescing fine roots has broad implications for whole-plant N economies and ecosystem N cycling. Studies to date have generally shown negligible changes in fine root N per unit root mass during senescence. However, unmeasured loss of mobile non-N constituents during senescence could lead to underestimates of fine root N loss. For N fertilized and unfertilized potted seedlings of Populus tremuloides Michx., Acer rubrum L., Acer saccharum Marsh. and Betula alleghaniensis Britton, we predicted that the fine roots would lose mass and N during senescence. We estimated mass loss as the product of changes in root mass per length and root length between live and recently dead fine roots. Changes in root N were compared among treatments on uncorrected mass, length (which is independent of changes in mass per length), calcium (Ca) and corrected mass bases and by evaluating the relationships of dead root N as a function of live root N, species and fertilization treatments. Across species, from live to dead roots, mass decreased 28-40%, N uncorrected for mass loss increased 10-35%, N per length decreased 5-16%, N per Ca declined 14-48% and N corrected for mass declined 12-28%. Given the magnitude of senescence-related root mass loss and uncertainties about Ca dynamics in senescing roots, N loss corrected for mass loss is likely the most reliable estimate of N loss. We re-evaluated the published estimates of N changes during root senescence based on our values of mass loss and found an average of 28% lower N in dead roots than in fine roots. Despite uncertainty about the contributions of resorption, leaching and microbial immobilization to the net loss of N during root senescence, live root N was a strong and proportional predictor of dead root N across species and fertilization treatments, suggesting that live root N alone could be used to predict the contributions of senescing fine roots to whole-plant N economies and N cycling.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19203982?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Li, Jiebing</style></author><author><style face="normal" font="default" size="100%">Gellerstedt, Göran</style></author><author><style face="normal" font="default" size="100%">Toven, Kai</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Steam explosion lignins; their extraction, structure and potential as feedstock for biodiesel and chemicals.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioresource technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bioresour. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">100</style></volume><pages><style face="normal" font="default" size="100%">2556-61</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In the present study, a steam explosion wood pre-treatment process, optimized earlier with respect to ethanol production, has been applied to both softwoods (Picea abies and Pinus sylvestris) and hardwoods (Betula verrucosa and Populus tremula). The alkaline extractable lignins have then been isolated to investigate lignin separation efficiency and lignin structure and to evaluate their potential for producing value-added products, such as biodiesel components or chemicals, in terms of the purity, molecular size, functional groups, beta-O-4' inter-unit linkage content, and degradability in a subsequent processing treatment. The mechanism of lignin modification and possible improvements to the steam explosion pre-treatment process are discussed.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19157871?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kumar, Manoj</style></author><author><style face="normal" font="default" size="100%">Thammannagowda, Shivegowda</style></author><author><style face="normal" font="default" size="100%">Bulone, Vincent</style></author><author><style face="normal" font="default" size="100%">Chiang, Vincent</style></author><author><style face="normal" font="default" size="100%">Han, Kyung-Hwan</style></author><author><style face="normal" font="default" size="100%">Joshi, Chandrashekhar P</style></author><author><style face="normal" font="default" size="100%">Mansfield, Shawn D</style></author><author><style face="normal" font="default" size="100%">Mellerowicz, Ewa</style></author><author><style face="normal" font="default" size="100%">Sundberg, Björn</style></author><author><style face="normal" font="default" size="100%">Teeri, Tuula</style></author><author><style face="normal" font="default" size="100%">Ellis, Brian E</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">An update on the nomenclature for the cellulose synthase genes in Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">Trends in plant science</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Trends Plant Sci.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">14</style></volume><pages><style face="normal" font="default" size="100%">248-54</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Cellulose synthase (CesA) is a central catalyst in the generation of the plant cell wall biomass and is, therefore, the focus of intense research. Characterization of individual CesA genes from Populus species has led to the publication of several different naming conventions for CesA gene family members in this model tree. To help reduce the resulting confusion, we propose here a new phylogeny-based CesA nomenclature that aligns the Populus CesA gene family with the established Arabidopsis thaliana CesA family structure.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19375973?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gerosa, G</style></author><author><style face="normal" font="default" size="100%">Marzuoli, R</style></author><author><style face="normal" font="default" size="100%">Desotgiu, R</style></author><author><style face="normal" font="default" size="100%">Bussotti, F</style></author><author><style face="normal" font="default" size="100%">Ballarin-Denti, A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Validation of the stomatal flux approach for the assessment of ozone visible injury in young forest trees. Results from the TOP (transboundary ozone pollution) experiment at Curno, Italy.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">157</style></volume><pages><style face="normal" font="default" size="100%">1497-505</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">This paper summarises some of the main results of a two-year experiment carried out in an Open-Top Chambers facility in Northern Italy. Seedlings of Populus nigra, Fagus sylvatica, Quercus robur and Fraxinus excelsior have been subjected to different ozone treatments (charcoal-filtered and non-filtered air) and soil moisture regimes (irrigated and non-irrigated plots). Stomatal conductance models were applied and parameterised under South Alpine environmental conditions and stomatal ozone fluxes have been calculated. The flux-based approach provided a better performance than AOT40 in predicting the onset of foliar visible injuries. Critical flux levels, related to visible leaf injury, are proposed for P. nigra and F. sylvatica (ranging between 30 and 33 mmol O(3) m(-2)). Soil water stress delayed visible injury appearance and development by limiting ozone uptake. Data from charcoal-filtered treatments suggest the existence of an hourly flux threshold, below which may occur a complete ozone detoxification.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19019512?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wyman, Charles E</style></author><author><style face="normal" font="default" size="100%">Dale, Bruce E</style></author><author><style face="normal" font="default" size="100%">Elander, Richard T</style></author><author><style face="normal" font="default" size="100%">Holtzapple, Mark</style></author><author><style face="normal" font="default" size="100%">Ladisch, Michael R</style></author><author><style face="normal" font="default" size="100%">Lee, Y Y</style></author><author><style face="normal" font="default" size="100%">Mitchinson, Colin</style></author><author><style face="normal" font="default" size="100%">Saddler, John N</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Comparative sugar recovery and fermentation data following pretreatment of poplar wood by leading technologies.</style></title><secondary-title><style face="normal" font="default" size="100%">Biotechnology progress</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biotechnol. Prog.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Mar-Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">25</style></volume><pages><style face="normal" font="default" size="100%">333-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Through a Biomass Refining Consortium for Applied Fundamentals and Innovation among Auburn University, Dartmouth College, Michigan State University, the National Renewable Energy Laboratory, Purdue University, Texas A&amp;M University, the University of British Columbia, and the University of California at Riverside, leading pretreatment technologies based on ammonia fiber expansion, aqueous ammonia recycle, dilute sulfuric acid, lime, neutral pH, and sulfur dioxide were applied to a single source of poplar wood, and the remaining solids from each technology were hydrolyzed to sugars using the same enzymes. Identical analytical methods and a consistent material balance methodology were employed to develop comparative performance data for each combination of pretreatment and enzymes. Overall, compared to data with corn stover employed previously, the results showed that poplar was more recalcitrant to conversion to sugars and that sugar yields from the combined operations of pretreatment and enzymatic hydrolysis varied more among pretreatments. However, application of more severe pretreatment conditions gave good yields from sulfur dioxide and lime, and a recombinant yeast strain fermented the mixed stream of glucose and xylose sugars released by enzymatic hydrolysis of water washed solids from all pretreatments to ethanol with similarly high yields. An Agricultural and Industrial Advisory Board followed progress and helped steer the research to meet scientific and commercial needs.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19294662?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lu, Yulin</style></author><author><style face="normal" font="default" size="100%">Warner, Ryan</style></author><author><style face="normal" font="default" size="100%">Sedlak, Miroslav</style></author><author><style face="normal" font="default" size="100%">Ho, Nancy</style></author><author><style face="normal" font="default" size="100%">Mosier, Nathan S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Comparison of glucose/xylose cofermentation of poplar hydrolysates processed by different pretreatment technologies.</style></title><secondary-title><style face="normal" font="default" size="100%">Biotechnology progress</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biotechnol. Prog.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Mar-Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">25</style></volume><pages><style face="normal" font="default" size="100%">349-56</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The inhibitory effects of furfural and acetic acid on the fermentation of xylose and glucose to ethanol in YEPDX medium by a recombinant Saccharomyces cerevisiae strain (LNH-ST 424A) were investigated. Initial furfural concentrations below 5 g/L caused negligible inhibition to glucose and xylose consumption rates in batch fermentations with high inoculum (4.5-6.0 g/L). At higher initial furfural concentrations (10-15 g/L) the inhibition became significant with xylose consumption rates especially affected. Interactive inhibition between acetic acid and pH were observed and quantified, and the results suggested the importance of conditioning the pH of hydrolysates for optimal fermentation performance. Poplar biomass pretreated by various CAFI processes (dilute acid, AFEX, ARP, SO(2)-catalyzed steam explosion, and controlled-pH) under respective optimal conditions was enzymatically hydrolyzed, and the mixed sugar streams in the hydrolysates were fermented. The 5-hydroxymethyl furfural (HMF) and furfural concentrations were low in all hydrolysates and did not pose negative effects on fermentation. Maximum ethanol productivity showed that 0-6.2 g/L initial acetic acid does not substantially affect the ethanol fermentation with proper pH adjustment, confirming the results from rich media fermentations with reagent grade sugars.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19319980?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Tsuneda, Akihiko</style></author><author><style face="normal" font="default" size="100%">Wang, Wei</style></author><author><style face="normal" font="default" size="100%">Tsuneda, Ichiko</style></author><author><style face="normal" font="default" size="100%">Currah, Randolph S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Endomembrane system of aspen root cells plays a key role in defense against a common fungal root endophyte, Cryptosporiopsis radicicola.</style></title><secondary-title><style face="normal" font="default" size="100%">Mycologia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mycologia</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Mar-Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">101</style></volume><pages><style face="normal" font="default" size="100%">182-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The host-endophyte interaction between roots of aspen (Populus tremuloides) and Cryptosporiopsis radicicola was examined primarily by transmission electron microscopy. Hyphae growing on the exterior of the inoculated roots had a thick, electron-dense, adhesive sheath. At hyphal contact and penetration, host epidermal cells exhibited a series of defense responses (viz. formation of papillae and partition walls, general wall thickening and walling-off of internal hyphae). In papilla formation, loop-shaped, rough endoplasmic reticula (rER) gave rise to globose secretory vesicles that accumulated around and then fused to the developing papilla. Unlike papillae, general wall thickening was associated with the Golgi apparatus (GA) that produced cell wall materials; 1-3 layers of Golgi cisternae were in contact with or in the immediate proximity (mostly within 0-0.5 microm) of and lying parallel to the host cell wall, where they budded out numerous subglobose vesicles that fused directly to the host cell wall and made it thicker. Partition wall formation and walling-off of internal hyphae also were common; the former was associated with an extended single cisterna, which was indistinguishable from rER or individual cisternae of GA, and in the latter phenomenon internal hyphae were encased by electron-dense material containing numerous ribosomes and membranous elements that were derived apparently from proliferated rER. These pronounced defense responses protected the stele and contributed to making C. radicicola endophytic rather than pathogenic.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19397190?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Balan, Venkatesh</style></author><author><style face="normal" font="default" size="100%">Sousa, Leonardo da Costa</style></author><author><style face="normal" font="default" size="100%">Chundawat, Shishir P S</style></author><author><style face="normal" font="default" size="100%">Marshall, Derek</style></author><author><style face="normal" font="default" size="100%">Sharma, Lekh N</style></author><author><style face="normal" font="default" size="100%">Chambliss, C Kevin</style></author><author><style face="normal" font="default" size="100%">Dale, Bruce E</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Enzymatic digestibility and pretreatment degradation products of AFEX-treated hardwoods (Populus nigra).</style></title><secondary-title><style face="normal" font="default" size="100%">Biotechnology progress</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biotechnol. Prog.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Mar-Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">25</style></volume><pages><style face="normal" font="default" size="100%">365-75</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">There is a growing need to find alternatives to crude oil as the primary feed stock for the chemicals and fuel industry and ethanol has been demonstrated to be a viable alternative. Among the various feed stocks for producing ethanol, poplar (Populus nigra x Populus maximowiczii) is considered to have great potential as a biorefinery feedstock in the United States, due to their widespread availability and good productivity in several parts of the country. We have optimized AFEX pretreatment conditions (180 degrees C, 2:1 ammonia to biomass loading, 233% moisture, 30 minutes residence time) and by using various combinations of enzymes (commercical celluloses and xylanases) to achieve high glucan and xylan conversion (93 and 65%, respectively). We have also identified and quantified several important degradation products formed during AFEX using liquid chromatography followed by mass spectrometry (LC-MS/MS). As a part of degradation product analysis, we have also quantified oligosaccharides in the AFEX water wash extracts by acid hydrolysis. It is interesting to note that corn stover (C4 grass) can be pretreated effectively using mild AFEX pretreatment conditions, while on the other hand hardwood poplar requires much harsher AFEX conditions to obtain equivalent sugar yields upon enzymatic hydrolysis. Comparing corn stover and poplar, we conclude that pretreatment severity and enzymatic hydrolysis efficiency are dictated to a large extent by lignin carbohydrate complexes and arabinoxylan cross-linkages for AFEX.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19326425?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kim, Youngmi</style></author><author><style face="normal" font="default" size="100%">Mosier, Nathan S</style></author><author><style face="normal" font="default" size="100%">Ladisch, Michael R</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Enzymatic digestion of liquid hot water pretreated hybrid poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Biotechnology progress</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biotechnol. Prog.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Mar-Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">25</style></volume><pages><style face="normal" font="default" size="100%">340-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Liquid hot (LHW) water pretreatment (LHW) of lignocellulosic material enhances enzymatic conversion of cellulose to glucose by solubilizing hemicellulose fraction of the biomass, while leaving the cellulose more reactive and accessible to cellulase enzymes. Within the range of pretreatment conditions tested in this study, the optimized LHW pretreatment conditions for a 15% (wt/vol) slurry of hybrid poplar were found to be 200(o)C, 10 min, which resulted in the highest fermentable sugar yield with minimal formation of sugar decomposition products during the pretreatment. The LHW pretreatment solubilized 62% of hemicellulose as soluble oligomers. Hot-washing of the pretreated poplar slurry increased the efficiency of hydrolysis by doubling the yield of glucose for a given enzyme dose. The 15% (wt/vol) slurry of hybrid poplar, pretreated at the optimal conditions and hot-washed, resulted in 54% glucose yield by 15 FPU cellulase per gram glucan after 120 h. The hydrolysate contained 56 g/L glucose and 12 g/L xylose. The effect of cellulase loading on the enzymatic digestibility of the pretreated poplar is also reported. Total monomeric sugar yield (glucose and xylose) reached 67% after 72 h of hydrolysis when 40 FPU cellulase per gram glucan were used. An overall mass balance of the poplar-to-ethanol process was established based on the experimentally determined composition and hydrolysis efficiencies of the liquid hot water pretreated poplar.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19294734?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gupta, Rajesh</style></author><author><style face="normal" font="default" size="100%">Lee, Y Y</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Pretreatment of hybrid poplar by aqueous ammonia.</style></title><secondary-title><style face="normal" font="default" size="100%">Biotechnology progress</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biotechnol. Prog.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Mar-Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">25</style></volume><pages><style face="normal" font="default" size="100%">357-64</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Enzymatic hydrolysis of hybrid poplar treated by ammonia recycle percolation (ARP) was studied applying cellulase enzyme supplemented with additional xylanase or pectinase. The effect of xylanase addition was much more significant than pectinase addition. Conversion of ARP-treated hybrid poplar to ethanol was carried out by simultaneous saccharification and fermentation (SSF) and SS and cofermentation (SSCF). The maximum ethanol yield observed from the SSCF experiment was 78% of theoretical maximum based on the total carbohydrate (glucan + xylan). The same feedstock was also treated by soaking in aqueous ammonia (SAA), a batch pretreatment process with lower severity than ARP. The test results indicated that relatively high severity is required to attain acceptable level of digestibility of hybrid poplar. In order to lower the severity of the pretreatment, addition of H(2)O(2) was attempted in the SAA. Addition of H(2)O(2) significantly enhanced delignification of hybrid poplar due to its oxidative degradation of lignin. Several different H(2)O(2) feeding schemes and different temperature profiles were attempted in operation of the SAA to investigate the effects of H(2)O(2) on degradation of lignin and carbohydrates in hybrid poplar. More than 60% of lignin in hybrid poplar was removed with stepwise-increase of temperature (60-120 degrees C after 4h of reaction). Increase of carbohydrate degradation was also observed under this condition.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19322817?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sierra, Rocio</style></author><author><style face="normal" font="default" size="100%">Granda, Cesar</style></author><author><style face="normal" font="default" size="100%">Holtzapple, Mark T</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Short-term lime pretreatment of poplar wood.</style></title><secondary-title><style face="normal" font="default" size="100%">Biotechnology progress</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biotechnol. Prog.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Mar-Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">25</style></volume><pages><style face="normal" font="default" size="100%">323-32</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Short-term lime pretreatment uses lime and high-pressure oxygen to significantly increase the digestibility of poplar wood. When the treated poplar wood was enzymatically hydrolyzed, glucan and xylan were converted to glucose and xylose, respectively. To calculate product yields from raw biomass, these sugars were expressed as equivalent glucan and xylan. To recommend pretreatment conditions, the single criterion was the maximum overall glucan and xylan yields using a cellulase loading of 15 FPU/g glucan in raw biomass. On this basis, the recommended conditions for short-term lime pretreatment of poplar wood follow: (1) 2 h, 140 degrees C, 21.7 bar absolute and (2) 2 h, 160 degrees C, and 14.8 bar absolute. In these two cases, the reactivity was nearly identical, thus the selected condition depends on the economic trade off between pressure and temperature. Considering glucose and xylose and their oligomers produced during 72 h of enzymatic hydrolysis, the overall yields attained under these recommended conditions follow: (1) 95.5 g glucan/100 g of glucan in raw biomass and 73.1 g xylan/100 g xylan in raw biomass and (2) 94.2 g glucan/100 g glucan in raw biomass and 73.2 g xylan/100 g xylan in raw biomass. The yields improved by increasing the enzyme loading. An optimal enzyme cocktail was identified as 67% cellulase, 12% beta-glucosidase, and 24% xylanase (mass of protein basis) with cellulase activity of 15 FPU/g glucan in raw biomass and total enzyme loading of 51 mg protein/g glucan in raw biomass. Ball milling the lime-treated poplar wood allowed for 100% conversion of glucan in 120 h with a cellulase loading of only 10 FPU/g glucan in raw biomass.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19291802?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Berta, Monica</style></author><author><style face="normal" font="default" size="100%">Giovannelli, Alessio</style></author><author><style face="normal" font="default" size="100%">Potenza, Emilio</style></author><author><style face="normal" font="default" size="100%">Traversi, Maria Laura</style></author><author><style face="normal" font="default" size="100%">Racchi, Milvia Luisa</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Type 3 metallothioneins respond to water deficit in leaf and in the cambial zone of white poplar (Populus alba).</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Mar 15</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">166</style></volume><pages><style face="normal" font="default" size="100%">521-30</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The involvement of metallothioneins (MTs) in response to plant water stress and recovery was assessed by analyzing gene expression in leaves and in the cambial zone of white poplar. One-year-old plants were submitted to two different watering regimes: irrigation was withheld for 9d and then resumed until day 17, or soil moisture was maintained to field capacity by irrigation during the experiment. Changes in leaves and stem water relations, gas exchange and CO(2) assimilation were recorded. The expression profiles of MT genes were analyzed in developing leaves and the cambial zone at maximum stress levels and after recovery and compared with the watered controls. Whole-plant water relations were significantly affected by water deprivation, though a complete recovery of plant water status was reached after resumption of watering. Withholding irrigation resulted in a significant decrease of leaf turgor potential and relative water content without a significant increase of the osmotic potential at full turgor. Similarly, stem water content decreased, leading to a marked increase of stem shrinkage, confirming that mild water stress affected primarily tissue water status. Following water depletion, the transcript analysis of MT genes revealed increased expression of type 3a and 3b MT genes in cambial tissues, and particularly in leaves. After water resumption, transcription decreased, suggesting that the changes in gene expression were related to water deficit. The results indicate that in leaves and, for the first time, in the cambial zone, type 3 MTs respond in a specific manner to changes in water status. These results are consistent with the regulatory cis-elements present in the 5' flanking region of type 3 MT genes.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18845361?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Mingozzi, Marco</style></author><author><style face="normal" font="default" size="100%">Montello, Paul</style></author><author><style face="normal" font="default" size="100%">Merkle, Scott</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Adventitious shoot regeneration from leaf explants of eastern cottonwood (Populus deltoides) cultured under photoautotrophic conditions.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">333-43</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Effects of photoautotrophic and photomixotrophic growth conditions on adventitious shoot regeneration from leaf explants of eastern cottonwood (Populus deltoides Bartr. ex Marsh.) were investigated. Rooting and proliferating shoot cultures (Stage I) were grown in either an elevated (1500 ppm) CO(2) concentration ([CO(2)]) at high photosynthetic photon flux (PPF; ~ 150 micromol m(-2) s(-1)) (photoautotrophic condition) with 0, 10 or 30 g l(-1) sucrose or under standard conditions (ambient (360 ppm) [CO(2)] at low PPF (~ 60 micromol m(-2) s(-1)) with 30 g l(-1) sucrose). Leaves harvested from these cultures were analyzed for soluble sugars and were used as explants for adventitious shoot regeneration (Stage II), which was also carried out under photoautotrophic and standard conditions. Photoautotrophic conditions during Stage I promoted growth of rooting shoots but inhibited axillary shoot proliferation. Photoautotrophic conditions during Stage II suppressed callus and adventitious bud production from leaf explants compared with standard conditions. The regeneration environment appeared to be more important in controlling bud formation than the conditions under which the donor shoots were grown. Regardless of Stage I treatment, bud production was up to 100-fold higher for leaves cultured under standard conditions than under photoautotrophic conditions. Once adventitious buds were differentiated from the leaf tissues, however, their elongation was faster under photoautotrophic conditions than that under standard conditions, with some shoots reaching 10 mm in length on leaf explants cultured under photoautotrophic conditions. Because total leaf soluble sugar concentration was always lowest in shoots under standard conditions, which also yielded the highest bud production, the results suggest that endogenous starvation enhanced shoot production.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19203957?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Chibani, Kamel</style></author><author><style face="normal" font="default" size="100%">Wingsle, Gunnar</style></author><author><style face="normal" font="default" size="100%">Jacquot, Jean-Pierre</style></author><author><style face="normal" font="default" size="100%">Gelhaye, Eric</style></author><author><style face="normal" font="default" size="100%">Rouhier, Nicolas</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Comparative genomic study of the thioredoxin family in photosynthetic organisms with emphasis on Populus trichocarpa.</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular plant</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol Plant</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">2</style></volume><pages><style face="normal" font="default" size="100%">308-22</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The recent genome sequencing of Populus trichocarpa and Vitis vinifera, two models of woody plants, of Sorghum bicolor, a model of monocot using C4 metabolism, and of the moss Physcomitrella patens, together with the availability of photosynthetic organism genomes allows performance of a comparative genomic study with organisms having different ways of life, reproduction modes, biological traits, and physiologies. Thioredoxins (Trxs) are small ubiquitous proteins involved in the reduction of disulfide bridges in a variety of target enzymes present in all sub-cellular compartments and involved in many biochemical reactions. The genes coding for these enzymes have been identified in these newly sequenced genomes and annotated. The gene content, organization and distribution were compared to other photosynthetic organisms, leading to a refined classification. This analysis revealed that higher plants and bryophytes have a more complex family compared to algae and cyanobacteria and to non-photosynthetic organisms, since poplar exhibits 49 genes coding for typical and atypical thioredoxins and thioredoxin reductases, namely one-third more than monocots such as Oryza sativa and S. bicolor. The higher number of Trxs in poplar is partially explained by gene duplication in the Trx m, h, and nucleoredoxin classes. Particular attention was paid to poplar genes with emphasis on Trx-like classes called Clot, thioredoxin-like, thioredoxins of the lilium type and nucleoredoxins, which were not described in depth in previous genomic studies.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19825616?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hassinen, Viivi</style></author><author><style face="normal" font="default" size="100%">Vallinkoski, Veli-Matti</style></author><author><style face="normal" font="default" size="100%">Issakainen, Sari</style></author><author><style face="normal" font="default" size="100%">Tervahauta, Arja</style></author><author><style face="normal" font="default" size="100%">Kärenlampi, Sirpa</style></author><author><style face="normal" font="default" size="100%">Servomaa, Kristina</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Correlation of foliar MT2b expression with Cd and Zn concentrations in hybrid aspen (Populus tremulaxtremuloides) grown in contaminated soil.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">157</style></volume><pages><style face="normal" font="default" size="100%">922-30</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Metal uptake and its effect on foliar metallothionein 2b (MT2b) mRNA levels were studied in hybrid aspen (Populus tremulaxtremuloides) in field conditions. The trees were planted on a site contaminated with several metals, including cadmium (mean 5.1 mgkg(-1)), chromium (80 mgkg(-1)), copper (180 mgkg(-1)), nickel (81 mgkg(-1)), vanadium (240 mgkg(-1)) and zinc (520 mgkg(-1)). Of the ten trace elements analyzed, only Cd and Zn accumulated in the leaves with maximal foliar concentrations of 35 and 2400 mgkg(-1) (dry weight), respectively. There was a strong correlation between Cd and Zn concentrations and bioaccumulation factors (concentration in plant/soil) in the leaves, branches and roots, suggesting similar transport mechanisms for these two metals. The levels of MT2b correlated with Cd and Zn concentrations in the leaves, demonstrating that increased MT2b expression is one of the responses of hybrid aspen to chronic metal exposure.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19062143?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Dettmer, Jan</style></author><author><style face="normal" font="default" size="100%">Elo, Annakaisa</style></author><author><style face="normal" font="default" size="100%">Helariutta, Ykä</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Hormone interactions during vascular development.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Mol. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">69</style></volume><pages><style face="normal" font="default" size="100%">347-60</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Vascular tissue in plants is unique due to its diverse and dynamic cellular patterns. Signals controlling vascular development have only recently started to emerge through biochemical, genetic, and genomic approaches in several organisms, such as Arabidopsis, Populus, and Zinnia. These signals include hormones (auxin, brassinosteroids, and cytokinins, in particular), other small regulatory molecules, their transporters, receptors, and various transcriptional regulators. In recent years it has become apparent that plant growth regulators rarely act alone, but rather their signaling pathways are interlocked in complex networks; for example, polar auxin transport (PAT) regulates vascular development during various stages and an emerging theme is its modulation by other growth regulators, depending on the developmental context. Also, several synergistic or antagonistic interactions between various growth regulators have been described. Furthermore, shoot-root interactions appear to be important for this signal integration.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18654740?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Vamerali, Teofilo</style></author><author><style face="normal" font="default" size="100%">Bandiera, Marianna</style></author><author><style face="normal" font="default" size="100%">Coletto, Lucia</style></author><author><style face="normal" font="default" size="100%">Zanetti, Federica</style></author><author><style face="normal" font="default" size="100%">Dickinson, Nicholas M</style></author><author><style face="normal" font="default" size="100%">Mosca, Giuliano</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Phytoremediation trials on metal- and arsenic-contaminated pyrite wastes (Torviscosa, Italy).</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">157</style></volume><pages><style face="normal" font="default" size="100%">887-94</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">At a site in Udine, Italy, a 0.7m layer of As, Co, Cu, Pb and Zn contaminated wastes derived from mineral roasting for sulphur extraction had been covered with an unpolluted 0.15m layer of gravelly soil. This study investigates whether woody biomass phytoremediation is a realistic management option. Comparing ploughing and subsoiling (0.35m depth), the growth of Populus and Salix and trace element uptake were investigated in both pot and field trials. Species differences were marginal and species selection was not critical. Impaired above-ground productivity and low translocation of trace elements showed that bioavailable contaminant stripping was not feasible. The most significant finding was of coarse and fine roots proliferation in surface layers that provided a significant sink for trace elements. We conclude that phytostabilisation and effective immobilisation of metals and As could be achieved at the site by soil amelioration combined with woody species establishment. Confidence to achieve a long-term and sustainable remediation requires a more complete quantification of root dynamics and a better understanding of rhizosphere processes.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19073356?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rasulov, Bahtijor</style></author><author><style face="normal" font="default" size="100%">Copolovici, Lucian</style></author><author><style face="normal" font="default" size="100%">Laisk, Agu</style></author><author><style face="normal" font="default" size="100%">Niinemets, Ulo</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Postillumination isoprene emission: in vivo measurements of dimethylallyldiphosphate pool size and isoprene synthase kinetics in aspen leaves.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">149</style></volume><pages><style face="normal" font="default" size="100%">1609-18</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The control of foliar isoprene emission is shared between the activity of isoprene synthase, the terminal enzyme catalyzing isoprene formation from dimethylallyldiphosphate (DMADP), and the pool size of DMADP. Due to limited in vivo information of isoprene synthase kinetic characteristics and DMADP pool sizes, the relative importance of these controls is under debate. In this study, the phenomenon of postillumination isoprene release was employed to develop an in vivo method for estimation of the DMADP pool size and to determine isoprene synthase kinetic characteristics in hybrid aspen (Populus tremula x Populus tremuloides) leaves. The method is based on observations that after switching off the light, isoprene emission continues for 250 to 300 s and that the integral of the postillumination isoprene emission is strongly correlated with the isoprene emission rate before leaf darkening, thus quantitatively estimating the DMADP pool size associated with leaf isoprene emission. In vitro estimates demonstrated that overall leaf DMADP pool was very large, almost an order of magnitude larger than the in vivo pool. Yet, the difference between total DMADP pools in light and in darkness (light-dependent DMADP pool) was tightly correlated with the in vivo estimates of the DMADP pool size that is responsible for isoprene emission. Variation in in vivo DMADP pool size was obtained by varying light intensity and atmospheric CO(2) and O(2) concentrations. From these experiments, the in vivo kinetic constants of isoprene synthase were determined. In vivo isoprene synthase kinetic characteristics suggested that isoprene synthase mainly operates under substrate limitation and that short-term light, CO(2), and O(2) dependencies of isoprene emission result from variation in DMADP pool size rather than from modifications in isoprene synthase activity.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19129417?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wu, Libin</style></author><author><style face="normal" font="default" size="100%">Guo, Shipeng</style></author><author><style face="normal" font="default" size="100%">Wang, Chao</style></author><author><style face="normal" font="default" size="100%">Yang, Zhengyu</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Production of alkanes (C(7)-C(29)) from different part of poplar tree via direct deoxy-liquefaction.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioresource technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bioresour. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">100</style></volume><pages><style face="normal" font="default" size="100%">2069-76</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Poplar leaves, poplar bark and poplar wood were deoxy-liquefied directly in an air-proof stainless steel reactor at different temperatures. The oils from leaves at 350 degrees C, from bark at 400 degrees C and from wood at 450 degrees C, at which the liquid product yields were the maximum, were analyzed by GC-MS. The oils obtained from three parts of poplar tree were quite different from each other in the relative contents of their compositions. The oil from leaves was rich in hydrocarbons (alkanes: C(7)-C(29); aromatics) and poor in phenolics, while oil from wood was rich in phenolics and poor in hydrocarbons. The oil from bark was moderate. Relative contents of hydrocarbons in the leaves oil were as high as 60.01% but decreased to 29.71% in bark oil and 11.43% in wood oil. GC analysis of gases and FT-IR, GC-MS and elemental analysis of oils were performed in this study.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19028091?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Cinege, Gyöngyi</style></author><author><style face="normal" font="default" size="100%">Louis, Sandrine</style></author><author><style face="normal" font="default" size="100%">Hänsch, Robert</style></author><author><style face="normal" font="default" size="100%">Schnitzler, Jörg-Peter</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Regulation of isoprene synthase promoter by environmental and internal factors.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Mol. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">69</style></volume><pages><style face="normal" font="default" size="100%">593-604</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Isoprene synthase (ISPS) catalyzes the formation of isoprene, an important volatile terpenoid with strong effects on global atmospheric chemistry and protective physiological functions in plant leaves. Many terpene synthase genes including isoprene synthase, a member of the TPS-b cluster of this numerous gene family, were already functionally analysed but much less is known about regulation of their promoters. To study regulation of the PcISPS gene in detail we developed transgenic Grey poplar (Populus x canescens) and Arabidopsis thaliana plants in which the PcISPS promoter is fused to enhanced green fluorescent protein (E-GFP) and beta-glucuronidase (GUS) reporter genes. We analysed these reporters during plant development, for organ specificity and in plants subjected to different light and temperature regimes. We observed low promoter activity in non-isoprene emitting tissue like roots where ISPS gene is transcribed but no active enzyme is detectable. In leaves we demonstrate that light and temperature directly modulate ISPS promoter activity. Moreover, with confocal laser scanning microscopy we show a cell specific gradient of ISPS promoter activity within the leaf parenchyma depending on light direction. Our results indicate that ISPS promoter activity, which correlates with basal isoprene emission capacity, is not uniformly distributed within leaf tissue and that it can adapt rapidly towards internal as well as external environmental stimuli.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19067180?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Naik, Dhiraj</style></author><author><style face="normal" font="default" size="100%">Smith, Ernest</style></author><author><style face="normal" font="default" size="100%">Cumming, Jonathan R</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Rhizosphere carbon deposition, oxidative stress and nutritional changes in two poplar species exposed to aluminum.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">423-36</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Species and hybrids in the genus Populus have become the focus of investigation for use in biofuels production and their capacity to sequester carbon (C) in the environment. The identification of species resistant to marginal edaphic sites may be important in both of these endeavors. Plant growth, total dissolved organic carbon (TOC) and low molecular weight organic acid (OA) production, antioxidative enzyme activities and mineral content were assessed in Populus tremuloides L. and Populus trichocarpa Torr. &amp; Gray seedlings under exposure to aluminum (Al). Both species were sensitive to Al, with significant reductions in shoot and root biomass at and above 50 microM Al. Exposure to Al induced 40-fold increases in TOC deposition in P. tremuloides and 100-fold increases in P. trichocarpa. In P. tremuloides, Al treatment induced root exudation of malic and citric acids, while Al increased exudation of citrate and oxalate in P. trichocarpa. Organic acids accounted for 20-64% of total C released upon Al exposure, with the proportion of OAs increasing in P. tremuloides and decreasing in P. trichocarpa. Dose-dependent responses of catalase and ascorbate peroxidase were observed in both root and leaf tissues, indicating that Al exposure induced oxidative stress in poplar. Treatment at and above 100 microM Al reduced the concentrations of calcium (Ca) and magnesium (Mg) in roots and leaves, whereas Al at or above 50 microM reduced root and leaf phosphorous (P) concentrations. The majority of Al taken up was retained in the root system. Even with the induction of OA exudation and accumulation, P. tremuloides and P. trichocarpa remained sensitive to Al, as evidenced by elevated antioxidative enzyme activities, which may reflect inhibition of Ca or P uptake and destabilization of cell homeostasis in these poplar species. Although plants exhibited reductions in growth and evidence of oxidative and nutritional stress, total C rhizodeposition rates for both species increased with increasing Al exposure concentration. Estimated C deposition rates of 16 mg C plant(-1) day(-1) were four-times larger than previously reported values for forest tree species, indicating that edaphic stress plays an important role in C flux to the rhizosphere.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19203961?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Feau, Nicolas</style></author><author><style face="normal" font="default" size="100%">Vialle, Agathe</style></author><author><style face="normal" font="default" size="100%">Allaire, Mathieu</style></author><author><style face="normal" font="default" size="100%">Tanguay, Philippe</style></author><author><style face="normal" font="default" size="100%">Joly, David L</style></author><author><style face="normal" font="default" size="100%">Frey, Pascal</style></author><author><style face="normal" font="default" size="100%">Callan, Brenda E</style></author><author><style face="normal" font="default" size="100%">Hamelin, Richard C</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Fungal pathogen (mis-) identifications: a case study with DNA barcodes on Melampsora rusts of aspen and white poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Mycological research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mycol. Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun-Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">113</style></volume><pages><style face="normal" font="default" size="100%">713-24</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Wide variation and overlap in morphological characters have led to confusion in species identification within the fungal rust genus Melampsora. The Melampsora species with uredinial-telial stages on white poplar and aspens are especially prone to misidentification. This group includes the Melampsora populnea species complex and the highly destructive pine twisting rust, Melampsora pinitorqua, which alternates between hosts in Populus section Populus and Pinus. Our objective was to compare morphologically based identification to genetic material extracted from Melampsora species pathogenic to aspen and white poplar. We compared morphometric traits and DNA barcodes obtained from internal transcribed spacer (ITS), large ribosomal RNA subunit (28S), and mitochondrial cytochrome oxidase 1 (CO1) sequences to delimit within this taxonomically difficult group. Eight different Melampsora species were initially defined based on host specificity and morphometric data. DNA barcodes were then overlaid on these initial species definitions. The DNA barcodes, specifically those defined on ITS and 28S sequences, provided a highly accurate means of identifying and resolving Melampsora taxa. We highlighted species misidentification in specimens from Canadian herbaria related to either Melampsora medusae f. sp. tremuloidae or Melampsora aecidioides. Finally, we evidenced that the north-American species found on Populus alba, M. aecidioides is closely related but distinct from the four species of the M. populnea complex (Melampsora larici-tremulae, Melampsora magnusiana, Melampsora pinitorqua, and Melampsora rostrupii) found in Eurasia.</style></abstract><issue><style face="normal" font="default" size="100%">Pt 6-7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19249365?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lu, Fake</style></author><author><style face="normal" font="default" size="100%">Zheng, Wei</style></author><author><style face="normal" font="default" size="100%">Huang, Zhiwei</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Coherent anti-Stokes Raman scattering microscopy using tightly focused radially polarized light.</style></title><secondary-title><style face="normal" font="default" size="100%">Optics letters</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Opt Lett</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun 15</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">34</style></volume><pages><style face="normal" font="default" size="100%">1870-2</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We report a radially polarized coherent anti-Stokes Raman scattering (RP-CARS) microscopy for facilitating longitudinally oriented molecules detection. We observe that under tight focusing of radially polarized pump and Stokes light fields with a high-NA objective, RP-CARS radiation from molecules oriented along the longitudinal direction is approximately threefold stronger than that using linearly polarized CARS (LP-CARS) technique. The lateral resolution of RP-CARS imaging can be improved by about 10% compared to the LP-CARS imaging. We demonstrate this RP-CARS technique by imaging the sectioned cottonwood leaf vascular bundles.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19529731?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Post, David M</style></author><author><style face="normal" font="default" size="100%">Palkovacs, Eric P</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Eco-evolutionary feedbacks in community and ecosystem ecology: interactions between the ecological theatre and the evolutionary play.</style></title><secondary-title><style face="normal" font="default" size="100%">Philosophical transactions of the Royal Society of London. Series B, Biological sciences</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Philos. Trans. R. Soc. Lond., B, Biol. Sci.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun 12</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">364</style></volume><pages><style face="normal" font="default" size="100%">1629-40</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Interactions between natural selection and environmental change are well recognized and sit at the core of ecology and evolutionary biology. Reciprocal interactions between ecology and evolution, eco-evolutionary feedbacks, are less well studied, even though they may be critical for understanding the evolution of biological diversity, the structure of communities and the function of ecosystems. Eco-evolutionary feedbacks require that populations alter their environment (niche construction) and that those changes in the environment feed back to influence the subsequent evolution of the population. There is strong evidence that organisms influence their environment through predation, nutrient excretion and habitat modification, and that populations evolve in response to changes in their environment at time-scales congruent with ecological change (contemporary evolution). Here, we outline how the niche construction and contemporary evolution interact to alter the direction of evolution and the structure and function of communities and ecosystems. We then present five empirical systems that highlight important characteristics of eco-evolutionary feedbacks: rotifer-algae chemostats; alewife-zooplankton interactions in lakes; guppy life-history evolution and nutrient cycling in streams; avian seed predators and plants; and tree leaf chemistry and soil processes. The alewife-zooplankton system provides the most complete evidence for eco-evolutionary feedbacks, but other systems highlight the potential for eco-evolutionary feedbacks in a wide variety of natural systems.</style></abstract><issue><style face="normal" font="default" size="100%">1523</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19414476?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Mauriat, Mélanie</style></author><author><style face="normal" font="default" size="100%">Moritz, Thomas</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Analyses of GA20ox- and GID1-over-expressing aspen suggest that gibberellins play two distinct roles in wood formation.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">58</style></volume><pages><style face="normal" font="default" size="100%">989-1003</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Gibberellins (GAs) are involved in many aspects of plant development, including shoot growth, flowering and wood formation. Increased levels of bioactive GAs are known to induce xylogenesis and xylem fiber elongation in aspen. However, there is currently little information on the response pathway(s) that mediate GA effects on wood formation. Here we characterize an important element of the GA pathway in hybrid aspen: the GA receptor, GID1. Four orthologs of GID1 were identified in Populus tremula x P. tremuloides (PttGID1.1-1.4). These were functional when expressed in Arabidopsis thaliana, and appear to present a degree of sub-functionalization in hybrid aspen. PttGID1.1 and PttGID1.3 were over-expressed in independent lines of hybrid aspen using either the 35S promoter or a xylem-specific promoter (LMX5). The 35S:PttGID1 over-expressors shared several phenotypic traits previously described in 35S:AtGA20ox1 over-expressors, including rapid growth, increased elongation, and increased xylogenesis. However, their xylem fibers were not elongated, unlike those of 35S:AtGA20ox1 plants. Similar differences in the xylem fiber phenotype were observed when PttGID1.1, PttGID1.3 or AtGA20ox1 were expressed under the control of the LMX5 promoter, suggesting either that PttGID1.1 and PttGID1.3 play no role in fiber elongation or that GA homeostasis is strongly controlled when GA signaling is altered. Our data suggest that GAs are required in two distinct wood-formation processes that have tissue-specific signaling pathways: xylogenesis, as mediated by GA signaling in the cambium, and fiber elongation in the developing xylem.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19228336?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ramírez-Carvajal, Gustavo A</style></author><author><style face="normal" font="default" size="100%">Morse, Alison M</style></author><author><style face="normal" font="default" size="100%">Dervinis, Christopher</style></author><author><style face="normal" font="default" size="100%">Davis, John M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The cytokinin type-B response regulator PtRR13 is a negative regulator of adventitious root development in Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">150</style></volume><pages><style face="normal" font="default" size="100%">759-71</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Adventitious root formation at the base of plant cuttings is an innate de novo organogenesis process that allows massive vegetative propagation of many economically and ecologically important species. The early molecular events following shoot excision are not well understood. Using whole-genome microarrays, we detected significant transcriptome remodeling during 48 h following shoot removal in Populus tremula x Populus alba softwood cuttings in the absence of exogenous auxin, with 27% and 36% of the gene models showing differential abundance between 0 and 6 h and between 6 and 24 h, respectively. During these two time intervals, gene networks involved in protein turnover, protein phosphorylation, molecular transport, and translation were among the most significantly regulated. Transgenic lines expressing a constitutively active form of the Populus type-B cytokinin response regulator PtRR13 (DeltaDDKPtRR13) have a delayed rooting phenotype and cause misregulation of CONTINUOUS VASCULAR RING1, a negative regulator of vascularization; PLEIOTROPIC DRUG RESISTANCE TRANSPORTER9, an auxin efflux transporter; and two APETALA2/ETHYLENE RESPONSE FACTOR genes with sequence similarity to TINY. Inappropriate cytokinin action via DeltaDDKPtRR13 expression appeared to disrupt adventitious root development 24 h after shoot excision, when root founder cells are hypothesized to be sensitive to the negative effects of cytokinin. Our results are consistent with PtRR13 acting downstream of cytokinin to repress adventitious root formation in intact plants, and that reduced cytokinin signaling after shoot excision enables coordinated expression of ethylene, auxin, and vascularization pathways leading to adventitious root development.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19395410?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ramírez, Claudio C</style></author><author><style face="normal" font="default" size="100%">Guerra, Fernando P</style></author><author><style face="normal" font="default" size="100%">Zuñiga, Rafael E</style></author><author><style face="normal" font="default" size="100%">Cordero, Cecilia</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Differential expression of candidate defense genes of poplars in response to aphid feeding.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of economic entomology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Econ. Entomol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">102</style></volume><pages><style face="normal" font="default" size="100%">1070-4</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Species belonging to the genus Populus (poplars) produce a series of defensive proteins in response to insect damage. Proteinase inhibitors, polyphenol oxidases, and chitinases are the most relevant and intensively studied proteins. Most of the knowledge about the relation between these proteins and herbivores has been obtained from studies with chewing insects. Nothing is known about whether phloem-feeder insects such as aphids are able to trigger a comparable response. In the current study, the expression of genes encoding a Kunitz trypsin inhibitor 3 (KTI3), a polyphenol oxidase 1 (PPO1), and a class I chitinase (CHI) was characterized in two poplar hybrids (one resistant hybrid and one susceptible hybrid, to aphids) attacked by the aphid Chaitophorus leucomelas Koch. The expression pattern was analyzed using a semiquantitative reverse transcription-polymerase chain reaction approach. The expression of KTI3 was increased by aphids only in the aphid-susceptible hybrid. Differently, PPO1 expression was increased by aphids in the aphid-resistant hybrid. The expression of CHI was down-regulated by aphids in the susceptible hybrid. This is the first study to report the differential expression of poplar defense genes in response to phloem-feeder insects such as aphids. The findings from the current study suggest that the expression levels of defensive proteins are affected by poplar genotype and by aphid infestation.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19610421?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lee, Chanhui</style></author><author><style face="normal" font="default" size="100%">Teng, Quincy</style></author><author><style face="normal" font="default" size="100%">Huang, Wenlin</style></author><author><style face="normal" font="default" size="100%">Zhong, Ruiqin</style></author><author><style face="normal" font="default" size="100%">Ye, Zheng-Hua</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Down-regulation of PoGT47C expression in poplar results in a reduced glucuronoxylan content and an increased wood digestibility by cellulase.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant &amp; cell physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">50</style></volume><pages><style face="normal" font="default" size="100%">1075-89</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Xylan is the second most abundant polysaccharide in dicot wood. Unraveling the biosynthetic pathway of xylan is important not only for our understanding of the process of wood formation but also for our rational engineering of wood for biofuel production. Although several glycosyltransferases are implicated in glucuronoxylan (GX) biosynthesis in Arabidopsis, whether their close orthologs in woody tree species are essential for GX biosynthesis during wood formation has not been investigated. In fact, no studies have been reported to evaluate the effects of alterations in secondary wall-associated glycosyltransferases on wood formation in tree species. In this report, we demonstrate that PoGT47C, a poplar glycosyltransferase belonging to family GT47, is essential for the normal biosynthesis of GX and the normal secondary wall thickening in the wood of the hybrid poplar Populus alba x tremula. RNA interference (RNAi) inhibition of PoGT47C resulted in a drastic reduction in the thickness of secondary walls, a deformation of vessels and a decreased amount of GX in poplar wood. Structural analysis of GX using nuclear magnetic resonance (NMR) spectroscopy demonstrated that the reducing end of GX from poplar wood contains the tetrasaccharide sequence, beta-d-Xylp-(1--&gt;3)-alpha-l-Rhap-(1--&gt;2)-alpha-d-GalpA-(1--&gt;4)-d-Xylp, and that its abundance was significantly decreased in the GX from the wood of the GT47C-RNAi lines. The transgenic wood was found to yield more glucose by cellulase digestion than the wild-type wood, indicating that the GX reduction in wood reduces the recalcitrance of wood to cellulase digestion. Together, these results provide direct evidence demonstrating that the PoGT47C glycosyltransferase is essential for normal GX biosynthesis in poplar wood and that GX modification could improve the digestibility of wood cellulose by cellulase.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19395414?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Stewart, Jaclyn J</style></author><author><style face="normal" font="default" size="100%">Akiyama, Takuya</style></author><author><style face="normal" font="default" size="100%">Chapple, Clint</style></author><author><style face="normal" font="default" size="100%">Ralph, John</style></author><author><style face="normal" font="default" size="100%">Mansfield, Shawn D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The effects on lignin structure of overexpression of ferulate 5-hydroxylase in hybrid poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">150</style></volume><pages><style face="normal" font="default" size="100%">621-35</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Poplar (Populus tremula x alba) lignins with exceedingly high syringyl monomer levels are produced by overexpression of the ferulate 5-hydroxylase (F5H) gene driven by a cinnamate 4-hydroxylase (C4H) promoter. Compositional data derived from both standard degradative methods and NMR analyses of the entire lignin component (as well as isolated lignin fraction) indicated that the C4HF5H transgenic's lignin was comprised of as much as 97.5% syringyl units (derived from sinapyl alcohol), the remainder being guaiacyl units (derived from coniferyl alcohol); the syringyl level in the wild-type control was 68%. The resultant transgenic lignins are more linear and display a lower degree of polymerization. Although the crucial beta-ether content is similar, the distribution of other interunit linkages in the lignin polymer is markedly different, with higher resinol (beta-beta) and spirodienone (beta-1) contents, but with virtually no phenylcoumarans (beta-5, which can only be formed from guaiacyl units). p-Hydroxybenzoates, acylating the gamma-positions of lignin side chains, were reduced by &gt;50%, suggesting consequent impacts on related pathways. A model depicting the putative structure of the transgenic lignin resulting from the overexpression of F5H is presented. The altered structural features in the transgenic lignin polymer, as revealed here, support the contention that there are significant opportunities to improve biomass utilization by exploiting the malleability of plant lignification processes.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19386808?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Custers, René</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">First GM trial in Belgium since 2002.</style></title><secondary-title><style face="normal" font="default" size="100%">Nature biotechnology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Nat. Biotechnol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">27</style></volume><pages><style face="normal" font="default" size="100%">506</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19513047?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zheng, Chunfang</style></author><author><style face="normal" font="default" size="100%">Kerr Wall, P</style></author><author><style face="normal" font="default" size="100%">Leebens-Mack, James</style></author><author><style face="normal" font="default" size="100%">dePamphilis, Claude</style></author><author><style face="normal" font="default" size="100%">Albert, Victor A</style></author><author><style face="normal" font="default" size="100%">Sankoff, David</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Gene loss under neighborhood selection following whole genome duplication and the reconstruction of the ancestral Populus genome.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of bioinformatics and computational biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J Bioinform Comput Biol</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">7</style></volume><pages><style face="normal" font="default" size="100%">499-520</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We develop criteria to detect neighborhood selection effects on gene loss following whole genome duplication, and apply them to the recently sequenced poplar (Populus trichocarpa) genome. We improve on guided genome halving algorithms so that several thousand gene sets, each containing two paralogs in the descendant T of the doubling event and their single ortholog from an undoubled reference genome R, can be analyzed to reconstruct the ancestor A of T at the time of doubling. At the same time, large numbers of defective gene sets, either missing one paralog from T or missing their ortholog in R, may be incorporated into the analysis in a consistent way. We apply this genomic rearrangement distance-based approach to the poplar and grapevine (Vitis vinifera) genomes, as T and R respectively. We conclude that, after chromosome doubling, the &quot;choice&quot; of which paralogous gene pairs will lose copies is random, but that the retention of strings of single-copy genes on one chromosome versus the other is decidedly non-random.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19507287?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Takahashi, Junko</style></author><author><style face="normal" font="default" size="100%">Rudsander, Ulla J</style></author><author><style face="normal" font="default" size="100%">Hedenström, Mattias</style></author><author><style face="normal" font="default" size="100%">Banasiak, Alicja</style></author><author><style face="normal" font="default" size="100%">Harholt, Jesper</style></author><author><style face="normal" font="default" size="100%">Amelot, Nicolas</style></author><author><style face="normal" font="default" size="100%">Immerzeel, Peter</style></author><author><style face="normal" font="default" size="100%">Ryden, Peter</style></author><author><style face="normal" font="default" size="100%">Endo, Satoshi</style></author><author><style face="normal" font="default" size="100%">Ibatullin, Farid M</style></author><author><style face="normal" font="default" size="100%">Brumer, Harry</style></author><author><style face="normal" font="default" size="100%">del Campillo, Elena</style></author><author><style face="normal" font="default" size="100%">Master, Emma R</style></author><author><style face="normal" font="default" size="100%">Scheller, Henrik Vibe</style></author><author><style face="normal" font="default" size="100%">Sundberg, Björn</style></author><author><style face="normal" font="default" size="100%">Teeri, Tuula T</style></author><author><style face="normal" font="default" size="100%">Mellerowicz, Ewa J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">KORRIGAN1 and its aspen homolog PttCel9A1 decrease cellulose crystallinity in Arabidopsis stems.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant &amp; cell physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">50</style></volume><pages><style face="normal" font="default" size="100%">1099-115</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">KORRIGAN1 (KOR1) is a membrane-bound cellulase implicated in cellulose biosynthesis. PttCel9A1 from hybrid aspen (Populus tremula L. x tremuloides Michx.) has high sequence similarity to KOR1 and we demonstrate here that it complements kor1-1 mutants, indicating that it is a KOR1 ortholog. We investigated the function of PttCel9A1/KOR1 in Arabidopsis secondary growth using transgenic lines expressing 35S::PttCel9A1 and the KOR1 mutant line irx2-2. The presence of elevated levels of PttCel9A1/KOR1 in secondary walls of 35S::PttCel9A1 lines was confirmed by in muro visualization of cellulase activity. Compared with the wild type, 35S::PttCel9A1 lines had higher trifluoroacetic acid (TFA)-hydrolyzable glucan contents, similar Updegraff cellulose contents and lower cellulose crystallinity indices, as determined by (13)C solid-state nuclear magnetic resonance (NMR) spectroscopy. irx2-2 mutants had wild-type TFA-hydrolyzable glucan contents, but reduced Updegraff cellulose contents and higher than wild-type cellulose crystallinity indices. The data support the hypothesis that PttCel9A1/KOR1 activity is present in cell walls, where it facilitates cellulose biosynthesis in a way that increases the amount of non-crystalline cellulose.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19398462?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Colasurdo, Nadia</style></author><author><style face="normal" font="default" size="100%">Gélinas, Yves</style></author><author><style face="normal" font="default" size="100%">Despland, Emma</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Larval nutrition affects life history traits in a capital breeding moth.</style></title><secondary-title><style face="normal" font="default" size="100%">The Journal of experimental biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Exp. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">212</style></volume><pages><style face="normal" font="default" size="100%">1794-800</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Fitness depends not only on resource uptake but also on the allocation of these resources to various life history functions. This study explores the life-history consequences of larval diet in terms not only of larval performance but also of adult body composition and reproductive traits in the forest tent caterpillar (Malacosoma disstria Hübner). Caterpillars were reared on their preferred tree host, trembling aspen (Populus tremuloides), or on one of three artificial foods: high protein:low carbohydrate, equal protein-to-carbohydrate ratio or low protein:high carbohydrate. Survivorship, larval development rate and adult body size were lowest on the carbohydrate-biased diet and similar on the protein-biased and equal-ratio diets. Fecundity increased with body size but did not otherwise differ between diets. Moths reared on the carbohydrate-biased diet allocated a lower proportion of their mass to the ovaries and more to somatic growth whereas those on equal-ratio and protein-biased diets allocated more to reproductive tissue and less to somatic tissue. These differences in allocation to reproduction arose from differences in the size of eggs, an index of offspring quality. No differences were found in lipid and protein content of female ovaries, accessory glands or somatic tissue, or of the whole body of male moths. The findings show that physiological processes regulate the composition of the different components of the adult body. Diet effects occur as differences in overall body size and in relative allocation to these components. Although lepidopterans can, to a large extent, compensate post-ingestively for nutritionally deficient diets, investment in reproduction vs somatic growth depends on the nutrients available.</style></abstract><issue><style face="normal" font="default" size="100%">Pt 12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19482996?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Drost, Derek R</style></author><author><style face="normal" font="default" size="100%">Novaes, Evandro</style></author><author><style face="normal" font="default" size="100%">Boaventura-Novaes, Carolina</style></author><author><style face="normal" font="default" size="100%">Benedict, Catherine I</style></author><author><style face="normal" font="default" size="100%">Brown, Ryan S</style></author><author><style face="normal" font="default" size="100%">Yin, Tongming</style></author><author><style face="normal" font="default" size="100%">Tuskan, Gerald A</style></author><author><style face="normal" font="default" size="100%">Kirst, Matias</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A microarray-based genotyping and genetic mapping approach for highly heterozygous outcrossing species enables localization of a large fraction of the unassembled Populus trichocarpa genome sequence.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">58</style></volume><pages><style face="normal" font="default" size="100%">1054-67</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Microarrays have demonstrated significant power for genome-wide analyses of gene expression, and recently have also revolutionized the genetic analysis of segregating populations by genotyping thousands of loci in a single assay. Although microarray-based genotyping approaches have been successfully applied in yeast and several inbred plant species, their power has not been proven in an outcrossing species with extensive genetic diversity. Here we have developed methods for high-throughput microarray-based genotyping in such species using a pseudo-backcross progeny of 154 individuals of Populus trichocarpa and P. deltoides analyzed with long-oligonucleotide in situ-synthesized microarray probes. Our analysis resulted in high-confidence genotypes for 719 single-feature polymorphism (SFP) and 1014 gene expression marker (GEM) candidates. Using these genotypes and an established microsatellite (SSR) framework map, we produced a high-density genetic map comprising over 600 SFPs, GEMs and SSRs. The abundance of gene-based markers allowed us to localize over 35 million base pairs of previously unplaced whole-genome shotgun (WGS) scaffold sequence to putative locations in the genome of P. trichocarpa. A high proportion of sampled scaffolds could be verified for their placement with independently mapped SSRs, demonstrating the previously un-utilized power that high-density genotyping can provide in the context of map-based WGS sequence reassembly. Our results provide a substantial contribution to the continued improvement of the Populus genome assembly, while demonstrating the feasibility of microarray-based genotyping in a highly heterozygous population. The strategies presented are applicable to genetic mapping efforts in all plant species with similarly high levels of genetic diversity.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19220791?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Khamzina, Asia</style></author><author><style face="normal" font="default" size="100%">Lamers, John P A</style></author><author><style face="normal" font="default" size="100%">Vlek, Paul L G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Nitrogen fixation by Elaeagnus angustifolia in the reclamation of degraded croplands of Central Asia.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">799-808</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Extensive degradation of irrigated croplands, due to increasing soil salinity and depletion of soil nutrient stocks, is a major problem in Central Asia (CA), one of the largest irrigated areas in the world. To assess the potential for improving the productive capacity of degraded lands by afforestation, we examined N(2) fixation of Elaeagnus angustifolia L. in mixed plantations with non-fixing Populus euphratica Oliv. and Ulmus pumila L. Fixation of N(2) was quantified by the (15)N natural abundance technique based on both foliar and whole-plant sampling during five consecutive growing seasons. Despite elevated root-zone soil salinity (6-10 dS m(-1)) and deficiency in plant-available P (4-15 mg kg(-1)), N(2) fixation (%Ndfa) increased from an initial value of 20% to almost 100% over 5 years. Within each growing season, %Ndfa steadily increased and peaked in the fall. Annual N(2) fixation, determined using foliar delta(15)N, initially averaged 0.02 Mg ha(-1), peaked at 0.5 Mg ha(-1) during the next 2 years and thereafter stabilized at 0.3 Mg ha(-1). Estimates based on whole-plant delta(15)N were &lt;10% lower than those based on foliar delta(15)N. The increase in plant-available soil N was significantly higher in E. angustifolia plots than in P. euphratica and U. pumila plots. Increases in the concentrations of organic C (19%), total N (21%) and plant-available P (74%) in the soil were significant irrespective of tree species. This improvement in soil fertility is further evidence that afforestation with mixed-species plantations can be a sustainable land use option for the degraded irrigated croplands in CA.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19324691?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Navajas-Pérez, Rafael</style></author><author><style face="normal" font="default" size="100%">Paterson, Andrew H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Patterns of tandem repetition in plant whole genome assemblies.</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular genetics and genomics : MGG</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Genet. Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">281</style></volume><pages><style face="normal" font="default" size="100%">579-90</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Tandem repeats often confound large genome assemblies. A survey of tandemly arrayed repetitive sequences was carried out in whole genome sequences of the green alga Chlamydomonas reinhardtii, the moss Physcomitrella patens, the monocots rice and sorghum, and the dicots Arabidopsis thaliana, poplar, grapevine, and papaya, in order to test how these assemblies deal with this fraction of DNA. Our results suggest that plant genome assemblies preferentially include tandem repeats composed of shorter monomeric units (especially dinucleotide and 9-30-bp repeats), while higher repetitive units pose more difficulties to assemble. Nevertheless, notwithstanding that currently available sequencing technologies struggle with higher arrays of repeated DNA, major well-known repetitive elements including centromeric and telomeric repeats as well as high copy-number genes, were found to be reasonably well represented. A database including all tandem repeat sequences characterized here was created to benefit future comparative genomic analyses.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19242726?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Häikiö, E</style></author><author><style face="normal" font="default" size="100%">Makkonen, M</style></author><author><style face="normal" font="default" size="100%">Julkunen-Tiitto, R</style></author><author><style face="normal" font="default" size="100%">Sitte, J</style></author><author><style face="normal" font="default" size="100%">Freiwald, V</style></author><author><style face="normal" font="default" size="100%">Silfver, T</style></author><author><style face="normal" font="default" size="100%">Pandey, V</style></author><author><style face="normal" font="default" size="100%">Beuker, E</style></author><author><style face="normal" font="default" size="100%">Holopainen, T</style></author><author><style face="normal" font="default" size="100%">Oksanen, E</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Performance and secondary chemistry of two hybrid aspen (Populus tremula L. x Populus tremuloides Michx.) clones in long-term elevated ozone exposure.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of chemical ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Chem. Ecol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">35</style></volume><pages><style face="normal" font="default" size="100%">664-78</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The effects of moderately elevated ozone (ca. 35 ppb) on the growth and secondary chemistry of the leaves of two soil-grown Finnish hybrid aspen (Populus tremula L. x Populus tremuloides Michx.) clones with different ozone sensitivities were studied at an open-air exposure field in Kuopio, Finland. Stomatal conductance, photosynthetic rate, and chlorophyll fluorescence were measured during the third growing season. Foliar phenolic concentrations, ergosterol concentration of fine roots, and final dry mass of the trees were determined at the end of the third growing season. Elevated ozone increased the ectomycorrhizal status of the fine roots but had no effect on gas exchange or on the final biomass of either of the clones, indicating equal sensitivity to ozone and no effect of elevated ozone on the intraspecific competitive ability of the clones after three growing seasons. However, in agreement with the data from potted plants of the same clones after two growing seasons, significant differences between the clones were found in all parameters measured. A negative correlation between growth and high concentrations of foliar phenolics indicated that allocation to secondary chemistry also was costly in terms of growth under high resource availability.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19462207?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Xiao, Xiangwen</style></author><author><style face="normal" font="default" size="100%">Yang, Fan</style></author><author><style face="normal" font="default" size="100%">Zhang, Sheng</style></author><author><style face="normal" font="default" size="100%">Korpelainen, Helena</style></author><author><style face="normal" font="default" size="100%">Li, Chunyang</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Physiological and proteomic responses of two contrasting Populus cathayana populations to drought stress.</style></title><secondary-title><style face="normal" font="default" size="100%">Physiologia plantarum</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Physiol Plant</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">136</style></volume><pages><style face="normal" font="default" size="100%">150-68</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The acclimation of plants to water deficit is the result of many different physiological and biochemical mechanisms. To gain a better understanding of drought stress acclimation and tolerance mechanisms in Populus cathayana Rehder, we carried out an integrated physiological and comparative proteomic analysis on the drought stress responses of two contrasting populations originating from wet and dry regions in western China. The plantlets were subjected to continuous drought stress by withholding soil water content at 25% of field capacity (FC) for 45 days, while the control treatments were kept at 100% FC. Drought stress significantly inhibited plant growth, decreased net photosynthetic rate and stomatal conductance of leaves, increased the relative electrolyte leakage and malondialdehyde (MDA) content, and, at the same time, accumulated soluble sugars and free proline in both populations tested. The population from the dry climate region exhibited stronger tolerance to drought stress compared with the wet climate population. The proteomic analyses resulted in the identification of 40 drought-responsive proteins. The functional categories of these proteins include the regulation of transcription and translation, photosynthesis, cytoskeleton, secondary metabolism, HSPs/chaperones, redox homeostasis and defense response. The results suggest that poplars' tolerance to drought stress relates to the control of reactive oxygen species (ROS) and to osmoprotective capacity. The differential regulation of some drought-responsive proteins, such as HSPs and the enzymes related to redox homeostasis and regulation of secondary metabolism, plays an important role in poplars' tolerance and acclimation to drought stress. In conclusion, acclimation to water deficit involves changes in cellular metabolism and the regulation of gene networks. The present study not only provides new insights into the mechanisms of acclimation and tolerance to drought stress in different poplar populations but also provides clues for improving poplars' drought tolerance through breeding or genetic engineering.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19453505?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wilske, Burkhard</style></author><author><style face="normal" font="default" size="100%">Lu, Nan</style></author><author><style face="normal" font="default" size="100%">Wei, Long</style></author><author><style face="normal" font="default" size="100%">Chen, Shiping</style></author><author><style face="normal" font="default" size="100%">Zha, Tonggang</style></author><author><style face="normal" font="default" size="100%">Liu, Chenfeng</style></author><author><style face="normal" font="default" size="100%">Xu, Wenting</style></author><author><style face="normal" font="default" size="100%">Noormets, Asko</style></author><author><style face="normal" font="default" size="100%">Huang, Jianhui</style></author><author><style face="normal" font="default" size="100%">Wei, Yafen</style></author><author><style face="normal" font="default" size="100%">Chen, Jun</style></author><author><style face="normal" font="default" size="100%">Zhang, Zhiqiang</style></author><author><style face="normal" font="default" size="100%">Ni, Jian</style></author><author><style face="normal" font="default" size="100%">Sun, Ge</style></author><author><style face="normal" font="default" size="100%">Guo, Kirk</style></author><author><style face="normal" font="default" size="100%">McNulty, Steve</style></author><author><style face="normal" font="default" size="100%">John, Ranjeet</style></author><author><style face="normal" font="default" size="100%">Han, Xingguo</style></author><author><style face="normal" font="default" size="100%">Lin, Guanghui</style></author><author><style face="normal" font="default" size="100%">Chen, Jiquan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Poplar plantation has the potential to alter the water balance in semiarid Inner Mongolia.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of environmental management</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Environ. Manage.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">90</style></volume><pages><style face="normal" font="default" size="100%">2762-70</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Poplar plantation is the most dominant broadleaf forest type in northern China. Since the mid-1990s plantation was intensified to combat desertification along China's northwestern border, i.e., within Inner Mongolia (IM). This evoked much concern regarding the ecological and environmental effects on areas that naturally grow grass or shrub vegetation. To highlight potential consequences of large-scale poplar plantations on the water budget within semiarid IM, we compared the growing season water balance (evapotranspiration (ET) and precipitation (PPT)) of a 3-yr old poplar plantation (Kp(3)) and a natural shrubland (Ks) in the Kubuqi Desert in western IM, and a 6-yr old poplar plantation (Bp(6)) growing under sub-humid climate near Beijing. The results showed that, despite 33% lower PPT at Kp(3), ET was 2% higher at Kp(3) (228 mm) as compared with Ks (223 mm) in May-September 2006. The difference derived mainly from higher ET at the plantation during drier periods of the growing season, which also indicated that the poplars must have partly transpired groundwater. Estimated growing season ET at Bp(6) was about 550 mm and more than 100% higher than at Kp(3). It is estimated that increases in leaf area index and net radiation at Kp(3) provide future potential for the poplars in Kubuqi to exceed the present ET and ET of the natural shrubland by 100-200%. These increases in ET are only possible through the permanent use of groundwater either directly by the trees or through increased irrigation. This may significantly change the water balance in the area (e.g., high ET at the cost of a reduction in the water table), which renders large-scale plantations a questionable tool in sustainable arid-land management.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19375215?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sjödin, Andreas</style></author><author><style face="normal" font="default" size="100%">Street, Nathaniel Robert</style></author><author><style face="normal" font="default" size="100%">Sandberg, Göran</style></author><author><style face="normal" font="default" size="100%">Gustafsson, Petter</style></author><author><style face="normal" font="default" size="100%">Jansson, Stefan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The Populus Genome Integrative Explorer (PopGenIE): a new resource for exploring the Populus genome.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">182</style></volume><pages><style face="normal" font="default" size="100%">1013-25</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Populus has become an important model plant system. However, utilization of the increasingly extensive collection of genetics and genomics data created by the community is currently hindered by the lack of a central resource, such as a model organism database (MOD). Such MODs offer a single entry point to the collection of resources available within a model system, typically including tools for exploring and querying those resources. As a starting point to overcoming the lack of such an MOD for Populus, we present the Populus Genome Integrative Explorer (PopGenIE), an integrated set of tools for exploring the Populus genome and transcriptome. The resource includes genome, synteny and quantitative trait locus (QTL) browsers for exploring genetic data. Expression tools include an electronic fluorescent pictograph (eFP) browser, expression profile plots, co-regulation within collated transcriptomics data sets, and identification of over-represented functional categories and genomic hotspot locations. A number of collated transcriptomics data sets are made available in the eFP browser to facilitate functional exploration of gene function. Additional homology and data extraction tools are provided. PopGenIE significantly increases accessibility to Populus genomics resources and allows exploration of transcriptomics data without the need to learn or understand complex statistical analysis methods. PopGenIE is available at www.popgenie.org or via www.populusgenome.info.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19383103?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Azri, Wassim</style></author><author><style face="normal" font="default" size="100%">Chambon, Christophe</style></author><author><style face="normal" font="default" size="100%">Herbette, Stéphane</style></author><author><style face="normal" font="default" size="100%">Brunel, Nicole</style></author><author><style face="normal" font="default" size="100%">Coutand, Catherine</style></author><author><style face="normal" font="default" size="100%">Leplé, Jean-Charles</style></author><author><style face="normal" font="default" size="100%">Ben Rejeb, Ichrak</style></author><author><style face="normal" font="default" size="100%">Ammar, Saïda</style></author><author><style face="normal" font="default" size="100%">Julien, Jean-Louis</style></author><author><style face="normal" font="default" size="100%">Roeckel-Drevet, Patricia</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Proteome analysis of apical and basal regions of poplar stems under gravitropic stimulation.</style></title><secondary-title><style face="normal" font="default" size="100%">Physiologia plantarum</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Physiol Plant</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">136</style></volume><pages><style face="normal" font="default" size="100%">193-208</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Gravity is a constant force guiding the direction of plant growth. In young poplar stem, reorientation of the apical region is mainly obtained by differential growth of elongating primary tissues. At the base, where elongation is achieved but where the cambium is active, reorientation is due to asymmetrical formation of reaction wood. After 45 min of gravistimulation, the stem showed no reorientation, but 1 week later, reaction wood was observed at the base of the stem. To determine the molecular mechanisms taking place at the top and base of the stem, after 45 min or 1 week of inclination, the changes induced in protein accumulation were studied by two-dimensional polyacrylamide gel electrophoresis and quantitatively analyzed using image analysis software. Around 300 protein spots were reproducibly detected and analyzed. Forty percent of these proteins showed significant changes after inclination. Mass spectrometry analysis of 135 spots led to the identification of 60 proteins involved in a wide range of activities and metabolisms. Very different patterns of protein expression were obtained according to conditions tested, highlighting the complexity of gravitropic responses. Our results suggest that primary and secondary tissues present specific mechanisms to sense reorientation and to respond to inclination. Some selected proteins are discussed.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19453506?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ohmiya, Yasunori</style></author><author><style face="normal" font="default" size="100%">Ono, Toshiro</style></author><author><style face="normal" font="default" size="100%">Taniguchi, Toru</style></author><author><style face="normal" font="default" size="100%">Itahana, Naoei</style></author><author><style face="normal" font="default" size="100%">Ogawa, Naoto</style></author><author><style face="normal" font="default" size="100%">Miyashita, Kiyotaka</style></author><author><style face="normal" font="default" size="100%">Ohmiya, Kunio</style></author><author><style face="normal" font="default" size="100%">Sakka, Kazuo</style></author><author><style face="normal" font="default" size="100%">Kimura, Tetsuya</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Stable expression of the chlorocatechol dioxygenase gene from Ralstonia eutropha NH9 in hybrid poplar cells.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioscience, biotechnology, and biochemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biosci. Biotechnol. Biochem.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">73</style></volume><pages><style face="normal" font="default" size="100%">1425-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The cbnA gene encoding chlorocatechol dioxygenase from the soil bacterium Ralstonia eutropha NH9 under the control of a modified cauliflower mosaic virus 35S promoter was introduced into a hybrid poplar (Populus tremula x P. tremuloides). Integration of the cbnA gene in transgenic poplar was confirmed by PCR and genomic Southern blot analysis. Expression of the cbnA gene was analyzed by Western blot analysis. Transgenic poplar calli efficiently converted 3-chlorocatechol to 2-chloro-cis,cis-muconate.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19502754?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Mellway, Robin D</style></author><author><style face="normal" font="default" size="100%">Tran, Lan T</style></author><author><style face="normal" font="default" size="100%">Prouse, Michael B</style></author><author><style face="normal" font="default" size="100%">Campbell, Malcolm M</style></author><author><style face="normal" font="default" size="100%">Constabel, C Peter</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The wound-, pathogen-, and ultraviolet B-responsive MYB134 gene encodes an R2R3 MYB transcription factor that regulates proanthocyanidin synthesis in poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">150</style></volume><pages><style face="normal" font="default" size="100%">924-41</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In poplar (Populus spp.), the major defense phenolics produced in leaves are the flavonoid-derived proanthocyanidins (PAs) and the salicin-based phenolic glycosides. Transcriptional activation of PA biosynthetic genes leading to PA accumulation in leaves occurs following herbivore damage and mechanical wounding as well as infection by the fungal biotroph Melampsora medusae. In this study, we have identified a poplar R2R3 MYB transcription factor gene, MYB134, that exhibits close sequence similarity to the Arabidopsis (Arabidopsis thaliana) PA regulator TRANSPARENT TESTA2 and that is coinduced with PA biosynthetic genes following mechanical wounding, M. medusae infection, and exposure to elevated ultraviolet B light. Overexpression of MYB134 in poplar resulted in transcriptional activation of the full PA biosynthetic pathway and a significant plant-wide increase in PA levels, and electrophoretic mobility shift assays showed that recombinant MYB134 protein is able to bind to promoter regions of PA pathway genes. MYB134-overexpressing plants exhibited a concomitant reduction in phenolic glycoside concentrations and other minor alterations to levels of small phenylpropanoid metabolites. Our data provide insight into the regulatory mechanisms controlling stress-induced PA metabolism in poplar, and the identification of a regulator of stress-responsive PA biosynthesis constitutes a valuable tool for manipulating PA metabolism in poplar and investigating the biological functions of PAs in resistance to biotic and abiotic stresses.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19395405?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bao, Y</style></author><author><style face="normal" font="default" size="100%">Dharmawardhana, P</style></author><author><style face="normal" font="default" size="100%">Arias, R</style></author><author><style face="normal" font="default" size="100%">Allen, M B</style></author><author><style face="normal" font="default" size="100%">Ma, C</style></author><author><style face="normal" font="default" size="100%">Strauss, Steven H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">WUS and STM-based reporter genes for studying meristem development in poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant cell reports</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Rep.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">947-62</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We describe the development of a reporter system for monitoring meristem initiation in poplar using promoters of poplar homologs to the meristem-active regulatory genes WUSCHEL (WUS) and SHOOTMERISTEMLESS (STM). When ~3 kb of the 5' flanking regions of close homologs were used to drive expression of the GUSPlus gene, 50-60% of the transgenic events showed expression in apical and axillary meristems. However, expression was also common in other organs, including in leaf veins (40 and 46% of WUS and STM transgenic events, respectively) and hydathodes (56% of WUS transgenic events). Histochemical GUS staining of explants during callogenesis and shoot regeneration using in vitro stems as explants showed that expression was detectable prior to visible shoot development, starting 3-15 days after explants were placed onto callus inducing medium. A minority of WUS and STM events also showed expression in the cambium, phloem, or xylem of regenerated, greenhouse grown plants undergoing secondary growth. Based on microarray gene expression data, a paralog of poplar WUS was detectably up-regulated during shoot initiation, but the other paralog was not. Both paralogs of poplar STM were down-regulated threefold to sixfold during early callus initiation. We identified 15-35 copies of cytokinin response regulator binding motifs (ARR1AT) and one copy of the auxin response element (AuxRE) in both promoters. Several of the events recovered may be useful for studying the process of primary and secondary meristem development, including treatments intended to stimulate meristem development to promote clonal propagation and genetic transformation.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19280192?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bae, Eun-Kyung</style></author><author><style face="normal" font="default" size="100%">Lee, Hyoshin</style></author><author><style face="normal" font="default" size="100%">Lee, Jae-Soon</style></author><author><style face="normal" font="default" size="100%">Noh, Eun-Woon</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Differential expression of a poplar SK2-type dehydrin gene in response to various stresses.</style></title><secondary-title><style face="normal" font="default" size="100%">BMB reports</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMB Rep</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jul 31</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">42</style></volume><pages><style face="normal" font="default" size="100%">439-43</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Dehydrins are group II, late embryogenesis abundant proteins that act putatively as chaperones in stressed plants. To elucidate the function of dehydrins in poplar, we isolated the SK(2)-type dehydrin gene Podhn from Populus alba x P. tremula var. glandulosa suspension cells and analyzed its expression following treatments of abiotic stress, wounding and plant growth regulator. Sequence homology and phylogenetic analyses indicate Podhn encodes an acidic dehydrin (pI 5.14, 277 amino acids, predicted size 25.6 kDa) containing two lysine-rich &quot;K-segments&quot; and a 7-serine residue &quot;S-segment&quot;, both characteristic of SK(2)-type dehydrins. Southern blots show Podhn genes form a small gene family in poplar. Podhn was expressed in all tissues examined under unstressed conditions, but most strongly in cell suspensions (especially in the stationary phase). Drought, salt, cold and exogenous abscisic acid (ABA) treatments enhanced Podhn expression, while wounding and jasmonic acid caused its reduction. Therefore, Podhn might be involved in ABA or stress response.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19643042?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Carnegie, D</style></author><author><style face="normal" font="default" size="100%">Ramsay, J A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Anaerobic ethylene glycol degradation by microorganisms in poplar and willow rhizospheres.</style></title><secondary-title><style face="normal" font="default" size="100%">Biodegradation</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biodegradation</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">20</style></volume><pages><style face="normal" font="default" size="100%">551-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Although aerobic degradation of ethylene glycol is well documented, only anaerobic biodegradation via methanogenesis or fermentation has been clearly shown. Enhanced ethylene glycol degradation has been demonstrated by microorganisms in the rhizosphere of shallow-rooted plants such as alfalfa and grasses where conditions may be aerobic, but has not been demonstrated in the deeper rhizosphere of poplar or willow trees where conditions are more likely to be anaerobic. This study evaluated ethylene glycol degradation under nitrate-, and sulphate-reducing conditions by microorganisms from the rhizosphere of poplar and willow trees planted in the path of a groundwater plume containing up to 1.9 mol l(-1) (120 g l(-1)) ethylene glycol and, the effect of fertilizer addition when nitrate or sulphate was provided as a terminal electron acceptor (TEA). Microorganisms in these rhizosphere soils degraded ethylene glycol using nitrate or sulphate as TEAs at close to the theoretical stoichiometric amounts required for mineralization. Although the added nitrate or sulphate was primarily used as TEA, TEAs naturally present in the soil or CO(2) produced from ethylene glycol degradation were also used, demonstrating multiple TEA usage. Anaerobic degradation produced acetaldehyde, less acetic acid, and more ethanol than under aerobic conditions. Although aerobic degradation rates were faster, close to 100% disappearance was eventually achieved anaerobically. Degradation rates under nitrate-reducing conditions were enhanced upon fertilizer addition to achieve rates similar to aerobic degradation with up to 19.3 mmol (1.20 g) of ethylene glycol degradation l(-1) day(-1) in poplar soils. This is the first study to demonstrate that microorganisms in the rhizosphere of deep rooted trees like willow and poplar can anaerobically degrade ethylene glycol. Since anaerobic biodegradation may significantly contribute to the phytoremediation of ethylene glycol in the deeper subsurface, the need for &quot;pump and treat&quot; or an aerobic treatment would be eliminated, hence reducing the cost of treatment.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19132327?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Redford, Amanda J</style></author><author><style face="normal" font="default" size="100%">Fierer, Noah</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Bacterial succession on the leaf surface: a novel system for studying successional dynamics.</style></title><secondary-title><style face="normal" font="default" size="100%">Microbial ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Microb. Ecol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">58</style></volume><pages><style face="normal" font="default" size="100%">189-98</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Succession is a widely studied process in plant and animal systems, but succession in microbial communities has received relatively little attention despite the ubiquity of microorganisms in natural habitats. One important microbial habitat is the phyllosphere, or leaf surface, which harbors large, diverse populations of bacteria and offers unique opportunities for the study of succession and temporal community assembly patterns. To explore bacterial community successional patterns, we sampled phyllosphere communities on cottonwood (Populus deltoides) trees multiple times across the growing season, from leaf emergence to leaf fall. Bacterial community composition was highly variable throughout the growing season; leaves sampled as little as a week apart were found to harbor significantly different communities, and the temporal variability on a given tree exceeded the variability in community composition between individual trees sampled on a given day. The bacterial communities clearly clustered into early-, mid-, and late-season clusters, with early- and late-season communities being more similar to each other than to the mid-season communities, and these patterns appeared consistent from year to year. Although we observed clear and predictable changes in bacterial community composition during the course of the growing season, changes in phyllosphere bacterial diversity were less predictable. We examined the species-time relationship, a measure of species turnover rate, and found that the relationship was fundamentally similar to that observed in plant and invertebrate communities, just on a shorter time scale. The temporal dynamics we observed suggest that although phyllosphere bacterial communities have high levels of phylogenetic diversity and rapid turnover rates, these communities follow predictable successional patterns from season to season.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19221834?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Yu, Xiao-Hong</style></author><author><style face="normal" font="default" size="100%">Gou, Jin-Ying</style></author><author><style face="normal" font="default" size="100%">Liu, Chang-Jun</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">BAHD superfamily of acyl-CoA dependent acyltransferases in Populus and Arabidopsis: bioinformatics and gene expression.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Mol. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">70</style></volume><pages><style face="normal" font="default" size="100%">421-42</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Plant acyl-CoA dependent acyltransferases constitute a large specific protein superfamily, named BAHD. Using the conserved sequence motifs of BAHD members, we searched the genome sequences of Populus and Arabidopsis, and identified, respectively, 94- and 61-putative genes. Subsequently, we analyzed the phylogeny, gene structure, and chromosomal distribution of BAHD members of both species; then, we profiled expression patterns of BAHD genes by &quot;in silico&quot; northern- and microarray-analyses based on public databases, and by RT-PCR. While our genomic- and bioinformatic- analyses provided full sets of BAHD superfamily genes, and cleaned up a few existing annotation errors, importantly it led to our recognizing several unique Arabidopsis BAHD genes that inversely overlapped with their neighboring genes on the genome, and disclosing a potential natural anti-sense regulation for gene expressions. Systemic gene-expression profiling of BAHD members revealed distinct tissue-specific/preferential expression patterns, indicating their diverse biological functions. Our study affords a strong knowledge base for understanding BAHD members' evolutionary relationships and gene functions implicated in plant growth, development and metabolism.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19343509?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Diner, Brandee</style></author><author><style face="normal" font="default" size="100%">Berteaux, Dominique</style></author><author><style face="normal" font="default" size="100%">Fyles, Jim</style></author><author><style face="normal" font="default" size="100%">Lindroth, Richard L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Behavioral archives link the chemistry and clonal structure of trembling aspen to the food choice of North American porcupine.</style></title><secondary-title><style face="normal" font="default" size="100%">Oecologia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Oecologia</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">160</style></volume><pages><style face="normal" font="default" size="100%">687-95</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Understanding the links among plant genotype, plant chemistry, and food selection by vertebrate herbivores is critical to assess the role of herbivores in the evolution of plant secondary chemistry. Some specialized vertebrate herbivores have been shown to select plants differentially according to plant genotype, but examples from generalists, which constitute the vast majority of vertebrate herbivores, are few, especially in natural conditions. We examined the relationship between the North American porcupine (Erethizon dorsatum), a generalist mammalian herbivore, and clonal trembling aspen (Populus tremuloides), a preferred food source of porcupines. We determined preference for certain aspen trees through visual examination of porcupine climbing scars left on tree bark, and through a controlled feeding experiment. We used genetic and biochemical analyses to link the behavioral archives (climbing scars) left by porcupines on aspen trunks to the clonal structure and chemical composition of trees. We show that two phenolic glycosides (tremulacin and salicortin), which are under a high degree of genetic control and thus vary in concentration across clones, are the chemical variables that most influence (deter) feeding choices by porcupines. Using behavioral archives left by a wild herbivore on a natural stand of plants thus allowed us to demonstrate that a generalist vertebrate herbivore can choose plants according to their clonal structure and genetically based chemical composition. Our results contribute to extending previous findings obtained with generalist herbivores studied in controlled conditions, and with specialist herbivores studied in the field.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19390868?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Jardine, K</style></author><author><style face="normal" font="default" size="100%">Karl, T</style></author><author><style face="normal" font="default" size="100%">Lerdau, M</style></author><author><style face="normal" font="default" size="100%">Harley, P</style></author><author><style face="normal" font="default" size="100%">Guenther, A</style></author><author><style face="normal" font="default" size="100%">Mak, J E</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Carbon isotope analysis of acetaldehyde emitted from leaves following mechanical stress and anoxia.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant biology (Stuttgart, Germany)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Biol (Stuttg)</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">11</style></volume><pages><style face="normal" font="default" size="100%">591-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Although the emission of acetaldehyde from plants into the atmosphere following biotic and abiotic stresses may significantly impact air quality and climate, its metabolic origin(s) remains uncertain. We investigated the pathway(s) responsible for the production of acetaldehyde in plants by studying variations in the stable carbon isotope composition of acetaldehyde emitted during leaf anoxia or following mechanical stress. Under an anoxic environment, C3 leaves produced acetaldehyde during ethanolic fermentation with a similar carbon isotopic composition to C3 bulk biomass. In contrast, the initial emission burst following mechanical wounding was 5-12 per thousand more depleted in (13)C than emissions under anoxia. Due to a large kinetic isotope effect during pyruvate decarboxylation catalysed by pyruvate dehydrogenase, acetyl-CoA and its biosynthetic products such as fatty acids are also depleted in (13)C relative to bulk biomass. It is well known that leaf wounding stimulates the release of large quantities of fatty acids from membranes, as well as the accumulation of reactive oxygen species (ROS). We suggest that, following leaf wounding, acetaldehyde depleted in (13)C is produced from fatty acid peroxidation reactions initiated by the accumulation of ROS. However, a variety of other pathways could also explain our results, including the conversion of acetyl-CoA to acetaldehyde by the esterase activity of aldehyde dehydrogenase.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19538397?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zalesny, Jill A</style></author><author><style face="normal" font="default" size="100%">Zalesny, Ronald S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Chloride and sodium uptake potential over an entire rotation of Populus irrigated with landfill leachate.</style></title><secondary-title><style face="normal" font="default" size="100%">International journal of phytoremediation</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Int J Phytoremediation</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">11</style></volume><pages><style face="normal" font="default" size="100%">496-508</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">There is a need for information about the response of Populus genotypes to repeated application of high-salinity water and nutrient sources throughout an entire rotation. We have combined establishment biomass and uptake data with mid- and full-rotation growth data to project potential chloride (Cl-) and sodium (Na+) uptake for 2- to 11-year-old Populus in the north central United States. Our objectives were to identify potential levels of uptake as the trees developed and stages of plantation development that are conducive to variable application rates of high-salinity irrigation. The projected cumulative uptake of Cl- and Na+ during mid-rotation plantation development was stable 2 to 3 years after planting but increased steadily from year 3 to 6. Year six cumulative uptake ranged from 22 to 175 kg Cl- ha(-1) and 8 to 74 kg Na+ ha(-1), while annual uptake ranged from 8 to 54 kg Cl- ha(-1) yr(-1) and 3 to 23 kg Na+ ha(-1) yr(-1). Full-rotation uptake was greatest from 4 to 9 years (Cl-) and 4 to 8 years (Na+), with maximum levels of Cl- (32 kg ha(-1) yr(-1)) and Na+ (13 kg ha(-1) yr(-1)) occurring in year six. The relative uptake potential of Cl- and Na+ at peak accumulation (year six) was 2.7 times greater than at the end of the rotation.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19810351?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ivanova, L A</style></author><author><style face="normal" font="default" size="100%">Ronzhina, D A</style></author><author><style face="normal" font="default" size="100%">Ivanov, L A</style></author><author><style face="normal" font="default" size="100%">Stroukova, L V</style></author><author><style face="normal" font="default" size="100%">Peuke, A D</style></author><author><style face="normal" font="default" size="100%">Rennenberg, H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Chloroplast parameters differ in wild type and transgenic poplars overexpressing gsh1 in the cytosol.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant biology (Stuttgart, Germany)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Biol (Stuttg)</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">11</style></volume><pages><style face="normal" font="default" size="100%">625-30</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Poplar mutants overexpressing the bacterial genes gsh1 or gsh2 encoding the enzymes of glutathione biosynthesis are among the best-characterised transgenic plants. However, this characterisation originates exclusively from laboratory studies, and the performance of these mutants under field conditions is largely unknown. Here, we report a field experiment in which the wild-type poplar hybrid Populus tremula x P. alba and a transgenic line overexpressing the bacterial gene gsh1 encoding gamma-glutamylcysteine synthetase in the cytosol were grown for 3 years at a relatively clean (control) field site and a field site contaminated with heavy metals. Aboveground biomass accumulation was slightly smaller in transgenic compared to wild-type plants; soil contamination significantly decreased biomass accumulation in both wild-type and transgenic plants by more than 40%. Chloroplasts parameters, i.e., maximal diameter, projection area and perimeter, surface area and volume, surface/volume ratio and a two-dimensional form coefficient, were found to depend on plant type, leaf tissue and soil contamination. The greatest differences between wild and transgenic poplars were observed at the control site. Under these conditions, chloroplast sizes in palisade tissue of transgenic poplar significantly exceeded those of the wild type. In contrast to the wild type, palisade chloroplast volume exceeded that of spongy chloroplasts in transgenic poplars at both field sites. Chlorophyll content per chloroplast was the same in wild and transgenic poplars. Apparently, the increase in chloroplast volume was not connected to changes in the photosynthetic centres. Chloroplasts of transgenic poplar at the control site were more elongated in palisade cells and close to spherical in spongy mesophyll chloroplasts. At the contaminated site, palisade and spongy cell chloroplasts of leaves from transgenic trees and the wild type were the same shape. Transgenic poplars also had a smaller chloroplast surface/volume ratio, both at the control and the contaminated site. Chloroplast number per cell did not differ between wild and transgenic poplars at the control site. Soil contamination led to suppression of chloroplast replication in wild-type plants. From these results, we assume that overexpressing the bacterial gsh1 gene in the cytosol interacts with processes in the chloroplast and that sequestration of heavy metal phytochelatin complexes into the vacuole may partially counteract this interaction in plants grown at heavy metal-contaminated field sites. Further experiments are required to test these assumptions.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19538400?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Castiglione, S</style></author><author><style face="normal" font="default" size="100%">Todeschini, V</style></author><author><style face="normal" font="default" size="100%">Franchin, C</style></author><author><style face="normal" font="default" size="100%">Torrigiani, P</style></author><author><style face="normal" font="default" size="100%">Gastaldi, D</style></author><author><style face="normal" font="default" size="100%">Cicatelli, A</style></author><author><style face="normal" font="default" size="100%">Rinaudo, C</style></author><author><style face="normal" font="default" size="100%">Berta, G</style></author><author><style face="normal" font="default" size="100%">Biondi, S</style></author><author><style face="normal" font="default" size="100%">Lingua, G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Clonal differences in survival capacity, copper and zinc accumulation, and correlation with leaf polyamine levels in poplar: a large-scale field trial on heavily polluted soil.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">157</style></volume><pages><style face="normal" font="default" size="100%">2108-17</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Three ex situ collections of poplar clones from natural populations of Populus alba and P. nigra growing in northern Italy were assessed for their genetic dissimilarity (GD) by means of amplified fragment length polymorphism (AFLP). The high GD evidenced within populations was exploited for screening 168 clones in a field trial on heavy metal-polluted soil. After one growth season, clonal differences in plant survival and growth were observed. On the basis of performance, six clones were singled out, and used to evaluate copper and zinc accumulation in different organs. Clonal differences in metal concentrations were most evident for leaves and stems; one clone of P. alba (AL35) had a distinctly higher concentration of both metals in the roots. Leaf polyamine (putrescine, spermidine, spermine) profiles correlated with tissue metal concentrations, depending on the clone, plant organ and metal. In particular, the high metal-accumulating clone AL35 exhibited a dramatically higher concentration of free and conjugated putrescine. Overall, the results indicate that, given the high GD of Populus even within populations, it is possible to identify genotypes best suited for soil clean-up, and useful also for investigating physiological markers associated with high metal accumulation/tolerance.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19285369?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Harner, Mary J</style></author><author><style face="normal" font="default" size="100%">Crenshaw, Chelsea L</style></author><author><style face="normal" font="default" size="100%">Abelho, Manuela</style></author><author><style face="normal" font="default" size="100%">Stursova, Martina</style></author><author><style face="normal" font="default" size="100%">Shah, Jennifer J Follstad</style></author><author><style face="normal" font="default" size="100%">Sinsabaugh, Robert L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Decomposition of leaf litter from a native tree and an actinorhizal invasive across riparian habitats.</style></title><secondary-title><style face="normal" font="default" size="100%">Ecological applications : a publication of the Ecological Society of America</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ecol Appl</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">19</style></volume><pages><style face="normal" font="default" size="100%">1135-46</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Dynamics of nutrient exchange between floodplains and rivers have been altered by changes in flow management and proliferation of nonnative plants. We tested the hypothesis that the nonnative, actinorhizal tree, Russian olive (Elaeagnus angustifolia), alters dynamics of leaf litter decomposition compared to native cottonwood (Populus deltoides ssp. wislizeni) along the Rio Grande, a river with a modified flow regime, in central New Mexico (U.S.A.). Leaf litter was placed in the river channel and the surface and subsurface horizons of forest soil at seven riparian sites that differed in their hydrologic connection to the river. All sites had a cottonwood canopy with a Russian olive-dominated understory. Mass loss rates, nutrient content, fungal biomass, extracellular enzyme activities (EEA), and macroinvertebrate colonization were followed for three months in the river and one year in forests. Initial nitrogen (N) content of Russian olive litter (2.2%) was more than four times that of cottonwood (0.5%). Mass loss rates (k; in units of d(-1)) were greatest in the river (Russian olive, k = 0.0249; cottonwood, k = 0.0226), intermediate in subsurface soil (Russian olive, k = 0.0072; cottonwood, k = 0.0031), and slowest on the soil surface (Russian olive, k = 0.0034; cottonwood, k = 0.0012) in a ratio of about 10:2:1. Rates of mass loss in the river were indistinguishable between species and proportional to macroinvertebrate colonization. In the riparian forest, Russian olive decayed significantly faster than cottonwood in both soil horizons. Terrestrial decomposition rates were related positively to EEA, fungal biomass, and litter N, whereas differences among floodplain sites were related to hydrologic connectivity with the river. Because nutrient exchanges between riparian forests and the river have been constrained by flow management, Russian olive litter represents a significant annual input of N to riparian forests, which now retain a large portion of slowly decomposing cottonwood litter with a high potential for N immobilization. As a result, retention and mineralization of litter N within these forests is controlled by hydrologic connectivity to the river, which affects litter export and in situ decomposition.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19688922?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Barac, Tanja</style></author><author><style face="normal" font="default" size="100%">Weyens, Nele</style></author><author><style face="normal" font="default" size="100%">Oeyen, Licy</style></author><author><style face="normal" font="default" size="100%">Taghavi, Safiyh</style></author><author><style face="normal" font="default" size="100%">van der Lelie, Daniel</style></author><author><style face="normal" font="default" size="100%">Dubin, Dirk</style></author><author><style face="normal" font="default" size="100%">Spliet, Marco</style></author><author><style face="normal" font="default" size="100%">Vangronsveld, Jaco</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Field note: hydraulic containment of a BTEX plume using poplar trees.</style></title><secondary-title><style face="normal" font="default" size="100%">International journal of phytoremediation</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Int J Phytoremediation</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">11</style></volume><pages><style face="normal" font="default" size="100%">416-24</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In 1999, 275 poplar trees were planted on a field site near a car factory in order to install a bioscreen. The aim was to combine the biodegradation activities of poplar and its associated rhizosphere and endophytic microorganisms for containing a BTEX contaminated groundwater plume. This BTEX plume occurred as the result of leaking solvents and fuel storage tanks. Monitoring, conducted overa 6-year period (1999-2005) after the planting of the trees suggested that the poplar trees and their associated microorganisms had, once the tree roots reached the contaminated groundwater zone, an active role in the remediation of the BTEX plume, resulting in full containment of the contamination. Analysis of the microbial communities associated with poplar demonstrated that, once the poplar roots got in contact with the BTEX contaminated groundwater, enrichment occurred of both rhizosphere and endophytic bacteria that were able to degrade toluene. Interestingly, once the BTEX plume was remediated, the numbers of toluene degrading rhizosphere and endophytic bacteria decreased below the detection limit, indicating that their population resulted from selective enrichment by the presence of the contaminants.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19810345?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Nguyen, T</style></author><author><style face="normal" font="default" size="100%">Drotar, A-M</style></author><author><style face="normal" font="default" size="100%">Monson, R K</style></author><author><style face="normal" font="default" size="100%">Fall, R</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A high affinity pyruvate decarboxylase is present in cottonwood leaf veins and petioles: a second source of leaf acetaldehyde emission?</style></title><secondary-title><style face="normal" font="default" size="100%">Phytochemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Phytochemistry</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">70</style></volume><pages><style face="normal" font="default" size="100%">1217-21</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Considerable evidence indicates that acetaldehyde is released from the leaves of a variety of plants. The conventional explanation for this is that ethanol formed in the roots is transported to the leaves where it is converted to acetaldehyde by the alcohol dehydrogenase (ADH) found in the leaves. It is possible that acetaldehyde could also be formed in leaves by action of pyruvate decarboxylase (PDC), an enzyme with an uncertain metabolic role, which has been detected, but not characterized, in cottonwood leaves. We have found that leaf PDC is present in leaf veins and petioles, as well as in non-vein tissues. Veins and petioles contained measurable pyruvate concentrations in the range of 2mM. The leaf vein form of the enzyme was purified approximately 143-fold, and, at the optimum pH of 5.6, the K(m) value for pyruvate was 42 microM. This K(m) is lower than the typical millimolar range seen for PDCs from other sources. The purified leaf PDC also decarboxylates 2-ketobutyric acid (K(m)=2.2mM). We conclude that there are several possible sources of acetaldehyde production in cottonwood leaves: the well-characterized root-derived ethanol oxidation by ADH in leaves, and the decarboxylation of pyruvate by PDC in leaf veins, petioles, and other leaf tissues. Significantly, the leaf vein form of PDC with its high affinity for pyruvate, could function to shunt pyruvate carbon to the pyruvate dehydrogenase by-pass and thus protect the metabolically active vascular bundle cells from the effects of oxygen deprivation.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19698964?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Balestrazzi, Alma</style></author><author><style face="normal" font="default" size="100%">Bonadei, Martina</style></author><author><style face="normal" font="default" size="100%">Calvio, Cinzia</style></author><author><style face="normal" font="default" size="100%">Mattivi, Fulvio</style></author><author><style face="normal" font="default" size="100%">Carbonera, Daniela</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Leaf-associated bacteria from transgenic white poplar producing resveratrol-like compounds: isolation, molecular characterization, and evaluation of oxidative stress tolerance.</style></title><secondary-title><style face="normal" font="default" size="100%">Canadian journal of microbiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Can. J. Microbiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">55</style></volume><pages><style face="normal" font="default" size="100%">829-40</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The aim of this study was the isolation and characterization of the culturable bacteria inhabiting the leaves of transgenic white poplars (Populus alba L. 'Villafranca') engineered with the StSy gene for the production of resveratrol-like compounds. Resveratrol glucosides are available in small amounts from natural sources or by expensive chemical synthesis procedures. An alternative approach for the large-scale production of these relevant pharmaceuticals is the use of transgenic plants as bioreactors, although the occurrence of novel molecules in plants growing under field conditions might interfere, to some extent, with the associated microbial population. Both epiphytes and endophytes were isolated from the leaves of 2 StSy transgenic lines producing resveratrol glucosides and from an untransformed plant line grown in a greenhouse. Eleven isolates were recovered and classified as members of the genus Bacillus by 16S rDNA-based analysis. In addition, 2 isolates were classified as members of the Curtobacterium and Kocuria genera, respectively. Tolerance to hydrogen peroxide, UV-C, and paraquat was evaluated, as were the swimming and swarming motility of the leaf-associated bacteria. Interestingly, the isolates recovered from transgenic tissues showed the ability to withstand oxidative stress compared with isolates recovered from the untransformed poplar line. In vitro bioassays showed that trans-resveratrol inhibited both the swarming and swimming motilities in all the tested bacteria. The effects of trans-resveratrol on flagellin production, required for motility, were also investigated by immunoblot analysis.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19767855?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wiberley, Amy E</style></author><author><style face="normal" font="default" size="100%">Donohue, Autumn R</style></author><author><style face="normal" font="default" size="100%">Westphal, Maiken M</style></author><author><style face="normal" font="default" size="100%">Sharkey, Thomas D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Regulation of isoprene emission from poplar leaves throughout a day.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">32</style></volume><pages><style face="normal" font="default" size="100%">939-47</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Isoprene is a biogenic hydrocarbon that significantly affects tropospheric chemistry. Numerous plant species, including many trees, emit isoprene. Isoprene is synthesized by isoprene synthase (IspS), from dimethylallyl diphosphate (DMADP) made by the methylerythritol 4-phosphate (MEP) pathway. It has been demonstrated that in developing leaves, isoprene emission is regulated by transcriptional control of IspS, while in mature leaves subjected to changing growth temperature, regulation of emission is shared between IspS and DMADP supply from the MEP pathway. Isoprene emission also varies throughout a day, with circadian regulation implicated. This study investigated changes in isoprene emission capacity, and expression of IspS and the enzymes of the MEP pathway throughout several days, with Populus trichocarpa grown at different temperatures to induce different levels of isoprene emission. Isoprene emission capacity exhibited ultradian regulation, with a period of about 12 h; peak capacity was observed at 0300 and 1500 h daily. Several of the enzymes of the MEP pathway had previously been suggested to have regulatory roles in the production of other plastidic terpenoids, and transcript accumulation for these enzymes, combined with in silico promoter analyses, supported a regulatory role for deoxyxylulose 5-phosphate synthase (DXS) in particular.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19389050?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Budija, Franc</style></author><author><style face="normal" font="default" size="100%">Tavzes, Crtomir</style></author><author><style face="normal" font="default" size="100%">Zupancic-Kralj, Lucija</style></author><author><style face="normal" font="default" size="100%">Petric, Marko</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Self-crosslinking and film formation ability of liquefied black poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioresource technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bioresour. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">100</style></volume><pages><style face="normal" font="default" size="100%">3316-23</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Black poplar wood, diethylene glycol (DEG), and sulphuric acid as a catalyst were used as starting reactants for liquefaction. Optimal conditions for liquefaction were established: reaction temperature 150 degrees C, reaction time 95min, ratio of wood:DEG=1:5 and 3% of sulphuric acid addition. The liquid mixture obtained by the liquefaction was composed of the real product of the reaction (the so called &quot;excess solvent free liquefied wood&quot; (ESFLW)) and of the remaining unreacted DEG. The unreacted DEG was successfully separated from the ESFLW and analysed with HPLC for levulinic acid content. Theoretical weight ratio between the wood and DEG required for the reaction was estimated. OH number investigation showed that the ESFLW in the liquid mixture contributes to maximally 60% of the free_OH groups. The crosslinking of the ESFLW without any curing agents or additives was performed for the first time, and the drying stages investigated. FT-IR investigations demonstrated that the obtained crosslinked polymer film could be an ether and/or ester network.</style></abstract><issue><style face="normal" font="default" size="100%">13</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19272771?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Park, Ji-Young</style></author><author><style face="normal" font="default" size="100%">Canam, Thomas</style></author><author><style face="normal" font="default" size="100%">Kang, Kyu-Young</style></author><author><style face="normal" font="default" size="100%">Unda, Faride</style></author><author><style face="normal" font="default" size="100%">Mansfield, Shawn D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Sucrose phosphate synthase expression influences poplar phenology.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">937-46</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The objective of this study was to manipulate the intracellular pools of sucrose, and investigate its role in regulating plant growth, phenology (leaf senescence and bud break) and fibre development. This objective was achieved by differentially expressing an Arabidopsis (Arabidopsis thaliana L. Heynh.) sucrose phosphate synthase (SPS) gene in hybrid poplar (Populus alba L.xPopulus grandidentata Michx.), a model system for tree biology with substantial industrial relevance in the context of short rotation forestry and a target bioenergy crop. Phenotypic differences were evident in the transgenic trees, as both the timing of bud flush and leaf senescence were altered compared to wild-type (WT) trees. Tree height and stem diameter were similar in WT and in the AtSPS transgenic trees, however, there were differences in the length of xylem fibres. Elevated concentrations of intracellular sucrose in both leaf and stem tissue of the transgenic trees are associated with a prolonged onset of senescence and an advancement in bud flush in the following spring. The association among sucrose content, tree phenology and elevated SPS gene expression implicates both enzyme and product in regulating poplar developmental processes.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19429901?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Guo, Xiao-Hong</style></author><author><style face="normal" font="default" size="100%">Jiang, Jing</style></author><author><style face="normal" font="default" size="100%">Lin, Shi-Jie</style></author><author><style face="normal" font="default" size="100%">Wang, Bai-Chen</style></author><author><style face="normal" font="default" size="100%">Wang, Yu-Cheng</style></author><author><style face="normal" font="default" size="100%">Liu, Gui-Feng</style></author><author><style face="normal" font="default" size="100%">Yang, Chuan-Ping</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A ThCAP gene from Tamarix hispida confers cold tolerance in transgenic Populus (P. davidiana x P. bolleana).</style></title><secondary-title><style face="normal" font="default" size="100%">Biotechnology letters</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biotechnol. Lett.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">31</style></volume><pages><style face="normal" font="default" size="100%">1079-87</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The ThCAP gene, which encodes a cold acclimation protein, was isolated from a Tamarix hispida NaCl-stress root cDNA library; its expression patterns were then assayed by qRT-PCR in different T. hispida tissues treated with low temperature (4 degrees C), salt (400 mM NaCl), drought (20% PEG6000) and exogenous abscisic acid (100 microM). Induction of ThCAP gene was not only responsive to different stress conditions but was also organ specific. When transgenic Populus (P. davidiana x P. bolleana) plants were generated, expressing ThCAP under regulation of the cauliflower mosaic virus CaMV 35S promoter, they had a greater resistance to low temperature than non-transgenic seedlings, suggesting that ThCAP might play an important role in cold tolerance.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19267235?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Paterson, Andrew H</style></author><author><style face="normal" font="default" size="100%">Bowers, John E</style></author><author><style face="normal" font="default" size="100%">Bruggmann, Rémy</style></author><author><style face="normal" font="default" size="100%">Dubchak, Inna</style></author><author><style face="normal" font="default" size="100%">Grimwood, Jane</style></author><author><style face="normal" font="default" size="100%">Gundlach, Heidrun</style></author><author><style face="normal" font="default" size="100%">Haberer, Georg</style></author><author><style face="normal" font="default" size="100%">Hellsten, Uffe</style></author><author><style face="normal" font="default" size="100%">Mitros, Therese</style></author><author><style face="normal" font="default" size="100%">Poliakov, Alexander</style></author><author><style face="normal" font="default" size="100%">Schmutz, Jeremy</style></author><author><style face="normal" font="default" size="100%">Spannagl, Manuel</style></author><author><style face="normal" font="default" size="100%">Tang, Haibao</style></author><author><style face="normal" font="default" size="100%">Wang, Xiyin</style></author><author><style face="normal" font="default" size="100%">Wicker, Thomas</style></author><author><style face="normal" font="default" size="100%">Bharti, Arvind K</style></author><author><style face="normal" font="default" size="100%">Chapman, Jarrod</style></author><author><style face="normal" font="default" size="100%">Feltus, F Alex</style></author><author><style face="normal" font="default" size="100%">Gowik, Udo</style></author><author><style face="normal" font="default" size="100%">Grigoriev, Igor V</style></author><author><style face="normal" font="default" size="100%">Lyons, Eric</style></author><author><style face="normal" font="default" size="100%">Maher, Christopher A</style></author><author><style face="normal" font="default" size="100%">Martis, Mihaela</style></author><author><style face="normal" font="default" size="100%">Narechania, Apurva</style></author><author><style face="normal" font="default" size="100%">Otillar, Robert P</style></author><author><style face="normal" font="default" size="100%">Penning, Bryan W</style></author><author><style face="normal" font="default" size="100%">Salamov, Asaf A</style></author><author><style face="normal" font="default" size="100%">Wang, Yu</style></author><author><style face="normal" font="default" size="100%">Zhang, Lifang</style></author><author><style face="normal" font="default" size="100%">Carpita, Nicholas C</style></author><author><style face="normal" font="default" size="100%">Freeling, Michael</style></author><author><style face="normal" font="default" size="100%">Gingle, Alan R</style></author><author><style face="normal" font="default" size="100%">Hash, C Thomas</style></author><author><style face="normal" font="default" size="100%">Keller, Beat</style></author><author><style face="normal" font="default" size="100%">Klein, Patricia</style></author><author><style face="normal" font="default" size="100%">Kresovich, Stephen</style></author><author><style face="normal" font="default" size="100%">McCann, Maureen C</style></author><author><style face="normal" font="default" size="100%">Ming, Ray</style></author><author><style face="normal" font="default" size="100%">Peterson, Daniel G</style></author><author><style face="normal" font="default" size="100%">Peterson, Daniel G</style></author><author><style face="normal" font="default" size="100%">Ware, Doreen</style></author><author><style face="normal" font="default" size="100%">Westhoff, Peter</style></author><author><style face="normal" font="default" size="100%">Mayer, Klaus F X</style></author><author><style face="normal" font="default" size="100%">Messing, Joachim</style></author><author><style face="normal" font="default" size="100%">Rokhsar, Daniel S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The Sorghum bicolor genome and the diversification of grasses.</style></title><secondary-title><style face="normal" font="default" size="100%">Nature</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Nature</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan 29</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">457</style></volume><pages><style face="normal" font="default" size="100%">551-6</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Sorghum, an African grass related to sugar cane and maize, is grown for food, feed, fibre and fuel. We present an initial analysis of the approximately 730-megabase Sorghum bicolor (L.) Moench genome, placing approximately 98% of genes in their chromosomal context using whole-genome shotgun sequence validated by genetic, physical and syntenic information. Genetic recombination is largely confined to about one-third of the sorghum genome with gene order and density similar to those of rice. Retrotransposon accumulation in recombinationally recalcitrant heterochromatin explains the approximately 75% larger genome size of sorghum compared with rice. Although gene and repetitive DNA distributions have been preserved since palaeopolyploidization approximately 70 million years ago, most duplicated gene sets lost one member before the sorghum-rice divergence. Concerted evolution makes one duplicated chromosomal segment appear to be only a few million years old. About 24% of genes are grass-specific and 7% are sorghum-specific. Recent gene and microRNA duplications may contribute to sorghum's drought tolerance.</style></abstract><issue><style face="normal" font="default" size="100%">7229</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19189423?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Xu, Guixia</style></author><author><style face="normal" font="default" size="100%">Ma, Hong</style></author><author><style face="normal" font="default" size="100%">Nei, Masatoshi</style></author><author><style face="normal" font="default" size="100%">Kong, Hongzhi</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Evolution of F-box genes in plants: different modes of sequence divergence and their relationships with functional diversification.</style></title><secondary-title><style face="normal" font="default" size="100%">Proceedings of the National Academy of Sciences of the United States of America</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Proc. Natl. Acad. Sci. U.S.A.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan 20</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">106</style></volume><pages><style face="normal" font="default" size="100%">835-40</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">F-box proteins are substrate-recognition components of the Skp1-Rbx1-Cul1-F-box protein (SCF) ubiquitin ligases. In plants, F-box genes form one of the largest multigene superfamilies and control many important biological functions. However, it is unclear how and why plants have acquired a large number of F-box genes. Here we identified 692, 337, and 779 F-box genes in Arabidopsis, poplar and rice, respectively, and studied their phylogenetic relationships and evolutionary patterns. We found that the plant F-box superfamily can be divided into 42 families, each of which has a distinct domain organization. We also estimated the number of ancestral genes for each family and identified highly conservative versus divergent families. In conservative families, there has been little or no change in the number of genes since the divergence between eudicots and monocots approximately 145 million years ago. In divergent families, however, the numbers have increased dramatically during the same period. In two cases, the numbers of genes in extant species are &gt;100 times greater than that in the most recent common ancestor (MRCA) of the three species. Proteins encoded by highly conservative genes always have the same domain organization, suggesting that they interact with the same or similar substrates. In contrast, proteins of rapidly duplicating genes sometimes have quite different domain structures, mainly caused by unusually frequent shifts of exon-intron boundaries and/or frameshift mutations. Our results indicate that different F-box families, or different clusters of the same family, have experienced dramatically different modes of sequence divergence, apparently having resulted in adaptive changes in function.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19126682?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Chen, Jinhuan</style></author><author><style face="normal" font="default" size="100%">Xia, Xinli</style></author><author><style face="normal" font="default" size="100%">Yin, Weilun</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Expression profiling and functional characterization of a DREB2-type gene from Populus euphratica.</style></title><secondary-title><style face="normal" font="default" size="100%">Biochemical and biophysical research communications</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biochem. Biophys. Res. Commun.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan 16</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">378</style></volume><pages><style face="normal" font="default" size="100%">483-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A novel DREB (dehydration responsive element binding) gene, designated PeDREB2, was isolated from the desert-grown tree, Populus euphratica. Based on multiple sequence alignment and phylogenetic characterization, PeDREB2 was classified as an A-2 group member of the DREB family. Expression of PeDREB2 was induced by cold, drought, and high salinity, but not by abscisic acid (ABA) treatment. PeDREB2 could bind specifically to DRE elements and was targeted to the nucleus when transiently expressed in onion epidermis cells. 35S promoter-driven expression of PeDREB2 improved salt tolerance in transgenic tobacco and did not cause growth retardation. The results indicate that PeDREB2 functions as a novel transcription factor involved in the response of salt stress and might be useful in improving salt tolerance in transgenic plants.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19032934?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Dhadi, Surendar Reddy</style></author><author><style face="normal" font="default" size="100%">Krom, Nicholas</style></author><author><style face="normal" font="default" size="100%">Ramakrishna, Wusirika</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genome-wide comparative analysis of putative bidirectional promoters from rice, Arabidopsis and Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">Gene</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Gene</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan 15</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">429</style></volume><pages><style face="normal" font="default" size="100%">65-73</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A bidirectional promoter can regulate the expression of two flanking genes arranged in a divergent manner. Although reports pertaining to bidirectional promoters on a genomic scale exist in mammals, little progress has been made in plants. In the present study, we performed a computational analysis of this unique class of promoters to identify overrepresented cis-regulatory motifs from three sequenced plant genomes: rice (Oryza sativa), Arabidopsis thaliana, and Populus trichocarpa using the Plant Cis-acting Regulatory DNA Elements (PLACE) and PLANT CARE databases. We describe these overrepresented elements and their possible regulatory mechanisms. We also discuss similarities and differences with human bidirectional promoters. Furthermore, we describe in detail a few coexpressed and evolutionarily conserved divergent gene pairs and their bidirectional promoters. This study provides insights into bidirectional promoters in three plant species, thereby laying a foundation for their experimental analysis.</style></abstract><issue><style face="normal" font="default" size="100%">1-2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18973799?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Khabir, Z H</style></author><author><style face="normal" font="default" size="100%">Sadeghi, S E</style></author><author><style face="normal" font="default" size="100%">Hanifeh, S</style></author><author><style face="normal" font="default" size="100%">Eivazi, A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Investigation on effect of Populus alba stands distance on density of pests and their natural enemies population under poplar/alfalfa agroforestry system.</style></title><secondary-title><style face="normal" font="default" size="100%">Pakistan journal of biological sciences: PJBS</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Pak. J. Biol. Sci.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan 15</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">12</style></volume><pages><style face="normal" font="default" size="100%">192-4</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">This study was carried out in order to distinguish the effect of agroforestry system (combination of agriculture and forestry) on pests and natural enemy's population in poplar research station. Wood is one of the first substances that naturally was used for a long period of time. Forage is an important production of natural resources too. Some factors such as proper lands deficit, lack of economy, pest and disease attacks and faced production of these materials with serious challenges. Agroforestry is a method for decrease of the mentioned problems. The stands of poplar had have planted by complete randomized design with 4 treatments (stand distance) of poplar/alfalfa include 3x4, 3x6.7, 3x8, 3x10 m and 2 control treatments, alfalfa and poplar. The results showed that Chaitophorus populeti had the highest density in poplar and 3x10 m treatments. Monosteira unicostata is another insect pest that had most density in 3x10 m treatment. And alfalfa had high density of Chrysoperla carnea. The density of Coccinella septempunctata, were almost equal in all treatments.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19579945?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bhuiya, Mohammad-Wadud</style></author><author><style face="normal" font="default" size="100%">Liu, Chang-Jun</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A cost-effective colorimetric assay for phenolic O-methyltransferases and characterization of caffeate 3-O-methyltransferases from Populus trichocarpa.</style></title><secondary-title><style face="normal" font="default" size="100%">Analytical biochemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Anal. Biochem.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan 1</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">384</style></volume><pages><style face="normal" font="default" size="100%">151-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">S-adenosyl-L-methionine (AdoMet)-dependent O-methyltransferases (OMTs) catalyze the transmethylation of a variety of phenolics in bacteria, plants, and humans. To rapidly characterize phenolic OMT activities, we adapted Gibbs' reagent, the dye originally used for detecting phenols, to develop a convenient assay method for measuring the catalytic properties of enzymatic transmethylation of phenolics. We demonstrated that Gibbs' reagent reacted with phenolics yielding distinct absorptive characters that we used to further develop the assay to monitor the reactivities of phenolic OMTs. To validate the method, we identified two caffeate/5-hydroxyferulate 3/5-O-methyltransferases (COMTs) from the black cottonwood, Populus trichocarpa. Together with a few other plant type I OMTs, we demonstrated that our Gibbs' reagent-mediated colorimetric assay could reliably determine the functions and kinetic parameters of phenolic OMTs. Because Gibbs' reagent reacting with different regioselectively modified phenolics displays different colorimetric properties, the assay method can be used to monitor both substrate specificity and the regioselectivity of phenolic OMTs.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18926792?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Martin, Ludovic</style></author><author><style face="normal" font="default" size="100%">Leblanc-Fournier, Nathalie</style></author><author><style face="normal" font="default" size="100%">Azri, Wassim</style></author><author><style face="normal" font="default" size="100%">Lenne, Catherine</style></author><author><style face="normal" font="default" size="100%">Henry, Clémence</style></author><author><style face="normal" font="default" size="100%">Coutand, Catherine</style></author><author><style face="normal" font="default" size="100%">Julien, Jean-Louis</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Characterization and expression analysis under bending and other abiotic factors of PtaZFP2, a poplar gene encoding a Cys2/His2 zinc finger protein.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">125-36</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In plants, mechanoperception and transduction of mechanical signals have been studied essentially in Arabidopsis thaliana L. and Lycopersicon esculentum L. plants, i.e., in nonwoody plants. Here, we have described the isolation of both the full-length cDNA and the regulatory region of PtaZFP2, encoding a member of Cys2/His2 zinc finger protein (ZFP) family in Populus tremula L. x Populus alba L. Time course analysis of expression demonstrated that PtaZFP2 mRNA accumulated as early as 5 min in response to a controlled stem bending and is restricted to the organ where the mechanical stimulus is applied. The real-time quantitative Reverse Transcriptase Polymerase Chain Reaction experiments showed that PtaZFP2 was also rapidly up-regulated in poplar stems in response to gravitropism suggesting that PtaZFP2 is induced by different mechanical signals. Abundance of PtaZFP2 transcripts also increased highly in response to wounding and to a weaker extent to salt treatment and cold, which is consistent with the numerous putative cis-elements found in its regulatory region. As in other species, these data suggest that Cys2/His2 ZFPs could function in poplar as key transcriptional regulators in the acclimation response to different environmental factors.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19203938?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Decou, Raphael</style></author><author><style face="normal" font="default" size="100%">Lhernould, Sabine</style></author><author><style face="normal" font="default" size="100%">Laurans, Françoise</style></author><author><style face="normal" font="default" size="100%">Sulpice, Elodie</style></author><author><style face="normal" font="default" size="100%">Leplé, Jean-Charles</style></author><author><style face="normal" font="default" size="100%">Déjardin, Annabelle</style></author><author><style face="normal" font="default" size="100%">Pilate, Gilles</style></author><author><style face="normal" font="default" size="100%">Costa, Guy</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Cloning and expression analysis of a wood-associated xylosidase gene (PtaBXL1) in poplar tension wood.</style></title><secondary-title><style face="normal" font="default" size="100%">Phytochemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Phytochemistry</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">70</style></volume><pages><style face="normal" font="default" size="100%">163-72</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In stems of woody angiosperms responding to mechanical stress, imposed for instance by tilting the stem or formation of a branch, tension wood (TW) forms above the affected part, while anatomically distinct opposite wood (OW) forms below it. In poplar TW the S3 layer of the secondary walls is substituted by a &quot;gelatinous layer&quot; that is almost entirely composed of cellulose and has much lower hemicellulose contents than unstressed wood. However, changes in xylan contents (the predominant hemicelluloses), their interactions with other wall components and the mechanisms involved in TW formation have been little studied. Therefore, in the study reported here we determined the structure and distribution of xylans, cloned the genes encoding the xylan remodeling enzymes beta-xylosidases (PtaBXLi), and examined their expression patterns during tension wood, normal wood and opposite wood xylogenesis in poplar. We confirm that poplar wood xylans are substituted solely by 4-O-methylglucuronic acid in both TW and OW. However, although glucuronoxylans are strongly represented in both primary and secondary layers of OW, no 4-O-methylGlcA xylan was found in G-layers of TW. Four full-length BXL cDNAs encoding putative beta-xylosidases were cloned. One, PtaBXL1, for which xylosidase activity was confirmed by heterologous expression in Escherichia coli, exhibited a wood-specific expression pattern in TW. In conclusion, xylan as PtaBXL1, encoding beta4-xylosidase activity, are down-regulated in TW.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19162284?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kieffer, Pol</style></author><author><style face="normal" font="default" size="100%">Planchon, Sébastien</style></author><author><style face="normal" font="default" size="100%">Oufir, Mouhssin</style></author><author><style face="normal" font="default" size="100%">Ziebel, Johanna</style></author><author><style face="normal" font="default" size="100%">Dommes, Jacques</style></author><author><style face="normal" font="default" size="100%">Hoffmann, Lucien</style></author><author><style face="normal" font="default" size="100%">Hausman, Jean-François</style></author><author><style face="normal" font="default" size="100%">Renaut, Jenny</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Combining proteomics and metabolite analyses to unravel cadmium stress-response in poplar leaves.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of proteome research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Proteome Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">8</style></volume><pages><style face="normal" font="default" size="100%">400-17</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A proteomic analysis of poplar leaves exposed to cadmium, combined with biochemical analysis of pigments and carbohydrates revealed changes in primary carbon metabolism. Proteomic results suggested that photosynthesis was slightly affected. Together with a growth inhibition, photoassimilates were less needed for developmental processes and could be stored in the form of hexoses or complex sugars, acting also as osmoprotectants. Simultaneously, mitochondrial respiration was upregulated, providing energy needs of cadmium-exposed plants.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19072159?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ryan, A</style></author><author><style face="normal" font="default" size="100%">Cojocariu, C</style></author><author><style face="normal" font="default" size="100%">Possell, M</style></author><author><style face="normal" font="default" size="100%">Davies, W J</style></author><author><style face="normal" font="default" size="100%">Hewitt, C N</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Defining hybrid poplar (Populus deltoides x Populus trichocarpa) tolerance to ozone: identifying key parameters.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">32</style></volume><pages><style face="normal" font="default" size="100%">31-45</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">This study examined whether two genotypes of hybrid poplar (Populus deltoides x Populus trichocarpa), previously classified as ozone tolerant and ozone sensitive, had differing physiological and biochemical responses when fumigated with 120 nL L(-1) ozone for 6 h per day for eight consecutive days. Isoprene emission rate, ozone uptake and a number of physiological and biochemical parameters were investigated before, during and after fumigation with ozone. Previous studies have shown that isoprene protects plants against oxidative stress. Therefore, it was hypothesized that these two genotypes would differ in either their basal isoprene emission rates or in the response of isoprene to fumigation by ozone. Our results showed that the basal emission rates of isoprene, physiological responses and ozone uptake rates were all similar. However, significant differences were found in visible damage, carotenoids, hydrogen peroxide (H(2)O(2)), thiobarbituric acid reactions (TBARS) and post-fumigation isoprene emission rates. It is shown that, although the classification of ozone tolerance or sensitivity had been previously clearly and carefully defined using one particular set of parameters, assessment of other key variables does not necessarily lead to the same conclusions. Thus, it may be necessary to reconsider the way in which plants are classified as ozone tolerant or sensitive.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19076530?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Häikiö, Elina</style></author><author><style face="normal" font="default" size="100%">Freiwald, Vera</style></author><author><style face="normal" font="default" size="100%">Julkunen-Tiitto, Riitta</style></author><author><style face="normal" font="default" size="100%">Beuker, Egbert</style></author><author><style face="normal" font="default" size="100%">Holopainen, Toini</style></author><author><style face="normal" font="default" size="100%">Oksanen, Elina</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Differences in leaf characteristics between ozone-sensitive and ozone-tolerant hybrid aspen (Populus tremula x Populus tremuloides) clones.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">53-66</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The authors analyzed a suite of leaf characteristics that might help to explain the difference between ozone-sensitive and ozone-tolerant hybrid aspen (Populus tremula L. x Populus tremuloides Michx.) clones. An open-field experiment comprising ambient ozone and 1.5x ambient ozone concentration (about 35 ppb) and two soil nitrogen regimes (60 and 140 kg N ha(-1) year(-1)) was conducted over two growing seasons on potted plants of eight hybrid aspen clones. Four of the clones had previously been determined to be ozone sensitive based on impaired growth in response to elevated ozone concentration. Photosynthetic rate, chlorophyll fluorescence, and concentrations of chlorophyll, protein and carbohydrates were analyzed three times during the second growing season, and foliar phenolic concentrations were measured at the end of the second growing season. Nitrogen amendment counteracted the effects of ozone, but had no effect on growth-related ozone sensitivity of the clones. Ozone-sensitive clones had higher photosynthetic capacity and higher concentrations of Rubisco and phenolics than ozone-tolerant clones, but the effects of ozone were similar in the sensitive and tolerant groups. Nitrogen addition had no effect on phenolic concentration, but elevated ozone concentration increased the concentrations of chlorogenic acid and (+)-catechin. This study suggests that condensed tannins and catechin, but not salicylates or flavonol glycosides, play a role in the ozone tolerance of hybrid aspen.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19203932?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kreuzwieser, Jürgen</style></author><author><style face="normal" font="default" size="100%">Hauberg, Jost</style></author><author><style face="normal" font="default" size="100%">Howell, Katharine A</style></author><author><style face="normal" font="default" size="100%">Carroll, Adam</style></author><author><style face="normal" font="default" size="100%">Rennenberg, Heinz</style></author><author><style face="normal" font="default" size="100%">Millar, A Harvey</style></author><author><style face="normal" font="default" size="100%">Whelan, James</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Differential response of gray poplar leaves and roots underpins stress adaptation during hypoxia.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">149</style></volume><pages><style face="normal" font="default" size="100%">461-73</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The molecular and physiological responses of gray poplar (Populus x canescens) following root hypoxia were studied in roots and leaves using transcript and metabolite profiling. The results indicate that there were changes in metabolite levels in both organs, but changes in transcript abundance were restricted to the roots. In roots, starch and sucrose degradation were altered under hypoxia, and concurrently, the availability of carbohydrates was enhanced, concomitant with depletion of sucrose from leaves and elevation of sucrose in the phloem. Consistent with the above, glycolytic flux and ethanolic fermentation were stimulated in roots but not in leaves. Various messenger RNAs encoding components of biosynthetic pathways such as secondary cell wall formation (i.e. cellulose and lignin biosynthesis) and other energy-demanding processes such as transport of nutrients were significantly down-regulated in roots but not in leaves. The reduction of biosynthesis was unexpected, as shoot growth was not affected by root hypoxia, suggesting that the up-regulation of glycolysis yields sufficient energy to maintain growth. Besides carbon metabolism, nitrogen metabolism was severely affected in roots, as seen from numerous changes in the transcriptome and the metabolome related to nitrogen uptake, nitrogen assimilation, and amino acid metabolism. The coordinated physiological and molecular responses in leaves and roots, coupled with the transport of metabolites, reveal important stress adaptations to ensure survival during long periods of root hypoxia.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19005089?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Slavov, G T</style></author><author><style face="normal" font="default" size="100%">Leonardi, S</style></author><author><style face="normal" font="default" size="100%">Burczyk, J</style></author><author><style face="normal" font="default" size="100%">Adams, W T</style></author><author><style face="normal" font="default" size="100%">Strauss, S H</style></author><author><style face="normal" font="default" size="100%">DiFazio, S P</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Extensive pollen flow in two ecologically contrasting populations of Populus trichocarpa.</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Ecol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">18</style></volume><pages><style face="normal" font="default" size="100%">357-73</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Pollen-mediated gene flow was measured in two populations of black cottonwood using direct (paternity analysis) and indirect (correlated paternity) methods. The Marchel site was an area with an approximate radius of 250 m in a large continuous stand growing in a mesic habitat in western Oregon. In contrast, the Vinson site was an area with a radius of approximately 10 km and consisted of small, disjunct and isolated stands in the high desert of eastern Oregon. Pollen immigration was extensive in both populations, and was higher in the Marchel site (0.54 +/- 0.02) than in the substantially larger and more isolated Vinson site (0.32 +/- 0.02). Pollen pool differentiation among mothers was approximately five times stronger in the Vinson population (Phi FT = 0.253, N = 27 mothers) than in the Marchel population (Phi FT = 0.052, N = 5 mothers). Pollen dispersal was modelled using a mixed dispersal curve that incorporated pollen immigration. Predicted pollination frequencies generated based on this curve were substantially more accurate than those based on the widely used exponential power dispersal curve. Male neighbourhood sizes (sensu Wright 1946) estimated using paternity analysis and pollen pool differentiation were remarkably similar. They were three to five times smaller in the Vinson population, which reflected the substantial ecological and demographic differences between the two populations. When the same mathematical function was used, applying direct and indirect methods resulted in similar pollen dispersal curves, thus confirming the value of indirect methods as a viable lower-cost alternative to paternity analysis.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19076277?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lu, Hai</style></author><author><style face="normal" font="default" size="100%">Han, Rui-Li</style></author><author><style face="normal" font="default" size="100%">Jiang, Xiang-Ning</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Heterologous expression and characterization of a proxidomal ascorbate peroxidase from Populus tomentosa.</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular biology reports</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Biol. Rep.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">36</style></volume><pages><style face="normal" font="default" size="100%">21-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The present study reported for the first time, cloning, expression and characteristics of a Proxidomal APX gene (PpAPX) from Populus tomentosa. The PpAPX gene encodes a protein of 287 amino acid residues with a calculated molecular mass of 31.58 kDa. The over-expressed recombinant PpAPX protein showed high activity towards the substrates ascorbate aicd (ASA) and H(2)O(2). At fixed ASA concentrations, the K (m) and V (max) values were 0.12 +/- 0.01 mM and 23.4 +/- 4.2 mmol/min mg for H(2)O(2). And at fixed H(2)O(2) concentrations, the K (m) and V (max) values were 0.53 +/- 0.04 mM and 20.0 +/- 2.3 mmol/min mg for ASA.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17899442?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bylesjö, Max</style></author><author><style face="normal" font="default" size="100%">Nilsson, Robert</style></author><author><style face="normal" font="default" size="100%">Srivastava, Vaibhav</style></author><author><style face="normal" font="default" size="100%">Grönlund, Andreas</style></author><author><style face="normal" font="default" size="100%">Johansson, Annika I</style></author><author><style face="normal" font="default" size="100%">Jansson, Steffan</style></author><author><style face="normal" font="default" size="100%">Karlsson, Jan</style></author><author><style face="normal" font="default" size="100%">Moritz, Thomas</style></author><author><style face="normal" font="default" size="100%">Wingsle, Gunnar</style></author><author><style face="normal" font="default" size="100%">Trygg, Johan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Integrated analysis of transcript, protein and metabolite data to study lignin biosynthesis in hybrid aspen.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of proteome research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Proteome Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">8</style></volume><pages><style face="normal" font="default" size="100%">199-210</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Tree biotechnology will soon reach a mature state where it will influence the overall supply of fiber, energy and wood products. We are now ready to make the transition from identifying candidate genes, controlling important biological processes, to discovering the detailed molecular function of these genes on a broader, more holistic, systems biology level. In this paper, a strategy is outlined for informative data generation and integrated modeling of systematic changes in transcript, protein and metabolite profiles measured from hybrid aspen samples. The aim is to study characteristics of common changes in relation to genotype-specific perturbations affecting the lignin biosynthesis and growth. We show that a considerable part of the systematic effects in the system can be tracked across all platforms and that the approach has a high potential value in functional characterization of candidate genes.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19053836?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Yin, T M</style></author><author><style face="normal" font="default" size="100%">Zhang, X Y</style></author><author><style face="normal" font="default" size="100%">Gunter, L E</style></author><author><style face="normal" font="default" size="100%">Li, S X</style></author><author><style face="normal" font="default" size="100%">Wullschleger, S D</style></author><author><style face="normal" font="default" size="100%">Huang, M R</style></author><author><style face="normal" font="default" size="100%">Tuskan, G A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Microsatellite primer resource for Populus developed from the mapped sequence scaffolds of the Nisqually-1 genome.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">181</style></volume><pages><style face="normal" font="default" size="100%">498-503</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In this study, 148 428 simple sequence repeat (SSR) primer pairs were designed from the unambiguously mapped sequence scaffolds of the Nisqually-1 genome. The physical position of the priming sites were identified along each of the 19 Populus chromosomes, and it was specified whether the priming sequences belong to intronic, intergenic, exonic or UTR regions. A subset of 150 SSR loci were amplified and a high amplification success rate (72%) was obtained in P. tremuloides, which belongs to a divergent subgenus of Populus relative to Nisqually-1. PCR reactions showed that the amplification success rate of exonic primer pairs was much higher than that of the intronic/intergenic primer pairs. Applying ANOVA and regression analyses to the flanking sequences of microsatellites, the repeat lengths, the GC contents of the repeats, the repeat motif numbers, the repeat motif length and the base composition of the repeat motif, it was determined that only the base composition of the repeat motif and the repeat motif length significantly affect the microsatellite variability in P. tremuloides samples. The SSR primer resource developed in this study provides a database for selecting highly transferable SSR markers with known physical position in the Populus genome and provides a comprehensive genetic tool to extend the genome sequence of Nisqually-1 to genetic studies in different Populus species.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19121044?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Grönlund, Andreas</style></author><author><style face="normal" font="default" size="100%">Bhalerao, Rishikesh P</style></author><author><style face="normal" font="default" size="100%">Karlsson, Jan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Modular gene expression in Poplar: a multilayer network approach.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">181</style></volume><pages><style face="normal" font="default" size="100%">315-22</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">By applying a multilayer network approach to an extensive set of Poplar microarray data, a genome-wide coexpression network has been detected and explored. Multilayer networks were generated from minimum spanning trees (MSTs) using Kruskal's algorithm from random jack-knife resamplings of half of the full data set. The final network is obtained from the union of all the generated MSTs. The gene expression correlations display a highly clustered topology, which is more pronounced when introducing links appearing in relatively few of the generated MSTs. The network also reveals a modular architecture, reflecting functional groups with relatively frequent gene-to-gene communication. Furthermore, the observed modular structure overlaps with different gene activities in different tissues, and closely related tissues show similar over- and/or under-expression patterns at the modular scale. It is shown that including links that appear in a few of the generated MSTs increases the information quality of the network. In other words, a link may be 'weak' because it reflects rare signaling events rather than merely a signal weakened by noise. The method allows, from comparisons of random 'null networks', tuning to maximize the information obtainable.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19121030?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Marzuoli, Riccardo</style></author><author><style face="normal" font="default" size="100%">Gerosa, Giacomo</style></author><author><style face="normal" font="default" size="100%">Desotgiu, Rosanna</style></author><author><style face="normal" font="default" size="100%">Bussotti, Filippo</style></author><author><style face="normal" font="default" size="100%">Ballarin-Denti, Antonio</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Ozone fluxes and foliar injury development in the ozone-sensitive poplar clone Oxford (Populus maximowiczii x Populus berolinensis): a dose-response analysis.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">67-76</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Between 2004 and 2005 a combined open plot and open-top chamber (OTC) experiment was carried out at Curno (Northern Italy) with cuttings of the poplar clone Oxford (Populus maximowiczii Henry x Populus berolinensis Dippel) grown in open plots (OPs, ambient air), charcoal-filtered OTCs (CF, ozone concentration reduced to 50% of ambient) or non-filtered OTCs (NF, ozone concentration reduced to 95% of ambient). Plants in half of the chambers were kept well-watered (WET), and plants in the remaining chambers were not watered (DRY). The onset and development of visible foliar injury and the stomatal conductance to water vapor (g(w)) were assessed during each growing season. A stomatal conductance model was parameterized by the Jarvis approach, allowing the calculation of ozone stomatal fluxes of plants in each treatment. The pattern of visible symptoms was analyzed in relation to ozone exposure (AOT40, accumulated ozone over a threshold of 40 ppb) and accumulated ozone stomatal fluxes (AF(ST)). Symptoms became visible at an AOT40 between 9584 and 13,110 ppb h and an AF(ST) between 27.85 and 30.40 mmol O(3) m(-2). The development of symptoms was more widespread and faster in plants in WET plots than in DRY plots. A slightly higher dose of ozone was required to cause visible symptoms in plants in DRY plots than in WET plots. By the end of each growing season, plants in the CF OTCs had absorbed a high dose of ozone (31.60 mmol O(3) m(-2) in 2004 and 32.83 mmol O(3) m(-2) in 2005, for WET plots), without developing any visible symptoms. A reliable dose-response relationship was defined by a sigmoidal curve model. The shape of this curve expresses the change in leaf sensitivity and physiologic state over a prolonged ozone exposure. After the appearance of the first symptoms, foliar injury increased more rapidly than the increases in ozone exposure and ozone absorbed dose; however, when the injury incidence reached 75%, the plant response declined.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19203933?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Chen, Shaoliang</style></author><author><style face="normal" font="default" size="100%">Olbrich, Andrea</style></author><author><style face="normal" font="default" size="100%">Langenfeld-Heyser, Rosemarie</style></author><author><style face="normal" font="default" size="100%">Fritz, Eberhard</style></author><author><style face="normal" font="default" size="100%">Polle, Andrea</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Quantitative X-ray microanalysis of hydrogen peroxide within plant cells.</style></title><secondary-title><style face="normal" font="default" size="100%">Microscopy research and technique</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Microsc. Res. Tech.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">72</style></volume><pages><style face="normal" font="default" size="100%">49-60</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Using quantitative X-ray microanalysis in combination with CeCl3-based cytochemical staining of hydrogen peroxide (H2O2) we have developed a new solution for quantification of H2O2 at the subcellular level. Quantitative X-ray microanalysis of plastic-embedded leaves of Populus euphratica Oliv. showed that the obtained cerium precipitates by CeCl3 staining were the mixture of cerium perhydroxides and cerium phosphate, in which the fractions of CePO4 were: (1) 52-74% in cell walls of fresh leaf segments, and (2) 34-70% in the cytoplasm in 10 mM H2O2-treated leaf segments that were previously freeze-dried. Taking the concentration of cerium phosphate as staining background, we reached the cellular concentration of cerium perhydroxides and the corresponding concentration of H2O2. Results showed that H2O2 was present in the cytoplasm of rehydrated leaf segments (29-58 mM), but in fresh leaves, H2O2 was observed in the walls of all measured cell types (17-74 mM).</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18837436?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Escalante-Pérez, María</style></author><author><style face="normal" font="default" size="100%">Lautner, Silke</style></author><author><style face="normal" font="default" size="100%">Nehls, Uwe</style></author><author><style face="normal" font="default" size="100%">Selle, Anita</style></author><author><style face="normal" font="default" size="100%">Teuber, Markus</style></author><author><style face="normal" font="default" size="100%">Schnitzler, Jörg-Peter</style></author><author><style face="normal" font="default" size="100%">Teichmann, Thomas</style></author><author><style face="normal" font="default" size="100%">Fayyaz, Payam</style></author><author><style face="normal" font="default" size="100%">Hartung, Wolfram</style></author><author><style face="normal" font="default" size="100%">Polle, Andrea</style></author><author><style face="normal" font="default" size="100%">Fromm, Jörg</style></author><author><style face="normal" font="default" size="100%">Hedrich, Rainer</style></author><author><style face="normal" font="default" size="100%">Ache, Peter</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Salt stress affects xylem differentiation of grey poplar (Populus x canescens).</style></title><secondary-title><style face="normal" font="default" size="100%">Planta</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Planta</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">229</style></volume><pages><style face="normal" font="default" size="100%">299-309</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In this study the impact of salt stress on the physiology and wood structure of the salt-sensitive Populus x canescens was investigated. Two weeks of salt stress altered wood anatomy significantly. The xylem differentiation zone was reduced and the resulting vessels exhibited reduced lumina. To understand this phenomenon, ion composition, levels of corresponding transcripts and of the stress hormone ABA were analysed. With increasing sodium and chloride concentrations, a general reduction of potassium was found in roots and shoots, but not in leaves. Consequently, the corresponding K+ channel transcripts in roots favoured K+ release. The overall osmolarity in leaves was up to fourfold higher than in roots or shoots. Therefore, adjustment of the K+/Na+ balance seemed not to be required in leaves. Sodium increased gradually from roots to shoots and then to leaves indicating that sodium storage took place first in roots, then in shoots, and finally in leaves to protect photosynthesis from salt effects as long as possible. Since leaf abscisic acid levels markedly increased, stomatal closure seemed to limit CO2 uptake. As a consequence, diminished nutrient supply to the cambium in combination with lowered shoot K+ content led to decreased vessel lumina, and a reduction of the radial cambium was observed. Thus, xylem differentiation was curtailed and the development of full size vessels was impaired.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18946679?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhao, Nan</style></author><author><style face="normal" font="default" size="100%">Guan, Ju</style></author><author><style face="normal" font="default" size="100%">Forouhar, Farhad</style></author><author><style face="normal" font="default" size="100%">Tschaplinski, Timothy J</style></author><author><style face="normal" font="default" size="100%">Cheng, Zong-Ming</style></author><author><style face="normal" font="default" size="100%">Tong, Liang</style></author><author><style face="normal" font="default" size="100%">Chen, Feng</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Two poplar methyl salicylate esterases display comparable biochemical properties but divergent expression patterns.</style></title><secondary-title><style face="normal" font="default" size="100%">Phytochemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Phytochemistry</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">70</style></volume><pages><style face="normal" font="default" size="100%">32-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Two genes encoding proteins of 98% sequence identity that are highly homologous to tobacco methyl salicylate (MeSA) esterase (SABP2) were identified and cloned from poplar. Proteins encoded by these two genes displayed specific esterase activities towards MeSA to produce salicylic acid, and are named PtSABP2-1 and PtSABP2-2, respectively. Recombinant PtSABP2-1 and PtSABP2-2 exhibited apparent Km values of 68.2+/-3.8microM and 24.6+/-1microM with MeSA, respectively. Structural modeling using the three-dimensional structure of tobacco SABP2 as a template indicated that the active sites of PtSABP2-1 and PtSABP2-2 were highly similar to that of tobacco SABP2. Under normal growing conditions, PtSABP2-1 showed the highest level of expression in leaves and PtSABP2-2 was most highly expressed in roots. In leaf tissues of poplar plants under stress conditions, the expression of PtSABP2-1 was significantly down-regulated by two stress factors, whereas the expression of PtSABP2-2 was significantly up-regulated by four stress factors. The plausible mechanisms leading to these two highly homologous MeSA esterase genes involved in divergent biological processes in poplar are discussed.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19136124?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wilkins, Olivia</style></author><author><style face="normal" font="default" size="100%">Nahal, Hardeep</style></author><author><style face="normal" font="default" size="100%">Foong, Justin</style></author><author><style face="normal" font="default" size="100%">Provart, Nicholas J</style></author><author><style face="normal" font="default" size="100%">Campbell, Malcolm M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Expansion and diversification of the Populus R2R3-MYB family of transcription factors.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">149</style></volume><pages><style face="normal" font="default" size="100%">981-93</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The R2R3-MYB proteins comprise one of the largest families of transcription factors in plants. R2R3-MYB family members regulate plant-specific processes, such as the elaboration of specialized cell types, including xylem, guard cells, trichomes, and root hairs, and the biosynthesis of specialized branches of metabolism, including phenylpropanoid biosynthesis. As such, R2R3-MYB family members are hypothesized to contribute to the emergence of evolutionary innovations that have arisen in specific plant lineages. As a first step in determining the role played by R2R3-MYB family members in the emergence of lineage-specific innovations in the genus Populus, the entire Populus trichocarpa R2R3-MYB family was characterized. The Populus R2R3-MYB complement is much larger than that found in other angiosperms with fully sequenced genomes. Phylogenetic analyses, together with chromosome placement, showed that the expansion of the Populus R2R3-MYB family was not only attributable to whole genome duplication but also involved selective expansion of specific R2R3-MYB clades. Expansion of the Populus R2R3-MYB family prominently involved members with expression patterns that suggested a role in specific components of Populus life history, including wood formation and reproductive development. An expandable compendium of microarray-based expression data (PopGenExpress) and associated Web-based tools were developed to better enable within- and between-species comparisons of Populus R2R3-MYB gene expression. This resource, which includes intuitive graphic visualization of gene expression data across multiple tissues, organs, and treatments, is freely available to, and expandable by, scientists wishing to better understand the genome biology of Populus, an ecologically dominant and economically important forest tree genus.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19091872?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Li, Yiliang</style></author><author><style face="normal" font="default" size="100%">Su, Xiaohua</style></author><author><style face="normal" font="default" size="100%">Zhang, Bingyu</style></author><author><style face="normal" font="default" size="100%">Huang, Qinjun</style></author><author><style face="normal" font="default" size="100%">Zhang, Xianghua</style></author><author><style face="normal" font="default" size="100%">Huang, Rongfeng</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Expression of jasmonic ethylene responsive factor gene in transgenic poplar tree leads to increased salt tolerance.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">273-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The stress resistance of plants can be enhanced by regulating the expression of multiple downstream genes associated with stress resistance. We used the Agrobacterium method to transfer the tomato jasmonic ethylene responsive factors (JERFs) gene that encodes the ethylene response factor (ERF) like transcription factor to the genome of a hybrid poplar (Populus alba x Populus berolinensis). Eighteen resistant plants were obtained, of which 13 were identified by polymerase chain reaction (PCR), reverse transcriptase PCR and Southern blot analyses as having incorporated the JERFs gene and able to express it at the transcriptional level. Salinity tests were conducted in a greenhouse with 0, 100, 200 and 300 mM NaCl. In the absence of NaCl, the transgenic plants were significantly taller than the control plants, but no statistically significant differences in the concentrations of proline and chlorophyll were observed. With increasing salinity, the extent of damage was significantly less in transgenic plants than that in control plants, and the reductions in height, basal diameter and biomass were less in transgenic plants than those in control plants. At 200 and 300 mM NaCl concentrations, transgenic plants were 128.9% and 98.8% taller, respectively, and had 199.8% and 113.0% more dry biomass, respectively, than control plants. The saline-induced reduction in leaf water content and increase in root/crown ratio were less in transgenic plants than in control plants. Foliar proline concentration increased more in response to salt treatment in transgenic plants than in control plants. Foliar Na(+) concentration was higher in transgenic plants than in control plants. In the coastal area in Panjin of Liaoning where the total soil salt concentration is 0.3%, a salt tolerance trial of transgenic plants indicated that 3-year-old transgenic plants were 14.5% and 33.6% taller than the control plants at two field sites. The transgenic plants at the two field sites were growing vigorously, had dark green leaves and showed no symptoms of salt damage, implying that the JERFs gene enhanced their salt tolerance.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19203952?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Taghavi, Safiyh</style></author><author><style face="normal" font="default" size="100%">Garafola, Craig</style></author><author><style face="normal" font="default" size="100%">Monchy, Sébastien</style></author><author><style face="normal" font="default" size="100%">Newman, Lee</style></author><author><style face="normal" font="default" size="100%">Hoffman, Adam</style></author><author><style face="normal" font="default" size="100%">Weyens, Nele</style></author><author><style face="normal" font="default" size="100%">Barac, Tanja</style></author><author><style face="normal" font="default" size="100%">Vangronsveld, Jaco</style></author><author><style face="normal" font="default" size="100%">van der Lelie, Daniel</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genome survey and characterization of endophytic bacteria exhibiting a beneficial effect on growth and development of poplar trees.</style></title><secondary-title><style face="normal" font="default" size="100%">Applied and environmental microbiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Appl. Environ. Microbiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">75</style></volume><pages><style face="normal" font="default" size="100%">748-57</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The association of endophytic bacteria with their plant hosts has a beneficial effect for many different plant species. Our goal is to identify endophytic bacteria that improve the biomass production and the carbon sequestration potential of poplar trees (Populus spp.) when grown in marginal soil and to gain an insight in the mechanisms underlying plant growth promotion. Members of the Gammaproteobacteria dominated a collection of 78 bacterial endophytes isolated from poplar and willow trees. As representatives for the dominant genera of endophytic gammaproteobacteria, we selected Enterobacter sp. strain 638, Stenotrophomonas maltophilia R551-3, Pseudomonas putida W619, and Serratia proteamaculans 568 for genome sequencing and analysis of their plant growth-promoting effects, including root development. Derivatives of these endophytes, labeled with gfp, were also used to study the colonization of their poplar hosts. In greenhouse studies, poplar cuttings (Populus deltoides x Populus nigra DN-34) inoculated with Enterobacter sp. strain 638 repeatedly showed the highest increase in biomass production compared to cuttings of noninoculated control plants. Sequence data combined with the analysis of their metabolic properties resulted in the identification of many putative mechanisms, including carbon source utilization, that help these endophytes to thrive within a plant environment and to potentially affect the growth and development of their plant hosts. Understanding the interactions between endophytic bacteria and their host plants should ultimately result in the design of strategies for improved poplar biomass production on marginal soils as a feedstock for biofuels.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19060168?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Birch, Hayley</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">GM poplars to grow next door.</style></title><secondary-title><style face="normal" font="default" size="100%">Nature biotechnology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Nat. Biotechnol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">27</style></volume><pages><style face="normal" font="default" size="100%">107</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19204672?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Nakamura, Michimi</style></author><author><style face="normal" font="default" size="100%">Kuramata, Masato</style></author><author><style face="normal" font="default" size="100%">Kasugai, Isao</style></author><author><style face="normal" font="default" size="100%">Abe, Midori</style></author><author><style face="normal" font="default" size="100%">Youssefian, Shohab</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Increased thiol biosynthesis of transgenic poplar expressing a wheat O-acetylserine(thiol) lyase enhances resistance to hydrogen sulfide and sulfur dioxide toxicity.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant cell reports</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Rep.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">313-23</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">O-acetylserine(thiol) lyase (OASTL), a key enzyme of the plant sulfur assimilatory pathway, catalyses the formation of cysteine from sulfide and O-acetylserine. Transgenic hybrid poplar (Populus sieboldi x P. grandidentata 'Y63') plants expressing cys1, encoding a wheat cytosolic OASTL, were developed in order to examine the role of this enzyme in thiol production following hydrogen sulfide or sulfur dioxide exposure and in the extent of damage induced in the plants by these pollutants. The transgenic cys1 plants accumulated up to several-fold higher cysteine and glutathione levels and were significantly more resistant in terms of foliar damage to the pollutants than WT plants. The transgenic poplar also showed higher tolerance to sulfite and hydrogen peroxide and, interestingly, accumulated several-fold higher sulfite reductase transcripts than WT plants in response to sulfur dioxide. These data clearly demonstrate the important role of OASTL and the sulfur reduction pathway in sulfur and oxidative stress amelioration, and support the notion that transgenic trees resistant to such pollutants can be generated for phytoremediation strategies.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19011861?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bose, Samar K</style></author><author><style face="normal" font="default" size="100%">Francis, Raymond C</style></author><author><style face="normal" font="default" size="100%">Govender, Mark</style></author><author><style face="normal" font="default" size="100%">Bush, Tamara</style></author><author><style face="normal" font="default" size="100%">Spark, Andrew</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Lignin content versus syringyl to guaiacyl ratio amongst poplars.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioresource technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bioresour. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">100</style></volume><pages><style face="normal" font="default" size="100%">1628-33</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Two oxidation techniques that afford high yields of monomers and dimers were used to more accurately estimate the syringyl to guaiacyl (S:G) ratio of hardwood lignins. Permanganate oxidation of the woodmeal after a CuO pre-hydrolysis step gave poor results and this was attributed to preferential oxidation and degradation of syringyl nuclei by CuO. However, this procedure did provide a good estimate of the percentages of both S and G phenylpropane (C(9)) units that were uncondensed. When the total S and G products from nitrobenzene oxidation (NBO) of the uncondensed fractions were corrected, credible S:G ratios were obtained. These ratios were in good agreement with results from KMnO4 oxidation of dissolved kraft lignin without CuO pre-hydrolysis. The corrected NBO method was used to determine the S:G ratio of 13 poplars, and the values ranged from 1.01 to 1.68. Unlike results from other investigations, an excellent linear correlation (R(2) =0.846) was obtained for a decreasing lignin content (28% to 16.5%) with an increase in the S:G ratio.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18954979?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sun, Jian</style></author><author><style face="normal" font="default" size="100%">Chen, Shaoliang</style></author><author><style face="normal" font="default" size="100%">Dai, Songxiang</style></author><author><style face="normal" font="default" size="100%">Wang, Ruigang</style></author><author><style face="normal" font="default" size="100%">Li, Niya</style></author><author><style face="normal" font="default" size="100%">Shen, Xin</style></author><author><style face="normal" font="default" size="100%">Zhou, Xiaoyang</style></author><author><style face="normal" font="default" size="100%">Lu, Cunfu</style></author><author><style face="normal" font="default" size="100%">Zheng, Xiaojiang</style></author><author><style face="normal" font="default" size="100%">Hu, Zanmin</style></author><author><style face="normal" font="default" size="100%">Zhang, Zengkai</style></author><author><style face="normal" font="default" size="100%">Song, Jin</style></author><author><style face="normal" font="default" size="100%">Xu, Yue</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">NaCl-induced alternations of cellular and tissue ion fluxes in roots of salt-resistant and salt-sensitive poplar species.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">149</style></volume><pages><style face="normal" font="default" size="100%">1141-53</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Using the scanning ion-selective electrode technique, fluxes of H+, Na+, and Cl- were investigated in roots and derived protoplasts of salt-tolerant Populus euphratica and salt-sensitive Populus popularis 35-44 (P. popularis). Compared to P. popularis, P. euphratica roots exhibited a higher capacity to extrude Na+ after a short-term exposure to 50 mM NaCl (24 h) and a long term in a saline environment of 100 mM NaCl (15 d). Root protoplasts, isolated from the long-term-stressed P. euphratica roots, had an enhanced Na+ efflux and a correspondingly increased H+ influx, especially at an acidic pH of 5.5. However, the NaCl-induced Na+/H+ exchange in root tissues and cells was inhibited by amiloride (a Na+/H+ antiporter inhibitor) or sodium orthovanadate (a plasma membrane H+-ATPase inhibitor). These results indicate that the Na+ extrusion in stressed P. euphratica roots is the result of an active Na+/H+ antiport across the plasma membrane. In comparison, the Na+/H+ antiport system in salt-stressed P. popularis roots was insufficient to exclude Na+ at both the tissue and cellular levels. Moreover, salt-treated P. euphratica roots retained a higher capacity for Cl- exclusion than P. popularis, especially during a long term in high salinity. The pattern of NaCl-induced fluxes of H+, Na+, and Cl- differs from that caused by isomotic mannitol in P. euphratica roots, suggesting that NaCl-induced alternations of root ion fluxes are mainly the result of ion-specific effects.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19028881?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Li, Jingyi</style></author><author><style face="normal" font="default" size="100%">Brunner, Amy M</style></author><author><style face="normal" font="default" size="100%">Meilan, Richard</style></author><author><style face="normal" font="default" size="100%">Strauss, Steven H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Stability of transgenes in trees: expression of two reporter genes in poplar over three field seasons.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">299-312</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">High stability of transgene expression is essential for functional genomics studies using transformation approaches and for application of genetic engineering to commercial forestry. We quantified expression of two reporter genes, green fluorescent protein (GFP) and the herbicide bialaphos resistance gene (BAR), in 2256 transgenic poplar trees derived from 404 primary events, and in 106 in vitro-redifferentiated subevents, over 3 years in the greenhouse and in the field. No gene silencing (complete breakdown of expression) was observed for GFP or BAR expression in any of the primary transgenic events during the course of the study. Transgenic cassettes were physically eliminated in four subevents (2.5%) derived from three different primary events during re-organogenesis. Transgene copy number was positively correlated with transgene expression level; however, a majority of transformants (85%) carried single-copy transgenes. About one-third of the events containing two-copy inserts had repeats formed at the same chromosomal position, with direct repeats being the main type observed (87%). All events containing more than two transgene copies showed repeat formation at least at one locus, with direct repeats again dominant (77%). Loci with two direct repeats had substantially greater transgene expression level than other types of two-copy T-DNA configurations, but insert organization was not associated with stability of transgene expression. Use of the poplar rbcS promoter, which drove BAR in the transgenic constructs, had no adverse effect on transgene expression levels or stability compared with the heterologous CaMV 35S promoter, which directed GFP expression.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19203955?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Galvagno, S</style></author><author><style face="normal" font="default" size="100%">Casciaro, G</style></author><author><style face="normal" font="default" size="100%">Casu, S</style></author><author><style face="normal" font="default" size="100%">Martino, M</style></author><author><style face="normal" font="default" size="100%">Mingazzini, C</style></author><author><style face="normal" font="default" size="100%">Russo, A</style></author><author><style face="normal" font="default" size="100%">Portofino, S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Steam gasification of tyre waste, poplar, and refuse-derived fuel: a comparative analysis.</style></title><secondary-title><style face="normal" font="default" size="100%">Waste management (New York, N.Y.)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Waste Manag</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">678-89</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In the field of waste management, thermal disposal is a treatment option able to recover resources from &quot;end of life&quot; products. Pyrolysis and gasification are emerging thermal treatments that work under less drastic conditions in comparison with classic direct combustion, providing for reduced gaseous emissions of heavy metals. Moreover, they allow better recovery efficiency since the process by-products can be used as fuels (gas, oils), for both conventional (classic engines and heaters) and high efficiency apparatus (gas turbines and fuel cells), or alternatively as chemical sources or as raw materials for other processes. This paper presents a comparative study of a steam gasification process applied to three different waste types (refuse-derived fuel, poplar wood and scrap tyres), with the aim of comparing the corresponding yields and product compositions and exploring the most valuable uses of the by-products.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18657408?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Azaiez, Aïda</style></author><author><style face="normal" font="default" size="100%">Boyle, Brian</style></author><author><style face="normal" font="default" size="100%">Levée, Valérie</style></author><author><style face="normal" font="default" size="100%">Séguin, Armand</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Transcriptome profiling in hybrid poplar following interactions with Melampsora rust fungi.</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular plant-microbe interactions : MPMI</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Plant Microbe Interact.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">22</style></volume><pages><style face="normal" font="default" size="100%">190-200</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In natural conditions, plants are subjected to a combination of biotic stresses and often have to cope with simultaneous pathogen infections. In this report, we aim to understand the global transcriptional response of hybrid poplar NM6 (Populus nigra x P. maximowiczii) to infection by two biotrophic Melampsora fungi, Melampsora larici-populina and M. medusae f. sp. deltoidae. These pathogens triggered different responses after inoculation of poplar leaves. Transcript profiling using the GeneChip Poplar Genome Array revealed a total of 416 differentially expressed transcripts whose expression level was &gt; or = twofold relative to controls. Interestingly, approximately half of the differentially expressed genes in infected leaves showed altered expression following interaction with either of the Melampsora spp. We also infected poplar leaves simultaneously with both Melampsora spp. to investigate potential interaction between the responses to the individual pathogens during a mixed infection. For this mixed inoculation, the number of differentially expressed transcripts increased to 648 and our analysis showed that infection with both fungi also induced a common set of genes. The genes induced after Melampsora spp. infection were mainly related to primary and secondary metabolic processes, cell-wall reinforcement and lignification, defense and stress-related mechanisms, and signal perception and transduction.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19132871?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Govender, Mark</style></author><author><style face="normal" font="default" size="100%">Bush, Tamara</style></author><author><style face="normal" font="default" size="100%">Spark, Andrew</style></author><author><style face="normal" font="default" size="100%">Bose, Samar K</style></author><author><style face="normal" font="default" size="100%">Francis, Raymond C</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">An accurate and non-labor intensive method for the determination of syringyl to guaiacyl ratio in lignin.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioresource technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bioresour. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">100</style></volume><pages><style face="normal" font="default" size="100%">5834-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The syringyl to guaiacyl (S:G) ratio of hardwood lignin has long been identified as a significant parameter in delignification processes and more recent results have shown that it is also important in determining the amount of ethanol that can be obtained from fermentation of hydrolyzed wood. Acidolysis of Klason or acid insoluble lignin in dioxane/water/HCl was being investigated when syringyl and guaiacyl nuclei with a diketone-containing sidechain were observed as the major products. The area ratio of the two gas chromatogram peaks appeared to be indicative of the S:G ratio. After optimization of the method the relative standard deviation was found to be in the range of 0.3-3.76% for Klason lignin from a wide range of Eucalyptus grandis grown in South Africa. The method was then compared to nitrobenzene oxidation (NBO) using 13 poplars in a double-blind study. The respective S:G ratios were used to calculate percentages of S units and when these values were plotted against each other a linear correlation was obtained with a slope of approximately 1.0 (R(2)=0.86). The largest discrepancy for any poplar was 6.9% (62% vs. 58% S units). Both methods convincingly demonstrated a significant decrease in lignin content with an increase in the S:G ratio. Discussion is presented on a series of reaction that could lead to the formation of the two diketones.</style></abstract><issue><style face="normal" font="default" size="100%">23</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19576762?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Regier, Nicole</style></author><author><style face="normal" font="default" size="100%">Streb, Sebastian</style></author><author><style face="normal" font="default" size="100%">Cocozza, Claudia</style></author><author><style face="normal" font="default" size="100%">Schaub, Marcus</style></author><author><style face="normal" font="default" size="100%">Cherubini, Paolo</style></author><author><style face="normal" font="default" size="100%">Zeeman, Samuel C</style></author><author><style face="normal" font="default" size="100%">Frey, Beat</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Drought tolerance of two black poplar (Populus nigra L.) clones: contribution of carbohydrates and oxidative stress defence.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">32</style></volume><pages><style face="normal" font="default" size="100%">1724-36</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Drought is expected to become an increasingly important factor limiting tree growth caused by climate change. Two divergent clones of Populus nigra (58-861 and Poli) originating from contrasting environments were subjected to water limitation (WL) to elucidate whether they differ in tolerance to drought, which mechanisms to avoid stress they exhibit and whether drought has an impact on the interactions between roots and shoots. Limiting water availability caused photosynthetic rate and total non-structural carbohydrate (TNC) levels to decrease in 58-861. However, starch-degrading enzyme activity and gene expression were induced in roots, and soluble sugar levels were higher than in well-watered (WW) plants. These data suggest that assimilation and partitioning of carbon to the roots are decreased, resulting in mobilization of stored starch. In contrast, the photosynthetic rate of Poli was reduced only late in the treatment, and carbohydrate levels in WL plants were higher than in WW plants. Superoxide dismutase (SOD) activity and gene expression were higher in Poli than in 58-861, even in WW plants, leading to a higher capacity to defend against oxidative stress.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19671097?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Soolanayakanahally, Raju Y</style></author><author><style face="normal" font="default" size="100%">Guy, Robert D</style></author><author><style face="normal" font="default" size="100%">Silim, Salim N</style></author><author><style face="normal" font="default" size="100%">Drewes, Eric C</style></author><author><style face="normal" font="default" size="100%">Schroeder, William R</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Enhanced assimilation rate and water use efficiency with latitude through increased photosynthetic capacity and internal conductance in balsam poplar (Populus balsamifera L.).</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">32</style></volume><pages><style face="normal" font="default" size="100%">1821-32</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In outdoor common gardens, high latitude populations of deciduous tree species often display higher assimilation rates (A) than low latitude populations, but they accomplish less height. To test whether trends in A reflect adaptation to growing season length or, alternatively, are garden growth artefacts, we examined variation in height increment and ecophysiological traits in a range-wide collection of Populus balsamifera L. populations from 21 provenances, during unconstrained growth in a greenhouse. Rooted cuttings, maintained without resource limitation under 21 h photoperiod for 90 d, displayed increasing height growth, A, leaf mass per area and leaf N per area with latitude whereas stomatal conductance (g(s)) showed no pattern. Water-use efficiency as indicated by both gas exchange and delta(13)C increased with latitude, whereas photosynthetic nitrogen-use efficiency decreased. Differences in delta(13)C were less than expected based on A/g(s), suggesting coextensive variation in internal conductance (g(m)). Analysis of A-C(i) curves on a subset of populations showed that high latitude genotypes had greater g(m) than low-latitude genotypes. We conclude that higher peak rates of height growth in high latitude genotypes of balsam poplar are supported by higher A, achieved partly through higher g(m), to help compensate for a shorter growing season.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19712064?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhang, Xiao</style></author><author><style face="normal" font="default" size="100%">Qin, Wenjuan</style></author><author><style face="normal" font="default" size="100%">Paice, Michael G</style></author><author><style face="normal" font="default" size="100%">Saddler, John N</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">High consistency enzymatic hydrolysis of hardwood substrates.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioresource technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bioresour. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">100</style></volume><pages><style face="normal" font="default" size="100%">5890-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The feasibility of using a laboratory peg mixer to carry out high consistency enzymatic hydrolysis of lignocellulosic substrates was investigated. Two hardwood substrates, unbleached hardwood pulp (UBHW) and organosolv pretreated poplar (OPP), were used in this study. Hydrolysis of UBHW and OPP at 20% substrate consistency led to a high glucose concentration in the final hydrolysate. For example, a 48 h enzymatic hydrolysis of OPP resulted in a hydrolysate with 158 g/L of glucose. This is the highest glucose concentration ever obtained from enzymatic hydrolysis of lignocellulosic substrates. Fermentation of UBHW and OPP hydrolysates with high glucose content led to high ethanol concentrations, 50.4 and 63.1 g/L, respectively after fermentation. Our results demonstrate that using common pulping equipment to carry out high consistency hydrolysis can overcome the rheological problems and greatly increase the sugar and ethanol concentrations after the hydrolysis and fermentation.</style></abstract><issue><style face="normal" font="default" size="100%">23</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19643602?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Joseph, Franklin</style></author><author><style face="normal" font="default" size="100%">Reeve-Fowkes, Amy</style></author><author><style face="normal" font="default" size="100%">Ewins, David</style></author><author><style face="normal" font="default" size="100%">Goenka, Niru</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Medicine at the sharp end.</style></title><secondary-title><style face="normal" font="default" size="100%">Clinical medicine (London, England)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Clin Med</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">630-1; author reply 631</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099383?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Mittal, Ashutosh</style></author><author><style face="normal" font="default" size="100%">Scott, Gary M</style></author><author><style face="normal" font="default" size="100%">Amidon, Thomas E</style></author><author><style face="normal" font="default" size="100%">Kiemle, David J</style></author><author><style face="normal" font="default" size="100%">Stipanovic, Arthur J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Quantitative analysis of sugars in wood hydrolyzates with 1H NMR during the autohydrolysis of hardwoods.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioresource technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bioresour. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">100</style></volume><pages><style face="normal" font="default" size="100%">6398-406</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The focus of this work was to determine the utility of (1)H NMR spectroscopy in the quantification of sugars resulting from the solubilization of hemicelluloses during the autohydrolysis of hardwoods and the use of this technique to evaluate the kinetics of this process over a range of temperatures and times. Yields of residual xylan, xylooligomers, xylose, glucose, and the degraded products of sugars, i.e., furfural and HMF (5-hydroxymethyl furfural), were determined. The monosaccharide and oligomer contents were quantified with a recently developed high resolution (1)H NMR spectroscopic analysis. This method provided precise measurement of the residual xylan and cellulose remaining in the extracted wood samples and xylose and glucose in the hydrolyzates. NMR was found to exhibit good repeatability and provided carbohydrate compositional results comparable to published methods for sugar maple and aspen woods.</style></abstract><issue><style face="normal" font="default" size="100%">24</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19674893?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kendall, D</style></author><author><style face="normal" font="default" size="100%">Hazarika, R</style></author><author><style face="normal" font="default" size="100%">Harrop, J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The value of the post-take ward round.</style></title><secondary-title><style face="normal" font="default" size="100%">Clinical medicine (London, England)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Clin Med</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">632-3</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099384?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Coleman, Heather D</style></author><author><style face="normal" font="default" size="100%">Yan, Jimmy</style></author><author><style face="normal" font="default" size="100%">Mansfield, Shawn D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Sucrose synthase affects carbon partitioning to increase cellulose production and altered cell wall ultrastructure.</style></title><secondary-title><style face="normal" font="default" size="100%">Proceedings of the National Academy of Sciences of the United States of America</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Proc. Natl. Acad. Sci. U.S.A.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Aug 4</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">106</style></volume><pages><style face="normal" font="default" size="100%">13118-23</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Overexpression of the Gossypium hirsutum sucrose synthase (SuSy) gene under the control of 2 promoters was examined in hybrid poplar (Populus alba x grandidentata). Analysis of RNA transcript abundance, enzyme activity, cell wall composition, and soluble carbohydrates revealed significant changes in the transgenic lines. All lines showed significantly increased SuSy enzyme activity in developing xylem. This activity manifested in altered secondary cell wall cellulose content per dry weight in all lines, with increases of 2% to 6% over control levels, without influencing plant growth. The elevated concentration of cellulose was associated with an increase in cell wall crystallinity but did not alter secondary wall microfibril angle. This finding suggests that the observed increase in crystallinity is a function of altered carbon partitioning to cellulose biosynthesis rather than the result of tension wood formation. Furthermore, the augmented deposition of cellulose in the transgenic lines resulted in thicker xylem secondary cell wall and consequently improved wood density. These findings clearly implicate SuSy as a key regulator of sink strength in poplar trees and demonstrate the tight association of SuSy with cellulose synthesis and secondary wall formation.</style></abstract><issue><style face="normal" font="default" size="100%">31</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19625620?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Funes, Hernán</style></author><author><style face="normal" font="default" size="100%">Zerba, Eduardo</style></author><author><style face="normal" font="default" size="100%">González Audino, Paola</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Comparison of three types of traps baited with sexual pheromones for ambrosia beetle Megaplatypus mutatus (Coleoptera: Platypodinae) in poplar plantations.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of economic entomology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Econ. Entomol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">102</style></volume><pages><style face="normal" font="default" size="100%">1546-50</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Megaplatypus mutatus (Coleoptera: Platypodinae) is an ambrosia beetle native to South America that only attacks standing live trees and is a serious problem for commercial poplar (Populus L.; Salicaceae) plantations in Argentina. The development of traps baited with synthetic pheromones that can be used for monitoring M. mutatus in infested poplar plantations is an important goal in preventive programs. Pioneer male M. mutatus emit a pheromone composed mainly by (+)-sulcatol and sulcatone. In the current study, we tested their release rates from several polymeric reservoir systems, to develop and manufacture a pheromone-releasing device. The efficacy of three different types of traps was evaluated in the field. Single funnel traps equipped with cross-vanes (CIPEIN-CV) captured significantly more insects than multiple funnel traps (LINDGREN) and simple funnel traps (CIPEIN-F).</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19736767?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Balestrazzi, Alma</style></author><author><style face="normal" font="default" size="100%">Botti, Silvia</style></author><author><style face="normal" font="default" size="100%">Zelasco, Samantha</style></author><author><style face="normal" font="default" size="100%">Biondi, Stefania</style></author><author><style face="normal" font="default" size="100%">Franchin, Cinzia</style></author><author><style face="normal" font="default" size="100%">Calligari, Paolo</style></author><author><style face="normal" font="default" size="100%">Racchi, Milvia</style></author><author><style face="normal" font="default" size="100%">Turchi, Adelaide</style></author><author><style face="normal" font="default" size="100%">Lingua, Guido</style></author><author><style face="normal" font="default" size="100%">Berta, Graziella</style></author><author><style face="normal" font="default" size="100%">Carbonera, Daniela</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Expression of the PsMTA1 gene in white poplar engineered with the MAT system is associated with heavy metal tolerance and protection against 8-hydroxy-2'-deoxyguanosine mediated-DNA damage.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant cell reports</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Rep.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">1179-92</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Marker-free transgenic white poplar (Populus alba L., cv 'Villafranca') plants, expressing the PsMT (A1) gene from Pisum sativum for a metallothionein-like protein, were produced by Agrobacterium tumefaciens-mediated transformation. The 35SCaMV-PsMT (A1)-NosT cassette was inserted into the ipt-type vector pMAT22. The occurrence of the abnormal ipt-shooty phenotype allowed the visual selection of transformants, while the yeast site-specific recombination R/RS system was responsible for the excision of the undesired vector sequences with the consequent recovery of normal marker-free transgenic plants. Molecular analyses confirmed the presence of the 35SCaMV-PsMT (A1)-NosT cassette and transgene expression. Five selected lines were further characterized, revealing the ability to withstand heavy metal toxicity. They survived 0.1 mM CuCl(2), a concentration which strongly affected the nontransgenic plants. Moreover, root development was only slightly affected by the ectopic expression of the transgene. Reactive oxygen species were accumulated to a lower extent in leaf tissues of multi-auto-transformation (MAT)-PsMT(A1) plants exposed to copper and zinc, compared to control plants. Tolerance to photo-oxidative stress induced by paraquat was another distinctive feature of the MAT-PsMT(A1) lines. Finally, low levels of DNA damage were detected by quantifying the amounts of 8-hydroxy-2'-deoxyguanosine in leaf tissues of the transgenic plants exposed to copper.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19506883?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Schmidt, M</style></author><author><style face="normal" font="default" size="100%">Schwartzberg, A M</style></author><author><style face="normal" font="default" size="100%">Perera, P N</style></author><author><style face="normal" font="default" size="100%">Weber-Bargioni, A</style></author><author><style face="normal" font="default" size="100%">Carroll, A</style></author><author><style face="normal" font="default" size="100%">Sarkar, P</style></author><author><style face="normal" font="default" size="100%">Bosneaga, E</style></author><author><style face="normal" font="default" size="100%">Urban, J J</style></author><author><style face="normal" font="default" size="100%">Song, J</style></author><author><style face="normal" font="default" size="100%">Balakshin, M Y</style></author><author><style face="normal" font="default" size="100%">Capanema, E A</style></author><author><style face="normal" font="default" size="100%">Auer, M</style></author><author><style face="normal" font="default" size="100%">Adams, P D</style></author><author><style face="normal" font="default" size="100%">Chiang, V L</style></author><author><style face="normal" font="default" size="100%">Schuck, P James</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Label-free in situ imaging of lignification in the cell wall of low lignin transgenic Populus trichocarpa.</style></title><secondary-title><style face="normal" font="default" size="100%">Planta</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Planta</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">230</style></volume><pages><style face="normal" font="default" size="100%">589-97</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Chemical imaging by confocal Raman microscopy has been used for the visualization of the cellulose and lignin distribution in wood cell walls. Lignin reduction in wood can be achieved by, for example, transgenic suppression of a monolignol biosynthesis gene encoding 4-coumarate-CoA ligase (4CL). Here, we use confocal Raman microscopy to compare lignification in wild type and lignin-reduced 4CL transgenic Populus trichocarpa stem wood with spatial resolution that is sub-microm. Analyzing the lignin Raman bands in the spectral region between 1,600 and 1,700 cm(-1), differences in lignin signal intensity and localization are mapped in situ. Transgenic reduction of lignin is particularly pronounced in the S2 wall layer of fibers, suggesting that such transgenic approach may help overcome cell wall recalcitrance to wood saccharification. Spatial heterogeneity in the lignin composition, in particular with regard to ethylenic residues, is observed in both samples.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19526248?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Scherling, Christian</style></author><author><style face="normal" font="default" size="100%">Ulrich, Kristina</style></author><author><style face="normal" font="default" size="100%">Ewald, Dietrich</style></author><author><style face="normal" font="default" size="100%">Weckwerth, Wolfram</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A metabolic signature of the beneficial interaction of the endophyte paenibacillus sp. isolate and in vitro-grown poplar plants revealed by metabolomics.</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular plant-microbe interactions : MPMI</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Plant Microbe Interact.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">22</style></volume><pages><style face="normal" font="default" size="100%">1032-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Metabolic profiling via gas chromatography coupled to mass spectrometry was used to investigate the influence of endophytic bacteria on shoots of in vitro-grown poplar plants free from culturable endophytic bacteria. The results demonstrate that the occurrence of an endophytic Paenibacillus strain strongly affects the composition of the plant metabolites of in vitro-grown poplars. Eleven metabolites were significantly changed between inoculated and non-inoculated poplar plants as determined by two independent experiments. Detected shifts in the primary metabolism of the poplar plants pointed to a mutualistic interaction between bacteria able to fix nitrogen and the host plant with altered nitrogen assimilation patterns. The corresponding metabolic signature comprises increased asparagine and urea levels as well as depleted sugars and organic acids of the tricarboxylic acid cycle. These observations coincide with the fact that the Paenibacillus sp. strain P22 is able to grow without nitrogen in the medium, indicating nitrogen fixation from the air also known from other Paenibacillus spp. In combination with the detected plant-growth-promoting effects of the endophyte Paenibacillus P22, a novel mutualistic interaction is observed.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19589078?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Si, Chuan-Ling</style></author><author><style face="normal" font="default" size="100%">Kim, Jin-Kyu</style></author><author><style face="normal" font="default" size="100%">Bae, Young-Soo</style></author><author><style face="normal" font="default" size="100%">Li, Shu-Ming</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Phenolic compounds in the leaves of Populus ussuriensis and their antioxidant activities.</style></title><secondary-title><style face="normal" font="default" size="100%">Planta medica</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Planta Med.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">75</style></volume><pages><style face="normal" font="default" size="100%">1165-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Two new phenolic glucosides [isograndidentatin A (1) isograndidentatin B (2)], 5 known phenolic glucosides [grandidentatin (3), salireposide (4), populoside (5), populoside A (6), and salicortin (7)], and 2 known phenolic acids [P-coumaric acid (8) and caffeic acid (9)] were isolated from the leaves of Populus ussuriensis. Structure elucidation of 1 and 2 was achieved through extensive spectroscopic techniques. Compounds 1-6 and 9 showed significant antioxidant activities, which were evaluated by the DPPH radical-scavenging method (IC(50) values of 6.68, 6.61, 6.75, 6.84, 6.76, 6.79, and 5.92 microM, respectively) and the ABTS .+ radical-scavenging system (TEAC values of 1.21, 1.28, 1.26, 1.05, 1.69, 1.60, and 2.00 mM, respectively).</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19296432?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Dillen, Sophie Y</style></author><author><style face="normal" font="default" size="100%">Marron, Nicolas</style></author><author><style face="normal" font="default" size="100%">Sabatti, Maurizio</style></author><author><style face="normal" font="default" size="100%">Ceulemans, Reinhart</style></author><author><style face="normal" font="default" size="100%">Bastien, Catherine</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Relationships among productivity determinants in two hybrid poplar families grown during three years at two contrasting sites.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">975-87</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The objective of this study was to evaluate the environmental, temporal and genetic stability of the relationships between growth and a selection of tree architectural, leaf and phenological traits (selection based on the conclusions of previous studies carried out on the same experimental trial). Therefore, the growth of two hybrid families, Populus deltoides 'S9-2' x Populus nigra 'Ghoy' (D x N family, 180 F(1)) and P. deltoides 'S9-2' x Populus trichocarpa 'V24' (D x T family, 182 F(1)), was investigated during a 3-year period at two sites, i.e., in northern Italy and central France. At the end of the second growing season, all trees were coppiced and the resprouts were thinned to a single stem. At the end of each growing season, stem circumference and height were measured for all F(1) hybrids. The number of sylleptic branches, individual leaf area (LA) and petiole length of the largest leaf along the main stem, production of new leaves, bud flush and bud set were estimated for a selection of genotypes (31 F(1)) per family at each site during the course of the 3-year experiment. The D x T family was clearly the most productive family and displayed the highest heterosis values. However, there appeared to be a compromise between good growth at a given site and stability between the two different sites, both at family and at genotype levels. Particularly, the less performing trees were stable between Italy and France. Among the studied growth components, the number of sylleptic branches and individual LA of the largest leaf along the main stem were the best growth predictors, irrespective of site and family. Growth strategies in terms of leaf development differed between the two families. Hence, leaf production rate was strongly associated with growth of the D x N family only. These results have important consequences for the use of the studied traits as selection criteria in breeding programmes.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19483184?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Neiman, Maurine</style></author><author><style face="normal" font="default" size="100%">Olson, Matthew S</style></author><author><style face="normal" font="default" size="100%">Tiffin, Peter</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Selective histories of poplar protease inhibitors: elevated polymorphism, purifying selection, and positive selection driving divergence of recent duplicates.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">183</style></volume><pages><style face="normal" font="default" size="100%">740-50</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">To further our understanding of plant defense evolution and the consistency of selection at the nucleotide level we analysed polymorphism data from five protease inhibitor (PI) genes in Populus balsamifera. We compared diversity at the five PI genes to diversity at nondefense loci in both range-wide samples as well as in two subpopulations, one from the northern edge of the species range and one from the southern edge of the range. We also compared our data with previously reported diversity in Populus tremula, a European species with similar ecology to North American P. balsamifera. The PIs show diverse histories, including repeated bouts of positive selection and excess diversity. These genes also exhibit diverse histories in P. tremula but the signatures of selection acting at the specific loci differed between the species. One locus, KTI3, segregates several recent duplicates that show evidence of either positive selection or relaxed selective constraints. The patterns of diversity at the PIs varied within P. balsamifera and between two closely related species. The lack of consistent patterns suggests that evolution of host defense genes, including adaptations to enemy-imposed selection, may often be lineage- and gene-specific.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19566812?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bonadei, Martina</style></author><author><style face="normal" font="default" size="100%">Balestrazzi, Alma</style></author><author><style face="normal" font="default" size="100%">Frigerio, Barbara</style></author><author><style face="normal" font="default" size="100%">Carbonera, Daniela</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Soil persistence of DNA from transgenic poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental biosafety research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ Biosafety Res</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Apr-Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">8</style></volume><pages><style face="normal" font="default" size="100%">79-86</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The presence of recombinant DNA in soil cultivated with white poplars (Populus alba L.) expressing either the bar transgene for herbicide tolerance or the StSy transgene for resveratrol production, respectively, was investigated in a greenhouse over a 20-month period. The bar trial included the transgenic lines 5P56 and 6EA22P56 and the untransformed line, while the StSy trial was established with the transgenic lines 5EAC1 and 12EAC1 and with the untransformed line. All the transgenic poplars harbored the nptII marker gene. Plantlets were cultivated in pots, and soil samples were mixed in order to obtain composite pools which were used for molecular analyses. The 35SCaMV-bar (1504 bp), 35SCaMV-StSy (1403 bp) and NosP-nptII (1188 bp) sequences were detected in total DNA extracted from soil samples taken at different times after planting, using PCR/Southern blot hybridization. Microcosm experiments, carried out to assess the effects of temperature and DNA purity on transgene persistence, revealed only a partial correlation between the intensity of hybridization signals and the parameters tested.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19833075?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Love, Jonathan</style></author><author><style face="normal" font="default" size="100%">Björklund, Simon</style></author><author><style face="normal" font="default" size="100%">Vahala, Jorma</style></author><author><style face="normal" font="default" size="100%">Hertzberg, Magnus</style></author><author><style face="normal" font="default" size="100%">Kangasjärvi, Jaakko</style></author><author><style face="normal" font="default" size="100%">Sundberg, Björn</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Ethylene is an endogenous stimulator of cell division in the cambial meristem of Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">Proceedings of the National Academy of Sciences of the United States of America</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Proc. Natl. Acad. Sci. U.S.A.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Apr 7</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">106</style></volume><pages><style face="normal" font="default" size="100%">5984-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The plant hormone ethylene is an important signal in plant growth responses to environmental cues. In vegetative growth, ethylene is generally considered as a regulator of cell expansion, but a role in the control of meristem growth has also been suggested based on pharmacological experiments and ethylene-overproducing mutants. In this study, we used transgenic ethylene-insensitive and ethylene-overproducing hybrid aspen (Populus tremula x tremuloides) in combination with experiments using an ethylene perception inhibitor [1-methylcyclopropene (1-MCP)] to demonstrate that endogenous ethylene produced in response to leaning stimulates cell division in the cambial meristem. This ethylene-controlled growth gives rise to the eccentricity of Populus stems that is formed in association with tension wood.</style></abstract><issue><style face="normal" font="default" size="100%">14</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19293381?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Couturier, Jeremy</style></author><author><style face="normal" font="default" size="100%">Koh, Cha San</style></author><author><style face="normal" font="default" size="100%">Zaffagnini, Mirko</style></author><author><style face="normal" font="default" size="100%">Winger, Alison M</style></author><author><style face="normal" font="default" size="100%">Gualberto, Jose Manuel</style></author><author><style face="normal" font="default" size="100%">Corbier, Catherine</style></author><author><style face="normal" font="default" size="100%">Decottignies, Paulette</style></author><author><style face="normal" font="default" size="100%">Jacquot, Jean-Pierre</style></author><author><style face="normal" font="default" size="100%">Lemaire, Stéphane D</style></author><author><style face="normal" font="default" size="100%">Didierjean, Claude</style></author><author><style face="normal" font="default" size="100%">Rouhier, Nicolas</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Structure-function relationship of the chloroplastic glutaredoxin S12 with an atypical WCSYS active site.</style></title><secondary-title><style face="normal" font="default" size="100%">The Journal of biological chemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Biol. Chem.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Apr 3</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">284</style></volume><pages><style face="normal" font="default" size="100%">9299-310</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Glutaredoxins (Grxs) are efficient catalysts for the reduction of mixed disulfides in glutathionylated proteins, using glutathione or thioredoxin reductases for their regeneration. Using GFP fusion, we have shown that poplar GrxS12, which possesses a monothiol (28)WCSYS(32) active site, is localized in chloroplasts. In the presence of reduced glutathione, the recombinant protein is able to reduce in vitro substrates, such as hydroxyethyldisulfide and dehydroascorbate, and to regenerate the glutathionylated glyceraldehyde-3-phosphate dehydrogenase. Although the protein possesses two conserved cysteines, it is functioning through a monothiol mechanism, the conserved C terminus cysteine (Cys(87)) being dispensable, since the C87S variant is fully active in all activity assays. Biochemical and crystallographic studies revealed that Cys(87) exhibits a certain reactivity, since its pK(a) is around 5.6. Coupled with thiol titration, fluorescence, and mass spectrometry analyses, the resolution of poplar GrxS12 x-ray crystal structure shows that the only oxidation state is a glutathionylated derivative of the active site cysteine (Cys(29)) and that the enzyme does not form inter- or intramolecular disulfides. Contrary to some plant Grxs, GrxS12 does not incorporate an iron-sulfur cluster in its wild-type form, but when the active site is mutated into YCSYS, it binds a [2Fe-2S] cluster, indicating that the single Trp residue prevents this incorporation.</style></abstract><issue><style face="normal" font="default" size="100%">14</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19158074?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kieffer, Pol</style></author><author><style face="normal" font="default" size="100%">Schröder, Peter</style></author><author><style face="normal" font="default" size="100%">Dommes, Jacques</style></author><author><style face="normal" font="default" size="100%">Hoffmann, Lucien</style></author><author><style face="normal" font="default" size="100%">Renaut, Jenny</style></author><author><style face="normal" font="default" size="100%">Hausman, Jean-François</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Proteomic and enzymatic response of poplar to cadmium stress.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of proteomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J Proteomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Apr 13</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">72</style></volume><pages><style face="normal" font="default" size="100%">379-96</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">This study highlights proteomic and enzymatic changes in roots and leaves of actively growing poplar plants upon a cadmium stress exposure. Proteomic changes in response to a short-term (14 days), as well as a longer term (56 days) treatment are observed between the different organs. In leaves, stress-related proteins, like heat shock proteins, proteinases and pathogenesis-related proteins increased in abundance. A response similar to a hypersensitive response upon plant-pathogen interaction seemed to be induced. Concerning roots it appeared that the metabolic impact of cadmium was more deleterious than in leaves. This is evidenced by the early increase in abundance of many typical stress-related proteins like heat shock proteins, or glutathione-S-transferases, while most proteins from the primary metabolism (glycolysis, tricarboxylic acid cycle, nitrogen metabolism, sulfur metabolism) were severely decreased in abundance. Additionally the impact of cadmium on the glutathione metabolism could be assessed by activity assays of several important enzymes. Cadmium treatment had an inhibitory effect on glutathione reductase and ascorbate peroxidase in leaves, but not in roots. Conversely, glutathione-S-transferase showed a higher activity (and abundance) in roots but not in leaves.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19367735?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lu, Shanfa</style></author><author><style face="normal" font="default" size="100%">Sun, Ying-Hsuan</style></author><author><style face="normal" font="default" size="100%">Chiang, Vincent L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Adenylation of plant miRNAs.</style></title><secondary-title><style face="normal" font="default" size="100%">Nucleic acids research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Nucleic Acids Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">37</style></volume><pages><style face="normal" font="default" size="100%">1878-85</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The modification or degradation of RNAs including miRNAs may play vital roles in regulating RNA functions. The polyadenylation- and exosome-mediated RNA decay is involved in the degradation of plant RNAs including the primary miRNA processing intermediates. However, plant miRNA levels are not affected by exosome depletion. Here, we report the cloning of a large number of 5' and/or 3' truncated versions of the known miRNAs from various tissues of Populus trichocarpa (black cottonwood). It suggests that plant miRNAs may be degraded through either 5' to 3' or 3' to 5' exonucleolytic digestion. We also show that a significant portion of the isolated miRNAs contains, at the 3'-end, one or a few post-transcriptionally added adenylic acid residues, which are distinct in length from the polyadenylate tail added to other plant RNAs for exosome-mediated degradation. Using an in vitro miRNA degradation system, where synthesized miRNA oligos were degraded in extracts of P. trichocarpa cells, we revealed that the adenylated miRNAs were degraded slower than others without adenylation. It indicates that addition of adenylic acid residues on the 3'-end plays a negative role in miRNA degradation. Our results provide new information for understanding the mechanism of miRNA degradation.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19188256?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Srivastava, Vaibhav</style></author><author><style face="normal" font="default" size="100%">Srivastava, Manoj Kumar</style></author><author><style face="normal" font="default" size="100%">Chibani, Kamel</style></author><author><style face="normal" font="default" size="100%">Nilsson, Robert</style></author><author><style face="normal" font="default" size="100%">Rouhier, Nicolas</style></author><author><style face="normal" font="default" size="100%">Melzer, Michael</style></author><author><style face="normal" font="default" size="100%">Wingsle, Gunnar</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Alternative splicing studies of the reactive oxygen species gene network in Populus reveal two isoforms of high-isoelectric-point superoxide dismutase.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">149</style></volume><pages><style face="normal" font="default" size="100%">1848-59</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Recent evidence has shown that alternative splicing (AS) is widely involved in the regulation of gene expression, substantially extending the diversity of numerous proteins. In this study, a subset of expressed sequence tags representing members of the reactive oxygen species gene network was selected from the PopulusDB database to investigate AS mechanisms in Populus. Examples of all known types of AS were detected, but intron retention was the most common. Interestingly, the closest Arabidopsis (Arabidopsis thaliana) homologs of half of the AS genes identified in Populus are not reportedly alternatively spliced. Two genes encoding the protein of most interest in our study (high-isoelectric-point superoxide dismutase [hipI-SOD]) have been found in black cottonwood (Populus trichocarpa), designated PthipI-SODC1 and PthipI-SODC2. Analysis of the expressed sequence tag libraries has indicated the presence of two transcripts of PthipI-SODC1 (hipI-SODC1b and hipI-SODC1s). Alignment of these sequences with the PthipI-SODC1 gene showed that hipI-SODC1b was 69 bp longer than hipI-SODC1s due to an AS event involving the use of an alternative donor splice site in the sixth intron. Transcript analysis showed that the splice variant hipI-SODC1b was differentially expressed, being clearly expressed in cambial and xylem, but not phloem, regions. In addition, immunolocalization and mass spectrometric data confirmed the presence of hipI-SOD proteins in vascular tissue. The functionalities of the spliced gene products were assessed by expressing recombinant hipI-SOD proteins and in vitro SOD activity assays.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19176719?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ramlal, Elizabeth</style></author><author><style face="normal" font="default" size="100%">Yemshanov, Denys</style></author><author><style face="normal" font="default" size="100%">Fox, Glenn</style></author><author><style face="normal" font="default" size="100%">McKenney, Daniel</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A bioeconomic model of afforestation in Southern Ontario: integration of fiber, carbon and municipal biosolids values.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of environmental management</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Environ. Manage.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">90</style></volume><pages><style face="normal" font="default" size="100%">1833-43</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">This study explores the economic attractiveness of afforestation as a strategy for the joint production of fibre, carbon storage and biosolids (treated municipal sewage sludge) disposal for municipalities in Southern and Central Ontario, Canada. We use a spatial, stochastic model, the Canadian Forest Service Afforestation Feasibility Model (CFS-AFM), to simulate a range of spatial biosolids application scenarios in hybrid poplar afforestation projects. Results suggest that such joint afforestation strategies could be financially attractive. Significant cost savings can be expected through decreases in transportation distances and avoided waste disposal fees. Sensitivity analysis is used to examine the effects of variations in critical model parameters on net present values. Our findings indicate that waste disposal savings from application of biosolids on hybrid poplar plantations combined with incentives for landowners to sequester carbon can easily compete with agricultural land rental values in some regions of Ontario. Social acceptance of this kind of activity, however, may be an impediment to adoption.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19185971?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Fracheboud, Yvan</style></author><author><style face="normal" font="default" size="100%">Luquez, Virginia</style></author><author><style face="normal" font="default" size="100%">Björkén, Lars</style></author><author><style face="normal" font="default" size="100%">Sjödin, Andreas</style></author><author><style face="normal" font="default" size="100%">Tuominen, Hannele</style></author><author><style face="normal" font="default" size="100%">Jansson, Stefan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The control of autumn senescence in European aspen.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">149</style></volume><pages><style face="normal" font="default" size="100%">1982-91</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The initiation, progression, and natural variation of autumn senescence in European aspen (Populus tremula) was investigated by monitoring chlorophyll degradation in (1) trees growing in natural stands and (2) cloned trees growing in a greenhouse under various light regimes. The main trigger for the initiation of autumn senescence in aspen is the shortening photoperiod, but there was a large degree of variation in the onset of senescence, both within local populations and among trees originating from different populations, where it correlated with the latitude of their respective origins. The variation for onset of senescence with a population was much larger than the variation of bud set. Once started, autumn senescence was accelerated by low temperature and longer nights, and clones that started to senescence late had a faster senescence. Bud set and autumn senescence appeared to be under the control of two independent critical photoperiods, but senescence could not be initiated until a certain time after bud set, suggesting that bud set and growth arrest are important for the trees to acquire competence to respond to the photoperiodic trigger to undergo autumn senescence. A timetable of events related to bud set and autumn senescence is presented.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19201914?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Marković, D M</style></author><author><style face="normal" font="default" size="100%">Novović, I</style></author><author><style face="normal" font="default" size="100%">Vilotić, D</style></author><author><style face="normal" font="default" size="100%">Ignjatović, Lj</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Determination of As in tree-rings of poplar (Populus alba L.) by U-shaped DC arc.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental monitoring and assessment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ Monit Assess</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">151</style></volume><pages><style face="normal" font="default" size="100%">377-82</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">An argon-stabilized U-shaped DC arc with a system for aerosol introduction was used for determination of As in poplar (Populus alba L.) tree-rings. After optimization of the operating parameters and selection of the most appropriate signal integration time (30 s), the limit of detection for As was reduced to 15.0 ng/mL. This detection limit obtained with the optimal integration time was compared with those for other methods: inductively coupled plasma-atomic emission spectrometry (ICP-AES), direct coupled plasma-atomic emission spectrometry (DCP-AES), microwave induced plasma-atomic emission spectrometry (MIP-AES) and improved thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS). Arsenic is toxic trace element which can adversely affect plant, animal and human health. As an indicator of environment pollution we collected poplar tree-rings from two locations. The first area was close to the &quot;Nikola Tesla&quot; (TENT-A) power plant, Obrenovac, while the other was in the urban area of Novi Sad. In all cases elevated average concentrations of As were registered in poplar tree-rings from the Obrenovac location.</style></abstract><issue><style face="normal" font="default" size="100%">1-4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18351436?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Barbehenn, Raymond V</style></author><author><style face="normal" font="default" size="100%">Jaros, Adam</style></author><author><style face="normal" font="default" size="100%">Lee, Grace</style></author><author><style face="normal" font="default" size="100%">Mozola, Cara</style></author><author><style face="normal" font="default" size="100%">Weir, Quentin</style></author><author><style face="normal" font="default" size="100%">Salminen, Juha-Pekka</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Hydrolyzable tannins as &quot;quantitative defenses&quot;: limited impact against Lymantria dispar caterpillars on hybrid poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of insect physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Insect Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">55</style></volume><pages><style face="normal" font="default" size="100%">297-304</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The high levels of tannins in many tree leaves are believed to cause decreased insect performance, but few controlled studies have been done. This study tested the hypothesis that higher foliar tannin levels produce higher concentrations of semiquinone radicals (from tannin oxidation) in caterpillar midguts, and that elevated levels of radicals are associated with increased oxidative stress in midgut tissues and decreased larval performance. The tannin-free leaves of hybrid poplar (Populus tremulaxP. alba) were treated with hydrolyzable tannins, producing concentrations of 0%, 7.5% or 15% dry weight, and fed to Lymantria dispar caterpillars. As expected, larvae that ingested control leaves contained no measurable semiquinone radicals in the midgut, those that ingested 7.5% hydrolyzable tannin contained low levels of semiquinone radicals, and those that ingested 15% tannin contained greatly increased levels of semiquinone radicals. Ingested hydrolyzable tannins were also partially hydrolyzed in the midgut. However, increased levels of semiquinone radicals in the midgut were not associated with oxidative stress in midgut tissues. Instead, it appears that tannin consumption was associated with increased metabolic costs, as measured by the decreased efficiency of conversion of digested matter to body mass (ECD). Decreased ECD, in turn, decreased the overall efficiency of conversion of ingested matter to body mass (ECI). Contrary to our hypothesis, L. dispar larvae were able to maintain similar growth rates across all tannin treatment levels, in part, because of compensatory feeding. We conclude that hydrolyzable tannins act as &quot;quantitative defenses&quot; in the sense that high levels appear to be necessary to increase levels of semiquinone radicals in the midguts of caterpillars. However, these putative resistance factors are not sufficient to decrease the performance of tannin-tolerant caterpillars such as L. dispar.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19111746?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Capitani, Donatella</style></author><author><style face="normal" font="default" size="100%">Brilli, Federico</style></author><author><style face="normal" font="default" size="100%">Mannina, Luisa</style></author><author><style face="normal" font="default" size="100%">Proietti, Noemi</style></author><author><style face="normal" font="default" size="100%">Loreto, Francesco</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">In situ investigation of leaf water status by portable unilateral nuclear magnetic resonance.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">149</style></volume><pages><style face="normal" font="default" size="100%">1638-47</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A portable unilateral nuclear magnetic resonance (NMR) instrument was used to detect in field conditions the water status of leaves of herbaceous crops (Zea mays, Phaseolus vulgaris), mesophyllous trees (Populus nigra), and natural Mediterranean vegetation characterized by water-spending shrubs (Cistus incanus) and water-saving sclerophyllous trees (Quercus ilex). A good relationship was observed between NMR signal, leaf relative water content, and leaf transpiration in herbaceous leaves undergoing fast dehydration or slowly developing a drought stress. A relationship was also observed between NMR signal and water potential of Populus leaves during the development of a water stress and when leaves recovered from the stress. In the natural vegetation, the relationship between NMR signal and water status was found in Cistus, the species characterized by high transpiration rates, when measured during a drought stress period and after a rainfall. In the case of the sclerophyllous Quercus, the NMR signal, the relative water content, and the transpiration rate did not change at different leaf water status, possibly because a large amount of water is compartmentalized in cellular structures and macromolecules. The good association between NMR signal and relative water content was lost in leaves exposed for 24 h to dehydration or to an osmotic stress caused by polyethylene glycol feeding. At this time, the transverse relaxation time became longer than in leaves maintained under optimal water conditions, and two indicators of membrane damage, the ion leakage and the emission of products of membrane lipoxygenation [(Z)-3-hexenal, (Z)-3-hexenol, and (E)-2-hexenol], increased. These results taken all together give information on the physiological state of a leaf under a developing stress and show the usefulness of the NMR instrumentation for screening vegetation health and fitness in natural and cultivated conditions. It is concluded that the portable unilateral NMR instrument may be usefully employed in field conditions to monitor nondestructively the water status of plants and to assist agricultural practices, such as irrigation scheduling, to minimize stomatal closure and the consequent limitation to plant production.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19193862?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Mohapatra, Sridev</style></author><author><style face="normal" font="default" size="100%">Minocha, Rakesh</style></author><author><style face="normal" font="default" size="100%">Long, Stephanie</style></author><author><style face="normal" font="default" size="100%">Minocha, Subhash C</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Putrescine overproduction negatively impacts the oxidative state of poplar cells in culture.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology and biochemistry : PPB / Société française de physiologie végétale</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol. Biochem.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">47</style></volume><pages><style face="normal" font="default" size="100%">262-71</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">While polyamines (PAs) have been suggested to protect cells against Reactive Oxygen Species (ROS), their catabolism is known to generate ROS. We compared the activities of several enzymes and cellular metabolites involved in the ROS scavenging pathways in two isogenic cell lines of poplar (Populus nigraxmaximowiczii) differing in their PA contents. Whereas the control cell line was transformed with beta-glucuronidase (GUS), the other, called HP (High Putrescine), was transformed with a mouse ornithine decarboxylase (mODC) gene. The expression of mODC resulted in several-fold increased production of putrescine as well its enhanced catabolism. The two cell lines followed a similar trend of growth over the seven-day culture cycle, but the HP cells had elevated levels of soluble proteins. Accumulation of H(2)O(2) was higher in the HP cells than the control cells, and so were the activities of glutathione reductase and monodehydroascorbate reductase; the activity of ascorbate peroxidase was lower in the former. The contents of reduced glutathione and glutamate were significantly lower in the HP cells but proline was higher on some days of analysis. There was a small difference in mitochondrial activity between the two cell lines, and the HP cells showed increased membrane damage. In the HP cells, increased accumulation of Ca was concomitant with lower accumulation of K. We conclude that, while increased putrescine accumulation may have a protective role against ROS in plants, enhanced turnover of putrescine actually can make them vulnerable to increased oxidative damage.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19136266?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Courtois-Moreau, Charleen L</style></author><author><style face="normal" font="default" size="100%">Pesquet, Edouard</style></author><author><style face="normal" font="default" size="100%">Sjödin, Andreas</style></author><author><style face="normal" font="default" size="100%">Muñiz, Luis</style></author><author><style face="normal" font="default" size="100%">Bollhöner, Benjamin</style></author><author><style face="normal" font="default" size="100%">Kaneda, Minako</style></author><author><style face="normal" font="default" size="100%">Samuels, Lacey</style></author><author><style face="normal" font="default" size="100%">Jansson, Stefan</style></author><author><style face="normal" font="default" size="100%">Tuominen, Hannele</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A unique program for cell death in xylem fibers of Populus stem.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">58</style></volume><pages><style face="normal" font="default" size="100%">260-74</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Maturation of the xylem elements involves extensive deposition of secondary cell-wall material and autolytic processes resulting in cell death. We describe here a unique type of cell-death program in xylem fibers of hybrid aspen (Populus tremula x P. tremuloides) stems, including gradual degradative processes in both the nucleus and cytoplasm concurrently with the phase of active cell-wall deposition. Nuclear DNA integrity, as determined by TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling) and Comet (single-cell gel electrophoresis) assays, was compromised early during fiber maturation. In addition, degradation of the cytoplasmic contents, as detected by electron microscopy of samples fixed by high-pressure freezing/freeze substitution (HPF-FS), was gradual and resulted in complete loss of the cytoplasmic contents well before the loss of vacuolar integrity, which is considered to be the moment of death. This type of cell death differs significantly from that seen in xylem vessels. The loss of vacuolar integrity, which is thought to initiate cell degradative processes in the xylem vessels, is one of the last processes to occur before the final autolysis of the remaining cell contents in xylem fibers. High-resolution microarray analysis in the vascular tissues of Populus stem, combined with in silico analysis of publicly available data repositories, suggests the involvement of several previously uncharacterized transcription factors, ethylene, sphingolipids and light signaling as well as autophagy in the control of fiber cell death.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19175765?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wu, Rui-Fen</style></author><author><style face="normal" font="default" size="100%">Shen, Jian-Guo</style></author><author><style face="normal" font="default" size="100%">Yan, Wei-Xiong</style></author><author><style face="normal" font="default" size="100%">Zhang, Hua</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Impact of climate warming on phenophase of Populus tomentosa in Inner Mongolia].</style></title><secondary-title><style face="normal" font="default" size="100%">Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ying Yong Sheng Tai Xue Bao</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">20</style></volume><pages><style face="normal" font="default" size="100%">785-90</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Based on the 1982-2006 data of air temperature and of the phenophase of Populus tomentosa in spring and autumn from 17 phenological observation stations in Inner Mongolia, the change trend of the phenophase of P. tomentosa in spring and autumn was studied, and its relations to climate warming were analyzed. The models for predicting the date change of P. tomentosa first flowering and defoliating were constructed by stepwise regression method. It was shown that from 1982 to 2006, the air temperature in study area was increased, and the date of first flowering and defoliating of P. tomentosa was advanced and postponed, respectively. The first flowering of P. tomentosa was negatively related to the air temperature in spring and winter, and the main affecting factor was the air temperature from March to April; while the first defoliating of P. tomentosa was positively related to the air temperature in autumn, and the main affecting factor was the air temperature from August to October. According to the national assessment report on climate change, the air temperature in Inner Mongolia in spring and autumn would be raised by 1.5 degrees C-5.4 degrees C and 1.2 degrees C-4.4 degrees C, and the first flowering and defoliating of P. tomentosa would advance 3.9-17.8 days and postpone 3.0-12.4 days, respectively.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19565756?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Barakat, Abdelali</style></author><author><style face="normal" font="default" size="100%">Bagniewska-Zadworna, Agnieszka</style></author><author><style face="normal" font="default" size="100%">Choi, Alex</style></author><author><style face="normal" font="default" size="100%">Plakkat, Urmila</style></author><author><style face="normal" font="default" size="100%">DiLoreto, Denis S</style></author><author><style face="normal" font="default" size="100%">Yellanki, Priyadarshini</style></author><author><style face="normal" font="default" size="100%">Carlson, John E</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The cinnamyl alcohol dehydrogenase gene family in Populus: phylogeny, organization, and expression.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC plant biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Plant Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">26</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Lignin is a phenolic heteropolymer in secondary cell walls that plays a major role in the development of plants and their defense against pathogens. The biosynthesis of monolignols, which represent the main component of lignin involves many enzymes. The cinnamyl alcohol dehydrogenase (CAD) is a key enzyme in lignin biosynthesis as it catalyzes the final step in the synthesis of monolignols. The CAD gene family has been studied in Arabidopsis thaliana, Oryza sativa and partially in Populus. This is the first comprehensive study on the CAD gene family in woody plants including genome organization, gene structure, phylogeny across land plant lineages, and expression profiling in Populus.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19267902?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Harding, Scott A</style></author><author><style face="normal" font="default" size="100%">Jarvie, Michelle M</style></author><author><style face="normal" font="default" size="100%">Lindroth, Richard L</style></author><author><style face="normal" font="default" size="100%">Tsai, Chung-Jui</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A comparative analysis of phenylpropanoid metabolism, N utilization, and carbon partitioning in fast- and slow-growing Populus hybrid clones.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of experimental botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Exp. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">60</style></volume><pages><style face="normal" font="default" size="100%">3443-52</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The biosynthetic costs of phenylpropanoid-derived condensed tannins (CTs) and phenolic glycosides (PGs) are substantial. However, despite reports of negative correlations between leaf phenolic content and growth of Populus, it remains unclear whether or how foliar biosynthesis of CT/PG interferes with tree growth. A comparison was made of carbon partitioning and N content in developmentally staged leaves, stems, and roots of two closely related Populus hybrid genotypes. The genotypes were selected as two of the most phytochemically divergent from a series of seven previously analysed clones that exhibit a range of height growth rates and foliar amino acid, CT, and PG concentrations. The objective was to analyse the relationship between leaf phenolic content and plant growth, using whole-plant carbon partitioning and N distribution data from the two divergent clones. Total N as a percentage of tissue dry mass was comparatively low, and CT and PG accrual comparatively high in leaves of the slow-growing clone. Phenylpropanoid accrual and N content were comparatively high in stems of the slow-growing clone. Carbon partitioning within phenylpropanoid and carbohydrate networks in developing stems differed sharply between clones. The results did not support the idea that foliar production of phenylpropanoid defence chemicals was the primary cause of reduced plant growth in the slow-growing clone. The findings are discussed in the context of metabolic mechanism(s) which may contribute to reduced N delivery from roots to leaves, thereby compromising tree growth and promoting leaf phenolic accrual in the slow-growing clone.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19516073?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Liberloo, Marion</style></author><author><style face="normal" font="default" size="100%">Lukac, Martin</style></author><author><style face="normal" font="default" size="100%">Calfapietra, Carlo</style></author><author><style face="normal" font="default" size="100%">Hoosbeek, Marcel R</style></author><author><style face="normal" font="default" size="100%">Gielen, Birgit</style></author><author><style face="normal" font="default" size="100%">Miglietta, Franco</style></author><author><style face="normal" font="default" size="100%">Scarascia-Mugnozza, Giuseppe E</style></author><author><style face="normal" font="default" size="100%">Ceulemans, Reinhart</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Coppicing shifts CO2 stimulation of poplar productivity to above-ground pools: a synthesis of leaf to stand level results from the POP/EUROFACE experiment.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">182</style></volume><pages><style face="normal" font="default" size="100%">331-46</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A poplar short rotation coppice (SRC) grown for the production of bioenergy can combine carbon (C) storage with fossil fuel substitution. Here, we summarize the responses of a poplar (Populus) plantation to 6 yr of free air CO(2) enrichment (POP/EUROFACE consisting of two rotation cycles). We show that a poplar plantation growing in nonlimiting light, nutrient and water conditions will significantly increase its productivity in elevated CO(2) concentrations ([CO(2)]). Increased biomass yield resulted from an early growth enhancement and photosynthesis did not acclimate to elevated [CO(2)]. Sufficient nutrient availability, increased nitrogen use efficiency (NUE) and the large sink capacity of poplars contributed to the sustained increase in C uptake over 6 yr. Additional C taken up in high [CO(2)] was mainly invested into woody biomass pools. Coppicing increased yield by 66% and partly shifted the extra C uptake in elevated [CO(2)] to above-ground pools, as fine root biomass declined and its [CO(2)] stimulation disappeared. Mineral soil C increased equally in ambient and elevated [CO(2)] during the 6 yr experiment. However, elevated [CO(2)] increased the stabilization of C in the mineral soil. Increased productivity of a poplar SRC in elevated [CO(2)] may allow shorter rotation cycles, enhancing the viability of SRC for biofuel production.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19207687?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Islam-Faridi, M N</style></author><author><style face="normal" font="default" size="100%">Nelson, C D</style></author><author><style face="normal" font="default" size="100%">DiFazio, S P</style></author><author><style face="normal" font="default" size="100%">Gunter, L E</style></author><author><style face="normal" font="default" size="100%">Tuskan, G A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Cytogenetic analysis of Populus trichocarpa--ribosomal DNA, telomere repeat sequence, and marker-selected BACs.</style></title><secondary-title><style face="normal" font="default" size="100%">Cytogenetic and genome research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Cytogenet. Genome Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">125</style></volume><pages><style face="normal" font="default" size="100%">74-80</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The 18S-28S rDNA and 5S rDNA loci in Populus trichocarpa were localized using fluorescent in situ hybridization (FISH). Two 18S-28S rDNA sites and one 5S rDNA site were identified and located at the ends of 3 different chromosomes. FISH signals from the Arabidopsis-type telomere repeat sequence were observed at the distal ends of each chromosome. Six BAC clones selected from 2 linkage groups based on genome sequence assembly (LG-I and LG-VI) were localized on 2 chromosomes, as expected. BACs from LG-I hybridized to the longest chromosome in the complement. All BAC positions were found to be concordant with sequence assembly positions. BAC-FISH will be useful for delineating each of the Populus trichocarpa chromosomes and improving the sequence assembly of this model angiosperm tree species.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19617699?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Cabrera, Antonio</style></author><author><style face="normal" font="default" size="100%">Kozik, Alex</style></author><author><style face="normal" font="default" size="100%">Howad, Werner</style></author><author><style face="normal" font="default" size="100%">Arus, Pere</style></author><author><style face="normal" font="default" size="100%">Iezzoni, Amy F</style></author><author><style face="normal" font="default" size="100%">van der Knaap, Esther</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Development and bin mapping of a Rosaceae Conserved Ortholog Set (COS) of markers.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC genomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">10</style></volume><pages><style face="normal" font="default" size="100%">562</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Detailed comparative genome analyses within the economically important Rosaceae family have not been conducted. This is largely due to the lack of conserved gene-based molecular markers that are transferable among the important crop genera within the family [e.g. Malus (apple), Fragaria (strawberry), and Prunus (peach, cherry, apricot and almond)]. The lack of molecular markers and comparative whole genome sequence analysis for this family severely hampers crop improvement efforts as well as QTL confirmation and validation studies.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19943965?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wang, Minjie</style></author><author><style face="normal" font="default" size="100%">Qi, Xiaoli</style></author><author><style face="normal" font="default" size="100%">Zhao, Shutang</style></author><author><style face="normal" font="default" size="100%">Zhang, Shougong</style></author><author><style face="normal" font="default" size="100%">Lu, Meng-Zhu</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Dynamic changes in transcripts during regeneration of the secondary vascular system in Populus tomentosa Carr. revealed by cDNA microarrays.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC genomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">10</style></volume><pages><style face="normal" font="default" size="100%">215</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Wood is the end product of secondary vascular system development, which begins from the cambium. The wood formation process includes four major stages: cell expansion, secondary wall biosynthesis, lignification, and programmed cell death. Transcriptional profiling is a rapid way to screen for genes involved in these stages and their transitions, providing the basis for understanding the molecular mechanisms that control this process.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19426563?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gazzani, Silvia</style></author><author><style face="normal" font="default" size="100%">Li, Mingai</style></author><author><style face="normal" font="default" size="100%">Maistri, Silvia</style></author><author><style face="normal" font="default" size="100%">Scarponi, Eliana</style></author><author><style face="normal" font="default" size="100%">Graziola, Michele</style></author><author><style face="normal" font="default" size="100%">Barbaro, Enrico</style></author><author><style face="normal" font="default" size="100%">Wunder, Jörg</style></author><author><style face="normal" font="default" size="100%">Furini, Antonella</style></author><author><style face="normal" font="default" size="100%">Saedler, Heinz</style></author><author><style face="normal" font="default" size="100%">Varotto, Claudio</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Evolution of MIR168 paralogs in Brassicaceae.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC evolutionary biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Evol. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">62</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In plants, expression of ARGONAUTE1 (AGO1), the catalytic subunit of the RNA-Induced Silencing Complex responsible for post-transcriptional gene silencing, is controlled through a feedback loop involving the miR168 microRNA. This complex auto-regulatory loop, composed of miR168-guided AGO1-catalyzed cleavage of AGO1 mRNA and AGO1-mediated stabilization of miR168, was shown to ensure the maintenance of AGO1 homeostasis that is pivotal for the correct functioning of the miRNA pathway.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19309501?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Levée, Valérie</style></author><author><style face="normal" font="default" size="100%">Major, Ian</style></author><author><style face="normal" font="default" size="100%">Levasseur, Caroline</style></author><author><style face="normal" font="default" size="100%">Tremblay, Laurence</style></author><author><style face="normal" font="default" size="100%">MacKay, John</style></author><author><style face="normal" font="default" size="100%">Séguin, Armand</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Expression profiling and functional analysis of Populus WRKY23 reveals a regulatory role in defense.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">184</style></volume><pages><style face="normal" font="default" size="100%">48-70</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">WRKY transcription factors are key regulators that activate and fine-tune stress responses, including defense responses against pathogens. We isolated a poplar (Populus tremulaxPopulus alba) cDNA sequence, PtWRKY23, that encodes the ortholog of Arabidopsis WRKY23 and present the functional analysis of WRKY23, with emphasis on its potential role in resistance to rust infection. To investigate the function of PtWRKY23, we examined PtWRKY23 expression after stress treatments by qRT-PCR and generated PtWRKY23-misexpressing plants. Transgenic plants were assessed for resistance to Melampsora rust and were analyzed using the poplar Affymetrix GeneChip and histological techniques to study the consequences of PtWRKY23 misexpression. PtWRKY23 is rapidly induced by Melampsora infection and elicitor treatments and poplars overexpressing and underexpressing PtWRKY23 were both more susceptible to Melampsora infection than wild type. Transcriptome analysis of PtWRKY23 overexpressors revealed a significant overlap with the Melampsora-infection response. Transcriptome analysis also suggests that PtWRKY23 affects redox homeostasis and cell wall-related metabolism, which was confirmed by analyses that showed that PtWRKY23-misexpressing plants have altered peroxidase activity, apparent H(2)O(2) accumulation and lignin deposition. Our results show that PtWRKY23 affects resistance to Melampsora infection and that this may be caused by deregulation of genes that disrupt redox homeostasis and cell wall metabolism.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19674332?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rae, Anne M</style></author><author><style face="normal" font="default" size="100%">Street, Nathaniel Robert</style></author><author><style face="normal" font="default" size="100%">Robinson, Kathryn Megan</style></author><author><style face="normal" font="default" size="100%">Harris, Nicole</style></author><author><style face="normal" font="default" size="100%">Taylor, Gail</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Five QTL hotspots for yield in short rotation coppice bioenergy poplar: the Poplar Biomass Loci.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC plant biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Plant Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">23</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Concern over land use for non-food bioenergy crops requires breeding programmes that focus on producing biomass on the minimum amount of land that is economically-viable. To achieve this, the maximum potential yield per hectare is a key target for improvement. For long lived tree species, such as poplar, this requires an understanding of the traits that contribute to biomass production and their genetic control. An important aspect of this for long lived plants is an understanding of genetic interactions at different developmental stages, i.e. how genes or genetic regions impact on yield over time.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19245718?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Li, Wan-Feng</style></author><author><style face="normal" font="default" size="100%">Ding, Qi</style></author><author><style face="normal" font="default" size="100%">Chen, Jia-Jia</style></author><author><style face="normal" font="default" size="100%">Cui, Ke-Ming</style></author><author><style face="normal" font="default" size="100%">He, Xin-Qiang</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Induction of PtoCDKB and PtoCYCB transcription by temperature during cambium reactivation in Populus tomentosa Carr.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of experimental botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Exp. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">60</style></volume><pages><style face="normal" font="default" size="100%">2621-30</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Cell cycle progression requires interaction between cyclin-dependent kinase B (CDKB) and cyclin B (CYCB). The seasonal expression patterns of the CDKB and CYCB homologues from Populus tomentosa Carr. were investigated, and effects of temperature and exogenous indole-3-acetic acid (IAA) on their expression were further studied in water culture experiments. Based on the differential responses of dormant cambium cells to exogenous IAA, four stages of cambium dormancy were confirmed for P. tomentosa: quiescence 1 (Q1), rest, quiescence 2-1 (Q2-1), and quiescence 2-2 (Q2-2). PtoCDKB and PtoCYCB transcripts were strongly expressed in the active phases, weakly in Q1, and almost undetectable from rest until late Q2-2. Climatic data analysis showed a correlation between daily air temperature and PtoCDKB and PtoCYCB expression patterns. Water culture experiments with temperature treatment further showed that a low temperature (4 degrees C) kept PtoCDKB and PtoCYCB transcripts at undetectable levels, while a warm temperature (25 degrees C) induced their expression in the cambium region. Meanwhile, water culture experiments with exogenous IAA treatment showed that induction of PtoCDKB and PtoCYCB transcription was independent of exogenous IAA. The results suggest that, in deciduous hardwood P. tomentosa growing in a temperate zone, the temperature in early spring is a vital environmental factor for cambium reactivation. The increasing temperature in early spring may induce CDKB and CYCB homologue transcription in the cambium region, which is necessary for cambium cell division.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19414499?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Cocozza, Claudia</style></author><author><style face="normal" font="default" size="100%">Lasserre, Bruno</style></author><author><style face="normal" font="default" size="100%">Giovannelli, Alessio</style></author><author><style face="normal" font="default" size="100%">Castro, Gaetano</style></author><author><style face="normal" font="default" size="100%">Fragnelli, Giuseppe</style></author><author><style face="normal" font="default" size="100%">Tognetti, Roberto</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Low temperature induces different cold sensitivity in two poplar clones (Populus x canadensis Monch 'I-214' and P. deltoides Marsh. 'Dvina').</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of experimental botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Exp. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">60</style></volume><pages><style face="normal" font="default" size="100%">3655-64</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Changes of stem diameter were continuously monitored during winter in two field-grown poplar clones, using automatic point dendrometers. The objective of this study was to find an analytical solution to seasonal synchronization of stem diameter oscillations and low air temperatures. The study identified to what extent and with what frequency low air temperature induced stem diameter variation in 'Dvina' (P. deltoides) and 'I-214' (Populus x canadensis) poplar clones, after exposure to summer drought. The patterns of reversible stem shrinkage were related to the cycles of low air temperature. Hourly and daily evidence showed that 'I-214' was more sensitive to low air temperatures than 'Dvina'. The analysis of raw data and graphic details implemented with the study of derivative tests allowed an increase in the general sensitivity of the investigation applied to describe the response of poplar clones to environmental conditions. Given these diameter fluctuation patterns, automatic point dendrometers were confirmed to be a reliable non-invasive method for testing the sensitivity of diameter variation to cold temperature. Variation in rate and duration of daily stem shrinkage in response to low air temperature in winter appeared to occur independently of the effects of water deficit suffered by plants the previous summer.</style></abstract><issue><style face="normal" font="default" size="100%">13</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19567480?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Breen, Amy L</style></author><author><style face="normal" font="default" size="100%">Glenn, Elise</style></author><author><style face="normal" font="default" size="100%">Yeager, Adam</style></author><author><style face="normal" font="default" size="100%">Olson, Matthew S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Nucleotide diversity among natural populations of a North American poplar (Populus balsamifera, Salicaceae).</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">182</style></volume><pages><style face="normal" font="default" size="100%">763-73</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Poplars (Populus spp.) comprise an important component of circumpolar boreal forest ecosystems and are the model species for tree genomics. In this study, we surveyed genetic variation and population differentiation in three nuclear genes among populations of balsam poplar (Populus balsamifera) in North America. We examined nucleotide sequence variation in alcohol dehydrogenase 1 (Adh1) and glyceraldehyde 3-phosphate dehydrogenase (G3pdh), two well-studied nuclear loci in plants, and abscisic acid insensitivity 1B (ABI1B), a locus coincident with timing of seasonal dormancy in quantitative trait locus (QTL) studies of hybrid poplars. We compared estimates of baseline population genetic parameters for these loci with those obtained in studies of other poplar species, particularly European aspen (Populus tremula). Average pairwise nucleotide diversity (pi(tot) = 0.00216-0.00353) was equivalent to that in Populus trichocarpa, but markedly less than that in P. tremula. Elevated levels of population structure were observed in ABI1B between the northern and southern regions (F(CT) = 0.184, P &lt; 0.001) and among populations (F(ST) = 0.256, P &lt; 0.001). These results suggest that geographic or taxonomic factors are important for understanding patterns of variation throughout the genus Populus. Our findings have the potential to aid in the design of sampling regimes for conservation and breeding stock and contribute to historical inferences regarding the factors that shaped the genetic diversity of boreal plant species.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19228296?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sutela, Suvi</style></author><author><style face="normal" font="default" size="100%">Niemi, Karoliina</style></author><author><style face="normal" font="default" size="100%">Edesi, Jaanika</style></author><author><style face="normal" font="default" size="100%">Laakso, Tapio</style></author><author><style face="normal" font="default" size="100%">Saranpää, Pekka</style></author><author><style face="normal" font="default" size="100%">Vuosku, Jaana</style></author><author><style face="normal" font="default" size="100%">Mäkelä, Riina</style></author><author><style face="normal" font="default" size="100%">Tiimonen, Heidi</style></author><author><style face="normal" font="default" size="100%">Chiang, Vincent L</style></author><author><style face="normal" font="default" size="100%">Koskimäki, Janne</style></author><author><style face="normal" font="default" size="100%">Suorsa, Marja</style></author><author><style face="normal" font="default" size="100%">Julkunen-Tiitto, Riitta</style></author><author><style face="normal" font="default" size="100%">Häggman, Hely</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Phenolic compounds in ectomycorrhizal interaction of lignin modified silver birch.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC plant biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Plant Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">124</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The monolignol biosynthetic pathway interconnects with the biosynthesis of other secondary phenolic metabolites, such as cinnamic acid derivatives, flavonoids and condensed tannins. The objective of this study is to evaluate whether genetic modification of the monolignol pathway in silver birch (Betula pendula Roth.) would alter the metabolism of these phenolic compounds and how such alterations, if exist, would affect the ectomycorrhizal symbiosis.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19788757?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhou, Fengfeng</style></author><author><style face="normal" font="default" size="100%">Xu, Ying</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">RepPop: a database for repetitive elements in Populus trichocarpa.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC genomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">10</style></volume><pages><style face="normal" font="default" size="100%">14</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Populus trichocarpa is the first tree genome to be completed, and its whole genome is currently being assembled. No functional annotation about the repetitive elements in the Populus trichocarpa genome is currently available.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19134208?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Aubrey, Doug P</style></author><author><style face="normal" font="default" size="100%">Teskey, Robert O</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Root-derived CO(2) efflux via xylem stream rivals soil CO(2) efflux.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">184</style></volume><pages><style face="normal" font="default" size="100%">35-40</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Respiration consumes a large portion of annual gross primary productivity in forest ecosystems and is dominated by belowground metabolism. Here, we present evidence of a previously unaccounted for internal CO(2) flux of large magnitude from tree roots through stems. If this pattern is shown to persist over time and in other forests, it suggests that belowground respiration has been grossly underestimated. Using an experimental Populus deltoides plantation as a model system, we tested the hypothesis that a substantial portion of the CO(2) released from belowground autotrophic respiration remains within tree root systems and is transported aboveground through the xylem stream rather than diffusing into the soil atmosphere. On a daily basis, the amount of CO(2) that moved upward from the root system into the stem via the xylem stream (0.26 mol CO(2) m(-2) d(-1)) rivalled that which diffused from the soil surface to the atmosphere (0.27 mol CO(2) m(-2) d(-1)). We estimated that twice the amount of CO(2) derived from belowground autotrophic respiration entered the xylem stream as diffused into the soil environment. Our observations indicate that belowground autotrophic respiration consumes substantially more carbohydrates than previously recognized and challenge the paradigm that all root-respired CO(2) diffuses into the soil atmosphere.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19674328?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Jung, Sook</style></author><author><style face="normal" font="default" size="100%">Jiwan, Derick</style></author><author><style face="normal" font="default" size="100%">Cho, Ilhyung</style></author><author><style face="normal" font="default" size="100%">Lee, Taein</style></author><author><style face="normal" font="default" size="100%">Abbott, Albert</style></author><author><style face="normal" font="default" size="100%">Sosinski, Bryon</style></author><author><style face="normal" font="default" size="100%">Main, Dorrie</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Synteny of Prunus and other model plant species.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC genomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">10</style></volume><pages><style face="normal" font="default" size="100%">76</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Fragmentary conservation of synteny has been reported between map-anchored Prunus sequences and Arabidopsis. With the availability of genome sequence for fellow rosid I members Populus and Medicago, we analyzed the synteny between Prunus and the three model genomes. Eight Prunus BAC sequences and map-anchored Prunus sequences were used in the comparison.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19208249?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sokolova, G B</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Clinical and experimental pharmacology as a basis for the strategy and tactics of tuberculosis chemotherapy (1970-2008)].</style></title><secondary-title><style face="normal" font="default" size="100%">Problemy tuberkuleza i bolezneĭ legkikh</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Probl Tuberk Bolezn Legk</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">22-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099385?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Timasheva, G V</style></author><author><style face="normal" font="default" size="100%">Valeeva, O V</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Diagnostic value of biochemic and hematologic changes in petrochemical industry workers].</style></title><secondary-title><style face="normal" font="default" size="100%">Meditsina truda i promyshlennaia ekologiia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Med Tr Prom Ekol</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">20-3</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Thorough biochemic and hematologic studies covered workers engaged into various petrochemical industry branches. Lipid metabolism changes were seen in most examinees, the authors determined the most informative laboratory values to diagnose preclinical health disorders in the workers.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099389?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Il'ina, T Ia</style></author><author><style face="normal" font="default" size="100%">Zhangireev, A A</style></author><author><style face="normal" font="default" size="100%">Sidorenko, O A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Efficiency of treatment for recurrent tuberculosis and its influencing factors].</style></title><secondary-title><style face="normal" font="default" size="100%">Problemy tuberkuleza i bolezneĭ legkikh</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Probl Tuberk Bolezn Legk</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">38-42</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The efficiency of category II DOTS chemotherapy was studied in 353 patients with recurrent tuberculosis. The latter was verified by a positive sputum smear test in 232 of them and this test was negative in 121. A control group consisted of 79 first detected patients. The results of the treatment for recurrences were substantially worse than those in new-onset tuberculosis. These have recently improved. Mycobacterium tuberculosis resistance to drugs was responsible for failing therapy. The worse results were obtained when the disease was multidrug resistant. Other reasons, social risk factors in particular, leading to incompliance lowered therapeutic effectiveness.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099386?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bakirov, A B</style></author><author><style face="normal" font="default" size="100%">Gimranova, G G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Main results of scientific researches in oil industry].</style></title><secondary-title><style face="normal" font="default" size="100%">Meditsina truda i promyshlennaia ekologiia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Med Tr Prom Ekol</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">1-5</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Clinical and hygienic research was carried out in major oil extracting, oil processing and petrochemical enterpirses. Complex of industrial hazards results in occupational diseases of mild and medium severity, in increase of occupationally mediated diseases. The article covers sanitary and epidemiologic evaluation of oil processing and petrochemical products, technical documentation certificates for these products are obtained.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099388?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Mukhtarov, D Z</style></author><author><style face="normal" font="default" size="100%">Sultanova, R A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[The specific features of the clinical course of tuberculosis and enhancement of its treatment efficiency in fertile-age women with iron-deficiency anemia].</style></title><secondary-title><style face="normal" font="default" size="100%">Problemy tuberkuleza i bolezneĭ legkikh</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Probl Tuberk Bolezn Legk</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">45-50</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">One hundred and twenty-three female patients aged 16 to 49 years with pulmonary tuberculosis were examined and followed up. Of them, 83 (67.5%) patients in whom tuberculosis had occurred and run in the presence of iron-deficiency anemia (IDA) made up a study group and 40 (32.5%) patients in whom tuberculosis had occurred without IDA formed a control group. In the women from the study group, the clinical manifestations of the disease had its own peculiarities: a less pronounced temperature reaction, meager expectoration, severe signs of hypoxia (dyspnea), and chest pain and 97% were found to have abnormally shaped red blood cells (poikilocytosis). Inclusion of Tardiferon into complex treatment aids in enhancing the efficiency of treatment for tuberculosis in the presence of IDA, promoting to a greater extent the regression of the clinical manifestations of the disease and the achievement of abacillation than cicatrization.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/20099387?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Waters, Elizabeth R</style></author><author><style face="normal" font="default" size="100%">Aevermann, Brian D</style></author><author><style face="normal" font="default" size="100%">Sanders-Reed, Zipporah</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Comparative analysis of the small heat shock proteins in three angiosperm genomes identifies new subfamilies and reveals diverse evolutionary patterns.</style></title><secondary-title><style face="normal" font="default" size="100%">Cell stress &amp; chaperones</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Cell Stress Chaperones</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Summer</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">13</style></volume><pages><style face="normal" font="default" size="100%">127-42</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The small heat shock proteins (sHSPs) are a diverse family of molecular chaperones. It is well established that these proteins are crucial components of the plant heat shock response. They also have important roles in other stress responses and in normal development. We have conducted a comparative sequence analysis of the sHSPs in three complete angiosperms genomes: Arabidopsis thaliana, Populus trichocarpa, and Oryza sativa. Our phylogenetic analysis has identified four additional plant sHSP subfamilies and thus has increased the number of plant sHSP subfamilies from 7 to 11. We have also identified a number of novel sHSP genes in each genome that lack close homologs in other genomes. Using publicly available gene expression data and predicted secondary structures, we have determined that the sHSPs in plants are far more diverse in sequence, expression profile, and in structure than had been previously known. Some of the newly identified subfamilies are not stress regulated, may not possess the highly conserved large oligomer structure, and may not even function as molecular chaperones. We found no consistent evolutionary patterns across the three species studied. For example, gene conversion was found among the sHSPs in O. sativa but not in A. thaliana or P. trichocarpa. Among the three species, P. trichocarpa had the most sHSPs. This was due to an expansion of the cytosolic I sHSPs that was not seen in the other two species. Our analysis indicates that the sHSPs are a dynamic protein family in angiosperms with unexpected levels of diversity.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18759000?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ozer, Serkan</style></author><author><style face="normal" font="default" size="100%">Irmak, M Akif</style></author><author><style face="normal" font="default" size="100%">Yilmaz, Hasan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Determination of roadside noise reduction effectiveness of Pinus sylvestris L. and Populus nigra L. in Erzurum, Turkey.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental monitoring and assessment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ Monit Assess</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">144</style></volume><pages><style face="normal" font="default" size="100%">191-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">This study was carried out to determine the noise-reduction effectiveness of the Pinus sylvestris L. and Populus nigra L. trees along the E-80 State highway in Erzurum-Turkey. Noise values were taken at three measurement points; open (without trees and taken as control), the urban forests of pure P. sylvestris L. and P. nigra L. areas, and at four different distances; 0 (near the noise source), 25, 50 and 75 m from the noise source. At the distance of 25 m from the source, the noise value was 78.5 dB(A) in the control area, which was reduced 75.5 dB(A) and 69.2 dB(A) in the P. nigra L. and P. sylvestris L. areas, with the reduction rates of 24.7 and 31% compared to the control, respectively. This value was 69.6, 67.1 and 64.3 at the distance of 50 m and 64.9, 62.5 and 59.2 at 75 m for the naked, P. nigra L. and P. sylvestris L. areas, respectively. From the results of the study, it was suggested that for the noise pollution from the traffic flow on the roads, in especially the big cities, noise reduction zones with suitable width and plant species should be formed along the main arteries of the cities.</style></abstract><issue><style face="normal" font="default" size="100%">1-3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17957489?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Krpata, Doris</style></author><author><style face="normal" font="default" size="100%">Peintner, Ursula</style></author><author><style face="normal" font="default" size="100%">Langer, Ingrid</style></author><author><style face="normal" font="default" size="100%">Fitz, Walter J</style></author><author><style face="normal" font="default" size="100%">Schweiger, Peter</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Ectomycorrhizal communities associated with Populus tremula growing on a heavy metal contaminated site.</style></title><secondary-title><style face="normal" font="default" size="100%">Mycological research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mycol. Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">112</style></volume><pages><style face="normal" font="default" size="100%">1069-79</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">European aspen is one of the most widely distributed trees in Central Europe and is a typical early colonizer of poor and disturbed soils. However, little is known about ectomycorrhizal (ECM) fungi in these ecosystems. We examined the ECM community of European aspen growing on a heavily contaminated site in southern Austria by analysing ECM roots, sorting them into morphotypes, subjecting them to DNA extraction, PCR, and DNA sequencing. ECM root symbionts were sampled two times in 2004. During this time, the below-ground community structure was relatively stable; we found no evidence of taxa adapted to summer or autumn conditions and only two species varied widely in occurrence between soil horizons. The ECM fungal community was diverse (54 species), rich in Basidiomycota (43 species), and dominated by Cenococcum geophilum and fungi with corticoid basidiomes (e.g. Thelephoraceae).</style></abstract><issue><style face="normal" font="default" size="100%">Pt 9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18692376?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Oliver, Kathryn L</style></author><author><style face="normal" font="default" size="100%">Hamelin, Richard C</style></author><author><style face="normal" font="default" size="100%">Hintz, William E</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Effects of transgenic hybrid aspen overexpressing polyphenol oxidase on rhizosphere diversity.</style></title><secondary-title><style face="normal" font="default" size="100%">Applied and environmental microbiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Appl. Environ. Microbiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">74</style></volume><pages><style face="normal" font="default" size="100%">5340-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">This study assessed the potential effects of transgenic aspen overexpressing a polyphenol oxidase gene on diversity in rhizosphere communities. Cultivation-independent methods were used to better delineate bacterial and fungal populations associated with transgenic and nontransgenic trees. Gene libraries for the bacterial component of the rhizosphere were established using 16S rRNA and chaperonin-60 (CPN-60) gene sequences, while the fungal community was characterized using 18S rRNA gene sequences. The 16S rRNA gene libraries were dominated by alphaproteobacterial sequences, while the CPN-60 gene libraries were dominated by members of the Bacteroidetes/Chlorobi group. In both the CPN-60 and 16S rRNA libraries, there were differences in only minor components of the bacterial community between transgenic and unmodified trees, and no significant differences in species diversity were observed. Compared to the bacterial gene libraries, greater coverage of the underlying population was achieved with the fungal 18S rRNA libraries. Members of the Zygomycota, Chytridiomycota, Ascomycota, and Basidiomycota were recovered from both libraries. The dominant groups of fungi associated with each tree type were very similar, although there were some qualitative differences in the recovery of less-abundant fungi, likely as a result of the underlying heterogeneity of the fungal population. The methods employed revealed only minor differences between the bacterial and fungal communities associated with transgenic and unmodified trees.</style></abstract><issue><style face="normal" font="default" size="100%">17</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18552195?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Barrès, Benoît</style></author><author><style face="normal" font="default" size="100%">Halkett, Fabien</style></author><author><style face="normal" font="default" size="100%">Dutech, Cyril</style></author><author><style face="normal" font="default" size="100%">Andrieux, Axelle</style></author><author><style face="normal" font="default" size="100%">Pinon, Jean</style></author><author><style face="normal" font="default" size="100%">Frey, Pascal</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genetic structure of the poplar rust fungus Melampsora larici-populina: evidence for isolation by distance in Europe and recent founder effects overseas.</style></title><secondary-title><style face="normal" font="default" size="100%">Infection, genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Infect. Genet. Evol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">8</style></volume><pages><style face="normal" font="default" size="100%">577-87</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Dispersal has a great impact on the genetic structure of populations, but remains difficult to estimate by direct measures. In particular, gradual and stochastic dispersal are often difficult to assess and to distinguish, although they have different evolutionary consequences. Plant pathogens, especially rust fungi, are suspected to display both dispersal modes, though on different spatial scales. In this study, we inferred dispersal capacities of the poplar rust fungus Melampsora larici-populina by examining the genetic diversity and structure of 13 populations from eight European and two overseas countries in the Northern hemisphere. M. larici-populina was sampled from both cultivated hybrid poplars and on the wild host, Populus nigra. The populations were analyzed with 11 microsatellite and 8 virulence markers. Although isolates displayed different virulence profiles according to the host plant, neutral markers revealed little population differentiation with respect to the type of host. This suggests an absence of reproductive isolation between populations sampled from cultivated and wild poplars. Conversely, studying the relationship between geographic and genetic structure allowed us to distinguish between isolation by distance (IBD) patterns and long distance dispersal (LDD) events. The European populations exhibited a significant IBD pattern, suggesting a regular and gradual dispersal of the pathogen over this spatial scale. Nonetheless, the genetic differentiation between these populations was low, suggesting an important gene flow on a continental scale. The two overseas populations from Iceland and Canada were shown to result from rare LDD events, and exhibited signatures of strong founder effects. Furthermore, the high genetic differentiation between both populations suggested that these two recent introductions were independent. This study illustrated how the proper use of population genetics methods can enable contrasted dispersal modes to be revealed.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18499532?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Dillen, Sophie Y</style></author><author><style face="normal" font="default" size="100%">Marron, Nicolas</style></author><author><style face="normal" font="default" size="100%">Koch, Barbra</style></author><author><style face="normal" font="default" size="100%">Ceulemans, Reinhart</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genetic variation of stomatal traits and carbon isotope discrimination in two hybrid poplar families (Populus deltoides 'S9-2' x P. nigra 'Ghoy' and P. deltoides 'S9-2' x P. trichocarpa 'V24').</style></title><secondary-title><style face="normal" font="default" size="100%">Annals of botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ann. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">102</style></volume><pages><style face="normal" font="default" size="100%">399-407</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Stomata play an important role in both the CO(2) assimilation and water relations of trees. Therefore, stomatal traits have been suggested as criteria for selection of clones or genotypes which are more productive and have larger water-use efficiency (WUE) than others. However, the relationships between plant growth, WUE and stomatal traits are still unclear depending on plant material (genus, species, families, genotypes) and, more precisely, on the strength of the relationships between the plants. In this study, the correlations between these three traits categories, i.e. plant growth, WUE and stomatal traits, were compared in two related poplar families.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18587131?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Teichmann, Thomas</style></author><author><style face="normal" font="default" size="100%">Bolu-Arianto, Waode Hamsinah</style></author><author><style face="normal" font="default" size="100%">Olbrich, Andrea</style></author><author><style face="normal" font="default" size="100%">Langenfeld-Heyser, Rosemarie</style></author><author><style face="normal" font="default" size="100%">Göbel, Cornelia</style></author><author><style face="normal" font="default" size="100%">Grzeganek, Peter</style></author><author><style face="normal" font="default" size="100%">Feussner, Ivo</style></author><author><style face="normal" font="default" size="100%">Hänsch, Robert</style></author><author><style face="normal" font="default" size="100%">Polle, Andrea</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">GH3::GUS reflects cell-specific developmental patterns and stress-induced changes in wood anatomy in the poplar stem.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">1305-15</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">GH3 genes related to the auxin-inducible Glycine max (L.) Merr. GmGH3 gene encode enzymes that conjugate amino acids to auxin. To investigate the role of GH3 enzymes in stress responses and normal wood development, Populus x canescens (Ait.) was transformed with the promoter-reporter construct GH3::GUS containing a GH3 promoter and the 5' UTR from soybean. beta-Glucuronidase (GUS) activity was present in the vascular tissues of leaves and in developing lateral roots and was inducible in silent tissues by external auxin application. A decrease in GUS activity from the stem apex to the bottom corresponded to decreases in auxin concentrations in these tissues. High auxin concentration and high GH3::GUS activity were present in the pith tissue, which may provide storage for auxin compounds. GH3 reporter was active in ray cells, paratracheal parenchyma cells, maturing vessels and in cells surrounding maturing phloem fibers but not in the cambium and immature phloem, despite high auxin concentrations in the latter tissues. However, the GH3 promoter in these tissues became active when the plants were exposed to abiotic stresses, like bending or salinity, causing changes in wood anatomy. We suggest that adjustment of the internal auxin balance in wood in response to environmental cues involves GH3 auxin conjugate synthases.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18595842?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Langer, Ingrid</style></author><author><style face="normal" font="default" size="100%">Krpata, Doris</style></author><author><style face="normal" font="default" size="100%">Peintner, Ursula</style></author><author><style face="normal" font="default" size="100%">Wenzel, Walter W</style></author><author><style face="normal" font="default" size="100%">Schweiger, Peter</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Media formulation influences in vitro ectomycorrhizal synthesis on the European aspen Populus tremula L.</style></title><secondary-title><style face="normal" font="default" size="100%">Mycorrhiza</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mycorrhiza</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">18</style></volume><pages><style face="normal" font="default" size="100%">297-307</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The effect of various media formulations on in vitro ectomycorrhizal synthesis of identified fungal strains with European aspen (Populus tremula L.) was tested in Petri dishes. Pre-grown seedlings were transferred to various nutrient media and inoculated with Paxillus involutus isolates using modified sandwich techniques. Mycorrhiza formation was evaluated macroscopically and further confirmed by microscopic examination of semi-thin sections for anatomical features of the mantle and the Hartig net. Standard media formulations did not support successful ectomycorrhiza formation because of either very poor plant survival (below 20%) or impaired fungal growth. The inclusion of micronutrients and vitamins in a Melin Norkrans (MMN)-based medium increased plant survival rate to above 60% and supported successful mycorrhizal synthesis. P. involutus isolates formed mycorrhizas with a characteristic Hartig net restricted to the epidermis. Mantle density and thickness varied depending on the isolate. In a follow-up experiment, the adapted medium supported successful ectomycorrhiza formation by various Laccaria and Hebeloma isolates. Our results show that an exogenous supply of vitamins and micronutrients in the medium was a prerequisite for successful mycorrhization of P. tremula in vitro in Petri dishes.</style></abstract><issue><style face="normal" font="default" size="100%">6-7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18594875?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ingvarsson, Pär K</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Multilocus patterns of nucleotide polymorphism and the demographic history of Populus tremula.</style></title><secondary-title><style face="normal" font="default" size="100%">Genetics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Genetics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">180</style></volume><pages><style face="normal" font="default" size="100%">329-40</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">I have studied nucleotide polymorphism and linkage disequilibrium using multilocus data from 77 fragments, with an average length of fragments of 550 bp, in the deciduous tree Populus tremula (Salicaceae). The frequency spectrum across loci showed a modest excess of mutations segregating at low frequency and a marked excess of high-frequency derived mutations at silent sites, relative to neutral expectations. These excesses were also seen at replacement sites, but were not so pronounced for high-frequency derived mutations. There was a marked excess of low-frequency mutations at replacement sites, likely indicating deleterious amino acid-changing mutations that segregate at low frequencies in P. tremula. I used approximate Bayesian computation (ABC) to evaluate a number of different demographic scenarios and to estimate parameters for the best-fitting model. The data were found to be consistent with a historical reduction in the effective population size of P. tremula through a bottleneck. The timing inferred for this bottleneck is largely consistent with geological data and with data from several other long-lived plant species. The results show that P. tremula harbors substantial levels of nucleotide polymorphism with the posterior mode of the scaled mutation rate, theta = 0.0177 across loci. The ABC analyses also provided an estimate of the scaled recombination rate that indicates that recombination rates in P. tremula are likely to be 2-10 times higher than the mutation rate. This study reinforces the notion that linkage disequilibrium is low and decays to negligible levels within a few hundred base pairs in P. tremula.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18716330?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Yang, Sihai</style></author><author><style face="normal" font="default" size="100%">Zhang, Xiaohui</style></author><author><style face="normal" font="default" size="100%">Yue, Jia-Xing</style></author><author><style face="normal" font="default" size="100%">Tian, Dacheng</style></author><author><style face="normal" font="default" size="100%">Chen, Jian-Qun</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Recent duplications dominate NBS-encoding gene expansion in two woody species.</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular genetics and genomics : MGG</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Genet. Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">280</style></volume><pages><style face="normal" font="default" size="100%">187-98</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Most disease resistance genes in plants encode NBS-LRR proteins. However, in woody species, little is known about the evolutionary history of these genes. Here, we identified 459 and 330 respective NBS-LRRs in grapevine and poplar genomes. We subsequently investigated protein motif composition, phylogenetic relationships and physical locations. We found significant excesses of recent duplications in perennial species, compared with those of annuals, represented by rice and Arabidopsis. Consequently, we observed higher nucleotide identity among paralogs and a higher percentage of NBS-encoding genes positioned in numerous clusters in the grapevine and poplar. These results suggested that recent tandem duplication played a major role in NBS-encoding gene expansion in perennial species. These duplication events, together with a higher probability of recombination revealed in this study, could compensate for the longer generation time in woody perennial species e.g. duplication and recombination could serve to generate novel resistance specificities. In addition, we observed extensive species-specific expansion in TIR-NBS-encoding genes. Non-TIR-NBS-encoding genes were poly- or paraphyletic, i.e. genes from three or more plant species were nested in different clades, suggesting different evolutionary patterns between these two gene types.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18563445?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zalesny, Jill A</style></author><author><style face="normal" font="default" size="100%">Zalesny, Ronald S</style></author><author><style face="normal" font="default" size="100%">Wiese, Adam H</style></author><author><style face="normal" font="default" size="100%">Sexton, Bart</style></author><author><style face="normal" font="default" size="100%">Hall, Richard B</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Sodium and chloride accumulation in leaf, woody, and root tissue of Populus after irrigation with landfill leachate.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">155</style></volume><pages><style face="normal" font="default" size="100%">72-80</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The response of Populus to irrigation sources containing elevated levels of sodium (Na(+)) and chloride (Cl(-)) is poorly understood. We irrigated eight Populus clones with fertilized well water (control) (N, P, K) or municipal solid waste landfill leachate weekly during 2005 and 2006 in Rhinelander, Wisconsin, USA (45.6 degrees N, 89.4 degrees W). During August 2006, we tested for differences in total Na(+) and Cl(-) concentration in preplanting and harvest soils, and in leaf, woody (stems+branches), and root tissue. The leachate-irrigated soils at harvest had the greatest Na(+) and Cl(-) levels. Genotypes exhibited elevated total tree Cl(-) concentration and increased biomass (clones NC14104, NM2, NM6), elevated Cl(-) and decreased biomass (NC14018, NC14106, DM115), or mid levels of Cl(-) and biomass (NC13460, DN5). Leachate tissue concentrations were 17 (Na(+)) and four (Cl(-)) times greater than water. Sodium and Cl(-) levels were greatest in roots and leaves, respectively.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18069106?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kuo, S</style></author><author><style face="normal" font="default" size="100%">Bembenek, R</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Sorption and desorption of chromate by wood shavings impregnated with iron or aluminum oxide.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioresource technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bioresour. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">99</style></volume><pages><style face="normal" font="default" size="100%">5617-25</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">This study examined the impregnation of hybrid poplar shavings with Fe or Al oxide and their reactivity with Cr(VI). The shavings were impregnated with an average of 1.24+/-0.18 mmol Fe g(-1) or 1.51+/-0.17 mmol Al g(-1), and the impregnated Fe or Al oxide was highly amorphous. Capacity of Cr(VI) sorption by impregnated shavings was high and rate of the sorption was rapid. While the freshly sorbed Cr on the Fe oxide-shavings was readily desorbed in 0.1M NaOH, nine weeks of ageing reduced the desorbability to only 6.5% of the sorbed Cr. Extraction with 0.1M NaOH remained feasible to recover most sorbed Cr from the Al oxide-shavings over the same ageing period. Impregnation of the shavings with Fe or Al oxide turns the wood waste into a product for removing Cr(VI) or other oxyanions from wastewater.</style></abstract><issue><style face="normal" font="default" size="100%">13</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18206368?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hu, Hai-Qing</style></author><author><style face="normal" font="default" size="100%">Guo, Fu-Tao</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Estimation of total carbon-containing gas emission from main tree species in forest fires in Daxing' an mountains].</style></title><secondary-title><style face="normal" font="default" size="100%">Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ying Yong Sheng Tai Xue Bao</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">19</style></volume><pages><style face="normal" font="default" size="100%">1884-90</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">By the method of emission factor (EF), this paper estimated the total carbon-containing gas emission from five main tree species in Daxing' an Mountains in forest fires from 1980 to 2005. The results showed that different tree species had different EF. Pinus sylvesstris var. mongolica and Populus davidiana had the maximum and minimum EF of CO2, respectively. Larix gmelinii and Betula platyphylla had the maximun EF of CO and C(x)H(y), while B. platyphylla and L. gmelinii had the minimum EF of CO and C(x)H(y). Based on the carbon storage in different organs and the total biomass of the tree, it was estimated that the total emission of CO2, CO and C(x)H(y) from the five tree in the 25 years was 16.58 Tg, 1.61 Tg and 0.54 Tg, and the contributions of L. gmelinii, P. sylvesstris var. mongolica, B. platyphylla, P. davidiana, and Quercus mongolica were 5.00 Tg, 0.63 Tg and 0.05 Tg, 0.225 Tg, 0.023 Tg and 0.003 Tg, 11.22 Tg, 0.83 Tg and 0.41 Tg, 0.0022 Tg, 0.004 Tg and 0.00034 Tg, and 3.12 Tg, 0.13 Tg and 0.062 Tg, respectively.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19102298?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Van Dillewijn, Pieter</style></author><author><style face="normal" font="default" size="100%">Couselo, José L</style></author><author><style face="normal" font="default" size="100%">Corredoira, Elena</style></author><author><style face="normal" font="default" size="100%">Delgado, Antonio</style></author><author><style face="normal" font="default" size="100%">Wittich, Rolf-Michael</style></author><author><style face="normal" font="default" size="100%">Ballester, Antonio</style></author><author><style face="normal" font="default" size="100%">Ramos, Juan L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Bioremediation of 2,4,6-trinitrotoluene by bacterial nitroreductase expressing transgenic aspen.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental science &amp; technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Sci. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Oct 1</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">42</style></volume><pages><style face="normal" font="default" size="100%">7405-10</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Trees belonging to the genus Populus are often used for phytoremediation due to their deep root formation, fast growth and high transpiration rates. Here, we study the capacity of transgenic hybrid aspen (Populus tremula x tremuloides var. Etropole) which expresses the bacterial nitroreductase gene, pnrA, to tolerate and take-up greater amounts of the toxic and recalcitrant explosive, 2,4,6-trinitrotoluene (TNT) from contaminated waters and soil. Transgenic aspen tolerate up to 57 mg TNT/L in hydroponic media and more than 1000 mg TNT/ kg soil, whereas the parental aspen could not endure in hydroponic culture with more than 11 mg TNT/L or soil with more than 500 mg TNT/kg. Likewise, the phytotoxicological limit for transgenic plants to a constant concentration of TNT was 20 mg TNT/L while wild-type plants only tolerated 10 mg TNT/L. Transgenic plants also showed improved uptake of TNT over wild-type plants when the original TNT concentration was above 35 mg TNT/L in liquid media or 750 mg TNT/kg in soil. Assays with 13C-labeled TNT show rapid adsorption of TNT to the root surface followed by a slower entrance rate into the plant. Most of the 13C-carbon from the labeled TNT taken up bythe plant (&gt; 95%) remains in the root with little translocation to the stem. Altogether, transgenic aspen expressing pnrA are highly interesting for phytoremediation applications on contaminated soil and underground aquifers.</style></abstract><issue><style face="normal" font="default" size="100%">19</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18939578?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kunert, Maritta</style></author><author><style face="normal" font="default" size="100%">Søe, Astrid</style></author><author><style face="normal" font="default" size="100%">Bartram, Stefan</style></author><author><style face="normal" font="default" size="100%">Discher, Sabrina</style></author><author><style face="normal" font="default" size="100%">Tolzin-Banasch, Karla</style></author><author><style face="normal" font="default" size="100%">Nie, Lihua</style></author><author><style face="normal" font="default" size="100%">David, Anja</style></author><author><style face="normal" font="default" size="100%">Pasteels, Jacques</style></author><author><style face="normal" font="default" size="100%">Boland, Wilhelm</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">De novo biosynthesis versus sequestration: a network of transport systems supports in iridoid producing leaf beetle larvae both modes of defense.</style></title><secondary-title><style face="normal" font="default" size="100%">Insect biochemistry and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Insect Biochem. Mol. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">38</style></volume><pages><style face="normal" font="default" size="100%">895-904</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In the larval chrysomelines the de novo synthesis of monoterpenoids (iridoids) is believed to represent the ancestral state in the evolution of chemical defenses. Here we demonstrate that the iridoid producing larvae of Plagiodera versicolora and Phratora laticollis have the potential to sequester precursors from food. In nature, iridoids may even have a dual origin, namely plant-derived and de novo produced. The ability to sequester plant-derived precursors was proved by (i) (13)C-labelling of the terpenoids in the food plant, (ii) by larval feeding on leaves impregnated with analogs and labelled putative precursors for iridoid biosynthesis; and (iii) by injection of the precursors into the hemolymph followed by mass spectroscopic analysis of their distribution in the hemolymph, defensive secretion, and faeces. The experimental findings support a network of transport systems which allows a broader range of glucosides to enter and to leave the hemocoel, while only the appropriate precursor, 8-hydroxygeraniol-8-O-beta-d-glucoside, is channelled to the reservoir and processed to iridoids. The dual system of de novo biosynthesis and sequestration of phytogenic precursors may have favoured the larvae to shift from one host plant to another without losing their defense.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18687400?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Barbehenn, Raymond V</style></author><author><style face="normal" font="default" size="100%">Jaros, Adam</style></author><author><style face="normal" font="default" size="100%">Yip, Lynn</style></author><author><style face="normal" font="default" size="100%">Tran, Lan</style></author><author><style face="normal" font="default" size="100%">Kanellis, Angelos K</style></author><author><style face="normal" font="default" size="100%">Constabel, C Peter</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Evaluating ascorbate oxidase as a plant defense against leaf-chewing insects using transgenic poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of chemical ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Chem. Ecol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">34</style></volume><pages><style face="normal" font="default" size="100%">1331-40</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Ascorbate is the major water-soluble antioxidant in plants and animals, and it is an essential nutrient for most insect herbivores. Therefore, ascorbate oxidase (AO) has been proposed to function as a plant defense that decreases the availability of ascorbate to insects. This hypothesis was tested by producing transgenic poplar (Populus tremula x Populus alba; Salicaceae) with 14- to 37-fold higher foliar AO activities than control (wild type) leaves and feeding these leaves to Lymantria dispar L. (Lepidoptera: Lymantriidae) caterpillars and Melanoplus sanguinipes (Fabricius) (Orthoptera: Acrididae) grasshoppers. To examine potential mechanisms of activity of AO in these insects, ascorbyl radical and/or ascorbate levels were measured in gut contents. No significant changes in ascorbyl radical or ascorbate levels were found in the midgut contents of L. dispar larvae that ingested the leaves of the AO-overexpressing genotypes compared to the control genotype, and no significant decreases in ascorbate levels were found in the foregut or midgut contents of M. sanguinipes. Treatment of control leaves with commercial AO also produced no changes in the midgut biochemistry of L. dispar larvae, as measured by levels of ascorbyl radicals. Likewise, no increase in oxidative stress was observed in L. dispar that consumed tannin-treated AO-overexpressing leaves compared with tannin-treated control genotype leaves. Performance experiments were carried out on first- and fourth-instar L. dispar larvae on leaf disks and on third instars feeding on intact leaves on trees. In no case was a significant difference found in the contrast between the control and three AO-overexpressing genotypes for relative consumption rate, relative growth rate, or nutritional indices. We conclude that elevated levels of AO in poplar are unlikely to serve as a defense against herbivores such as L. dispar or M. sanguinipes and that the low oxygen levels commonly found in the guts of caterpillars and grasshoppers may limit the activity of ingested AO in these leaf-chewing insects.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18773241?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Brentner, Laura B</style></author><author><style face="normal" font="default" size="100%">Mukherji, Sachiyo T</style></author><author><style face="normal" font="default" size="100%">Merchie, Kate M</style></author><author><style face="normal" font="default" size="100%">Yoon, Jong Moon</style></author><author><style face="normal" font="default" size="100%">Schnoor, Jerald L</style></author><author><style face="normal" font="default" size="100%">Van Aken, Benoit</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Expression of glutathione S-transferases in poplar trees (Populus trichocarpa) exposed to 2,4,6-trinitrotoluene (TNT).</style></title><secondary-title><style face="normal" font="default" size="100%">Chemosphere</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Chemosphere</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">73</style></volume><pages><style face="normal" font="default" size="100%">657-62</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Twelve Populus genes were identified from Arabidopsis thaliana sequences previously shown to be induced by exposure to 2,4,6-trinitrotoluene (TNT). Using the resources of the Poplar Genome Project and National Center for Biotechnology Information databases, Populus conserved domains were identified and used to design gene specific primers. RNA extracted from root tissues of TNT-exposed hydroponic poplar plants was used to quantify the expression of genes by reverse-transcriptase real-time polymerase chain reaction. Cyclophilin and 18S ribosomal DNA genes were used as internal standards. Exposure to TNT resulted in a significant increase of gene expression of two glutathione S-transferases (GST), peaking at levels of 25.0 +/- 13.1 and 10 +/- 0.7 fold the expression level of non-exposed plants after 24 h for each of the GST genes, respectively. This paper demonstrates the use of functional genomics information from the model plant species, Arabidopsis, to identify genes which may be important in detoxification of TNT in the model phytoremediation species, Populus trichocarpa.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18774158?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Yang, Zefeng</style></author><author><style face="normal" font="default" size="100%">Zhou, Yong</style></author><author><style face="normal" font="default" size="100%">Wang, Xuefeng</style></author><author><style face="normal" font="default" size="100%">Gu, Shiliang</style></author><author><style face="normal" font="default" size="100%">Yu, Jianmin</style></author><author><style face="normal" font="default" size="100%">Liang, Guohua</style></author><author><style face="normal" font="default" size="100%">Yan, Changjie</style></author><author><style face="normal" font="default" size="100%">Xu, Chenwu</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genomewide comparative phylogenetic and molecular evolutionary analysis of tubby-like protein family in Arabidopsis, rice, and poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Genomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">92</style></volume><pages><style face="normal" font="default" size="100%">246-53</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Tubby-like proteins, which are characterized by a highly conserved tubby domain, play an important role in the maintenance and function of neuronal cells during postdifferentiation and development in mammals. In additional to the tubby domain, most tubby-like proteins in plants also possess an F-box domain. Plants also appear to harbor a large number of TLP genes. To gain insight into how TLP genes evolved in plants, we conducted a comparative phylogenetic and molecular evolutionary analysis of the tubby-like protein gene family in Arabidopsis, rice, and poplar. Genomewide screening identified 11 TLP genes in Arabidopsis, 14 in rice, and 11 in poplar. Phylogenetic trees, domain organizations, and intron/exon structures classified this family into three subfamilies and indicated that species-specific expansion contributed to the evolution of this family in plants. We determined that in rice and poplar, the tubby-like protein family had expanded mainly through segmental duplication events. Tissue-specific expression analysis indicated that functional diversification of the duplicated TLP genes was a major feature of long-term evolution. Our results also demonstrated that the tubby and F-box domains had co-evolved during the evolution of proteins containing both domains.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18620041?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Duan, Baoli</style></author><author><style face="normal" font="default" size="100%">Xuan, Zuying</style></author><author><style face="normal" font="default" size="100%">Zhang, Xiaolu</style></author><author><style face="normal" font="default" size="100%">Korpelainen, Helena</style></author><author><style face="normal" font="default" size="100%">Li, Chunyang</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Interactions between drought, ABA application and supplemental UV-B in Populus yunnanensis.</style></title><secondary-title><style face="normal" font="default" size="100%">Physiologia plantarum</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Physiol Plant</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">134</style></volume><pages><style face="normal" font="default" size="100%">257-69</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">To test whether drought and ABA application alter the effects of enhanced UV-B on the growth and biomass allocation of Populus yunnanensis Dode, cuttings were grown in pots at two ABA levels, two watering regimes and two UV-B levels for one growth season. Exposure to enhanced UV-B radiation significantly decreased plant growth and photosynthesis under well-watered conditions, but these effects were obscured by drought, which alone caused growth reduction. Drought may contribute to masking the effects of UV-B radiation. The accumulation of UV-B absorbing compounds and the increase of the ABA content induced by drought could reduce the effectiveness of UV-B radiation. ABA application did not have large direct effects on biomass accumulation and allocation. Evidence for interactions between UV-B and ABA was detected for only a few measured traits. Therefore, there was little evidence to support a pivotal role for ABA in regulating a centralized whole plant response to enhanced UV-B. Yet, we recorded an ABA-induced decrease in stomatal conductance (g(s)) and increase in UV-B absorbing compounds and carbon isotope composition (delta(13)C) in response to enhanced UV-B. The allometric analysis revealed that regression models between root and shoot biomass in response to enhanced UV-B are different for plants under well-watered and drought conditions. Enhanced UV-B led to a significant displacement of the allometric regression line under well-watered condition, while allometric trajectories for both UV-B regimes did not differ significantly under drought condition.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18485056?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Cheng, Qiang</style></author><author><style face="normal" font="default" size="100%">Cao, Youzhi</style></author><author><style face="normal" font="default" size="100%">Pan, Huixin</style></author><author><style face="normal" font="default" size="100%">Wang, Mingxiu</style></author><author><style face="normal" font="default" size="100%">Huang, Minren</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Isolation and characterization of two genes encoding polygalacturonase-inhibiting protein from Populus deltoides.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of genetics and genomics = Yi chuan xue bao</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J Genet Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">35</style></volume><pages><style face="normal" font="default" size="100%">631-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Polygalacturonase-inhibiting proteins (PGIPs) are extracellular proteins that belong to the leucine-rich repeat (LRR) protein superfamily. PGIPs inhibit fungal polygalacturonases (PGs) and promote accumulation of oligogalacturonides, which activate plant defense responses. PGIPs play important roles in resistance to infection of pathogens. In this study, reverse transcriptase-polymerase chain reaction (RT-PCR) and RNA ligase-mediated rapid amplification of cDNA ends (RLM-RACE) were used to isolate the full-length PGIP cDNA from Populus deltoides (GenBank accession no. of PdPGIP2 and PdPGIP4: EF684913 and EF684912). Domain analysis revealed that the deduced amino acid sequences of PdPGIP2 and PdPGIP4 had a typical PGIP topology. Phylogenetic analysis of known PGIPs indicated that the two PdPGIPs were clustered to the defense-related PGIP clade. Using real-time RT-PCR, the expression patterns of the two PdPGIPs following treatment with a fungal pathogen and defense-related signaling molecules were studied. The expression levels of PdPGIP2 and PdPGIP4 were both up-regulated when inoculated with the phytopathogenic fungus Marssonina brunnea. Therefore, it was proposed that the two PGIPs might be involved in the resistance to Marssonina brunnea in P. deltoides.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18937920?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Margis-Pinheiro, Marcia</style></author><author><style face="normal" font="default" size="100%">Zolet, Andreia Carina Turchetto</style></author><author><style face="normal" font="default" size="100%">Loss, Guilherme</style></author><author><style face="normal" font="default" size="100%">Pasquali, Giancarlo</style></author><author><style face="normal" font="default" size="100%">Margis, Rogerio</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Molecular evolution and diversification of plant cysteine proteinase inhibitors: new insights after the poplar genome.</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular phylogenetics and evolution</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Phylogenet. Evol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">49</style></volume><pages><style face="normal" font="default" size="100%">349-55</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18547822?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hou, W</style></author><author><style face="normal" font="default" size="100%">Li, H</style></author><author><style face="normal" font="default" size="100%">Zhang, B</style></author><author><style face="normal" font="default" size="100%">Huang, M</style></author><author><style face="normal" font="default" size="100%">Wu, R</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A nonlinear mixed-effect mixture model for functional mapping of dynamic traits.</style></title><secondary-title><style face="normal" font="default" size="100%">Heredity</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Heredity (Edinb)</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">101</style></volume><pages><style face="normal" font="default" size="100%">321-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Functional mapping has emerged as a next-generation statistical tool for mapping quantitative trait loci (QTL) that affect complex dynamic traits. In this article, we incorporated the idea of nonlinear mixed-effect (NLME) models into the mixture-based framework of functional mapping, aimed to generalize the spectrum of applications for functional mapping. NLME-based functional mapping, implemented with the linearization algorithm based on the first-order Taylor expansion, can provide reasonable estimates of QTL genotypic-specific curve parameters (fixed effect) and the between-individual variation of these parameters (random effect). Results from simulation studies suggest that the NLME-based model is more general than traditional functional mapping. The new model can be useful for the identification of the ontogenetic patterns of QTL genetic effects during time course.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18612322?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Siemens, J Aurea</style></author><author><style face="normal" font="default" size="100%">Zwiazek, Janusz J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Root hydraulic properties and growth of balsam poplar (Populus balsamifera) mycorrhizal with Hebeloma crustuliniforme and Wilcoxina mikolae var. mikolae.</style></title><secondary-title><style face="normal" font="default" size="100%">Mycorrhiza</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mycorrhiza</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">18</style></volume><pages><style face="normal" font="default" size="100%">393-401</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The effects of an E-strain fungus (Wilcoxina mikolae var. mikolae) and an ectomycorrhizal fungus (Hebeloma crustuliniforme) on growth and water relations of balsam poplar were examined and compared in the present study. Balsam poplar roots inoculated with W. mikolae var. mikolae (Wm) exhibited structures consistent with ectendomycorrhizal (EEM) associations, including a mantle surrounding the outside of the root and an extensive Hartig net that was located between cortical cells and extended to the vascular cylinder. Roots colonized with H. crustuliniforme (Hc) developed a mantle layer, indicative of an ectomycorrhizal (ECM) association, around the outer part of the root, but no distinct Hartig net was present. Wm-colonized balsam poplar also showed increased shoot growth, stomatal conductance (g(s)), and root volumes compared with non-inoculated and Hc-inoculated plants. However, Hc-inoculated plants had higher root hydraulic conductivity (L(pr)) compared with non-inoculated plants and Wm-inoculated plants. These results suggest that L(pr) was not a growth-limiting factor in balsam poplar and that hyphal penetration of the root cortex in itself may have little influence on root hydraulic properties.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18685871?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Fluch, Silvia</style></author><author><style face="normal" font="default" size="100%">Olmo, Christian Carlo</style></author><author><style face="normal" font="default" size="100%">Tauber, Stefanie</style></author><author><style face="normal" font="default" size="100%">Stierschneider, Michael</style></author><author><style face="normal" font="default" size="100%">Kopecky, Dieter</style></author><author><style face="normal" font="default" size="100%">Reichenauer, Thomas G</style></author><author><style face="normal" font="default" size="100%">Matusíková, Ildikó</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Transcriptomic changes in wind-exposed poplar leaves are dependent on developmental stage.</style></title><secondary-title><style face="normal" font="default" size="100%">Planta</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Planta</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">228</style></volume><pages><style face="normal" font="default" size="100%">757-64</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Responses of plant tissue to environmental challenges can vary among different plant parts and among plants of different ages. Investment into defense has been proposed to be influenced by fitness value and/or allocation of available resources. Here we show at first time at transcriptome level that plant defense is non-linear. On very young, expanding, adult and old leaves of Populus nigra plants exposed to air perturbation, we studied the ontogenic trajectory of gene expression changes to such a low-dose factor similar to wind. Although plant responses to mechanical sensation (wind, touch) are described and summarized as thigmomorphogenesis, the knowledge on the molecular background of plant responses to wind is largely incomplete. Our data describe which genes are activated during a ubiquitous and continuous environmental factor such as wind, and based on existing knowledge complement the picture on ongoing processes.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18719940?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Fang, Sheng-Zuo</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Silviculture of poplar plantation in China: a review].</style></title><secondary-title><style face="normal" font="default" size="100%">Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ying Yong Sheng Tai Xue Bao</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">19</style></volume><pages><style face="normal" font="default" size="100%">2308-16</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">There are more than 7.0 million hm2 of poplar plantation in China, ranking top one in the world. To meet the needs of a growing world for social-economic development, environmental improvement, and sustainable development through poplar plantation establishment is a main research interest in the globe. This paper introduced the regionalizing cultivation, key planting clones, and productivities of poplar plantations in China, and summarized the recent 10 years research progress in China in the site quality evaluation, seedling propagation techniques, management patterns, mixed plantation establishment, agroforestry management system, water and nutrient management techniques, site productivity maintenance, and ecological functions of poplar plantation. The potential productivity, general allocation, oriented silviculture, and environmental function study of poplar plantation were also discussed and prospected. The contents of this paper would provide some references for the silviculture and sustainable management of poplar plantation in China.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19123371?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Stanhope, Andrine</style></author><author><style face="normal" font="default" size="100%">Berry, Christopher J</style></author><author><style face="normal" font="default" size="100%">Brigmon, Robin L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Phytoremediation of chlorinated ethenes in seepline sediments: tree selection.</style></title><secondary-title><style face="normal" font="default" size="100%">International journal of phytoremediation</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Int J Phytoremediation</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Nov-Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">10</style></volume><pages><style face="normal" font="default" size="100%">529-46</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Phytoremediation of chlorinated ethene (CE)-contaminated water was investigated at the Savannah River Site in Aiken, SC, USA. Perchloroethylene (PCE) and trichloroethylene (TCE) are present where CE-contaminated groundwater currently outcrops in seepline soils. Results of constructed and planted test cells, filled with soil from a noncontaminated seepline area and supplied with CE-contaminated groundwater (48 ppb) in the field for one season are presented. These test cells were planted with loblolly pines, hybrid poplars, coyote willow, and sweet gum. Cis-dichloroethylene (cDCE), a byproduct from rhizosphere microbial activity, was detected in the soils as well as some tree tissues. All trees tested were found to uptake both PCE and TCE (5-50 pbb/gm dry wt).</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19260231?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Purves, Drew W</style></author><author><style face="normal" font="default" size="100%">Lichstein, Jeremy W</style></author><author><style face="normal" font="default" size="100%">Strigul, Nikolay</style></author><author><style face="normal" font="default" size="100%">Pacala, Stephen W</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Predicting and understanding forest dynamics using a simple tractable model.</style></title><secondary-title><style face="normal" font="default" size="100%">Proceedings of the National Academy of Sciences of the United States of America</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Proc. Natl. Acad. Sci. U.S.A.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Nov 4</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">105</style></volume><pages><style face="normal" font="default" size="100%">17018-22</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The perfect-plasticity approximation (PPA) is an analytically tractable model of forest dynamics, defined in terms of parameters for individual trees, including allometry, growth, and mortality. We estimated these parameters for the eight most common species on each of four soil types in the US Lake states (Michigan, Wisconsin, and Minnesota) by using short-term (&lt;/=15-year) inventory data from individual trees. We implemented 100-year PPA simulations given these parameters and compared these predictions to chronosequences of stand development. Predictions for the timing and magnitude of basal area dynamics and ecological succession on each soil were accurate, and predictions for the diameter distribution of 100-year-old stands were correct in form and slope. For a given species, the PPA provides analytical metrics for early-successional performance (H(20), height of a 20-year-old open-grown tree) and late-successional performance (Z*, equilibrium canopy height in monoculture). These metrics predicted which species were early or late successional on each soil type. Decomposing Z* showed that (i) succession is driven both by superior understory performance and superior canopy performance of late-successional species, and (ii) performance differences primarily reflect differences in mortality rather than growth. The predicted late-successional dominants matched chronosequences on xeromesic (Quercus rubra) and mesic (codominance by Acer rubrum and Acer saccharum) soil. On hydromesic and hydric soils, the literature reports that the current dominant species in old stands (Thuja occidentalis) is now failing to regenerate. Consistent with this, the PPA predicted that, on these soils, stands are now succeeding to dominance by other late-successional species (e.g., Fraxinus nigra, A. rubrum).</style></abstract><issue><style face="normal" font="default" size="100%">44</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18971335?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kim, Bong-Gyu</style></author><author><style face="normal" font="default" size="100%">Lee, Yoon Jung</style></author><author><style face="normal" font="default" size="100%">Lee, Sunhee</style></author><author><style face="normal" font="default" size="100%">Lim, Yoongho</style></author><author><style face="normal" font="default" size="100%">Cheong, Youhoon</style></author><author><style face="normal" font="default" size="100%">Ahn, Joong-Hoon</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Altered regioselectivity of a poplar O-methyltransferase, POMT-7.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of biotechnology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Biotechnol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Nov 25</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">138</style></volume><pages><style face="normal" font="default" size="100%">107-11</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">O-Methylated flavonoids are biosynthesized by regioselective flavonoid O-methyltransferases (OMTs), which may account for the limited number of naturally occurring flavonoids in nature. It was previously shown that poplar POMT-7 regioselectively methylates the 7-hydroxyl group of flavones, whereas rice ROMT-9 regioselectively methylates the 3'-hydroxyl group of the substrate. We co-expressed both OMT genes (POMT-7 and ROMT-9) in E. coli and carried out biotransformation experiments of some flavonoids with the transformed E. coli strain. Contrast to the predicted regioselectivity of both POMT-7 and ROMT-9, unexpected methylation reaction products, i.e. 3',4'-O-methylated flavonoids, in addition to the predicted ones, were obtained with luteolin (5,7,3',4'-tetrahydroxyflavone) and quercetin (3,5,7,3',4'-pentahydroxyflavone) as substrates. Reactions using the 3'-O-methyl derivative of luteolin and quercetin by POMT-7 revealed that the enzyme has altered its regioselectivity from the 7- to the 4'-hydroxyl groups. These results are discussed in terms of molecular modeling of POMT-7 in relation to its methyl donor.</style></abstract><issue><style face="normal" font="default" size="100%">3-4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18817819?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ally, D</style></author><author><style face="normal" font="default" size="100%">Ritland, K</style></author><author><style face="normal" font="default" size="100%">Otto, S P</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Can clone size serve as a proxy for clone age? An exploration using microsatellite divergence in Populus tremuloides.</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Ecol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">17</style></volume><pages><style face="normal" font="default" size="100%">4897-911</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In long-lived clonal plants, the overall size of a clone is often used to estimate clone age. The size of a clone, however, might be largely determined by physical or biotic interactions, obscuring the relationship between clone size and age. Here, we use the accumulation of mutations at 14 microsatellite loci to estimate clone age in trembling aspen (Populus tremuloides) from southwestern Canada. We show that the observed patterns of genetic divergence are consistent with a model of increasing ramet population size, allowing us to use pairwise genetic divergence as an estimator of clone age. In the populations studied, clone size did not exhibit a significant relationship with microsatellite divergence, indicating that clone size is not a good proxy for clone age. In P. tremuloides, the per-locus per-year neutral somatic mutation rate across 14 microsatellite loci was estimated to lie between 6 x 10(-7) (lower bound) and 4 x 10(-5) (upper bound).</style></abstract><issue><style face="normal" font="default" size="100%">22</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19140980?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Mock, K E</style></author><author><style face="normal" font="default" size="100%">Rowe, C A</style></author><author><style face="normal" font="default" size="100%">Hooten, M B</style></author><author><style face="normal" font="default" size="100%">Dewoody, J</style></author><author><style face="normal" font="default" size="100%">Hipkins, V D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Clonal dynamics in western North American aspen (Populus tremuloides).</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Ecol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">17</style></volume><pages><style face="normal" font="default" size="100%">4827-44</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Clonality is a common phenomenon in plants, allowing genets to persist asexually for much longer periods of time than ramets. The relative frequency of sexual vs. asexual reproduction determines long-term dominance and persistence of clonal plants at the landscape scale. One of the most familiar and valued clonal plants in North America is aspen (Populus tremuloides). Previous researchers have suggested that aspen in xeric landscapes of the intermountain west represent genets of great chronological age, maintained via clonal expansion in the near absence of sexual reproduction. We synthesized microsatellite data from 1371 ramets in two large sampling grids in Utah. We found a surprisingly large number of distinct genets, some covering large spatial areas, but most represented by only one to a few individual ramets at a sampling scale of 50 m. In general, multi-ramet genets were spatially cohesive, although some genets appear to be fragmented remnants of much larger clones. We conclude that recent sexual reproduction in these landscapes is a stronger contributor to standing genetic variation at the population level than the accumulation of somatic mutations, and that even some of the spatially large clones may not be as ancient as previously supposed. Further, a striking majority of the largest genets in both study areas had three alleles at one or more loci, suggesting triploidy or aneuploidy. These genets tended to be spatially clustered but not closely related. Together, these findings substantially advance our understanding of clonal dynamics in western North American aspen, and set the stage for a broad range of future studies.</style></abstract><issue><style face="normal" font="default" size="100%">22</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19140975?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Xu, Xiao</style></author><author><style face="normal" font="default" size="100%">Peng, Guoquan</style></author><author><style face="normal" font="default" size="100%">Wu, Chengchun</style></author><author><style face="normal" font="default" size="100%">Korpelainen, Helena</style></author><author><style face="normal" font="default" size="100%">Li, Chunyang</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Drought inhibits photosynthetic capacity more in females than in males of Populus cathayana.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">1751-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We investigated sex-related photosynthetic responses to drought in the dioecious species, Populus cathayana Rehd. Plants were subjected to two watering regimes (100% and 30% of field capacity) in a semi-controlled environment. Drought significantly decreased leaf area (LA), total number of leaves (TNL), specific leaf area (SLA), relative water content, net photosynthetic rate (P(n)), transpiration (E), stomatal conductance (g(s)), intercellular CO(2) concentration (C(i)), light saturation point (L(SP)), apparent quantum yield (Phi), carboxylation efficiency (CE), light-saturated photosynthetic rate (P(max)), maximum efficiency of PSII (F(v)/F(m)) and maximum effective quantum yield of PSII (Yield), and increased the total chlorophyll concentration (TC), CO(2) compensation point (Gamma), non-photochemical quenching coefficient, peroxidase (POD) activity and carbon isotope composition (delta(13)C). Moreover, differences between males and females were detected in many of these responses. In the drought treatment, males exhibited significantly higher LA, TNL, TC, concentration of carotenoids (Caro), P(n), E, g(s), C(i), L(SP), Phi, CE, P(max), F(v)/F(m), photochemical quenching coefficient, POD activity and delta(13)C, but a lower SLA, chlorophyll a/b ratio, carotenoids/total chlorophyll ratio and Gamma than females. However, Caro, L(SP), Gamma, Phi, CE and POD activity were apparently associated with sex-related resource demands, because significant differences in these traits were detected between the sexes under well-watered conditions. Our results indicate that drought stress limits photosynthetic capacity more in females than in males.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18765380?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Yang, Xiaohan</style></author><author><style face="normal" font="default" size="100%">Kalluri, Udaya C</style></author><author><style face="normal" font="default" size="100%">Jawdy, Sara</style></author><author><style face="normal" font="default" size="100%">Gunter, Lee E</style></author><author><style face="normal" font="default" size="100%">Yin, Tongming</style></author><author><style face="normal" font="default" size="100%">Tschaplinski, Timothy J</style></author><author><style face="normal" font="default" size="100%">Weston, David J</style></author><author><style face="normal" font="default" size="100%">Ranjan, Priya</style></author><author><style face="normal" font="default" size="100%">Tuskan, Gerald A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The F-box gene family is expanded in herbaceous annual plants relative to woody perennial plants.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">148</style></volume><pages><style face="normal" font="default" size="100%">1189-200</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">F-box proteins are generally responsible for substrate recognition in the Skp1-Cullin-F-box complexes that are involved in protein degradation via the ubiquitin-26S proteasome pathway. In plants, F-box genes influence a variety of biological processes, such as leaf senescence, branching, self-incompatibility, and responses to biotic and abiotic stresses. The number of F-box genes in Populus (Populus trichocarpa; approximately 320) is less than half that found in Arabidopsis (Arabidopsis thaliana; approximately 660) or Oryza (Oryza sativa; approximately 680), even though the total number of genes in Populus is equivalent to that in Oryza and 1.5 times that in Arabidopsis. We performed comparative genomics analysis between the woody perennial plant Populus and the herbaceous annual plants Arabidopsis and Oryza in order to explicate the functional implications of this large gene family. Our analyses reveal interspecific differences in genomic distribution, orthologous relationship, intron evolution, protein domain structure, and gene expression. The set of F-box genes shared by these species appear to be involved in core biological processes essential for plant growth and development; lineage-specific differences primarily occurred because of an expansion of the F-box genes via tandem duplications in Arabidopsis and Oryza. The number of F-box genes in the newly sequenced woody species Vitis (Vitis vinifera; 156) and Carica (Carica papaya; 139) is similar to that in Populus, supporting the hypothesis that the F-box gene family is expanded in herbaceous annual plants relative to woody perennial plants. This study provides insights into the relationship between the structure and composition of the F-box gene family in herbaceous and woody species and their associated developmental and physiological features.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18775973?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Canam, Thomas</style></author><author><style face="normal" font="default" size="100%">Unda, Faride</style></author><author><style face="normal" font="default" size="100%">Mansfield, Shawn D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Heterologous expression and functional characterization of two hybrid poplar cell-wall invertases.</style></title><secondary-title><style face="normal" font="default" size="100%">Planta</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Planta</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">228</style></volume><pages><style face="normal" font="default" size="100%">1011-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The expression of two hybrid poplar cell-wall invertases (EC 3.2.1.26; PaxgINV1 and PaxgINV2) were previously shown to be spatially and temporally regulated in the vegetative tissues. The expression of PaxgINV1 was linked to processes relating to dormancy, while PaxgINV2 expression was prominent in tissues undergoing growth and expansion. In an effort to further elucidate the physiological roles of these key cell wall enzymes, PaxgINV1 and PaxgINV2 were heterologously expressed in the methylotrophic yeast Pichia pastoris. Three-dimensional predictive models of the poplar invertases revealed a structural channel containing both the conserved beta-fructofuranosidase and cell-wall invertase motifs, suggesting that this channel is the putative active site of these enzymes. Recombinant PaxgINV1 and PaxgINV2 had pH optima of 4.8 and 5.6 and temperature optima of 45 and 40 degrees C, respectively. Functional characterization revealed the ability for both enzymes to hydrolyze the fructose residue of sucrose, raffinose, stachyose and verbascose, with PaxgINV2 having higher specific activity for each of the substrates tested. The K(m) values of sucrose/raffinose/stachyose were 1.7/1.8/5.0 mM for PaxgINV1 and 1.6/1.7/1.9 mM for PaxgINV2, respectively. Activity analyses in the presence of various metal cations showed that PaxgINV2 was strongly inhibited by Cu(2+), Zn(2+) and Hg(2+), while PaxgINV1 was only weakly inhibited by these cations. The results from this study, coupled with previous expression data, suggest that PaxgINV1 and PaxgINV2 have distinct roles with respect to the physiology and development of hybrid poplar, specifically phloem unloading and processes related to dormancy and bud break.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18704491?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Solti, Adám</style></author><author><style face="normal" font="default" size="100%">Gáspár, László</style></author><author><style face="normal" font="default" size="100%">Mészáros, Ilona</style></author><author><style face="normal" font="default" size="100%">Szigeti, Zoltán</style></author><author><style face="normal" font="default" size="100%">Lévai, László</style></author><author><style face="normal" font="default" size="100%">Sárvári, Eva</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Impact of iron supply on the kinetics of recovery of photosynthesis in Cd-stressed poplar (Populus glauca).</style></title><secondary-title><style face="normal" font="default" size="100%">Annals of botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ann. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">102</style></volume><pages><style face="normal" font="default" size="100%">771-82</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Cadmium (Cd) causes Fe-deficiency-like symptoms in plants, and strongly inhibits photosynthesis. To clarify the importance of Cd-induced Fe deficiency in Cd effects on photosynthesis, the recovery processes were studied by supplying excess Fe after the Cd symptoms had developed.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18757882?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Coleman, Heather D</style></author><author><style face="normal" font="default" size="100%">Samuels, A Lacey</style></author><author><style face="normal" font="default" size="100%">Guy, Robert D</style></author><author><style face="normal" font="default" size="100%">Mansfield, Shawn D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Perturbed lignification impacts tree growth in hybrid poplar--a function of sink strength, vascular integrity, and photosynthetic assimilation.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">148</style></volume><pages><style face="normal" font="default" size="100%">1229-37</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The effects of reductions in cell wall lignin content, manifested by RNA interference suppression of coumaroyl 3'-hydroxylase, on plant growth, water transport, gas exchange, and photosynthesis were evaluated in hybrid poplar trees (Populus alba x grandidentata). The growth characteristics of the reduced lignin trees were significantly impaired, resulting in smaller stems and reduced root biomass when compared to wild-type trees, as well as altered leaf morphology and architecture. The severe inhibition of cell wall lignification produced trees with a collapsed xylem phenotype, resulting in compromised vascular integrity, and displayed reduced hydraulic conductivity and a greater susceptibility to wall failure and cavitation. In the reduced lignin trees, photosynthetic carbon assimilation and stomatal conductance were also greatly reduced, however, shoot xylem pressure potential and carbon isotope discrimination were higher and water-use efficiency was lower, inconsistent with water stress. Reductions in assimilation rate could not be ascribed to increased stomatal limitation. Starch and soluble sugars analysis of leaves revealed that photosynthate was accumulating to high levels, suggesting that the trees with substantially reduced cell wall lignin were not carbon limited and that reductions in sink strength were, instead, limiting photosynthesis.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18805953?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Heinze, Berthold</style></author><author><style face="normal" font="default" size="100%">Fussi, Barbara</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Somatic mutations as a useful tool for studying clonal dynamics in trees.</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Ecol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">17</style></volume><pages><style face="normal" font="default" size="100%">4779-81</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The seemingly eternal cycles of clonal growth in many tree species, with members of Populus (aspen, poplars, cottonwoods and the like) featuring most prominently, provoke a number of questions on the interface between ecology, genetics and forestry. In this issue, two groups present their approaches to clonal dynamics (Ally et al. 2008 and Mock et al. 2008), using microsatellite (or simple sequence repeat, SSR) variation in P. tremuloides. Ally et al. developed and applied a model for using microsatellites to estimate clone age and infer other community characteristics. Mock et al. used fewer microsatellites but in more individuals, to examine clone size and distribution across the landscape.</style></abstract><issue><style face="normal" font="default" size="100%">22</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19140970?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Goswami, Luna</style></author><author><style face="normal" font="default" size="100%">Dunlop, John W C</style></author><author><style face="normal" font="default" size="100%">Jungnikl, Karin</style></author><author><style face="normal" font="default" size="100%">Eder, Michaela</style></author><author><style face="normal" font="default" size="100%">Gierlinger, Notburga</style></author><author><style face="normal" font="default" size="100%">Coutand, Catherine</style></author><author><style face="normal" font="default" size="100%">Jeronimidis, George</style></author><author><style face="normal" font="default" size="100%">Fratzl, Peter</style></author><author><style face="normal" font="default" size="100%">Burgert, Ingo</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Stress generation in the tension wood of poplar is based on the lateral swelling power of the G-layer.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">56</style></volume><pages><style face="normal" font="default" size="100%">531-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The mechanism of active stress generation in tension wood is still not fully understood. To characterize the functional interdependency between the G-layer and the secondary cell wall, nanostructural characterization and mechanical tests were performed on native tension wood tissues of poplar (Populus nigra x Populus deltoids) and on tissues in which the G-layer was removed by an enzymatic treatment. In addition to the well-known axial orientation of the cellulose fibrils in the G-layer, it was shown that the microfibril angle of the S2-layer was very large (about 36 degrees). The removal of the G-layer resulted in an axial extension and a tangential contraction of the tissues. The tensile stress-strain curves of native tension wood slices showed a jagged appearance after yield that could not be seen in the enzyme-treated samples. The behaviour of the native tissue was modelled by assuming that cells deform elastically up to a critical strain at which the G-layer slips, causing a drop in stress. The results suggest that tensile stresses in poplar are generated in the living plant by a lateral swelling of the G-layer which forces the surrounding secondary cell wall to contract in the axial direction.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18643995?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Arend, M</style></author><author><style face="normal" font="default" size="100%">Muninger, M</style></author><author><style face="normal" font="default" size="100%">Fromm, J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Unique occurrence of pectin-like fibrillar cell wall deposits in xylem fibres of poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant biology (Stuttgart, Germany)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Biol (Stuttg)</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">10</style></volume><pages><style face="normal" font="default" size="100%">763-70</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Using light and electron microscopic techniques, we studied the unique occurrence of fibrillar cell wall deposits in mature xylem fibres from poplar. These cell wall deposits lined the lumen-facing side of the wall, mainly in fibres next to vessel elements. Different lines of evidence point to the pectin-like nature of these fibrillar cell wall deposits. First, specific staining by Alcian Blue 8GX, a dye with high affinity for pectic substances. Second, the strongly reduced staining of the cell wall deposits in microscopic sections treated with pectolytic enzyme. Third, concomitant staining of pits, which are known to consist mainly of pectic substances. Given the pectin-like nature of the fibrillar cell wall deposits as well as their preferred occurrence in fibres neighbouring water-conducting vessel elements, a function for the fibrillar cell wall deposits in lateral water diffusion and stem water storage is hypothesised. The hypothesis is supported by the increased abundance of these cell wall deposits in wood tissue of a drought-sensitive poplar species.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18950434?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Liu, Jiyan</style></author><author><style face="normal" font="default" size="100%">Schnoor, Jerald L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Uptake and translocation of lesser-chlorinated polychlorinated biphenyls (PCBs) in whole hybrid poplar plants after hydroponic exposure.</style></title><secondary-title><style face="normal" font="default" size="100%">Chemosphere</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Chemosphere</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">73</style></volume><pages><style face="normal" font="default" size="100%">1608-16</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Mono-, di-, tri-, and tetra-chlorinated polychlorinated biphenyls (PCBs) are congeners with greater volatility which remain in air, soils and sediments requiring treatment. In this study, the fate of these PCBs was investigated within whole poplar plants (Populus deltoides x nigra, DN34) with application for a treatment system such as a confined disposal facility for dredged material. Whole hybrid poplars were exposed hydroponically to a mixture of five congeners, common in the environment, having one to four chlorine atoms per molecule. Results indicated that PCB 3, 15, 28, 52, and 77 were initially sorbed to the root systems. The root concentration factor (RCF) of PCBs during the exposure was calculated and correlated with K(ow). PCB congeners were taken up by the roots of hybrid poplar, and the translocation of PCBs to stems was inversely related to congener hydrophobicity (log K(ow)). PCB 3 and 15 were translocated to the upper stem at small but significant rates. PCB 28 was translocated to the wood of the main stem but no farther; translocation from the roots was not detected for PCB 52 and 77. The distribution of PCBs within poplars was determined, and mass balances were completed to within 15% for each chemical except for PCB 3, the most volatile congener. This is the first report on the transport of PCBs through whole plants designed for use in treatment at disposal facilities.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18793792?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rudsander, Ulla J</style></author><author><style face="normal" font="default" size="100%">Sandstrom, Corine</style></author><author><style face="normal" font="default" size="100%">Piens, Kathleen</style></author><author><style face="normal" font="default" size="100%">Master, Emma R</style></author><author><style face="normal" font="default" size="100%">Wilson, David B</style></author><author><style face="normal" font="default" size="100%">Brumer Iii, Harry</style></author><author><style face="normal" font="default" size="100%">Kenne, Lennart</style></author><author><style face="normal" font="default" size="100%">Teeri, Tuula T</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Comparative NMR analysis of cellooligosaccharide hydrolysis by GH9 bacterial and plant endo-1,4-beta-glucanases.</style></title><secondary-title><style face="normal" font="default" size="100%">Biochemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biochemistry</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 May 6</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">47</style></volume><pages><style face="normal" font="default" size="100%">5235-41</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">1H NMR spectroscopy has been used to analyze the product profiles arising from the hydrolysis of cellooligosaccharides by family GH9 cellulases. The product profiles obtained with the wild type and several active site mutants of a bacterial processive endoglucanase, TfCel9A, were compared with those obtained by a randomly acting plant endoglucanase, PttCel9A. PttCel9A is an orthologue of the Arabidopsis endocellulase, Korrigan, which is required for efficient cellulose biosynthesis. As expected, poplar PttCel9A was shown to catalyze the degradation of cellooligosaccharides by inversion of the configuration of the anomeric carbon. The product analyses showed that the number of interactions between the glucose units of the substrate and the aromatic residues in the enzyme active sites determines the point of cleavage in both enzymes.</style></abstract><issue><style face="normal" font="default" size="100%">18</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18402467?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhu, Bo</style></author><author><style face="normal" font="default" size="100%">Xiong, Ai-Sheng</style></author><author><style face="normal" font="default" size="100%">Peng, Ri-He</style></author><author><style face="normal" font="default" size="100%">Xu, Jing</style></author><author><style face="normal" font="default" size="100%">Zhou, Jun</style></author><author><style face="normal" font="default" size="100%">Xu, Jin-Tao</style></author><author><style face="normal" font="default" size="100%">Jin, Xiao-Fen</style></author><author><style face="normal" font="default" size="100%">Zhang, Yang</style></author><author><style face="normal" font="default" size="100%">Hou, Xi-Lin</style></author><author><style face="normal" font="default" size="100%">Yao, Quan-Hong</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Heat stress protection in Aspen sp1 transgenic Arabidopsis thaliana.</style></title><secondary-title><style face="normal" font="default" size="100%">BMB reports</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMB Rep</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 May 31</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">41</style></volume><pages><style face="normal" font="default" size="100%">382-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">It is known that the stable protein 1 (SP1) detected in aspen plants remains soluble upon boiling and that sp1 expression in transgenic aspen is resistant to salt stress. Presently, we analyzed the effect of expression of SP1 in Arabidopsis thaliana plants and their response to high temperature stress. After 45 degrees C for 16 h, relative to wild type plants, sp1 transgenic plants exhibited stronger growth and were better in several physiological properties including chlorophyll, chlorophyll fluorescence, water content, proline content, and malondialdehyde content. These preliminarily results suggest that the over-expression of SP1 may notably enhance heat-tolerant level of transgenic A. thaliana plants.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18510869?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Westermann, Janneke</style></author><author><style face="normal" font="default" size="100%">Zerbe, Stefan</style></author><author><style face="normal" font="default" size="100%">Eckstein, Dieter</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Age structure and growth of degraded Populus euphratica floodplain forests in north-west China and perspectives for their recovery.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of integrative plant biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J Integr Plant Biol</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">50</style></volume><pages><style face="normal" font="default" size="100%">536-46</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The Populus euphratica floodplain forests along the lower reaches of the Tarim River in continental-arid Xinjiang (north-west China) have been declining in recent decades as a result of dam constructions and the withdrawal of water from the river. Since 2000, controlled flooding has been carried out to counteract this process of degradation. However, the consequences of a changing water regime for the floodplain ecosystem are not yet sufficiently investigated. In 2004 we sampled a total of 150 P. euphratica trees along two transects at the middle and lower reaches of the Tarim River to compare the age structure and growth of these two tree populations. The anthropogenic drawdown of the groundwater table had no effect on the average growth of the trees at the lower reaches. However, tree growth abruptly increased after controlled flooding, thus showing distinct signs of recovery.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18713421?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lingua, Guido</style></author><author><style face="normal" font="default" size="100%">Franchin, Cinzia</style></author><author><style face="normal" font="default" size="100%">Todeschini, Valeria</style></author><author><style face="normal" font="default" size="100%">Castiglione, Stefano</style></author><author><style face="normal" font="default" size="100%">Biondi, Stefania</style></author><author><style face="normal" font="default" size="100%">Burlando, Bruno</style></author><author><style face="normal" font="default" size="100%">Parravicini, Valerio</style></author><author><style face="normal" font="default" size="100%">Torrigiani, Patrizia</style></author><author><style face="normal" font="default" size="100%">Berta, Graziella</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Arbuscular mycorrhizal fungi differentially affect the response to high zinc concentrations of two registered poplar clones.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">153</style></volume><pages><style face="normal" font="default" size="100%">137-47</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The effects of a high concentration of zinc on two registered clones of poplar (Populus alba Villafranca and Populus nigra Jean Pourtet), inoculated or not with two arbuscular mycorrhizal fungi (Glomus mosseae or Glomus intraradices) before transplanting them into polluted soil, were investigated, with special regard to the extent of root colonization by the fungi, plant growth, metal accumulation in the different plant organs, and leaf polyamine concentration. Zinc accumulation was lower in Jean Pourtet than in Villafranca poplars, and it was mainly translocated to the leaves; the metal inhibited mycorrhizal colonization, compromised plant growth, and, in Villafranca, altered the putrescine profile in the leaves. Most of these effects were reversed or reduced in plants pre-inoculated with G. mosseae. Results indicate that poplars are suitable for phytoremediation purposes, confirming that mycorrhizal fungi can be useful for phytoremediation, and underscore the importance of appropriate combinations of plant genotypes and fungal symbionts.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17888550?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhang, Q</style></author><author><style face="normal" font="default" size="100%">Zhang, Z-Y</style></author><author><style face="normal" font="default" size="100%">Lin, S-Z</style></author><author><style face="normal" font="default" size="100%">Zheng, H-Q</style></author><author><style face="normal" font="default" size="100%">Lin, Y-Z</style></author><author><style face="normal" font="default" size="100%">An, X-M</style></author><author><style face="normal" font="default" size="100%">Li, Y</style></author><author><style face="normal" font="default" size="100%">Li, H-X</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Characterization of resistance gene analogs with a nucleotide binding site isolated from a triploid white poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant biology (Stuttgart, Germany)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Biol (Stuttg)</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">10</style></volume><pages><style face="normal" font="default" size="100%">310-22</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The majority of cloned plant disease resistance genes (R genes) encode a nucleotide binding site (NBS) and a leucine-rich repeat (LRR) domain. In this study, to better understand the R genes in white poplar, 59 resistance gene analogues (RGAs) were identified from a triploid white poplar [(Populus tomentosa x Populus bolleana) x P. tomentosa], based on conserved NBS regions. The 59 RGAs were phylogenetically classified into 10 subfamilies, and 54 RGAs with open-reading frames (ORFs) were further grouped into two classes, toll and interleukin-1 receptor (TIR) and non-TIR. BLAST searches with reference to the genomic sequence of Populus trichocarpa found 96 highly homologous regions distributed in 37 loci, suggesting the abundance and divergence of NBS-encoding genes in the triploid poplar genome. Within subfamilies 1-3, the average non-synonymous/synonymous substitution (omega) rates were &lt; 1, indicating purifying selection on these RGAs, but some sites were clearly under diversifying selection with omega &gt; 1. Many intergenic exchanges were also detected among these RGAs, indicating a probable role in homogenising NBS domains. Quantitative real-time PCR analysis revealed dramatic variations in the transcript level of 18 RGAs in the mature leaves, bark and roots of the triploid poplar, and identified two RGAs that had significantly higher level of transcripts in bark, four RGAs in mature leaves, and 14 in the above-ground portion of poplars, suggesting their probable roles in resistance against diseases attacking the organs. Our results shed light on genetic resources of poplar resistance and will be useful for further resistance gene isolation and exploitation.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18426478?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Li, Xu</style></author><author><style face="normal" font="default" size="100%">Weng, Jing-Ke</style></author><author><style face="normal" font="default" size="100%">Chapple, Clint</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Improvement of biomass through lignin modification.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">54</style></volume><pages><style face="normal" font="default" size="100%">569-81</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Lignin, a major component of the cell wall of vascular plants, has long been recognized for its negative impact on forage quality, paper manufacturing, and, more recently, cellulosic biofuel production. Over the last two decades, genetic and biochemical analyses of brown midrib mutants of maize, sorghum and related grasses have advanced our understanding of the relationship between lignification and forage digestibility. This work has also inspired genetic engineering efforts aimed at generating crops with altered lignin, with the expectation that these strategies would enhance forage digestibility and/or pulping efficiency. The knowledge gained from these bioengineering efforts has greatly improved our understanding of the optimal lignin characteristics required for various applications of lignocellulosic materials while also contributing to our understanding of the lignin biosynthetic pathway. The recent upswing of interest in cellulosic biofuel production has become the new focus of lignin engineering. Populus trichocarpa and Brachypodium distachyon are emerging as model systems for energy crops. Lignin research on these systems, as well as on a variety of proposed energy crop species, is expected to shed new light on lignin biosynthesis and its regulation in energy crops, and lead to rational genetic engineering approaches to modify lignin for improved biofuel production.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18476864?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Flokstra, Brittany R</style></author><author><style face="normal" font="default" size="100%">Van Aken, Benoit</style></author><author><style face="normal" font="default" size="100%">Schnoor, Jerald L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Microtox toxicity test: detoxification of TNT and RDX contaminated solutions by poplar tissue cultures.</style></title><secondary-title><style face="normal" font="default" size="100%">Chemosphere</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Chemosphere</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">71</style></volume><pages><style face="normal" font="default" size="100%">1970-6</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Poplar (Populus deltoidesxnigra DN34) tissue cultures removed 2,4,6-trinitrotoluene (TNT) from an aqueous solution in five days, reducing the toxicity of the solution from highly toxic Microtox EC value to that of the control. 1,3,5-Trinitro-1,3,5-triazacyclohexane (RDX) was taken up by the plant tissue cultures more slowly, but toxicity reduction of the solution was evident. The measurement of toxicity reduction of aqueous solutions containing TNT and RDX was performed using a novel methodology developed for use with the Microtox testing system. Radiolabeled TNT and RDX were used to confirm removal of explosives from hydroponic solutions containing plant tissue cultures and to verify that toxicity did not change in solutions where no plant cultures were present (positive controls). High Performance Liquid Chromatography (HPLC) and Liquid Scintillation Counter (LSC) measurements confirmed removal of TNT and RDX from solutions containing poplar plant tissue cultures and constancy of the plant-free controls. In addition, metabolites were identified in remediated solutions by HPLC, confirming the mechanism by which plants can remediate groundwater, surface water, and soil solutions.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18400248?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gallagher, Frank J</style></author><author><style face="normal" font="default" size="100%">Pechmann, Ildiko</style></author><author><style face="normal" font="default" size="100%">Bogden, John D</style></author><author><style face="normal" font="default" size="100%">Grabosky, Jason</style></author><author><style face="normal" font="default" size="100%">Weis, Peddrick</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Soil metal concentrations and vegetative assemblage structure in an urban brownfield.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">153</style></volume><pages><style face="normal" font="default" size="100%">351-61</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Anthropogenic sources of toxic elements have had serious ecological and human health impacts. Analysis of the soil samples from a brownfield within Liberty State Park, Jersey City, NJ, USA, showed that arsenic, chromium, lead, zinc and vanadium exist at concentrations above those considered ambient for the area. Accumulation and translocation features were characterized for the dominant plant species of four vegetative assemblages. The trees Betula populifolia and Populus deltoides were found to be accumulating Zn in leaf tissue at extremely high levels. B. populifolia, P. deltoides and Rhus copallinum accumulated Cr primarily in the root tissue. A comparison of soil metal maps and vegetative assemblage maps indicates that areas of increasing total soil metal load were dominated by successional northern hardwoods while semi-emergent marshes consisting mostly of endemic species were restricted primarily to areas of low soil metal load.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17900771?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Van Aken, Benoit</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Transgenic plants for phytoremediation: helping nature to clean up environmental pollution.</style></title><secondary-title><style face="normal" font="default" size="100%">Trends in biotechnology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Trends Biotechnol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">26</style></volume><pages><style face="normal" font="default" size="100%">225-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Phytoremediation is the use of plants to clean up environmental pollution. However, detoxification of organic pollutants by plants is often slow, leading to the accumulation of toxic compounds that could be later released into the environment. A recent publication by Doty and colleagues describes the development of transgenic poplars (Populus) overexpressing a mammalian cytochrome P450, a family of enzymes commonly involved in the metabolism of toxic compounds. The engineered plants showed enhanced performance with regards to the metabolism of trichloroethylene and the removal of a range of other toxic volatile organic pollutants, including vinyl chloride, carbon tetrachloride, chloroform and benzene. This work suggests that transgenic plants might be able to contribute to the wider and safer application of phytoremediation.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18353473?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kostiainen, Katri</style></author><author><style face="normal" font="default" size="100%">Kaakinen, Seija</style></author><author><style face="normal" font="default" size="100%">Warsta, Elina</style></author><author><style face="normal" font="default" size="100%">Kubiske, Mark E</style></author><author><style face="normal" font="default" size="100%">Nelson, Neil D</style></author><author><style face="normal" font="default" size="100%">Sober, Jaak</style></author><author><style face="normal" font="default" size="100%">Karnosky, David F</style></author><author><style face="normal" font="default" size="100%">Saranpää, Pekka</style></author><author><style face="normal" font="default" size="100%">Vapaavuori, Elina</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Wood properties of trembling aspen and paper birch after 5 years of exposure to elevated concentrations of CO(2) and O(3).</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">805-13</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We investigated the interactive effects of elevated concentrations of carbon dioxide ([CO(2)]) and ozone ([O(3)]) on radial growth, wood chemistry and structure of five 5-year-old trembling aspen (Populus tremuloides Michx.) clones and the wood chemistry of paper birch (Betula papyrifera Marsh.). Material for the study was collected from the Aspen FACE (free-air CO(2) enrichment) experiment in Rhinelander, WI, where the saplings had been exposed to four treatments: control, elevated [CO(2)] (560 ppm), elevated [O(3)] (1.5 x ambient) and their combination for five growing seasons. Wood properties of both species were altered in response to exposure to the treatments. In aspen, elevated [CO(2)] decreased uronic acids (constituents of, e.g., hemicellulose) and tended to increase stem diameter. In response to elevated [O(3)] exposure, acid-soluble lignin concentration decreased and vessel lumen diameter tended to decrease. Elevated [O(3)] increased the concentration of acetone-soluble extractives in paper birch, but tended to decrease the concentration of these compounds in aspen. In paper birch, elevated [CO(2)] decreased and elevated [O(3)] increased starch concentration. The responses of wood properties to 5 years of fumigation differed from those previously reported after 3 years of fumigation.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18316312?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Coleman, Heather D</style></author><author><style face="normal" font="default" size="100%">Park, Ji-Young</style></author><author><style face="normal" font="default" size="100%">Nair, Ramesh</style></author><author><style face="normal" font="default" size="100%">Chapple, Clint</style></author><author><style face="normal" font="default" size="100%">Mansfield, Shawn D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">RNAi-mediated suppression of p-coumaroyl-CoA 3'-hydroxylase in hybrid poplar impacts lignin deposition and soluble secondary metabolism.</style></title><secondary-title><style face="normal" font="default" size="100%">Proceedings of the National Academy of Sciences of the United States of America</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Proc. Natl. Acad. Sci. U.S.A.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Mar 18</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">105</style></volume><pages><style face="normal" font="default" size="100%">4501-6</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">p-Coumaroyl-CoA 3'-hydroxylase (C3'H) is a cytochrome P450-dependent monooxygenase that catalyzes the 3'-hydroxylation of p-coumaroyl shikimate and p-coumaroyl quinate. We used RNA interference to generate transgenic hybrid poplar suppressed in C3'H expression and analyzed them with respect to transcript abundance, cell wall structure and chemical composition, and soluble metabolite levels. RT-PCR expression profiles confirmed the down-regulation of C3'H in a number of lines, which generally correlated very well with reduced total cell wall lignin content. The most strongly repressed line was chosen for further analysis and compared with the wild-type trees. In-depth characterization revealed that along with the significant decrease in total lignin content, a significant shift in lignin monomer composition was observed, favoring the generation of p-hydroxyphenyl units at the expense of guaiacyl units while the proportion of syringyl moieties remained constant. Suppression of C3'H also resulted in the accumulation of substantial pools of 1-O-p-coumaroyl-beta-d-glucoside and other phenylpropanoid glycosides, and p-coumaroyl shikimate, providing further insight into the role of C3'H in the lignin biosynthetic pathway. The data presented indicate that when down-regulated, C3'H becomes a rate-limiting step in lignin biosynthesis and further support the involvement of hydroxycinnamic acid shikimate esters in the lignin biosynthetic pathway.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18316744?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Igasaki, Tomohiro</style></author><author><style face="normal" font="default" size="100%">Watanabe, Yumiko</style></author><author><style face="normal" font="default" size="100%">Nishiguchi, Mitsuru</style></author><author><style face="normal" font="default" size="100%">Kotoda, Nobuhiro</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The FLOWERING LOCUS T/TERMINAL FLOWER 1 family in Lombardy poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant &amp; cell physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">49</style></volume><pages><style face="normal" font="default" size="100%">291-300</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Genes in the FLOWERING LOCUS T (FT) and TERMINAL FLOWER 1 (TFL1) family have been shown to be important in the control of the switch between vegetative and reproductive growth in several plant species. We isolated nine members of the FT/TFL1 family from Lombardy poplar (Populus nigra var. italica Koehne). Sequence analysis of the members of the FT/TFL1 family revealed considerable homology within their coding regions both among family members and to the members of the same family in Arabidopsis, tomato and grapevine. Moreover, members of this family in all four species examined display a common exon-intron organization. Phylogenetic analysis revealed that the genes fall into four different clades: two into the TFL1 clade; five into the FT clade; and one each into the MOTHER OF FT AND TFL1 and BROTHER OF FT AND TFL1 clades. One gene in the TFL1 clade, PnTFL1, is expressed in vegetative meristems, and transgenic Arabidopsis that ectopically expressed PnTFL1 had a late-flowering phenotype. The expression patterns of two genes in the FT clade, PnFT1 and PnFT2, suggested a role for them in the promotion of flowering, and transgenic Arabidopsis that ectopically expressed either PnFT1 or PnFT2 had an early-flowering phenotype.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18203732?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Major, Ian T</style></author><author><style face="normal" font="default" size="100%">Constabel, C Peter</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Functional analysis of the Kunitz trypsin inhibitor family in poplar reveals biochemical diversity and multiplicity in defense against herbivores.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">146</style></volume><pages><style face="normal" font="default" size="100%">888-903</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We investigated the functional and biochemical variability of Kunitz trypsin inhibitor (KTI) genes of Populus trichocarpa x Populus deltoides. Phylogenetic analysis, expressed sequence tag databases, and western-blot analysis confirmed that these genes belong to a large and diverse gene family with complex expression patterns. Five wound- and herbivore-induced genes representing the diversity of the KTI gene family were selected for functional analysis and shown to produce active KTI proteins in Escherichia coli. These recombinant KTI proteins were all biochemically distinct and showed clear differences in efficacy against trypsin-, chymotrypsin-, and elastase-type proteases, suggesting functional specialization of different members of this gene family. The in vitro stability of the KTIs in the presence of reducing agents and elevated temperature also varied widely, emphasizing the biochemical differences of these proteins. Significantly, the properties of the recombinant KTI proteins were not predictable from primary amino acid sequence data. Proteases in midgut extracts of Malacosoma disstria, a lepidopteran pest of Populus, were strongly inhibited by at least two of the KTI gene products. This study suggests that the large diversity in the poplar (Populus spp.) KTI family is important for biochemical and functional specialization, which may be important in the maintenance of pest resistance in long-lived plants such as poplar.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18024557?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Yin, Tongming</style></author><author><style face="normal" font="default" size="100%">Difazio, Stephen P</style></author><author><style face="normal" font="default" size="100%">Gunter, Lee E</style></author><author><style face="normal" font="default" size="100%">Zhang, Xinye</style></author><author><style face="normal" font="default" size="100%">Sewell, Michell M</style></author><author><style face="normal" font="default" size="100%">Woolbright, Scott A</style></author><author><style face="normal" font="default" size="100%">Allan, Gery J</style></author><author><style face="normal" font="default" size="100%">Kelleher, Collin T</style></author><author><style face="normal" font="default" size="100%">Douglas, Carl J</style></author><author><style face="normal" font="default" size="100%">Wang, Mingxiu</style></author><author><style face="normal" font="default" size="100%">Tuskan, Gerald A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genome structure and emerging evidence of an incipient sex chromosome in Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">Genome research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Genome Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">18</style></volume><pages><style face="normal" font="default" size="100%">422-30</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The genus Populus consists of dioecious woody species with largely unknown genetic mechanisms for gender determination. We have discovered genetic and genomic features in the peritelomeric region of chromosome XIX that suggest this region of the Populus genome is in the process of developing characteristics of a sex chromosome. We have identified a gender-associated locus that consistently maps to this region. Furthermore, comparison of genetic maps across multiple Populus families reveals consistently distorted segregation within this region. We have intensively characterized this region using an F(1) interspecific cross involving the female genotype that was used for genome sequencing. This region shows suppressed recombination and high divergence between the alternate haplotypes, as revealed by dense map-based genome assembly using microsatellite markers. The suppressed recombination, distorted segregation, and haplotype divergence were observed only for the maternal parent in this cross. Furthermore, the progeny of this cross showed a strongly male-biased sex ratio, in agreement with Haldane's rule that postulates that the heterogametic sex is more likely to be absent, rare, or sterile in interspecific crosses. Together, these results support the role of chromosome XIX in sex determination and suggest that sex determination in Populus occurs through a ZW system in which the female is the heterogametic gender.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18256239?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Balestrazzi, Alma</style></author><author><style face="normal" font="default" size="100%">Bonadei, Martina</style></author><author><style face="normal" font="default" size="100%">Zelasco, Samanta</style></author><author><style face="normal" font="default" size="100%">Quattrini, Emanuele</style></author><author><style face="normal" font="default" size="100%">Calvio, Cinzia</style></author><author><style face="normal" font="default" size="100%">Galizzi, Alessandro</style></author><author><style face="normal" font="default" size="100%">Carbonera, Daniela</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Recovery of useful traits from isolates inhabiting an agricultural soil cultivated with herbicide-resistant poplars.</style></title><secondary-title><style face="normal" font="default" size="100%">Canadian journal of microbiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Can. J. Microbiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">54</style></volume><pages><style face="normal" font="default" size="100%">201-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The aim of this study was to investigate the culturable bacteria living in soil cultivated with Basta-tolerant transgenic white poplars (Populus alba L. 'Villafranca'). Plate Count Agar medium containing phosphinothricin, the active component of Basta, was used to isolate the herbicide-resistant bacteria (HRB). No significant changes in the size of the soil microbial flora following herbicide treatment were observed. The characterization of HRB isolates by 16S rDNA-based taxonomy revealed a predominance of Pseudomonas and Bacillus species. The screening carried out on soil samples allowed for the recovery of isolates with useful properties for biotechnological and agronomical purposes, particularly in relation to root development. Among the tested isolates, only HRB-1b, HRB-1c, and HRB-7 showed remarkable swarming ability, a valuable trait supporting the beneficial plant-microbe interactions. HRB-1c was also characterized by consistent production of indoleacetic acid (17.8 +/- 0.09 microg x mL-1 x (OD600 unit)-1), and it was able to stimulate the in vitro growth of Villafranca explants. Since novel tools are constantly required to enhance productivity of perennial species and to expand their use for practical purposes, the availability of bacteria that support tree growth, such as the HRB-1c isolate, represents a significant advantage.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18388991?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Domínguez, María T</style></author><author><style face="normal" font="default" size="100%">Marañón, Teodoro</style></author><author><style face="normal" font="default" size="100%">Murillo, José M</style></author><author><style face="normal" font="default" size="100%">Schulin, Rainer</style></author><author><style face="normal" font="default" size="100%">Robinson, Brett H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Trace element accumulation in woody plants of the Guadiamar Valley, SW Spain: a large-scale phytomanagement case study.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">152</style></volume><pages><style face="normal" font="default" size="100%">50-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Phytomanagement employs vegetation and soil amendments to reduce the environmental risk posed by contaminated sites. We investigated the distribution of trace elements in soils and woody plants from a large phytomanaged site, the Guadiamar Valley (SW Spain), 7 years after a mine spill, which contaminated the area in 1998. At spill-affected sites, topsoils (0-25 cm) had elevated concentrations of As (129 mg kg(-1)), Bi (1.64 mg kg(-1)), Cd (1.44 mg kg(-1)), Cu (115 mg kg(-1)), Pb (210 mg kg(-1)), Sb (13.8 mg kg(-1)), Tl (1.17 mg kg(-1)) and Zn (457 mg kg(-1)). Trace element concentrations in the studied species were, on average, within the normal ranges for higher plants. An exception was white poplar (Populus alba), which accumulated Cd and Zn in leaves up to 3 and 410 mg kg(-1) respectively. We discuss the results with regard to the phytomanagement of trace element contaminated sites.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17602809?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Park, Sunchung</style></author><author><style face="normal" font="default" size="100%">Keathley, Daniel E</style></author><author><style face="normal" font="default" size="100%">Han, Kyung-Hwan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Transcriptional profiles of the annual growth cycle in Populus deltoides.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">321-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Cycling between vegetative growth and dormancy is an important adaptive mechanism in temperate woody plants. To gain insights into the underlying molecular mechanisms, we carried out global transcription analyses on stem samples from poplar (Populus deltoides Bartr. ex Marsh.) trees grown in the field and in controlled environments. Among seasonal changes in the transcriptome, up-regulation of defense-related genes predominated in early winter, whereas signaling-related genes were up-regulated during late winter. Cluster analysis of the differentially expressed genes showed that plants regulated seasonal growth by integrating environmental factors with development. Short day lengths induced some cold-associated genes without concomitant low temperature exposure, and enhanced the expression of some genes when combined with low temperature exposure. These mechanisms appear to maintain closer synchrony between cold hardiness and climate than would be achieved through responses to temperature alone.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18171656?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Abreu, S N</style></author><author><style face="normal" font="default" size="100%">Soares, A M V M</style></author><author><style face="normal" font="default" size="100%">Nogueira, A J A</style></author><author><style face="normal" font="default" size="100%">Morgado, F</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Tree rings, Populus nigra L., as mercury data logger in aquatic environments: case study of an historically contaminated environment.</style></title><secondary-title><style face="normal" font="default" size="100%">Bulletin of environmental contamination and toxicology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bull Environ Contam Toxicol</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">80</style></volume><pages><style face="normal" font="default" size="100%">294-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In this study, a tree (Populus nigra L.) has been presented as data logger of mercury release in aquatic environments using tree rings chemistry to provide chronological historical monitoring of mercury discharge from a chlor-alkali industrial effluent to a coastal lagoon. Tree rings (Populus nigra L.) as mercury data logger is suggested by mercury accumulation trends in the tree rings reflecting the industrial plant capacity increments in the early stages of mercury discharges and enhancing industrial plant controls to minimize mercury discharges in the last two decades after imposed global regulations on mercury emissions.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18299785?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kramer, Eric M</style></author><author><style face="normal" font="default" size="100%">Lewandowski, Michael</style></author><author><style face="normal" font="default" size="100%">Beri, Satvik</style></author><author><style face="normal" font="default" size="100%">Bernard, Jessica</style></author><author><style face="normal" font="default" size="100%">Borkowski, Matthew</style></author><author><style face="normal" font="default" size="100%">Borkowski, Michael H</style></author><author><style face="normal" font="default" size="100%">Burchfield, Laura Ann</style></author><author><style face="normal" font="default" size="100%">Mathisen, Brenda</style></author><author><style face="normal" font="default" size="100%">Normanly, Jennifer</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Auxin gradients are associated with polarity changes in trees.</style></title><secondary-title><style face="normal" font="default" size="100%">Science (New York, N.Y.)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Science</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jun 20</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">320</style></volume><pages><style face="normal" font="default" size="100%">1610</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Models of plant growth and development propose that changes in cell polarity are mediated by gradients of the plant hormone auxin. With use of gas chromatography-mass spectrometry, we measured the redistribution of endogenous auxin in stems of quaking aspen trees (Populus tremuloides) after wounding. Persistent (lasting at least 24 hours) auxin gradients were observed in the region of the cambium where cell polarity was changing. A computer model of the auxin redistribution shows agreement with measured concentrations.</style></abstract><issue><style face="normal" font="default" size="100%">5883</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18566279?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Caruso, Aurore</style></author><author><style face="normal" font="default" size="100%">Chefdor, Françoise</style></author><author><style face="normal" font="default" size="100%">Carpin, Sabine</style></author><author><style face="normal" font="default" size="100%">Depierreux, Christiane</style></author><author><style face="normal" font="default" size="100%">Delmotte, Francis M</style></author><author><style face="normal" font="default" size="100%">Kahlem, Guy</style></author><author><style face="normal" font="default" size="100%">Morabito, Domenico</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Physiological characterization and identification of genes differentially expressed in response to drought induced by PEG 6000 in Populus canadensis leaves.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jun 16</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">165</style></volume><pages><style face="normal" font="default" size="100%">932-41</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We report here about the physiological and molecular responses of Populus canadensis (clone Dorskamp) to drought. The stress was applied to young rooted cuttings by PEG 6000 application over 30 days. This stress induces a decrease in predawn leaf water potential. After 10 days of stress, there was a decrease in stomatal conductance and a slight retardation of leaf growth, but the osmotic potential remained constant. Using the differential display technique, we searched for genes differentially expressed in response to drought at this date. Thirty-six differentially expressed leaf cDNAs were detected between stressed and control conditions. Thirty-four cDNAs clones were successfully cloned and 23 were found to share high identity with Arabidopsis thaliana and Populus trichocarpa genes. The transcriptional regulation of 21 genes was examined by reverse RNA dot blot, confirming an increase in expression for 16 of them after 10 days of treatment. Among these 16 genes, most of them are involved in a different cellular metabolic pathway. These differentially expressed genes are also involved and/or regulated by other treatments such as salt, withholding water or auxin application. The maintenance of growth observed during the first 10 days of the stress period could be due to the regulation of these genes and can be a common response between herbaceous plants and trees.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17928100?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Boschi-Muller, Sandrine</style></author><author><style face="normal" font="default" size="100%">Gand, Adeline</style></author><author><style face="normal" font="default" size="100%">Branlant, Guy</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The methionine sulfoxide reductases: Catalysis and substrate specificities.</style></title><secondary-title><style face="normal" font="default" size="100%">Archives of biochemistry and biophysics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Arch. Biochem. Biophys.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jun 15</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">474</style></volume><pages><style face="normal" font="default" size="100%">266-73</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Oxidation of Met residues in proteins leads to the formation of methionine sulfoxides (MetSO). Methionine sulfoxide reductases (Msr) are ubiquitous enzymes, which catalyze the reduction of the sulfoxide function of the oxidized methionine residues. In vivo, the role of Msrs is described as essential in protecting cells against oxidative damages and to play a role in infection of cells by pathogenic bacteria. There exist two structurally-unrelated classes of Msrs, called MsrA and MsrB, with opposite stereoselectivity towards the S and R isomers of the sulfoxide function, respectively. Both Msrs present a similar three-step catalytic mechanism. The first step, called the reductase step, leads to the formation of a sulfenic acid on the catalytic Cys with the concomitant release of Met. In recent years, significant efforts have been made to characterize structural and molecular factors involved in the catalysis, in particular of the reductase step, and in structural specificities.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18302927?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ma, Hao</style></author><author><style face="normal" font="default" size="100%">Difazio, Stephen</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">An efficient method for purification of PCR products for sequencing.</style></title><secondary-title><style face="normal" font="default" size="100%">BioTechniques</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BioTechniques</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">44</style></volume><pages><style face="normal" font="default" size="100%">921-3</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A high-throughput DNA sequencing method that generated high quality data was developed. A frame fashioned from a standard agarose gel combined with 0.1%-0.2% low-melting point (LMP) agarose gel was used to isolate the PCR product of interest. Collected PCR products were centrifuged without any reagents and the supernatants were directly used for a sequencing reaction. This method is simple and labor efficient, provides high quality sequences at a low cost, and bypasses problems with impure PCR products. This technique has been used for single nucleotide polymorphism (SNP) discovery in Populus angustifolia trees.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18533902?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Joss, B N</style></author><author><style face="normal" font="default" size="100%">Hall, R J</style></author><author><style face="normal" font="default" size="100%">Sidders, D M</style></author><author><style face="normal" font="default" size="100%">Keddy, T J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Fuzzy-logic modeling of land suitability for hybrid poplar across the Prairie Provinces of Canada.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental monitoring and assessment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ Monit Assess</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">141</style></volume><pages><style face="normal" font="default" size="100%">79-96</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Determining the feasibility of a large-scale afforestation program is one approach being investigated by the Government of Canada to increase Canada's potential to sequester carbon from the atmosphere. Large-scale afforestation, however, requires knowledge of where it is suitable to establish and grow trees. Spatial models based on Boolean logic and/or statistical models within a geographic information system may be used for this purpose, but empirical environmental data are often lacking, and the association of these data to land suitability is most often a subjective process. As a solution to this problem, this paper presents a fuzzy-logic modeling approach to assess land suitability for afforestation of hybrid poplar (Populus spp.) over the Prairie Provinces of Canada. Expert knowledge regarding the selection and magnitudes of environmental variables were integrated into fuzzy rule sets from which estimates of land suitability were generated and presented in map form. The environmental variables selected included growing season precipitation, climate moisture index, growing degree days, and Canada Land Inventory capability for agriculture and elevation. Approximately 150,000 km2, or 28% of the eligible land base within the Prairie Provinces was found to be suitable for afforestation. Accuracy assessments conducted with fuzzy accuracy methods provided a more descriptive assessment of the resulting land suitability map than figures generated from a more conventional Boolean-based accuracy measure. Modeling, mapping and accuracy assessment issues were identified for future extension of this work to map hybrid poplar land suitability over Canada.</style></abstract><issue><style face="normal" font="default" size="100%">1-3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17674133?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wang, Ruigang</style></author><author><style face="normal" font="default" size="100%">Chen, Shaoliang</style></author><author><style face="normal" font="default" size="100%">Zhou, Xiaoyang</style></author><author><style face="normal" font="default" size="100%">Shen, Xin</style></author><author><style face="normal" font="default" size="100%">Deng, Lin</style></author><author><style face="normal" font="default" size="100%">Zhu, Huijuan</style></author><author><style face="normal" font="default" size="100%">Shao, Jie</style></author><author><style face="normal" font="default" size="100%">Shi, Yong</style></author><author><style face="normal" font="default" size="100%">Dai, Songxiang</style></author><author><style face="normal" font="default" size="100%">Fritz, Eberhard</style></author><author><style face="normal" font="default" size="100%">Hüttermann, Aloys</style></author><author><style face="normal" font="default" size="100%">Polle, Andrea</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Ionic homeostasis and reactive oxygen species control in leaves and xylem sap of two poplars subjected to NaCl stress.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">947-57</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We investigated the effects of increasing soil NaCl concentration on intracellular compartmentalization of salt and on the activities of antioxidant enzymes (superoxide dismutase (SOD), ascorbic peroxidase (APX), catalase (CAT) and glutathione reductase (GR)) and their role in the regulation of reactive oxygen species (ROS; O(2)(-*) and H(2)O(2)) in leaves and xylem sap of salt-tolerant Populus euphratica Oliv. and salt-sensitive P. popularis cv. 35-44. Mesophyll cells of P. euphratica exhibited a high capacity for NaCl exclusion and compartmentalization of salt in vacuoles compared with P. popularis. In P. popularis, the salt treatment resulted in large accumulations of Na(+) and Cl(-) in leaves that induced significant increases in O(2)(-*) and H(2)O(2) production despite marked increases in the activities of antioxidant enzymes in leaves and xylem sap. Separation of the isoforms of leaf SOD, APX and CAT by polyacrylamide gel electrophoresis followed by in-gel activity staining revealed that the salt-induced activities of APX and CAT were the result of increases in activities of all the isoenzymes. Leaf injury and shedding of aged leaves occurred following the oxidative burst in P. popularis, indicating that the increased activities of antioxidant enzymes in P. popularis were insufficient to counter the harmful effects of ROS at high soil NaCl concentrations. Unlike P. popularis plants, P. euphratica plants did not exhibit an oxidative burst in response to the NaCl treatments, because of (1) a high salt exclusion capacity and effective compartmentalization of salt in vacuoles, and (2) up-regulation of antioxidant enzymatic activities after the onset of salt stress. We conclude that P. euphratica plants subjected to saline conditions control ROS homeostasis through two pathways: (1) by maintaining cellular ionic homeostasis and thereby limiting the NaCl-induced enhancement of ROS production under long-term saline conditions; and (2) by rapidly up-regulating antioxidant defenses to prevent oxidative damage.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18381275?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhang, Bingyu</style></author><author><style face="normal" font="default" size="100%">Su, Xiaohua</style></author><author><style face="normal" font="default" size="100%">Zhou, Xiangming</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A MADS-box gene of Populus deltoides expressed during flower development and in vegetative organs.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">929-34</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A MADS-box gene (PdPI) was isolated from a cDNA library constructed from male flower buds of Populus deltoides Bartr. ex Marsh. According to an analysis of genomic DNA structure and putative protein structure, and a phylogenetic study, PdPI is an ortholog of the Arabidopsis PI gene. Relative-quantitative real-time polymerase chain reaction analysis showed that PdPI has a broader expression pattern than PI in Arabidopsis. PdPI was strongly expressed in floral buds and roots and weakly expressed in immature xylem, leaves and apical buds of the male P. deltoides tree. In male inflorescences, PdPI expression was abundant in the perianth and anther, and weak in the peduncle and mature pollen. The large differences in PdPI expression at various phases of male floral bud development were closely related to the development of flower organs (perianth and stamen) and pollen. PdPI was also expressed in female inflorescences. Our results suggest that PdPI has multiple functions in the development of P. deltoides.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18381273?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hartati, Sri</style></author><author><style face="normal" font="default" size="100%">Sudarmonowati, Enny</style></author><author><style face="normal" font="default" size="100%">Park, Yong Woo</style></author><author><style face="normal" font="default" size="100%">Kaku, Tomomi</style></author><author><style face="normal" font="default" size="100%">Kaida, Rumi</style></author><author><style face="normal" font="default" size="100%">Baba, Kei'ichi</style></author><author><style face="normal" font="default" size="100%">Hayashi, Takahisa</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Overexpression of poplar cellulase accelerates growth and disturbs the closing movements of leaves in sengon.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">147</style></volume><pages><style face="normal" font="default" size="100%">552-61</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In this study, poplar (Populus alba) cellulase (PaPopCel1) was overexpressed in a tropical Leguminosae tree, sengon (Paraserianthes falcataria), by the Agrobacterium tumefaciens method. PaPopCel1 overexpression increased the length and width of stems with larger leaves, which showed a moderately higher density of green color than leaves of the wild type. The pairs of leaves on the transgenic plants closed more slowly during sunset than those on the wild-type plants. When main veins from each genotype were excised and placed on a paper towel, however, the leaves of the transgenic plants closed more rapidly than those of the wild-type plant. Based on carbohydrate analyses of cell walls, the leaves of the transgenic plants contained less wall-bound xyloglucan than those of the wild-type plants. In situ xyloglucan endotransglucosylase activity showed that the incorporation of whole xyloglucan, potentially for wall tightening, occurred in the parenchyma cells (motor cells) of the petiolule pulvinus attached to the main vein, although the transgenic plant incorporated less whole xyloglucan than the wild-type plant. These observations support the hypothesis that the paracrystalline sites of cellulose microfibrils are attacked by poplar cellulase, which loosens xyloglucan intercalation, resulting in an irreversible wall modification. This process could be the reason why the overexpression of poplar cellulase both promotes plant growth and disturbs the biological clock of the plant by altering the closing movements of the leaves of the plant.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18417637?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kieffer, Pol</style></author><author><style face="normal" font="default" size="100%">Dommes, Jacques</style></author><author><style face="normal" font="default" size="100%">Hoffmann, Lucien</style></author><author><style face="normal" font="default" size="100%">Hausman, Jean-François</style></author><author><style face="normal" font="default" size="100%">Renaut, Jenny</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Quantitative changes in protein expression of cadmium-exposed poplar plants.</style></title><secondary-title><style face="normal" font="default" size="100%">Proteomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Proteomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">8</style></volume><pages><style face="normal" font="default" size="100%">2514-30</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Cadmium (Cd) pollution is a worldwide major concern having, among others, deleterious effects on plants. In the present work, the effects of a 20 microM Cd exposure in hydroponics culture during 14 days were evaluated in young poplar leaves. Proteins were analysed by 2-D DIGE, followed by MALDI-TOF-TOF identification. Additionally, growth and other physiological parameters were monitored during the experiment. Treated plants exhibited an inhibition of growth and visual symptoms appeared after 7 days. A significant accumulation of Cd in all organs was recorded by ICP-MS analysis. A number of changes in the expression of proteins with various functions were identified; in particular a decreased abundance of oxidative stress regulating proteins, whereas pathogenesis-related proteins showed a drastic increase in abundance. Furthermore, a large number of proteins involved in carbon metabolism showed a decrease in abundance, while proteins involved in remobilizing carbon from other energy sources were upregulated. In conclusion, the negative effect of Cd could be explained by a deleterious effect on protein expression from the primary carbon metabolism and from the oxidative stress response mechanism. Accumulation of Cd in stems of poplar, coupled with a low impact of Cd on physiological parameters, promotes the use of poplar trees for phytoremediation purposes.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18563750?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Frey, Beat</style></author><author><style face="normal" font="default" size="100%">Pesaro, Manuel</style></author><author><style face="normal" font="default" size="100%">Rüdt, Andreas</style></author><author><style face="normal" font="default" size="100%">Widmer, Franco</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Resilience of the rhizosphere Pseudomonas and ammonia-oxidizing bacterial populations during phytoextraction of heavy metal polluted soil with poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental microbiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Microbiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">10</style></volume><pages><style face="normal" font="default" size="100%">1433-49</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We assessed the effects of phytoextraction on the dynamics of Pseudomonas spp. and ammonia-oxidizing bacterial populations in a heavy metal (HM) polluted soil. Hybrid poplars were grown in two-compartment root containers with a medium history (&gt; 4 years) of HM pollution for 13 weeks. Bulk and poplar rhizosphere soils were analysed by denaturing gradient gel electrophoresis (DGGE) of Pseudomonas (sensu stricto) 16S rRNA and amoA gene fragments. DGGE patterns revealed that Pseudomonas and amoA-containing populations in the contaminated soils were markedly different from those in the uncontaminated soils. Pseudomonas and amoA profiles appeared to be stable over time in the bulk soils. In contrast, contaminated rhizosphere soils revealed a clear shift of populations with removal of HM becoming similar or at least shifted to the populations of the uncontaminated soils. The effect of phytoextraction was, however, not evident in the bulk samples, which still contained large amounts of HM. Cloning and sequencing of dominant DGGE bands revealed that Pseudomonas were phylogenetically related to the Pseudomonas fluorescens cluster and the amoA sequences to Nitrosospira spp. At the last sampling, major prominent band sequences from contaminated rhizosphere soils were identical to sequences obtained from uncontaminated rhizosphere soils, indicating that the populations were dominated by the same phylotypes. This study suggests that two taxonomically different populations are able to recover after the relief of HM stress by phytoextraction practices, whereas bulk microbial activities still remained depressed.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18279346?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bond, J</style></author><author><style face="normal" font="default" size="100%">Donaldson, L</style></author><author><style face="normal" font="default" size="100%">Hill, S</style></author><author><style face="normal" font="default" size="100%">Hitchcock, K</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Safranine fluorescent staining of wood cell walls.</style></title><secondary-title><style face="normal" font="default" size="100%">Biotechnic &amp; histochemistry : official publication of the Biological Stain Commission</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biotech Histochem</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">83</style></volume><pages><style face="normal" font="default" size="100%">161-71</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Safranine is an azo dye commonly used for plant microscopy, especially as a stain for lignified tissues such as xylem. Safranine fluorescently labels the wood cell wall, producing green/yellow fluorescence in the secondary cell wall and red/orange fluorescence in the middle lamella (ML) region. We examined the fluorescence behavior of safranine under blue light excitation using a variety of wood- and fiber-based samples of known composition to interpret the observed color differentiation of different cell wall types. We also examined the basis for the differences in fluorescence emission using spectral confocal microscopy to examine lignin-rich and cellulose-rich cell walls including reaction wood and decayed wood compared to normal wood. Our results indicate that lignin-rich cell walls, such as the ML of tracheids, the secondary wall of compression wood tracheids, and wood decayed by brown rot, tend to fluoresce red or orange, while cellulose-rich cell walls such as resin canals, wood decayed by white rot, cotton fibers and the G-layer of tension wood fibers, tend to fluoresce green/yellow. This variation in fluorescence emission seems to be due to factors including an emission shift toward red wavelengths combined with dye quenching at shorter wavelengths in regions with high lignin content. Safranine fluorescence provides a useful way to differentiate lignin-rich and cellulose-rich cell walls without counterstaining as required for bright field microscopy.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18802812?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Xu, Xiao</style></author><author><style face="normal" font="default" size="100%">Yang, Fan</style></author><author><style face="normal" font="default" size="100%">Xiao, Xiangwen</style></author><author><style face="normal" font="default" size="100%">Zhang, Sheng</style></author><author><style face="normal" font="default" size="100%">Korpelainen, Helena</style></author><author><style face="normal" font="default" size="100%">Li, Chunyang</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Sex-specific responses of Populus cathayana to drought and elevated temperatures.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">31</style></volume><pages><style face="normal" font="default" size="100%">850-60</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Dioecious plant species represent an important component of terrestrial ecosystems. Yet, little is known about sex-specific responses to drought and elevated temperatures. Populus cathayana Rehd, which is a dioecious, deciduous tree species, widely distributed in the northern, central and southwestern regions of China, was employed as a model species in our study. In closed-top chamber experiments, sex-specific morphological, physiological and biochemical responses of P. cathayana to drought and different elevated temperatures were investigated. Compared with the controls, drought significantly decreased the growth and the net photosynthesis rate (A), and increased the intrinsic water use efficiency (WUE(i)), carbon isotope composition (delta13C), and the malondialdehyde (MDA) and abscisic acid (ABA) contents in droughted plants. In contrast, elevated temperatures significantly promoted the growth and the A, but decreased the WUE(i), delta13C, MDA and ABA contents in well-watered individuals. When compared with males, elevated temperatures induced well-watered females to express a greater increase in the height growth (HG), basal diameter (BD), leaf area (LA), total number of leaves (TNL), dry matter accumulation (DMA) and specific leaf area (SLA), and a lower decrease in the A value, transpiration (E), stomatal conductance (g(s)), MDA and ABA contents, while elevated temperatures induced drought-stressed females to exhibit lower values of HG, BD, LA, TNL, DMA, A, E, g(s) and the intercellular CO2 concentration (C(i)), and higher levels of SLA, WUE(i), delta13C, MDA and ABA contents. Our results indicated that the female individuals of P. cathayana are more responsive and suffer from greater negative effects than do males when grown under environments with increased drought stress and elevated temperature.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18284585?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhu, Li</style></author><author><style face="normal" font="default" size="100%">O'Dwyer, Jonathan P</style></author><author><style face="normal" font="default" size="100%">Chang, Vincent S</style></author><author><style face="normal" font="default" size="100%">Granda, Cesar B</style></author><author><style face="normal" font="default" size="100%">Holtzapple, Mark T</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Structural features affecting biomass enzymatic digestibility.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioresource technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bioresour. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">99</style></volume><pages><style face="normal" font="default" size="100%">3817-28</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The rate and extent of enzymatic hydrolysis of lignocellulosic biomass highly depend on enzyme loadings, hydrolysis periods, and structural features resulting from pretreatments. Furthermore, the influence of one structural feature on biomass digestibility varies with the changes in enzyme loading, hydrolysis period and other structural features as well. In this paper, the effects of lignin content, acetyl content, and biomass crystallinity on the 1-, 6-, and 72-h digestibilities with various enzyme loadings were investigated. To eliminate the cross effects among structural features, selective pretreatment techniques were employed to vary one particular structural feature during a pretreatment, while the other two structural features remained unchanged. The digestibility results showed that lignin content and biomass crystallinity dominated digestibility whereas acetyl content had a lesser effect. Lignin removal greatly enhanced the ultimate hydrolysis extent. Crystallinity reduction, however, tremendously increased the initial hydrolysis rate and reduced the hydrolysis time or the amount of enzyme required to attain high digestibility. To some extent, the effects of structural features on digestibility were interrelated. At short hydrolysis periods, lignin content was not important to digestibility when crystallinity was low. Similarly, at long hydrolysis periods, crystallinity was not important to digestibility when lignin content was low.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17826088?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Mellerowicz, Ewa J</style></author><author><style face="normal" font="default" size="100%">Sundberg, Björn</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Wood cell walls: biosynthesis, developmental dynamics and their implications for wood properties.</style></title><secondary-title><style face="normal" font="default" size="100%">Current opinion in plant biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Curr. Opin. Plant Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">11</style></volume><pages><style face="normal" font="default" size="100%">293-300</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Progress has been made toward understanding the biosynthesis and modifications of the cellulose and the hemicellulose/pectin matrix of woody cell walls (and hence wood properties) by identifying 1600 carbohydrate active enzymes (CAZYmes) in Populus, and pinpointing key candidates involved in various developmental stages of wood formation. Transgenic modifications of primary wall modifying enzymes have demonstrated on the possibility of shaping the dimension of wood cells. Candidates for the biosynthesis of secondary wall matrix have been identified, and the cellulose microfibril angle of wood fibers has been modified. In addition, molecular analysis of the plastic development of wood cell walls has provided further information regarding the mechanisms regulating their structure.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18434240?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ding, Ming-Ming</style></author><author><style face="normal" font="default" size="100%">Huang, Qin-Jun</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Analysis on SNPs linked with wood properties of Populus nigra L. gene resources].</style></title><secondary-title><style face="normal" font="default" size="100%">Yi chuan = Hereditas / Zhongguo yi chuan xue hui bian ji</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Yi Chuan</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">30</style></volume><pages><style face="normal" font="default" size="100%">795-800</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In this study, 115 Populus nigra L. collected from Europe were used as materials. They were detected for SNPs of genes linked with lignin and holocellulose (4CL, PAL and CesA2) by TaqMan technology and correlations between SNPs and wood properties (the wood speciely gravity, fiber length, fiber width, microfibre angle, lignin, holocellulose content and a-Cellulose content) were also studied. results showed that (1) 27 SNPs were obtained in the genes, such as 4CL, PAL and CesA2 associated with lignin synthesis. Among them, 17 SNPs were transition (A-G, C-T), 10 SNPs were transversion (A-C, G-C, G-T, and A-T). (2) Three of the SNPs were discriminated, a significant negative correlation between holocellulose content of four-year old P. nigra and SNP1 was detected, and contribution ratio was 11.11%. SNP2 and SNP3 had no significant correlation with wood properties. (3) Wood properties of various genotypes of SNP1 were significantly different. CC and CT genotype relative to TT genotype had larger holocellulose content. SNP1 would be an efficient marker to choose P. nigra gene resources that have larger holocellulose content.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18550506?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Liu, Jiu-Jun</style></author><author><style face="normal" font="default" size="100%">Fang, Sheng-Zuo</style></author><author><style face="normal" font="default" size="100%">Xie, Bao-Dong</style></author><author><style face="normal" font="default" size="100%">Hao, Juan-Juan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Effects of bio-mulching on rhizosphere soil microbial population, enzyme activity and tree growth in poplar plantation].</style></title><secondary-title><style face="normal" font="default" size="100%">Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ying Yong Sheng Tai Xue Bao</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">19</style></volume><pages><style face="normal" font="default" size="100%">1204-10</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Coriaria nepalensis, Pteridium aquilinum var. latiuscukum, Imperata cylindrical var. major, and Quercus fabric were used as mulching materials to study their effects on the rhizosphere soil microbial population and enzyme activity and the tree growth in poplar plantation. The results showed that after mulching with test materials, the populations of both bacteria and fungi in rhizosphere soil were more than those of the control. Of the mulching materials, I. cylindrical and Q. fabric had the best effect, with the numbers of bacteria and fungi being 23.56 and 1.43 times higher than the control, respectively. The bacterial and fungal populations in rhizosphere soil increased with increasing mulching amount. When the mulching amount was 7.5 kg m(-2), the numbers of bacteria and fungi in rhizosphere soil were 0.5 and 5.14 times higher than the control, respectively. Under bio-mulching, the bacterial and fungal populations in rhizosphere soil had a similar annual variation trend, which was accorded with the annual fluctuation of soil temperature and got to the maximum in July and the minimum in December. The urease and phosphatase activities in rhizosphere soil also increased with increasing mulching amount. As for the effects of different mulching materials on the enzyme activities, they were in the order of C. nepalensis &gt; P. aquilinum &gt; I. cylindrical &gt; Q. fabric. The annual variation of urease and phosphatase activities in rhizosphere soil was similar to that of bacterial and fungal populations, being the highest in July and the lowest in December. Bio-mulching promoted the tree height, DBH, and biomass of poplar trees significantly.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18808009?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhuang, Jing</style></author><author><style face="normal" font="default" size="100%">Cai, Bin</style></author><author><style face="normal" font="default" size="100%">Peng, Ri-He</style></author><author><style face="normal" font="default" size="100%">Zhu, Bo</style></author><author><style face="normal" font="default" size="100%">Jin, Xiao-Feng</style></author><author><style face="normal" font="default" size="100%">Xue, Yong</style></author><author><style face="normal" font="default" size="100%">Gao, Feng</style></author><author><style face="normal" font="default" size="100%">Fu, Xiao-Yan</style></author><author><style face="normal" font="default" size="100%">Tian, Yong-Sheng</style></author><author><style face="normal" font="default" size="100%">Zhao, Wei</style></author><author><style face="normal" font="default" size="100%">Qiao, Yu-Shan</style></author><author><style face="normal" font="default" size="100%">Zhang, Zhen</style></author><author><style face="normal" font="default" size="100%">Xiong, Ai-Sheng</style></author><author><style face="normal" font="default" size="100%">Yao, Quan-Hong</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genome-wide analysis of the AP2/ERF gene family in Populus trichocarpa.</style></title><secondary-title><style face="normal" font="default" size="100%">Biochemical and biophysical research communications</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biochem. Biophys. Res. Commun.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jul 4</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">371</style></volume><pages><style face="normal" font="default" size="100%">468-74</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Populus is a model system for investigating the wood development, crown formation, and disease resistance in perennial plants. AR2/ERF is a large family of transcription factors in plant, encoding transcriptional regulators with a variety of functions involved in the developmental and physiological processes. Here, starting from database of Populus genome, we identified 200 AP2/ERF genes by in silico cloning method using the AP2/ERF conserved domain amino acid sequence of Arabidopsis thaliana as probe. Based on the number of AP2/ERF domains and the function of the genes, those AP2/ERF genes from Populus were classified into four subfamilies named the AP2, DREB, ERF, RAV, and a soloist. Among these genes, the number genes of total AP2/ERF family genes, DREB subfamily, and ERF subfamily from Populus trichocarpa were about 1.4-1.6-fold than those from A. thaliana. The rates were very similar for the putative homologs between Populus and Arabidopsis.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18442469?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Isidorov, V A</style></author><author><style face="normal" font="default" size="100%">Brzozowska, M</style></author><author><style face="normal" font="default" size="100%">Czyzewska, U</style></author><author><style face="normal" font="default" size="100%">Glinka, L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Gas chromatographic investigation of phenylpropenoid glycerides from aspen (Populus tremula L.) buds.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of chromatography. A</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J Chromatogr A</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jul 11</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">1198-1199</style></volume><pages><style face="normal" font="default" size="100%">196-201</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">20 phenylpropenoid glycerides were synthesized by esterification of glycerol by p-coumaric, ferulic and caffeic acids. Main diagnostic ions in mass spectra and linear temperature programmed retention indices (LTPRI) of trimethylsilyl derivatives of these compounds were determined by GC/MS analysis. On the basis of these analytical parameters 39 in various degree substituted phenylpropenoid glycerides were for the first time identified in diethyl ether and ethyl acetate extracts from aspen buds.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18533164?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Michalski, Carmen</style></author><author><style face="normal" font="default" size="100%">Mohagheghi, Hoda</style></author><author><style face="normal" font="default" size="100%">Nimtz, Manfred</style></author><author><style face="normal" font="default" size="100%">Pasteels, Jacques</style></author><author><style face="normal" font="default" size="100%">Ober, Dietrich</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Salicyl alcohol oxidase of the chemical defense secretion of two chrysomelid leaf beetles. Molecular and functional characterization of two new members of the glucose-methanol-choline oxidoreductase gene family.</style></title><secondary-title><style face="normal" font="default" size="100%">The Journal of biological chemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Biol. Chem.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jul 11</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">283</style></volume><pages><style face="normal" font="default" size="100%">19219-28</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Salicyl alcohol oxidase is an extracellular enzyme that occurs in glandular reservoirs of chrysomelid leaf beetle larvae and catalyzes the formation of salicylaldehyde, a volatile deterrent used by the larvae against predators. Salicyl alcohol is the hydrolysis product of salicin, a plant-derived precursor taken up by the beetle larvae from the leaves of willow and poplar trees. The cDNA encoding salicyl alcohol oxidase from two related species Chrysomela tremulae and Chrysomela populi has been identified, cloned, and expressed in an active form in Escherichia coli. The open reading frame of 623 amino acids begins in both enzymes with an N-terminal signal peptide of 21 amino acids. Sequence comparison has revealed that salicyl alcohol oxidase belongs to the family of glucose-methanol-choline oxidoreductase-like sequences with mostly unknown function. Enzymes of this family share similar overall structure with an essentially identical FAD-binding site but possess different catalytic activities. The data suggest that salicyl alcohol oxidase, essential for the activation of the plant-derived precursor salicin, was originally recruited from an oxidase involved in the autogenous biosynthesis of iridoid monoterpenes and found in related chrysomelid leaf beetle species.</style></abstract><issue><style face="normal" font="default" size="100%">28</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18482980?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Baek, Jong-Min</style></author><author><style face="normal" font="default" size="100%">Han, Paul</style></author><author><style face="normal" font="default" size="100%">Iandolino, Alberto</style></author><author><style face="normal" font="default" size="100%">Cook, Douglas R</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Characterization and comparison of intron structure and alternative splicing between Medicago truncatula, Populus trichocarpa, Arabidopsis and rice.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Mol. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">67</style></volume><pages><style face="normal" font="default" size="100%">499-510</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Alignment of transcripts and genome sequences yielded a set of alternatively spliced transcripts in four angiosperm genomes: three dicotyledon species Medicago truncatula (Medicago), Populus trichocarpa (poplar) and Arabidopsis thaliana (Arabidopsis), and the monocotyledon Oryzae sativa (rice). Intron retention was the predominant mode of alternative splicing (AS) in each species, consistent with previous reports for Arabidopsis and rice. We analyzed the structure of 5'-splice junctions and observed commonalities between species. There was dependency of base composition between sites flanking the 5'-splice junction, with the potential to create a subset of splice sites that interact more weakly or strongly than average with U1 snRNA. Such altered nucleotide composition was correlated with splicing fidelity in all four species. For Medicago, poplar and Arabidopsis, but not in rice, alternative splicing was most prevalent for introns with decreased UA content, consistent with lower UA content for monocot introns and potentially reflecting evolved differences in splicing mechanisms. Similarly, the occurrence of AS between transcript Gene Ontology categories was positively correlated between Arabidopsis and Medicago, with no correlation between dicots and rice. Analysis of within-species paralogs and between-species reciprocal best-hit homologs yielded rare cases of potentially conserved AS events. Reverse transcriptase PCR and amplicon sequencing were used to confirm a subset of the in silico-predicted AS events within Medicago, as well as to characterize conserved AS events between Medicago and Arabidopsis.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18438730?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">El Bakouri, Hicham</style></author><author><style face="normal" font="default" size="100%">Morillo, José</style></author><author><style face="normal" font="default" size="100%">Usero, José</style></author><author><style face="normal" font="default" size="100%">Ouassini, Abdelhamid</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Endosulfan sulfate sorption on natural organic substances.</style></title><secondary-title><style face="normal" font="default" size="100%">Water environment research : a research publication of the Water Environment Federation</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Water Environ. Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">80</style></volume><pages><style face="normal" font="default" size="100%">609-16</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">This work proposes a viable remediation method based on the use of natural organic substances (NOSs) that characterize the Mediterranean region to improve the ecological system. A series of experiments, including variable conditions, such as temperature, pH, contact time, and pesticide concentration, were performed to demonstrate the efficiency of endosulfan sulfate removal from water by NOSs. Experimental results showed that the pH and temperature of pesticide solutions negatively affect the adsorption process. The maximum adsorption capacity for a specific initial concentration of endosulfan sulfate (0.5 microg/L) was achieved with Origanum compactum (75%), followed by Cistus ladaniferus and Raphanus raphanistrum (72 and 68%, respectively). The adsorption tests gave very satisfying results and point to the possible application of these supports as a remediation technique to prevent pesticide contamination of aquatic ecosystems.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18710144?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Guidi, Werther</style></author><author><style face="normal" font="default" size="100%">Piccioni, Emiliano</style></author><author><style face="normal" font="default" size="100%">Bonari, Enrico</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Evapotranspiration and crop coefficient of poplar and willow short-rotation coppice used as vegetation filter.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioresource technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bioresour. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">99</style></volume><pages><style face="normal" font="default" size="100%">4832-40</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Ten-day evapotranspiration (ETc) and crop coefficient (k(c)) of willow and poplar SRC used as vegetation filter and grown under fertilised (F) and unfertilised (NF) conditions, were determined for two successive growing seasons using volumetric lysimeters. During the first growing season, total ETc observed was, respectively, 620 (NF)-1190 (F)mm in willow and 590 (NF)-725 (F) in poplar. During the second growing season, ETc showed a general increase, mainly in fertilised lysimeters where it ranged between 890 (NF)-1790 mm (F) in willow and 710 (NF)-1100 mm (NF) in poplar. kc reached in both years its maximum between the end of August and the beginning of September. In 2004 maximum kc ranged from 1.25-2.84 in willow and 1.06-1.90 in poplar, whereas in 2005 it ranged from 1.97-5.30 in willow and 1.71-4.28 in poplar. ETc seemed to be strongly correlated to plant development and mainly dependent on its nutritional status rather than on the differences between the species.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17977718?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Luo, Keming</style></author><author><style face="normal" font="default" size="100%">Harding, Scott A</style></author><author><style face="normal" font="default" size="100%">Tsai, Chung-Jui</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A modified T-vector for simplified assembly of hairpin RNAi constructs.</style></title><secondary-title><style face="normal" font="default" size="100%">Biotechnology letters</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biotechnol. Lett.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">30</style></volume><pages><style face="normal" font="default" size="100%">1271-4</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We describe a modified T-vector, pGFPm-T, for direct cloning of RT-PCR products to generate bidirectional restriction fragments for assembly of hairpin-containing RNAi vectors in the popular pFGC and pGSA binary vector backbone. Green fluorescence protein (GFP) is used as a visual reporter for direct selection of recombinants under UV illumination. The simplified cloning process enables a seamless workflow from candidate gene selection and RT-PCR verification to inverted repeat cloning, using a single pair of gene-specific primers.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18317701?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Letts, Matthew G</style></author><author><style face="normal" font="default" size="100%">Phelan, Colleen A</style></author><author><style face="normal" font="default" size="100%">Johnson, Davin R E</style></author><author><style face="normal" font="default" size="100%">Rood, Stewart B</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Seasonal photosynthetic gas exchange and leaf reflectance characteristics of male and female cottonwoods in a riparian woodland.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">1037-48</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Cottonwoods (Populus spp.) are dioecious phreatophytes of hydrological and ecological importance in riparian woodlands throughout the Northern Hemisphere. In streamside zones of southern Alberta, groundwater and soil water typically decline between May and September. To understand how narrowleaf cottonwoods (Populus angustifolia James) are adapted to this seasonal decrease in water availability, we measured photosynthetic gas exchange, leaf reflectance, chlorophyll fluorescence and stable carbon isotope composition (delta(13)C) in trees growing in the Oldman River valley of southern Alberta during the 2006 growth season. Accompanying the seasonal recession in river flow, groundwater table depth (Z(gw)) declined by 1.6 m, but neither mean daily light-saturated net photosynthetic rate (A(max)) nor stomatal conductance (g(s)) was correlated with this change. Both A(max) and g(s) followed a parabolic seasonal pattern, with July 24 maxima of 15.8 micromol m(-2) s(-1) and 559 mmol m(-2) s(-1), respectively. The early summer rise in A(max) was related to an increase in the chlorophyll pool during leaf development. Peak A(max) coincided with the maximum quantum efficiency of Photosystem II (F(v)/F(m)), chlorophyll index (CI) and scaled photochemical reflectance index (sPRI), but occurred one month after maximum volumetric soil water (theta(v)) and minimum Z(gw). In late summer, A(max) decreased by 30-40% from maximum values, in weak correlation with theta(v) (r(2) = 0.50). Groundwater availability limited late-season water stress, so that there was little variation in mean daily transpiration (E). Decreasing leaf nitrogen (% dry mass), CI, F(v)/F(m) and normalized difference vegetation index (NDVI) were also consistent with leaf aging effects. There was a strong correlation between A(max) and g(s) (r(2) = 0.89), so that photosynthetic water-use efficiency (WUE; A(max)/E) decreased logarithmically with increasing vapor pressure deficit in both males (r(2) = 0.75) and females (r(2) = 0.95). The male:female ratio was unequal (2:1, chi(2) = 16.5, P &lt; 0.001) at the study site, but we found no significant between-sex differences in photosynthetic gas exchange, leaf reflectance or chlorophyll fluorescence that might explain the unequal ratio. Females tended to display lower NDVI than males (P = 0.07), but mean WUE did not differ significantly between males and females (2.1 +/- 0.2 versus 2.5 +/- 0.2 mmol mol(-1)), and delta(13)C remained in the -28.8 to -29.3 per thousand range throughout the growth season, in both sexes. These results demonstrate changes in photosynthetic and water-use characteristics that collectively enable vigorous growth throughout the season, despite seasonal changes in water supply and demand.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18450568?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Canam, Thomas</style></author><author><style face="normal" font="default" size="100%">Mak, Sarah W Y</style></author><author><style face="normal" font="default" size="100%">Mansfield, Shawn D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Spatial and temporal expression profiling of cell-wall invertase genes during early development in hybrid poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">1059-67</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Cell-wall invertase genes are spatially and temporally regulated in several plant species, including Daucus carota L., Lycopersicon esculentum L. and Solanum tuberosum L. However, few studies of cell-wall invertase genes of trees have been conducted, despite the importance of trees as a source of lignocellulosic biopolymers. We identified three putative cell-wall invertase genes in hybrid poplar (Populus alba L. x grandidentata Michx.) that showed higher homology to each other than to cell-wall invertases of other dicotyledonous species, with two of the genes (PaxgINV2 and PaxgINV3) appearing as a genomic tandem repeat. These genes are more similar to each other than to tandemly repeated cell-wall invertases of other plants, perhaps indicating parallel evolution of a duplication event with cell-wall invertases in dicotyledons. Spatial and temporal expression analyses throughout a complete annual cycle indicated that PaxgINV1 and PaxgINV2 are highly regulated in vegetative tissues during three distinct growth phases: early growth, dormancy and post-dormancy. Expression of the third gene (PaxgINV3) appears to be tightly regulated and may represent a floral-specific cell-wall invertase. Of the two genes expressed in vegetative tissues, PaxgINV1 appears to be exclusively involved in processes related to dormancy, whereas PaxgINV2 appears to encode an enzyme involved in phloem unloading and in providing actively growing tissues, such as developing xylem, with the energy and carbon skeletons necessary for respiration and cell wall biosynthesis.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18450570?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lu, Shanfa</style></author><author><style face="normal" font="default" size="100%">Sun, Ying-Hsuan</style></author><author><style face="normal" font="default" size="100%">Chiang, Vincent L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Stress-responsive microRNAs in Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">55</style></volume><pages><style face="normal" font="default" size="100%">131-51</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">MicroRNAs (miRNAs), a group of small non-coding RNAs, have recently become the subject of intense study. They are a class of post-transcriptional negative regulators playing vital roles in plant development and growth. However, little is known about their regulatory roles in the responses of trees to the stressful environments incurred over their long-term growth. Here, we report the cloning of small RNAs from abiotic stressed tissues of Populus trichocarpa (Ptc) and the identification of 68 putative miRNA sequences that can be classified into 27 families based on sequence homology. Among them, nine families are novel, increasing the number of the known Ptc-miRNA families from 33 to 42. A total of 346 targets was predicted for the cloned Ptc-miRNAs using penalty scores of &lt;/=2.5 for mismatched patterns in the miRNA:mRNA duplexes as the criterion. Six of the selected targets were validated experimentally. The expression of a majority of the novel miRNAs was altered in response to cold, heat, salt, dehydration, and mechanical stresses. Microarray analysis of known Ptc-miRNAs identified 19 additional cold stress-responsive Ptc-miRNAs from 14 miRNA gene families. Interestingly, we found that individual miRNAs of a family responded differentially to stress, which suggests that the members of a family may have different functions. These results reveal possible roles for miRNAs in the regulatory networks associated with the long-term growth of tree species and provide useful information for developing trees with a greater level of stress resistance.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18363789?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ouyang, Ying</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Modeling the mechanisms for uptake and translocation of dioxane in a soil-plant ecosystem with STELLA.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of contaminant hydrology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Contam. Hydrol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jan 7</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">95</style></volume><pages><style face="normal" font="default" size="100%">17-29</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Knowledge of mechanisms for uptake, translocation, and accumulation of soil contaminants in plants is essential to successful applications of the phytoremediation technique. Analysis and evaluation of these mechanisms would be greatly facilitated by the availability of a dynamic model that can predict soil contaminant uptake by roots, transport from roots through stems to leaves, and accumulation in plant during the transport process. In this study, a dynamic model for uptake and translocation of contaminants from a soil-plant ecosystem (UTCSP) was developed using the STELLA modeling tool. The structure of UTCSP consists of time-dependent simultaneous upward transport, accumulation, and transpiration of water and contaminants in the soil-plant-atmosphere continuum, which was driven by water potential gradients among soils, roots, stems, leaves, and atmosphere. The UTCSP model was calibrated using the experimental measurements and applied to predict phytoremediation of 1,4-dioxane from a sandy soil by a poplar tree. Simulation results showed that about 20% of 1,4-dioxane was removed from the soil by the poplar tree in 90 days. The simulations further revealed that while the mass of 1,4-dioxane in the poplar tree increased consecutively with time, the rates of water and 1,4-dioxane uptake and translocation in the roots, stems, and leaves have a typical diurnal distribution pattern: increasing during the day and decreasing during the night, resulting from daily variations of plant water potentials that were caused by leaf water transpiration. This study suggests that the UTCSP model is a useful tool for estimating phytoremediation of contaminants in the soil-plant ecosystems.</style></abstract><issue><style face="normal" font="default" size="100%">1-2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17870205?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wiklund, Susanne</style></author><author><style face="normal" font="default" size="100%">Johansson, Erik</style></author><author><style face="normal" font="default" size="100%">Sjöström, Lina</style></author><author><style face="normal" font="default" size="100%">Mellerowicz, Ewa J</style></author><author><style face="normal" font="default" size="100%">Edlund, Ulf</style></author><author><style face="normal" font="default" size="100%">Shockcor, John P</style></author><author><style face="normal" font="default" size="100%">Gottfries, Johan</style></author><author><style face="normal" font="default" size="100%">Moritz, Thomas</style></author><author><style face="normal" font="default" size="100%">Trygg, Johan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Visualization of GC/TOF-MS-based metabolomics data for identification of biochemically interesting compounds using OPLS class models.</style></title><secondary-title><style face="normal" font="default" size="100%">Analytical chemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Anal. Chem.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jan 1</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">80</style></volume><pages><style face="normal" font="default" size="100%">115-22</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Metabolomics studies generate increasingly complex data tables, which are hard to summarize and visualize without appropriate tools. The use of chemometrics tools, e.g., principal component analysis (PCA), partial least-squares to latent structures (PLS), and orthogonal PLS (OPLS), is therefore of great importance as these include efficient, validated, and robust methods for modeling information-rich chemical and biological data. Here the S-plot is proposed as a tool for visualization and interpretation of multivariate classification models, e.g., OPLS discriminate analysis, having two or more classes. The S-plot visualizes both the covariance and correlation between the metabolites and the modeled class designation. Thereby the S-plot helps identifying statistically significant and potentially biochemically significant metabolites, based both on contributions to the model and their reliability. An extension of the S-plot, the SUS-plot (shared and unique structure), is applied to compare the outcome of multiple classification models compared to a common reference, e.g., control. The used example is a gas chromatography coupled mass spectroscopy based metabolomics study in plant biology where two different transgenic poplar lines are compared to wild type. By using OPLS, an improved visualization and discrimination of interesting metabolites could be demonstrated.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18027910?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Weng, Y H</style></author><author><style face="normal" font="default" size="100%">Parker, W H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Adaptive variation in fall cold hardiness of aspen from northwestern Ontario.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">143-50</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We investigated adaptive variation in fall cold hardiness development based on the electrical conductivity of tissue diffusates (EC) among 20 aspen provenances from northwestern Ontario. Provenance accounted for over 40% of the total variation in cold injury for seven dates from September through November in three provenance trials. Principal component analysis was performed to summarize the combinations of results for all sampling sites, dates and temperatures (traits). Principal component (PC)-1 represented fully developed cold hardiness differences among provenances; PC-2 represented differences in the timing of the onset of cold hardiness development; and PC-3 represented a site-related difference in cold hardiness development. Heat sum in early summer and late summer precipitation together were the best predictors of absolute degree of cold hardiness (PC-1), whereas temperatures for mid- to late summer were best for predicting onset of cold hardiness development (PC-2). In a second study, we assessed the efficacy of chlorophyll fluorescence (CF) as a simpler technique for determining the cold hardiness of aspen stem samples. Fall cold hardiness of stem samples of 12 of the original 20 provenances was estimated by CF, and the results were evaluated by a visual scoring (VS) method. Correlations between EC and CF measurements from the two studies were moderately strong based on the extent of cold hardiness in October of each year, but were negative for September dates because of a later onset of cold hardiness in the EC study year. Although the EC and CF methods gave similar cold hardiness values for stem samples from 12 provenances, the CF method may be preferred to the EC or VS method for species with chlorophyllous stems because of its greater ease of use.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17938123?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Nygren, Pekka</style></author><author><style face="normal" font="default" size="100%">Pallardy, Stephen G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Applying a universal scaling model to vascular allometry in a single-stemmed, monopodially branching deciduous tree (Attim's model).</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">1-10</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">West, Brown and Enquist (1999a) modeled vascular plants as a continuously branching hierarchical network of connected links (basic structural units) that ends in a terminal unit, the leaf petiole, at the highest link order (WBE model). We applied the WBE model to study architecture and scaling between links of the water transport system from lateral roots to leafy lateral branches and petioles in Populus deltoides Bartr. ex Marsh. trees growing in an agroforestry system (open-grown trees) and in a dense plantation (stand-grown trees). The architecture of P. deltoides violates two WBE model assumptions: (1) the radii of links formed in a branching point are unequal; and (2) there is no terminal unit situated at the end of a hierarchical network, rather, petioles are situated at any link order greater than 1. Link cross sections were taken at various link orders and morphological levels in roots and shoots of open-grown trees and shoots of stand-grown trees. Scaling of link radii was area-preserving. From roots to branches, vessel diameters were scaled with link order in accordance with a 1/6-power, as predicted by the WBE model indicating general vessel tapering. However, analysis of the data at the morphological level showed that vessel radius decreased intermittently with morphological level rather than continuously between successive link orders. Estimation of total water conductive area in a link is based on conducting area and petiole radius in the WBE model. The estimation failed in P. deltoides, probably because petioles are not a terminal unit. Biomass of stand-grown trees scaled with stem basal radius according to the 3/8-power predicted by the WBE model. Thus, the WBE model adequately described vascular allometry and biomass at the whole-tree level in P. deltoides despite violation of Assumption 1, but failed in predictions where the leaf petiole was used as a terminal unit.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17938108?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ruonala, Raili</style></author><author><style face="normal" font="default" size="100%">Rinne, Päivi L H</style></author><author><style face="normal" font="default" size="100%">Kangasjärvi, Jaakko</style></author><author><style face="normal" font="default" size="100%">van der Schoot, Christiaan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">CENL1 expression in the rib meristem affects stem elongation and the transition to dormancy in Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant cell</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">20</style></volume><pages><style face="normal" font="default" size="100%">59-74</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We investigated the short day (SD)-induced transition to dormancy in wild-type hybrid poplar (Populus tremula x P. tremuloides) and its absence in transgenic poplar overexpressing heterologous PHYTOCHROME A (PHYA). CENTRORADIALIS-LIKE1 (CENL1), a poplar ortholog of Arabidopsis thaliana TERMINAL FLOWER1 (TFL1), was markedly downregulated in the wild-type apex coincident with SD-induced growth cessation. By contrast, poplar overexpressing a heterologous Avena sativa PHYA construct (P35S:AsPHYA), with PHYA accumulating in the rib meristem (RM) and adjacent tissues but not in the shoot apical meristem (SAM), upregulated CENL1 in the RM area coincident with an acceleration of stem elongation. In SD-exposed heterografts, both P35S:AsPHYA and wild-type scions ceased growth and formed buds, whereas only the wild type assumed dormancy and P35S:AsPHYA showed repetitive flushing. This shows that the transition is not dictated by leaf-produced signals but dependent on RM and SAM properties. In view of this, callose-enforced cell isolation in the SAM, associated with suspension of indeterminate growth during dormancy, may require downregulation of CENL1 in the RM. Accordingly, upregulation of CENL1/TFL1 might promote stem elongation in poplar as well as in Arabidopsis during bolting. Together, the results suggest that the RM is particularly sensitive to photoperiodic signals and that CENL1 in the RM influences transition to dormancy in hybrid poplar.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18192437?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Woolbright, S A</style></author><author><style face="normal" font="default" size="100%">DiFazio, S P</style></author><author><style face="normal" font="default" size="100%">Yin, T</style></author><author><style face="normal" font="default" size="100%">Martinsen, G D</style></author><author><style face="normal" font="default" size="100%">Zhang, X</style></author><author><style face="normal" font="default" size="100%">Allan, G J</style></author><author><style face="normal" font="default" size="100%">Whitham, T G</style></author><author><style face="normal" font="default" size="100%">Keim, P</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A dense linkage map of hybrid cottonwood (Populus fremontii x P. angustifolia) contributes to long-term ecological research and comparison mapping in a model forest tree.</style></title><secondary-title><style face="normal" font="default" size="100%">Heredity</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Heredity (Edinb)</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">100</style></volume><pages><style face="normal" font="default" size="100%">59-70</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Cottonwoods are foundation riparian species, and hybridization among species is known to produce ecological effects at levels higher than the population, including effects on dependent species, communities and ecosystems. Because these patterns result from increased genetic variation in key cottonwood traits, novel applications of genetic tools (for example, QTL mapping) could be used to place broad-scale ecological research into a genomic perspective. In addition, linkage maps have been produced for numerous species within the genus, and, coupled with the recent publication of the Populus genome sequence, these maps present a unique opportunity for genome comparisons in a model system. Here, we conducted linkage analyses in order to (1) create a platform for QTL and candidate gene studies of ecologically important traits, (2) create a framework for chromosomal-scale perspectives of introgression in a natural population, and (3) enhance genome-wide comparisons using two previously unmapped species. We produced 246 backcross mapping (BC(1)) progeny by crossing a naturally occurring F(1) hybrid (Populus fremontii x P. angustifolia) to a pure P. angustifolia from the same population. Linkage analysis resulted in a dense linkage map of 541 AFLP and 111 SSR markers distributed across 19 linkage groups. These results compared favorably with other Populus linkage studies, and addition of SSR loci from the poplar genome project provided coarse alignment with the genome sequence. Preliminary applications of the data suggest that our map represents a useful framework for applying genomic research to ecological questions in a well-studied system, and has enhanced genome-wide comparisons in a model tree.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17895905?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gray-Mitsumune, Madoka</style></author><author><style face="normal" font="default" size="100%">Blomquist, Kristina</style></author><author><style face="normal" font="default" size="100%">McQueen-Mason, Simon</style></author><author><style face="normal" font="default" size="100%">Teeri, Tuula T</style></author><author><style face="normal" font="default" size="100%">Sundberg, Björn</style></author><author><style face="normal" font="default" size="100%">Mellerowicz, Ewa J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Ectopic expression of a wood-abundant expansin PttEXPA1 promotes cell expansion in primary and secondary tissues in aspen.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant biotechnology journal</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Biotechnol. J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">6</style></volume><pages><style face="normal" font="default" size="100%">62-72</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Expansins are primary agents inducing cell wall extension, and are therefore obvious targets in biotechnological applications aimed at the modification of cell size in plants. In trees, increased fibre length is a goal of both breeding and genetic engineering programmes. We used an alpha-expansin PttEXPA1 that is highly abundant in the wood-forming tissues of hybrid aspen (Populus tremula L. x P. tremuloides Michx.) to evaluate its role in fibre elongation and wood cell development. PttEXPA1 belongs to Subfamily A of alpha-expansins that have conserved motifs at the N- and C-termini of the mature protein. When PttEXPA1 was over-expressed in aspen, an extract of the cell wall-bound proteins of the transgenic plants exhibited an increased expansin activity on cellulose-xyloglucan composites in vitro, indicating that PttEXPA1 is an active expansin. The transgenic lines exhibited increased stem internode elongation and leaf expansion, and larger cell sizes in the leaf epidermis, indicating that PttEXPA1 protein is capable of increasing the growth of these organs by enhancing cell wall expansion in planta. Wood cell development was also modified in the transgenic lines, but the effects were different for vessel elements and fibres, the two main cell types of aspen wood. PttEXPA1 stimulated fibre, but not vessel element, diameter growth, and marginally increased vessel element length, but did not affect fibre length. The observed differences in responsiveness to expansin of these cell types are discussed in the light of differences in their growth strategies and cell wall composition.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17908207?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Yuan, Kun</style></author><author><style face="normal" font="default" size="100%">Zhang, Bo</style></author><author><style face="normal" font="default" size="100%">Zhang, Yanmei</style></author><author><style face="normal" font="default" size="100%">Cheng, Qiang</style></author><author><style face="normal" font="default" size="100%">Wang, Mingxiu</style></author><author><style face="normal" font="default" size="100%">Huang, Minren</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Identification of differentially expressed proteins in poplar leaves induced by Marssonina brunnea f. sp. Multigermtubi.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of genetics and genomics = Yi chuan xue bao</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J Genet Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">35</style></volume><pages><style face="normal" font="default" size="100%">49-60</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Black spot disease in poplar is a disease of the leaf caused by fungus. The major pathogen is Marssonina brunnea f. sp. multigermtubi. To date, little is known about the molecular mechanism of poplar (M. brunnea) interaction. In order to identify the proteins related to disease resistance and understand its molecular basis, the clone &quot;NL895&quot; (P. euramericana CL&quot;NL895&quot;), which is highly resistant to M. brunnea f. sp. multigermtubi, was used in this study. We used two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS) to identify the proteins in poplar leaves that were differentially expressed in response to black spot disease pathogen, M. brunnea f. sp. multigermtubi. Proteins extracted from poplar leaves at 0, 12, 24, 48, and 72 h after pathogen-inoculation were separated by 2-DE. About 500 reproducible protein spots were detected, of which 40 protein spots displayed differential expression in levels and were subjected to Matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) followed by database searching. According to the function, the identified proteins were sorted into five categories, that is, protein synthesis, metabolism, defense response and unclassified proteins.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18222409?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Orendovici-Best, T</style></author><author><style face="normal" font="default" size="100%">Skelly, J M</style></author><author><style face="normal" font="default" size="100%">Davis, D D</style></author><author><style face="normal" font="default" size="100%">Ferdinand, J A</style></author><author><style face="normal" font="default" size="100%">Savage, J E</style></author><author><style face="normal" font="default" size="100%">Stevenson, R E</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Ozone uptake (flux) as it relates to ozone-induced foliar symptoms of Prunus serotina and Populus maximowiziixtrichocarpa.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">151</style></volume><pages><style face="normal" font="default" size="100%">79-92</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Field studies were conducted during 2003 and 2004 from early June to the end of August, at 20 sites of lower or higher elevation within north-central Pennsylvania, using seedlings of black cherry (Prunus serotina, Ehrh.) and ramets of hybrid poplar (Populus maximowiziixtrichocarpa). A linear model was developed to estimate the influence of local environmental conditions on stomatal conductance. The most significant factors explaining stomatal variance were tree species, air temperature, leaf vapor pressure deficit, elevation, and time of day. Overall, environmental factors explained less than 35% of the variation in stomatal conductance. Ozone did not affect gas exchange rates in either poplar or cherry. Ozone-induced foliar injury was positively correlated with cumulative ozone exposures, expressed as SUM40. Overall, the amount of foliar injury was better correlated to a flux-based approach rather than to an exposure-based approach. More severe foliar injuries were observed on plants growing at higher elevations.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17524537?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Pascual, María Belén</style></author><author><style face="normal" font="default" size="100%">Jing, Zhong Ping</style></author><author><style face="normal" font="default" size="100%">Kirby, Edward G</style></author><author><style face="normal" font="default" size="100%">Cánovas, Francisco M</style></author><author><style face="normal" font="default" size="100%">Gallardo, Fernando</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Response of transgenic poplar overexpressing cytosolic glutamine synthetase to phosphinothricin.</style></title><secondary-title><style face="normal" font="default" size="100%">Phytochemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Phytochemistry</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">69</style></volume><pages><style face="normal" font="default" size="100%">382-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Glutamine synthetase (GS) is the main enzyme involved in ammonia assimilation in plants and is the target of phosphinothricin (PPT), an herbicide commonly used for weed control in agriculture. As a result of the inhibition of GS, PPT also blocks photorespiration, resulting in the depletion of leaf amino acid pools leading to the plant death. Hybrid transgenic poplar (Populus tremula x P. alba INRA clone 7171-B4) overexpressing cytosolic GS is characterized by enhanced vegetative growth [Gallardo, F., Fu, J., Cantón, F.R., García-Gutiérrez, A., Cánovas, F.M., Kirby, E.G., 1999. Expression of a conifer glutamine synthetase gene in transgenic poplar. Planta 210, 19-26; Fu, J., Sampalo, R., Gallardo, F., Cánovas, F.M., Kirby, E.G., 2003. Assembly of a cytosolic pine glutamine synthetase holoenzyme in leaves of transgenic poplar leads to enhanced vegetative growth in young plants. Plant Cell Environ. 26, 411-418; Jing, Z.P., Gallardo, F., Pascual, M.B., Sampalo, R., Romero, J., Torres de Navarra, A., Cánovas, F.M., 2004. Improved growth in a field trial of transgenic hybrid poplar overexpressing glutamine synthetase. New Phytol. 164, 137-145], increased photosynthetic and photorespiratory capacities [El-Khatib, R.T., Hamerlynck, E.P., Gallardo, F., Kirby, E.G., 2004. Transgenic poplar characterized by ectopic expression of a pine cytosolic glutamine synthetase gene exhibits enhanced tolerance to water stress. Tree Physiol. 24, 729-736], enhanced tolerance to water stress (El-Khatib et al., 2004), and enhanced nitrogen use efficiency [Man, H.-M., Boriel, R., El-Khatib, R.T., Kirby, E.G., 2005. Characterization of transgenic poplar with ectopic expression of pine cytosolic glutamine synthetase under conditions of varying nitrogen availability. New Phytol. 167, 31-39]. In vitro plantlets of GS transgenic poplar exhibited enhanced resistance to PPT when compared with non-transgenic controls. After 30 days exposure to PPT at an equivalent dose of 275 g ha(-1), growth of GS transgenic poplar plantlets was 5-fold greater than controls. The response of young leaves to PPT treatment depends on physiological state as indicated by GS and Rubisco (LSU) levels. Young leaves from control plants, typically in a low differentiation state, respond to the herbicide showing up-regulation of GS and LSU. In contrast, young leaves from transgenic lines, with higher initial GS and LSU levels compared to control, display up-regulation of NADP(+)-isocitrate dehydrogenase. Differences between control and GS transgenics in their response to PPT are discussed in relation to their differences in photosynthetic and photorespiratory capacities (El-Khatib et al., 2004).</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17888468?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sasaki, Shinya</style></author><author><style face="normal" font="default" size="100%">Nonaka, Daisuke</style></author><author><style face="normal" font="default" size="100%">Wariishi, Hiroyuki</style></author><author><style face="normal" font="default" size="100%">Tsutsumi, Yuji</style></author><author><style face="normal" font="default" size="100%">Kondo, Ryuichiro</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Role of Tyr residues on the protein surface of cationic cell-wall-peroxidase (CWPO-C) from poplar: potential oxidation sites for oxidative polymerization of lignin.</style></title><secondary-title><style face="normal" font="default" size="100%">Phytochemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Phytochemistry</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">69</style></volume><pages><style face="normal" font="default" size="100%">348-55</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">It was previously reported that an unique peroxidase isoenzyme, cationic cell-wall-bound peroxidase (CWPO-C), from poplar callus oxidizes sinapyl alcohol, ferrocytochrome c and synthetic lignin polymers, unlike other plant peroxidases. Here, the catalytic mechanism of CWPO-C was investigated using chemical modification and homology modeling. The simulated CWPO-C structure predicts that the entrance to the heme pocket of CWPO-C is the same size as those of other plant peroxidases, suggesting that ferrocytochrome c and synthetic lignin polymers cannot interact with the heme of CWPO-C. Since Trp and Tyr residues are redox-active, such residues located on the protein surface were predicted to be active sites for CWPO-C. Modification of CWPO-C Trp residues did not suppress its oxidation activities toward guaiacol and syringaldazine. On the other hand, modification of CWPO-C Tyr residues using tetranitromethane strongly suppressed its oxidation activities toward syringaldazine and 2,6-dimethoxyphenol by 90%, respectively, and also suppressed its guaiacol oxidation activity to a lesser extent. Ferrocytochrome c was not oxidized by Tyr-modified CWPO-C. These results indicate that the Tyr residues in CWPO-C mediate its oxidation of syringyl compounds and high-molecular-weight substrates. Homology modeling indicates that Tyr-177 and Tyr-74 are located near the heme and exposed on the protein surface of CWPO-C. These results suggest that Tyr residues on the protein surface are considered to be important for the oxidation activities of CWPO-C with a wide range of substrates, and potentially unique oxidation sites for the plant peroxidase family.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17910963?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Saveyn, An</style></author><author><style face="normal" font="default" size="100%">Steppe, Kathy</style></author><author><style face="normal" font="default" size="100%">McGuire, Mary Anne</style></author><author><style face="normal" font="default" size="100%">Lemeur, Raoul</style></author><author><style face="normal" font="default" size="100%">Teskey, Robert O</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Stem respiration and carbon dioxide efflux of young Populus deltoides trees in relation to temperature and xylem carbon dioxide concentration.</style></title><secondary-title><style face="normal" font="default" size="100%">Oecologia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Oecologia</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">154</style></volume><pages><style face="normal" font="default" size="100%">637-49</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Oxidative respiration is strongly temperature driven. However, in woody stems, efflux of CO(2) to the atmosphere (E (A)), commonly used to estimate the rate of respiration (R (S)), and stem temperature (T (st)) have often been poorly correlated, which we hypothesized was due to transport of respired CO(2) in xylem sap, especially under high rates of sap flow (f (s)). To test this, we measured E (A), T (st), f (s) and xylem sap CO(2) concentrations ([CO(2)*]) in 3-year-old Populus deltoides trees under different weather conditions (sunny and rainy days) in autumn. We also calculated R (S) by mass balance as the sum of both outward and internal CO(2) fluxes and hypothesized that R (S) would correlate better with T (st) than E (A). We found that E (A) sometimes correlated well with T (st), but not on sunny mornings and afternoons or on rainy days. When the temperature effect on E (A) was accounted for, a clear positive relationship between E (A) and xylem [CO(2)*] was found. [CO(2)*] varied diurnally and increased substantially at night and during periods of rain. Changes in [CO(2)*] were related to changes in f (s) but not T (st). We conclude that changes in both respiration and internal CO(2) transport altered E (A). The dominant component flux of R (S) was E (A). However, on a 24-h basis, the internal transport flux represented 9-18% and 3-7% of R (S) on sunny and rainy days, respectively, indicating that the contribution of stem respiration to forest C balance may be larger than previously estimated based on E (A) measurements. Unexpectedly, the relationship between R (S) and T (st) was sometimes weak in two of the three trees. We conclude that in addition to temperature, other factors such as water deficits or substrate availability exert control on the rate of stem respiration so that simple temperature functions are not sufficient to predict stem respiration.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17957386?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Fares, S</style></author><author><style face="normal" font="default" size="100%">Loreto, F</style></author><author><style face="normal" font="default" size="100%">Kleist, E</style></author><author><style face="normal" font="default" size="100%">Wildt, J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Stomatal uptake and stomatal deposition of ozone in isoprene and monoterpene emitting plants.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant biology (Stuttgart, Germany)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Biol (Stuttg)</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">10</style></volume><pages><style face="normal" font="default" size="100%">44-54</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Volatile isoprenoids were reported to protect plants against ozone. To understand whether this could be the result of a direct scavenging of ozone by these molecules, the stomatal and non-stomatal uptake of ozone was estimated in plants emitting isoprene or monoterpenes. Ozone uptake by holm oak (Quercus ilex, a monoterpene emitter) and black poplar (Populus nigra, an isoprene emitter) was studied in whole plant enclosures (continuously stirred tank reactors, CSTR). The ozone uptake by plants was estimated measuring ozone concentration at the inlet and outlet of the reactors, after correcting for the uptake of the enclosure materials. Destruction of ozone at the cuticle or at the plant stems was found to be negligible compared to the ozone uptake through the stomata. For both plant species, a relationship between stomatal conductance and ozone uptake was found. For the poplar, the measured ozone losses were explained by the uptake of ozone through the stomata only, and ozone destruction by gas phase reactions with isoprene was negligible. For the oak, gas phase reactions of ozone with the monoterpenes emitted by the plants contributed significantly to ozone destruction. This was confirmed by two different experiments showing a) that in cases of high stomatal conductance but under low CO(2) concentration, a reduction of monoterpene emission was still associated with reduced O(3) uptake; and b) that ozone losses due to the gas phase reactions only can be measured when using the exhaust from a plant chamber to determine the gas phase reactivity in an empty reaction chamber. Monoterpenes can therefore relevantly scavenge ozone at leaf level contributing to protection against ozone.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17538866?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wang, Jun-Ying</style></author><author><style face="normal" font="default" size="100%">Xia, Xin-Li</style></author><author><style face="normal" font="default" size="100%">Wang, Jun-Ping</style></author><author><style face="normal" font="default" size="100%">Yin, Wei-Lun</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Stress responsive zinc-finger protein gene of Populus euphratica in tobacco enhances salt tolerance.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of integrative plant biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J Integr Plant Biol</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">50</style></volume><pages><style face="normal" font="default" size="100%">56-61</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The Populus euphratica stress responsive zinc-finger protein gene PSTZ, which encodes a protein including typical Cys(2)/His(2) zinc finger structure, was isolated by reverse transcription-polymerase chain reaction from P. euphratica. Northern hybridization revealed that its expression was induced under drought and salt stress conditions. To examine its function, cDNA of the PSTZ gene, driven by the cauliflower mosaic virus 35S promoter, was cloned into a plant expression vector pBin438 and introduced into tobacco plants. Transgenic tobacco showed an enhanced salt tolerance, suggesting that PSTZ may play a role in plant responsiveness to salt stress.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18666952?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Escher, Peter</style></author><author><style face="normal" font="default" size="100%">Peuke, Andreas D</style></author><author><style face="normal" font="default" size="100%">Bannister, Peter</style></author><author><style face="normal" font="default" size="100%">Fink, Siegfried</style></author><author><style face="normal" font="default" size="100%">Hartung, Wolfram</style></author><author><style face="normal" font="default" size="100%">Jiang, Fan</style></author><author><style face="normal" font="default" size="100%">Rennenberg, Heinz</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Transpiration, CO2 assimilation, WUE, and stomatal aperture in leaves of Viscum album (L.): Effect of abscisic acid (ABA) in the xylem sap of its host (Populus x euamericana).</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology and biochemistry : PPB / Société française de physiologie végétale</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol. Biochem.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">46</style></volume><pages><style face="normal" font="default" size="100%">64-70</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Leaves of the mistletoe Viscum album (L.) show a high rate of transpiration, even when the host is under severe drought stress. The hypothesis that a strong control of ABA influx from the xylem sap of the host into the mistletoe prevents stomatal closure in mistletoe leaves was tested under the following conditions: sections of poplar twigs carrying a mistletoe were perfused with artificial xylem sap that contained different ABA concentrations and both transpiration and ABA levels were analysed in mistletoe leaves. Despite variation by a factor of 10(4), the ABA content of the host xylem did not affect ABA levels, leaf transpiration, CO(2) assimilation, WUE, or the degree of stomatal aperture in mistletoe leaves. These observations support the hypothesis of a strong control of ABA influx from the host of the xylem into the mistletoe, although degradation of ABA before it enters the mistletoe leaves cannot be excluded. This mechanism may ensure a water and nutritional status favourable for the mistletoe, even if the water status of the host is impaired. Despite the lack of short-term sensitivity of ABA levels in mistletoe leaves to even strong changes of ABA levels in the xylem sap of the host, ABA levels in mistletoe leaves were relatively high compared to ABA levels in the leaves of several tree species including poplar. Since significant transpiration of the mistletoe leaves was observed despite high ABA levels, a diminished sensitivity of the stomata of mistletoe leaves to ABA has to be concluded. The stomatal density of adaxial Viscum leaves of 89+/-23 stomata per mm is lower than those reported in a study performed at the end of the 19th century.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18042393?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Komárek, Michael</style></author><author><style face="normal" font="default" size="100%">Tlustos, Pavel</style></author><author><style face="normal" font="default" size="100%">Száková, Jirina</style></author><author><style face="normal" font="default" size="100%">Chrastný, Vladislav</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The use of poplar during a two-year induced phytoextraction of metals from contaminated agricultural soils.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">151</style></volume><pages><style face="normal" font="default" size="100%">27-38</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The efficiency of poplar (Populus nigra L.xPopulus maximowiczii Henry.) was assessed during a two-year chemically enhanced phytoextraction of metals from contaminated soils. The tested metal mobilizing agents were EDTA (ethylenediaminetetraacetic acid) and NH4Cl. EDTA was more efficient than chlorides in solubilizing metals (especially Pb) from the soil matrix. The application of chlorides only increased the solubility of Cd and Zn. However, the increased uptake of metals after the application of higher concentrations of mobilizing agents was associated with low biomass yields of the poplar plants and the extraction efficiencies after the two vegetation periods were thus comparable to the untreated plants. Additionally, the application of mobilizing agents led to phytotoxicity effects and increased mobility of metals. Higher phytoextraction efficiencies were observed for Cd and Zn compared to Pb and Cu. Poplars are therefore not suitable for chemically enhanced phytoextraction of metals from severely contaminated agricultural soils.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17467862?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Teuber, M</style></author><author><style face="normal" font="default" size="100%">Zimmer, I</style></author><author><style face="normal" font="default" size="100%">Kreuzwieser, J</style></author><author><style face="normal" font="default" size="100%">Ache, P</style></author><author><style face="normal" font="default" size="100%">Polle, A</style></author><author><style face="normal" font="default" size="100%">Rennenberg, H</style></author><author><style face="normal" font="default" size="100%">Schnitzler, J-P</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">VOC emissions of Grey poplar leaves as affected by salt stress and different N sources.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant biology (Stuttgart, Germany)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Biol (Stuttg)</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">10</style></volume><pages><style face="normal" font="default" size="100%">86-96</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Nitrogen nutrition and salt stress experiments were performed in a greenhouse with hydroponic-cultured, salt-sensitive Grey poplar (Populus x canescens) plants to study the combined influence of different N sources (either 1 mm NO(3) (-) or NH(4)(+)) and salt (up to 75 mm NaCl) on leaf gas exchange, isoprene biosynthesis and VOC emissions. Net assimilation and transpiration proved to be highly sensitive to salt stress and were reduced by approximately 90% at leaf sodium concentrations higher than 1,800 microg Na g dry weight (dw)(-1). In contrast, emissions of isoprene and oxygenated VOC (i.e. acetaldehyde, formaldehyde and acetone) were unaffected. There was no significant effect of combinations of salt stress and N source, and neither NO(3)(-) or NH(4)(+) influenced the salt stress response in the Grey poplar leaves. Also, transcript levels of 1-deoxy-d-xylulose 5-phosphate reductoisomerase (PcDXR) and isoprene synthase (PcISPS) did not respond to the different N sources and only responded slightly to salt application, although isoprene synthase (PcISPS) activity was negatively affected at least in one of two experiments, despite high isoprene emission rates. A significant salt effect was the strong reduction of leaf dimethylallyl diphosphate (DMADP) content, probably due to restricted availability of photosynthates for DMADP biosynthesis. Further consequences of reduced photosynthetic gas exchange and maintaining VOC emissions are a very high C loss, up to 50%, from VOC emissions related to net CO(2) uptake and a strong increase in leaf internal isoprene concentrations, with maximum mean values up to 6.6 microl x l(-1). Why poplar leaves maintain VOC biosynthesis and emission under salt stress conditions, despite impaired photosynthetic CO(2) fixation, is discussed.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18211549?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Dundar, Murat</style></author><author><style face="normal" font="default" size="100%">Nuhoglu, Cigdem</style></author><author><style face="normal" font="default" size="100%">Nuhoglu, Yasar</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Biosorption of Cu(II) ions onto the litter of natural trembling poplar forest.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of hazardous materials</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Hazard. Mater.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Feb 28</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">151</style></volume><pages><style face="normal" font="default" size="100%">86-95</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The litter of natural trembling poplar (Populus tremula) forest (LNTPF) was used for the biosorption of Cu(II) ions in a batch adsorption experiments. The sorption capacity of LNTPF was investigated as a function of pH, particle size, agitating speed, initial Cu(II) concentration, adsorbent concentration and temperature. The efficiency of copper uptake by the used LNTPF increases with a rise of solution pH, adsorbent concentration, agitating speed, temperature, and with a decline of particle size and initial Cu(II) concentration. The biosorption process was very fast; 94% of Cu(II) removal occurred within 5 min and equilibrium was reached at around 30 min. Batch adsorption models, based on the assumption of the pseudo-first order, pseudo-second order mechanism were applied to examine the adsorption kinetics. The pseudo-second order model was found to best fit the kinetic data. EPR studies combined with FTIR spectroscopy were used to represent the biosorption mechanism. Thermodynamic parameters such as DeltaH degrees, DeltaS degrees and DeltaG degrees were calculated. The adsorption process was found to be endothermic and spontaneous. Equilibrium data fitted well to Langmuir adsorption model. This study proved that the LNTPF can be used as an effective, cheap and abundant adsorbent for the treatment of Cu(II) containing wastewaters.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17601663?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Stobrawa, Krzysztof</style></author><author><style face="normal" font="default" size="100%">Lorenc-Plucińska, Gabriela</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Thresholds of heavy-metal toxicity in cuttings of European black poplar (Populus nigra L.) determined according to antioxidant status of fine roots and morphometrical disorders.</style></title><secondary-title><style face="normal" font="default" size="100%">The Science of the total environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Sci. Total Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Feb 1</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">390</style></volume><pages><style face="normal" font="default" size="100%">86-96</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The effects of increasing concentrations of polluted soils collected from two different stands in the direct neighbourhood of a copper smelter were studied by analyzing the activity of lipid peroxidation and antioxidant enzymes in the fine roots of cuttings of black poplar (Populus nigra L.). Morphological parameters of affected and unaffected plants were compared and concentrations of heavy metals in their fine roots were estimated. Copper and lead were the major pollutants, and their threshold concentrations were determined on the basis of positive or negative impact on shoots and root growth, morphological disorders of the roots (thickening, decreasing of fine roots volume), stimulation or inhibition of the most important antioxidant enzymes: catalase (CAT), superoxide dismutase (SOD), guaiacol and ascorbate peroxidases (GPOX, APOX) and glutathione reductase (GR) as well as increasing MDA concentration. Finally, three thresholds of Cu and Pb concentrations resulting in increasing toxicity against plants were proposed, splitting the ranges of the non toxic presence of these metals into soil (Cu&lt;100 ppm, Pb&lt;30 ppm), full tolerance (Cu 100-220 ppm, Pb 30-70 ppm), limited tolerance (Cu 220-650 ppm, Pb 70-200 ppm) and breakdown of tolerance (Cu&gt;650 ppm, Pb&gt;200 ppm).</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17963819?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Riikonen, Johanna</style></author><author><style face="normal" font="default" size="100%">Kets, Katre</style></author><author><style face="normal" font="default" size="100%">Darbah, Joseph</style></author><author><style face="normal" font="default" size="100%">Oksanen, Elina</style></author><author><style face="normal" font="default" size="100%">Sober, Anu</style></author><author><style face="normal" font="default" size="100%">Vapaavuori, Elina</style></author><author><style face="normal" font="default" size="100%">Kubiske, Mark E</style></author><author><style face="normal" font="default" size="100%">Nelson, Neil</style></author><author><style face="normal" font="default" size="100%">Karnosky, David F</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Carbon gain and bud physiology in Populus tremuloides and Betula papyrifera grown under long-term exposure to elevated concentrations of CO2 and O3.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">243-54</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Paper birch (Betula papyrifera Marsh.) and three trembling aspen clones (Populus tremuloides Michx.) were studied to determine if alterations in carbon gain in response to an elevated concentration of CO(2) ([CO(2)]) or O(3) ([O(3)]) or a combination of both affected bud size and carbohydrate composition in autumn, and early leaf development in the following spring. The trees were measured for gas exchange, leaf size, date of leaf abscission, size and biochemical characteristics of the overwintering buds and early leaf development during the 8th-9th year of free-air CO(2) and O(3) exposure at the Aspen FACE site located near Rhinelander, WI. Net photosynthesis was enhanced 49-73% by elevated [CO(2)], and decreased 13-30% by elevated [O(3)]. Elevated [CO(2)] delayed, and elevated [O(3)] tended to accelerate, leaf abscission in autumn. Elevated [CO(2)] increased the ratio of monosaccharides to di- and oligosaccharides in aspen buds, which may indicate a lag in cold acclimation. The total carbon concentration in overwintering buds was unaffected by the treatments, although elevated [O(3)] decreased the amount of starch by 16% in birch buds, and reduced the size of aspen buds, which may be related to the delayed leaf development in aspen during the spring. Elevated [CO(2)] generally ameliorated the effects of elevated [O(3)]. Our results show that both elevated [CO(2)] and elevated [O(3)] have the potential to alter carbon metabolism of overwintering buds. These changes may cause carry-over effects during the next growing season.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18055435?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ulrich, Kristina</style></author><author><style face="normal" font="default" size="100%">Ulrich, Andreas</style></author><author><style face="normal" font="default" size="100%">Ewald, Dietrich</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Diversity of endophytic bacterial communities in poplar grown under field conditions.</style></title><secondary-title><style face="normal" font="default" size="100%">FEMS microbiology ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">FEMS Microbiol. Ecol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">63</style></volume><pages><style face="normal" font="default" size="100%">169-80</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Bacterial endophytes may be important for plant health and other ecologically relevant functions of poplar trees. The composition of endophytic bacteria colonizing the aerial parts of poplar was studied using a multiphasic approach. The terminal restriction fragment length polymorphism analysis of 16S rRNA genes demonstrated the impact of different hybrid poplar clones on the endophytic community structure. Detailed analysis of endophytic bacteria using cultivation methods in combination with cloning of 16S rRNA genes amplified from plant tissue revealed a high phylogenetic diversity of endophytic bacteria with a total of 53 taxa at the genus level that included Proteobacteria, Actinobacteria, Firmicutes and Bacteroidetes. The community structure displayed clear differences in terms of the presence and relative proportions of bacterial taxa between the four poplar clones studied. The results showed that the genetic background of the hybrid poplar clones corresponded well with the endophytic community structure. Out of the 513 isolates and 209 clones identified, Actinobacteria, in particular the family Microbacteriaceae, made up the largest fraction of the isolates, whereas the clone library was dominated by Alpha- and Betaproteobacteria. The most abundant genera among the isolates were Pseudomonas and Curtobacterium, while Sphingomonas prevailed among the clones.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18199082?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bocock, Philip N</style></author><author><style face="normal" font="default" size="100%">Morse, Alison M</style></author><author><style face="normal" font="default" size="100%">Dervinis, Christopher</style></author><author><style face="normal" font="default" size="100%">Davis, John M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Evolution and diversity of invertase genes in Populus trichocarpa.</style></title><secondary-title><style face="normal" font="default" size="100%">Planta</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Planta</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">227</style></volume><pages><style face="normal" font="default" size="100%">565-76</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Invertase (EC 3.2.1.26) plays a key role in carbon utilization as it catalyzes the irreversible hydrolysis of sucrose into glucose and fructose. The invertase family in plants is composed of two sub-families thought to have distinct evolutionary origins and can be distinguished by their pH optima for activity: acid invertases and neutral/alkaline invertases. The acid invertases apparently originated in eubacteria and are targeted to the cell wall and vacuole, while neutral/alkaline invertases apparently originated in cyanobacteria and function in the cytosol. The recently sequenced genome of Populus trichocharpa (Torr. and Gray) allowed us to identify the genes encoding invertase in this woody perennial. Here we describe the identification of eight acid invertase genes; three of which belong to the vacuolar targeted group (PtVIN1-3), and five of which belong to the cell wall targeted group (PtCIN1-5). Similarly, we report the identification of 16 neutral/alkaline invertase genes (PtNIN1-16). Expression analyses using whole genome microarrays and RT-PCR reveal evidence for expression of all invertase family members. An examination of the micro-syntenic regions surrounding the poplar invertase genes reveals extensive colinearity with Arabidopsis invertases. We also find evidence for expression of a novel intronless vacuolar invertase (PtVIN1), which apparently arose from a processed PtVIN2 transcript that re-inserted into the genome. To our knowledge, this is the first intronless invertase found in plants. This work increases the understanding of the role this family plays in carbon allocation and partitioning in forest trees as well as its evolutionary development.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17938954?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bangert, R K</style></author><author><style face="normal" font="default" size="100%">Lonsdorf, E V</style></author><author><style face="normal" font="default" size="100%">Wimp, G M</style></author><author><style face="normal" font="default" size="100%">Shuster, S M</style></author><author><style face="normal" font="default" size="100%">Fischer, D</style></author><author><style face="normal" font="default" size="100%">Schweitzer, J A</style></author><author><style face="normal" font="default" size="100%">Allan, G J</style></author><author><style face="normal" font="default" size="100%">Bailey, J K</style></author><author><style face="normal" font="default" size="100%">Whitham, T G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genetic structure of a foundation species: scaling community phenotypes from the individual to the region.</style></title><secondary-title><style face="normal" font="default" size="100%">Heredity</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Heredity (Edinb)</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">100</style></volume><pages><style face="normal" font="default" size="100%">121-31</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Understanding the local and regional patterns of species distributions has been a major goal of ecological and evolutionary research. The notion that these patterns can be understood through simple quantitative rules is attractive, but while numerous scaling laws exist (e.g., metabolic, fractals), we are aware of no studies that have placed individual traits and community structure together within a genetics based scaling framework. We document the potential for a genetic basis to the scaling of ecological communities, largely based upon our long-term studies of poplars (Populus spp.). The genetic structure and diversity of these foundation species affects riparian ecosystems and determines a much larger community of dependent organisms. Three examples illustrate these ideas. First, there is a strong genetic basis to phytochemistry and tree architecture (both above- and belowground), which can affect diverse organisms and ecosystem processes. Second, empirical studies in the wild show that the local patterns of genetics based community structure scale up to western North America. At multiple spatial scales the arthropod community phenotype is related to the genetic distance among plants that these arthropods depend upon for survival. Third, we suggest that the familiar species-area curve, in which species richness is a function of area, is also a function of genetic diversity. We find that arthropod species richness is closely correlated with the genetic marker diversity and trait variance suggesting a genetic component to these curves. Finally, we discuss how genetic variation can interact with environmental variation to affect community attributes across geographic scales along with conservation implications.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17047690?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Michael, Todd P</style></author><author><style face="normal" font="default" size="100%">Mockler, Todd C</style></author><author><style face="normal" font="default" size="100%">Breton, Ghislain</style></author><author><style face="normal" font="default" size="100%">McEntee, Connor</style></author><author><style face="normal" font="default" size="100%">Byer, Amanda</style></author><author><style face="normal" font="default" size="100%">Trout, Jonathan D</style></author><author><style face="normal" font="default" size="100%">Hazen, Samuel P</style></author><author><style face="normal" font="default" size="100%">Shen, Rongkun</style></author><author><style face="normal" font="default" size="100%">Priest, Henry D</style></author><author><style face="normal" font="default" size="100%">Sullivan, Christopher M</style></author><author><style face="normal" font="default" size="100%">Givan, Scott A</style></author><author><style face="normal" font="default" size="100%">Yanovsky, Marcelo</style></author><author><style face="normal" font="default" size="100%">Hong, Fangxin</style></author><author><style face="normal" font="default" size="100%">Kay, Steve A</style></author><author><style face="normal" font="default" size="100%">Chory, Joanne</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Network discovery pipeline elucidates conserved time-of-day-specific cis-regulatory modules.</style></title><secondary-title><style face="normal" font="default" size="100%">PLoS genetics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">PLoS Genet.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">4</style></volume><pages><style face="normal" font="default" size="100%">e14</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Correct daily phasing of transcription confers an adaptive advantage to almost all organisms, including higher plants. In this study, we describe a hypothesis-driven network discovery pipeline that identifies biologically relevant patterns in genome-scale data. To demonstrate its utility, we analyzed a comprehensive matrix of time courses interrogating the nuclear transcriptome of Arabidopsis thaliana plants grown under different thermocycles, photocycles, and circadian conditions. We show that 89% of Arabidopsis transcripts cycle in at least one condition and that most genes have peak expression at a particular time of day, which shifts depending on the environment. Thermocycles alone can drive at least half of all transcripts critical for synchronizing internal processes such as cell cycle and protein synthesis. We identified at least three distinct transcription modules controlling phase-specific expression, including a new midnight specific module, PBX/TBX/SBX. We validated the network discovery pipeline, as well as the midnight specific module, by demonstrating that the PBX element was sufficient to drive diurnal and circadian condition-dependent expression. Moreover, we show that the three transcription modules are conserved across Arabidopsis, poplar, and rice. These results confirm the complex interplay between thermocycles, photocycles, and the circadian clock on the daily transcription program, and provide a comprehensive view of the conserved genomic targets for a transcriptional network key to successful adaptation.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18248097?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Siedlecka, Anna</style></author><author><style face="normal" font="default" size="100%">Wiklund, Susanne</style></author><author><style face="normal" font="default" size="100%">Péronne, Marie-Amélie</style></author><author><style face="normal" font="default" size="100%">Micheli, Fabienne</style></author><author><style face="normal" font="default" size="100%">Lesniewska, Joanna</style></author><author><style face="normal" font="default" size="100%">Sethson, Ingmar</style></author><author><style face="normal" font="default" size="100%">Edlund, Ulf</style></author><author><style face="normal" font="default" size="100%">Richard, Luc</style></author><author><style face="normal" font="default" size="100%">Sundberg, Björn</style></author><author><style face="normal" font="default" size="100%">Mellerowicz, Ewa J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Pectin methyl esterase inhibits intrusive and symplastic cell growth in developing wood cells of Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">146</style></volume><pages><style face="normal" font="default" size="100%">554-65</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Wood cells, unlike most other cells in plants, grow by a unique combination of intrusive and symplastic growth. Fibers grow in diameter by diffuse symplastic growth, but they elongate solely by intrusive apical growth penetrating the pectin-rich middle lamella that cements neighboring cells together. In contrast, vessel elements grow in diameter by a combination of intrusive and symplastic growth. We demonstrate that an abundant pectin methyl esterase (PME; EC 3.1.1.11) from wood-forming tissues of hybrid aspen (Populus tremula x tremuloides) acts as a negative regulator of both symplastic and intrusive growth of developing wood cells. When PttPME1 expression was up- and down-regulated in transgenic aspen trees, the PME activity in wood-forming tissues was correspondingly altered. PME removes methyl ester groups from homogalacturonan (HG) and transgenic trees had modified HG methylesterification patterns, as demonstrated by two-dimensional nuclear magnetic resonance and immunostaining using PAM1 and LM7 antibodies. In situ distributions of PAM1 and LM7 epitopes revealed changes in pectin methylesterification in transgenic trees that were specifically localized in expanding wood cells. The results show that en block deesterification of HG by PttPME1 inhibits both symplastic growth and intrusive growth. PttPME1 is therefore involved in mechanisms determining fiber width and length in the wood of aspen trees.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18065553?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wiberley, Amy E</style></author><author><style face="normal" font="default" size="100%">Donohue, Autumn R</style></author><author><style face="normal" font="default" size="100%">Meier, Mary E</style></author><author><style face="normal" font="default" size="100%">Westphal, Maiken M</style></author><author><style face="normal" font="default" size="100%">Sharkey, Thomas D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Regulation of isoprene emission in Populus trichocarpa leaves subjected to changing growth temperature.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">31</style></volume><pages><style face="normal" font="default" size="100%">258-67</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The hydrocarbon isoprene is emitted in large quantities from numerous plant species, and has a substantial impact on atmospheric chemistry. Temperature affects isoprene emission at several levels: the temperature at which emission is measured, the temperature at which leaves develop, and the temperatures to which a mature leaf is exposed in the days prior to emission measurement. The molecular regulation of the response to the last of these factors was investigated in this study. When plants were grown at 20 degrees C and moved from 20 to 30 degrees C and back, or grown at 30 degrees C and moved from 30 to 20 degrees C and back, their isoprene emission peaked within 3 h of the move and stabilized over the following 3 d. Trees that developed at 20 degrees C and experienced 30 degrees C episodes had higher isoprene emission capacities than did leaves grown exclusively at 20 degrees C, even 2 weeks after the last 30 degrees C episode. The levels and extractable activities of isoprene synthase protein, which catalyses the synthesis of isoprene, and those of dimethylallyl diphosphate (DMADP), its substrate, alone could not explain observed variations in isoprene emission. Therefore, we conclude that control of isoprene emission in mature leaves is shared between isoprene synthase protein and DMADP supply.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17996012?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hannon, Eugene R</style></author><author><style face="normal" font="default" size="100%">Kittelson, Neal T</style></author><author><style face="normal" font="default" size="100%">Eaton, Jake A</style></author><author><style face="normal" font="default" size="100%">Brown, John J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Screening hybrid poplar clones for susceptibility to Cryptorhynchus lapathi (Coleoptera: Curculionidae).</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of economic entomology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Econ. Entomol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">101</style></volume><pages><style face="normal" font="default" size="100%">199-205</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The poplar-and-willow borer, Cryptorhynchus lapathi (L.) (Coleoptera: Curculionidae), is a wood-boring pest of economic importance in irrigated hybrid poplar (Populus spp.) farms in eastern Washington and Oregon. There is no practical insecticide control tactic against either the larval or adult stage of C. lapathi. To assess variability in C. lapathi toward clone preference, we initiated a no-choice study on 180 caged trees that consisted of five clones in a randomized complete block design. C. lapathi was significantly more successful at establishing a population in two clones with Populus trichocarpa X P. deltoides (TxD) parentage (female x male) than in either of two clones with P. deltoides x P. nigra (DxN) parentage (female x male), or a single clone with P. deltoides x P. maximowiczii (DxM) parentage (female X male). There were no significant differences in the rate of weevil development among infested clones, with the exception of DxM trees. Larvae in DxM clones developed on average to the fourth size grouping and those in the two TxD clones developed on average to the fifth size grouping, and this difference was significant. These results corroborate our general damage surveys conducted in the field. Our findings provide growers with the option to choose less susceptible varieties when replanting.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18330136?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhao, Nan</style></author><author><style face="normal" font="default" size="100%">Ferrer, Jean-Luc</style></author><author><style face="normal" font="default" size="100%">Ross, Jeannine</style></author><author><style face="normal" font="default" size="100%">Guan, Ju</style></author><author><style face="normal" font="default" size="100%">Yang, Yue</style></author><author><style face="normal" font="default" size="100%">Pichersky, Eran</style></author><author><style face="normal" font="default" size="100%">Noel, Joseph P</style></author><author><style face="normal" font="default" size="100%">Chen, Feng</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Structural, biochemical, and phylogenetic analyses suggest that indole-3-acetic acid methyltransferase is an evolutionarily ancient member of the SABATH family.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">146</style></volume><pages><style face="normal" font="default" size="100%">455-67</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The plant SABATH protein family encompasses a group of related small-molecule methyltransferases (MTs) that catalyze the S-adenosyl-L-methionine-dependent methylation of natural chemicals encompassing widely divergent structures. Indole-3-acetic acid (IAA) methyltransferase (IAMT) is a member of the SABATH family that modulates IAA homeostasis in plant tissues through methylation of IAA's free carboxyl group. The crystal structure of Arabidopsis (Arabidopsis thaliana) IAMT (AtIAMT1) was determined and refined to 2.75 A resolution. The overall tertiary and quaternary structures closely resemble the two-domain bilobed monomer and the dimeric arrangement, respectively, previously observed for the related salicylic acid carboxyl methyltransferase from Clarkia breweri (CbSAMT). To further our understanding of the biological function and evolution of SABATHs, especially of IAMT, we analyzed the SABATH gene family in the rice (Oryza sativa) genome. Forty-one OsSABATH genes were identified. Expression analysis showed that more than one-half of the OsSABATH genes were transcribed in one or multiple organs. The OsSABATH gene most similar to AtIAMT1 is OsSABATH4. Escherichia coli-expressed OsSABATH4 protein displayed the highest level of catalytic activity toward IAA and was therefore named OsIAMT1. OsIAMT1 exhibited kinetic properties similar to AtIAMT1 and poplar IAMT (PtIAMT1). Structural modeling of OsIAMT1 and PtIAMT1 using the experimentally determined structure of AtIAMT1 reported here as a template revealed conserved structural features of IAMTs within the active-site cavity that are divergent from functionally distinct members of the SABATH family, such as CbSAMT. Phylogenetic analysis revealed that IAMTs from Arabidopsis, rice, and poplar (Populus spp.) form a monophyletic group. Thus, structural, biochemical, and phylogenetic evidence supports the hypothesis that IAMT is an evolutionarily ancient member of the SABATH family likely to play a critical role in IAA homeostasis across a wide range of plants.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18162595?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wang, Ji</style></author><author><style face="normal" font="default" size="100%">Zhu, Mu Lan</style></author><author><style face="normal" font="default" size="100%">Wei, Zhi Ming</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Cotton laccase gene overexpression in transgenic Populus alba var. pyramidalis and its effects on the lignin biosynthesis in transgenic plants].</style></title><secondary-title><style face="normal" font="default" size="100%">Fen zi xi bao sheng wu xue bao = Journal of molecular cell biology / Zhongguo xi bao sheng wu xue xue hui zhu ban</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Fen Zi Xi Bao Sheng Wu Xue Bao</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">41</style></volume><pages><style face="normal" font="default" size="100%">11-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Using petioles as explants, a cotton laccase cDNA (GaLA C1) was introduced into Populus alba var. pyramidalis by A. tumefaciens-mediated transformation. PCR and Southern blot analysis indicated that transgene was stably integrated into the genome of transformants. Enzyme assay showed that laccase activity was obviously increased in transformants. As compared with untransformed control, total lignin content in all tested transgenic lines was elevated in varying degrees (as highest as 21.5%). Histochemical staining of lignin further confirmed that overexpressing GaLA C1 could result in increased lignin content in transformants. Together, our data strongly suggested that GaLA C1 may participate in lignin synthesis and this is the first direct transgenic evidence for the involvement of plant laccases in lignification.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18464585?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Nieminen, Kaisa</style></author><author><style face="normal" font="default" size="100%">Immanen, Juha</style></author><author><style face="normal" font="default" size="100%">Laxell, Marjukka</style></author><author><style face="normal" font="default" size="100%">Kauppinen, Leila</style></author><author><style face="normal" font="default" size="100%">Tarkowski, Petr</style></author><author><style face="normal" font="default" size="100%">Dolezal, Karel</style></author><author><style face="normal" font="default" size="100%">Tähtiharju, Sari</style></author><author><style face="normal" font="default" size="100%">Elo, Annakaisa</style></author><author><style face="normal" font="default" size="100%">Decourteix, Mélanie</style></author><author><style face="normal" font="default" size="100%">Ljung, Karin</style></author><author><style face="normal" font="default" size="100%">Bhalerao, Rishikesh</style></author><author><style face="normal" font="default" size="100%">Keinonen, Kaija</style></author><author><style face="normal" font="default" size="100%">Albert, Victor A</style></author><author><style face="normal" font="default" size="100%">Helariutta, Ykä</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Cytokinin signaling regulates cambial development in poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Proceedings of the National Academy of Sciences of the United States of America</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Proc. Natl. Acad. Sci. U.S.A.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Dec 16</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">105</style></volume><pages><style face="normal" font="default" size="100%">20032-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Although a substantial proportion of plant biomass originates from the activity of vascular cambium, the molecular basis of radial plant growth is still largely unknown. To address whether cytokinins are required for cambial activity, we studied cytokinin signaling across the cambial zones of 2 tree species, poplar (Populus trichocarpa) and birch (Betula pendula). We observed an expression peak for genes encoding cytokinin receptors in the dividing cambial cells. We reduced cytokinin levels endogenously by engineering transgenic poplar trees (P. tremula x tremuloides) to express a cytokinin catabolic gene, Arabidopsis CYTOKININ OXIDASE 2, under the promoter of a birch CYTOKININ RECEPTOR 1 gene. Transgenic trees showed reduced concentration of a biologically active cytokinin, correlating with impaired cytokinin responsiveness. In these trees, both apical and radial growth was compromised. However, radial growth was more affected, as illustrated by a thinner stem diameter than in WT at same height. To dissect radial from apical growth inhibition, we performed a reciprocal grafting experiment. WT scion outgrew the diameter of transgenic stock, implicating cytokinin activity as a direct determinant of radial growth. The reduced radial growth correlated with a reduced number of cambial cell layers. Moreover, expression of a cytokinin primary response gene was dramatically reduced in the thin-stemmed transgenic trees. Thus, a reduced level of cytokinin signaling is the primary basis for the impaired cambial growth observed. Together, our results show that cytokinins are major hormonal regulators required for cambial development.</style></abstract><issue><style face="normal" font="default" size="100%">50</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19064928?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hansen, Frederik T</style></author><author><style face="normal" font="default" size="100%">Madsen, Claus K</style></author><author><style face="normal" font="default" size="100%">Nordland, Anne Mette</style></author><author><style face="normal" font="default" size="100%">Grasser, Marion</style></author><author><style face="normal" font="default" size="100%">Merkle, Thomas</style></author><author><style face="normal" font="default" size="100%">Grasser, Klaus D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A novel family of plant DNA-binding proteins containing both HMG-box and AT-rich interaction domains.</style></title><secondary-title><style face="normal" font="default" size="100%">Biochemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biochemistry</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Dec 16</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">47</style></volume><pages><style face="normal" font="default" size="100%">13207-14</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The A/T-rich interaction domain (ARID) and the HMG-box domain represent DNA-interaction modules that are found in sequence-specific as well as nonsequence-specific DNA-binding proteins. Both domains are found in a variety of DNA-interacting proteins in a wide range of eukaryotic organisms. Proteins that contain both an ARID and an HMG-box domain, here termed ARID-HMG proteins, appear to be specific for plants. This protein family is conserved in higher plants (both mono- and dicot plants) as well as lower plants such as the moss Physcomitrella. Since ARID-HMG proteins have not been studied experimentally, we have examined here two family members from Arabidopsis. The genes encoding ARID-HMG1 and ARID-HMG2 are widely expressed in Arabidopsis but at different levels. Subcellular localization experiments studying ARID-HMG1 and ARID-HMG2 fused to GFP by fluorescence microscopy show that both proteins localize primarily to cell nuclei. Analyses of the DNA-binding properties using electrophoretic mobility shift assays revealed that mediated by the HMG-box domain, ARID-HMG1 binds structure specifically to DNA minicircles. Mediated by the ARID, the protein binds preferentially to A/T-rich DNA, when compared with G/C-rich DNA. Therefore, both DNA-binding domains contribute to the DNA interactions of ARID-HMG1. Accordingly, the protein combines DNA-binding properties characteristic of ARID and HMG-box proteins.</style></abstract><issue><style face="normal" font="default" size="100%">50</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19053246?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhang, Bo</style></author><author><style face="normal" font="default" size="100%">von Keitz, Marc</style></author><author><style face="normal" font="default" size="100%">Valentas, Kenneth</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Maximizing the liquid fuel yield in a biorefining process.</style></title><secondary-title><style face="normal" font="default" size="100%">Biotechnology and bioengineering</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biotechnol. Bioeng.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Dec 1</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">101</style></volume><pages><style face="normal" font="default" size="100%">903-12</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Biorefining strives to recover the maximum value from each fraction, at minimum energy cost. In order to seek an unbiased and thorough assessment of the alleged opportunity offered by biomass fuels, the direct conversion of various lignocellulosic biomass was studied: aspen pulp wood (Populus tremuloides), aspen wood pretreated with dilute acid, aspen lignin, aspen logging residues, corn stalk, corn spathe, corn cob, corn stover, corn stover pellet, corn stover pretreated with dilute acid, and lignin extracted from corn stover. Besides the heating rate, the yield of liquid products was found to be dependent on the final liquefaction temperature and the length of liquefaction time. The major compounds of the liquid products from various origins were identified by GC-MS. The lignin was found to be a good candidate for the liquefaction process, and biomass fractionation was necessary to maximize the yield of the liquid bio-fuel. The results suggest a biorefinery process accompanying pretreatment, fermentation to ethanol, liquefaction to bio-crude oil, and other thermo-conversion technologies, such as gasification. Other biorefinery options, including supercritical water gasification and the effectual utilization of the bio-crude oil, are also addressed.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18781691?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wertin, Timothy M</style></author><author><style face="normal" font="default" size="100%">Teskey, Robert O</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Close coupling of whole-plant respiration to net photosynthesis and carbohydrates.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">1831-40</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We studied the effect of changes in net photosynthesis (A(net)) on respiration, soluble sugars and carbohydrates in Populus deltoides Bartr. ex Marsh. saplings under controlled environmental conditions by making daily measurements of leaf respiration (R(d)), stem CO(2) efflux and root CO(2) efflux at a constant temperature in growth chambers. After a pretreatment period, one of three treatments was applied for 5 to 7 days: (1) increased atmospheric CO(2) concentration; (2) decreased photoperiod and photosynthetic photon flux (PPF); or (3) continuous darkness. Increased A(net) in response to elevated CO(2) concentration resulted in a sustained increase in whole-plant respiration, with R(d) increasing 46%, stem CO(2) efflux increasing 130% and root CO(2) efflux increasing 16%. Elevated CO(2) concentration also caused a significant increase in leaf soluble sugars. Decreasing photoperiod and PPF or complete darkness caused a rapid decrease in respiration throughout the saplings. In the low light treatment, R(d) decreased 40%, stem CO(2) efflux decreased 78%, root CO(2) efflux decreased 74% and significant decreases in leaf and root soluble sugar and leaf nonstructural carbohydrate concentrations were observed. Continuous darkness resulted in a 70% decrease in R(d), a 65% decrease in stem CO(2) efflux, a 73% decrease in root CO(2) efflux and significant decreases in leaf and root soluble sugar and root carbohydrate concentrations. In all treatments, changes in respiration rates in all tissues occurred within hours of treatment application. In addition, a diurnal pattern in root CO(2) efflux was observed throughout the experiment under constant environmental conditions. The observed rapid changes in whole-plant respiration following treatment application and the diurnal patterns in root CO(2) efflux suggest that growth and maintenance respiration in the saplings was strongly dependent on newly acquired carbohydrates.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19193566?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gou, Jin-Ying</style></author><author><style face="normal" font="default" size="100%">Park, Simone</style></author><author><style face="normal" font="default" size="100%">Yu, Xiao-Hong</style></author><author><style face="normal" font="default" size="100%">Miller, Lisa M</style></author><author><style face="normal" font="default" size="100%">Liu, Chang-Jun</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Compositional characterization and imaging of &quot;wall-bound&quot; acylesters of Populus trichocarpa reveal differential accumulation of acyl molecules in normal and reactive woods.</style></title><secondary-title><style face="normal" font="default" size="100%">Planta</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Planta</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">229</style></volume><pages><style face="normal" font="default" size="100%">15-24</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Acylesterification is one of the common modifications of cell wall non-cellulosic polysaccharides and/or lignin primarily in monocot plants. We analyzed the cell-wall acylesters of black cottonwood (Populus trichocarpa Torr. &amp; Gray) with liquid chromatography-mass spectrometry (LC-MS), Fourier transform-infrared (FT-IR) microspectroscopy, and synchrotron infrared (IR) imaging facility. The results revealed that the cell wall of dicotyledonous poplar, as the walls of many monocot grasses, contains a considerable amount of acylesters, primarily acetyl and p-hydroxycinnamoyl molecules. The &quot;wall-bound&quot; acetate and phenolics display a distinct tissue specific-, bending stress responsible- and developmental-accumulation pattern. The &quot;wall-bound&quot; p-coumarate predominantly accumulated in young leaves and decreased in mature leaves, whereas acetate and ferulate mostly amassed in the cell wall of stems. Along the development of stem, the level of the &quot;wall-bound&quot; ferulate gradually increased, while the basal level of p-coumarate further decreased. Induction of tension wood decreased the accumulation of the &quot;wall-bound&quot; phenolics while the level of acetate remained constant. Synchrotron IR-mediated chemical compositional imaging revealed a close spatial distribution of acylesters with cell wall polysaccharides in poplar stem. These results indicate that different &quot;wall-bound&quot; acylesters play distinct roles in poplar cell wall structural construction and/or metabolism of cell wall matrix components.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18820945?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Di Baccio, Daniela</style></author><author><style face="normal" font="default" size="100%">Castagna, Antonella</style></author><author><style face="normal" font="default" size="100%">Paoletti, Elena</style></author><author><style face="normal" font="default" size="100%">Sebastiani, Luca</style></author><author><style face="normal" font="default" size="100%">Ranieri, Annamaria</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Could the differences in O(3) sensitivity between two poplar clones be related to a difference in antioxidant defense and secondary metabolic response to O(3) influx?</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">1761-72</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Increasing global background concentrations of tropospheric ozone (O(3)) are expected to affect both crops and forest ecosystems negatively. The phytotoxic effects of O(3) are mainly associated with the O(3)-induced production of reactive oxygen species (ROS) in excess of the ability of the plant to maintain ROS below the tolerance threshold. It is the balance between O(3) uptake and cellular antioxidant potential that determines O(3) effects on vegetation. The greater sensitivity to ambient O(3) exposure (60 nl l(-1) O(3), 15 days, 5 h a day) of poplar clone Eridano (Populus deltoides x maximowiczii) compared with clone I-214 (P. x euramericana) was reflected in a lower photosynthetic efficiency, higher stomatal conductance and hydrogen peroxide (H(2)O(2)) accumulation and more pronounced leaf tissue membrane injury in Eridano than in I-214. We checked if the differences in clonal responses to O(3) fumigation were related to differing capacities for antioxidant defense and phenylpropanoid metabolism and found that the increases in foliar ascorbate and phenolic concentrations and phenylpropanoid metabolism in Eridano were insufficient to counteract H(2)O(2) accumulation and the consequent oxidative stress. This was probably because the higher influx of O(3) into Eridano leaves compared with I-214 leaves resulted in a lower potential detoxification capacity per unit of O(3) influx.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19193559?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">González, Grizelle</style></author><author><style face="normal" font="default" size="100%">Gould, William A</style></author><author><style face="normal" font="default" size="100%">Hudak, Andrew T</style></author><author><style face="normal" font="default" size="100%">Hollingsworth, Teresa Nettleton</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Decay of aspen (Populus tremuloides Michx.) wood in moist and dry boreal, temperate, and tropical forest fragments.</style></title><secondary-title><style face="normal" font="default" size="100%">Ambio</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ambio</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">37</style></volume><pages><style face="normal" font="default" size="100%">588-97</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In this study, we set up a wood decomposition experiment to i) quantify the percent of mass remaining, decay constant and performance strength of aspen stakes (Populus tremuloides) in dry and moist boreal (Alaska and Minnesota, USA), temperate (Washington and Idaho, USA), and tropical (Puerto Rico) forest types, and ii) determine the effects of fragmentation on wood decomposition rates as related to fragment size, forest age (and/or structure) and climate at the macro- and meso-scales. Fragment sizes represented the landscape variability within a climatic region. Overall, the mean small fragments area ranged from 10-14 ha, medium-sized fragments 33 to 60 ha, and large fragments 100-240 ha. We found that: i) aspen stakes decayed fastest in the tropical sites, and the slowest in the temperate forest fragments, ii) the percent of mass remaining was significantly greater in dry than in moist forests in boreal and temperate fragments, while the opposite was true for the tropical forest fragments, iii) no effect of fragment size on the percent of mass remaining of aspen stakes in the boreal sites, temperate dry, and tropical moist forests, and iv) no significant differences of aspen wood decay between forest edges and interior forest in boreal, temperate and tropical fragments. We conclude that: i) moisture condition is an important control over wood decomposition over broad climate gradients; and that such relationship can be non linear, and ii) the presence of a particular group of organism (termites) can significantly alter the decay rates of wood more than what might be predicted based on climatic factors alone. Biotic controls on wood decay might be more important predictors of wood decay in tropical regions, while abiotic constraints seems to be important determinants of decay in cold forested fragments.</style></abstract><issue><style face="normal" font="default" size="100%">7-8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19205182?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Huynh, T T</style></author><author><style face="normal" font="default" size="100%">Laidlaw, W S</style></author><author><style face="normal" font="default" size="100%">Singh, B</style></author><author><style face="normal" font="default" size="100%">Gregory, D</style></author><author><style face="normal" font="default" size="100%">Baker, A J M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Effects of phytoextraction on heavy metal concentrations and pH of pore-water of biosolids determined using an in situ sampling technique.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">156</style></volume><pages><style face="normal" font="default" size="100%">874-82</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Heavy metal concentrations and pH of pore-water in contaminated substrates are important factors in controlling metal uptake by plants. We investigated the effects of phytoextraction on these properties in the solution phase of biosolids and diluted biosolids in a 12-month phytoextraction column experiment. Phytoextraction using Salix and Populus spp. temporarily decreased pore-water pH of the substrates over the experimental period followed by a return to initial pH conditions. Salixxreichardtii and Populus balsamifera effectively extracted Ni, Zn and Cd and actively mobilized these metals from the solid to the solution phase. S.xreichardtii had the stronger effect on mobilization of metals due to its larger root system. Phytoextraction did not affect Cu in the solution phase of the biosolids. Heavy metals were leached down to lower depths of the columns during the phytoextraction process.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18586368?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lyons, Eric</style></author><author><style face="normal" font="default" size="100%">Pedersen, Brent</style></author><author><style face="normal" font="default" size="100%">Kane, Josh</style></author><author><style face="normal" font="default" size="100%">Alam, Maqsudul</style></author><author><style face="normal" font="default" size="100%">Ming, Ray</style></author><author><style face="normal" font="default" size="100%">Tang, Haibao</style></author><author><style face="normal" font="default" size="100%">Wang, Xiyin</style></author><author><style face="normal" font="default" size="100%">Bowers, John</style></author><author><style face="normal" font="default" size="100%">Paterson, Andrew</style></author><author><style face="normal" font="default" size="100%">Lisch, Damon</style></author><author><style face="normal" font="default" size="100%">Freeling, Michael</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Finding and comparing syntenic regions among Arabidopsis and the outgroups papaya, poplar, and grape: CoGe with rosids.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">148</style></volume><pages><style face="normal" font="default" size="100%">1772-81</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In addition to the genomes of Arabidopsis (Arabidopsis thaliana) and poplar (Populus trichocarpa), two near-complete rosid genome sequences, grape (Vitis vinifera) and papaya (Carica papaya), have been recently released. The phylogenetic relationship among these four genomes and the placement of their three independent, fractionated tetraploidies sum to a powerful comparative genomic system. CoGe, a platform of multiple whole or near-complete genome sequences, provides an integrative Web-based system to find and align syntenic chromosomal regions and visualize the output in an intuitive and interactive manner. CoGe has been customized to specifically support comparisons among the rosids. Crucial facts and definitions are presented to clearly describe the sorts of biological questions that might be answered in part using CoGe, including patterns of DNA conservation, accuracy of annotation, transposability of individual genes, subfunctionalization and/or fractionation of syntenic gene sets, and conserved noncoding sequence content. This précis of an online tutorial, CoGe with Rosids (http://tinyurl.com/4a23pk), presents sample results graphically.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18952863?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Velikova, Violeta</style></author><author><style face="normal" font="default" size="100%">Fares, Silvano</style></author><author><style face="normal" font="default" size="100%">Loreto, Francesco</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Isoprene and nitric oxide reduce damages in leaves exposed to oxidative stress.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">31</style></volume><pages><style face="normal" font="default" size="100%">1882-94</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Isoprene and nitric oxide (NO) are two volatile molecules that are produced in leaves. Both compounds were suggested to have an important protective role against stresses. We tested, in two isoprene-emitting species, Populus nigra and Phragmites australis, whether: (1) NO emission outside leaves is measurable and is affected by oxidative stresses; and (2) isoprene and NO protect leaves against oxidative stresses, both singularly and in combination. The emission of NO was undetectable, and the compensation point was very low in control poplar leaves. Both emission and compensation point increased dramatically in stressed leaves. NO emission was inversely associated with stomatal conductance. More NO was emitted in leaves that were isoprene-inhibited, and more isoprene was emitted when NO was reduced by NO scavenger c-PTIO. Both isoprene and NO reduced oxidative damages. Isoprene-emitting leaves which were also fumigated with NO, or treated with NO donor, showed low damage to photosynthesis, a reduced accumulation of H(2)O(2) and a reduced membrane denaturation. We conclude that measurable amounts of NO are only produced and emitted by stressed leaves, that both isoprene and NO are effective antioxidant molecules and that an additional protection is achieved when both molecules are released.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18811730?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Li, Jingyi</style></author><author><style face="normal" font="default" size="100%">Brunner, Amy M</style></author><author><style face="normal" font="default" size="100%">Meilan, Richard</style></author><author><style face="normal" font="default" size="100%">Strauss, Steven H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Matrix attachment region elements have small and variable effects on transgene expression and stability in field-grown Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant biotechnology journal</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Biotechnol. J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">6</style></volume><pages><style face="normal" font="default" size="100%">887-96</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Matrix attachment regions (MARs) are thought to buffer transgenes from the influence of surrounding chromosomal sequences, and therefore to reduce transgene silencing and variation in expression. The statistical properties of more than 400 independent transgenic events produced in Populus, with and without flanking MAR elements from the tobacco root gene RB7, were analysed. The expression of two reporter genes in two poplar clones during three phases of vegetative growth, and the association of T-DNA characteristics with expression, was examined. It was found that MARs did not show a consistent effect on transgene expression levels; they had no effect on the green fluorescent protein (GFP) reporter gene, but reduced expression in the Basta resistance (BAR) reporter gene by 23%. The presence of MARs reduced expression variability within transformant populations, apparently by reducing the number of silenced or weakly expressing events. Transgene expression was highly stable over vegetative growth cycles that spanned 3 years of growth in the glasshouse and field, but MARs showed no association with the strength of correlations in expression over the years. Nonetheless, MARs increased the correlation in expression between a p35S::GFP and prbcS::BAR transgene linked on the same vector, but the effect was small and varied between the years. The presence of MARs had no effect on the transgene copy number, but was positively associated with T-DNA truncations, as well as with the formation of direct over inverted repeats at the same chromosomal locus.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19548343?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Nonis, Alberto</style></author><author><style face="normal" font="default" size="100%">Ruperti, Benedetto</style></author><author><style face="normal" font="default" size="100%">Pierasco, Alessandro</style></author><author><style face="normal" font="default" size="100%">Canaguier, Aurelie</style></author><author><style face="normal" font="default" size="100%">Adam-Blondon, Anne-Françoise</style></author><author><style face="normal" font="default" size="100%">Di Gaspero, Gabriele</style></author><author><style face="normal" font="default" size="100%">Vizzotto, Giannina</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Neutral invertases in grapevine and comparative analysis with Arabidopsis, poplar and rice.</style></title><secondary-title><style face="normal" font="default" size="100%">Planta</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Planta</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">229</style></volume><pages><style face="normal" font="default" size="100%">129-42</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Neutral invertases (NIs, EC 3.2.1.26) cleave sucrose to glucose and fructose. They are encoded by a small gene family of 9 members in the Arabidopsis genome, 8 in rice, 16 in poplar and 9 in Vitis vinifera (L.). The grapevine NIs were identified in the 8.4X genome assembly of the quasi-homozygous line PN40024. In addition, alleles of three NIs were sequenced in the heterozygous cultivar 'Cabernet Sauvignon'. Analyses of sequence variation between alleles, homoeologous and paralogous copies in grapevine and their orthologues in Arabidopsis, poplar and rice are provided. In grapevine, NIs were classified into four alpha NIs and five beta NIs and subsequently grouped into hierarchical clades using a combination of evidence including amino acid identity, exon/intron structure, rate of synonymous substitutions (K (s)) and chromosomal distribution. Estimation of K (s) proved the ancient origin of all NIs and the lack of expansion by gene duplication past the event of polyploidisation. We then focused on transcription analysis of five NIs for which evidence of expression was available from expressed sequence tag databases. Among these, four NIs consisted of pairs of homoeologous copies, each pair lying on a pair of chromosomes duplicated by polyploidy. Unequal expression of homoeologous genes was observed by quantitative RT-PCR in leaf, flower, seed and root tissues. Since NIs might play significant roles in fruit and wine quality, NIs expression was monitored in flesh and skin of 'Merlot' berries and shown in parallel with the suite of changes that accompany fruit ripening, including glucose and fructose accumulation.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18800225?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Brundu, Giuseppe</style></author><author><style face="normal" font="default" size="100%">Lupi, Renato</style></author><author><style face="normal" font="default" size="100%">Zapelli, Ilaria</style></author><author><style face="normal" font="default" size="100%">Fossati, Tiziana</style></author><author><style face="normal" font="default" size="100%">Patrignani, Giuseppe</style></author><author><style face="normal" font="default" size="100%">Camarda, Ignazio</style></author><author><style face="normal" font="default" size="100%">Sala, Francesco</style></author><author><style face="normal" font="default" size="100%">Castiglione, Stefano</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The origin of clonal diversity and structure of Populus alba in Sardinia: evidence from nuclear and plastid microsatellite markers.</style></title><secondary-title><style face="normal" font="default" size="100%">Annals of botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ann. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">102</style></volume><pages><style face="normal" font="default" size="100%">997-1006</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Populus alba is a thermophilic forest tree present in the Mediterranean basin. Its habitat is highly fragmented and its distribution range has been subject to long-term human interference, resulting in debate surrounding whether certain populations are native or exotic in origin. In particular, populations from the islands of Corsica and Sardinia are of uncertain origin. While populations of P. alba mainly reproduce sexually, clonal reproduction is also common. The aims of this study were to locate and molecularly characterize the poorly studied island populations of P. alba and compare these with samples from various spatial scales, in order to provide information on the genetic structure and phylogeography of this species. This information will provide evidence on whether the species is native to Sardinia, which is important for the development of conservation strategies.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18845663?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bagard, Matthieu</style></author><author><style face="normal" font="default" size="100%">Le Thiec, Didier</style></author><author><style face="normal" font="default" size="100%">Delacote, Emilien</style></author><author><style face="normal" font="default" size="100%">Hasenfratz-Sauder, Marie-Paule</style></author><author><style face="normal" font="default" size="100%">Banvoy, Jacques</style></author><author><style face="normal" font="default" size="100%">Gérard, Joëlle</style></author><author><style face="normal" font="default" size="100%">Dizengremel, Pierre</style></author><author><style face="normal" font="default" size="100%">Jolivet, Yves</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Ozone-induced changes in photosynthesis and photorespiration of hybrid poplar in relation to the developmental stage of the leaves.</style></title><secondary-title><style face="normal" font="default" size="100%">Physiologia plantarum</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Physiol Plant</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">134</style></volume><pages><style face="normal" font="default" size="100%">559-74</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Young poplar trees (Populus tremula Michx. x Populus alba L. clone INRA 717-1B4) were subjected to 120 ppb of ozone for 35 days in phytotronic chambers. Treated trees displayed precocious leaf senescence and visible symptoms of injury (dark brown/black upper surface stippling) exclusively observed on fully expanded leaves. In these leaves, ozone reduced parameters related to photochemistry (Chl content and maximum rate of photosynthetic electron transport) and photosynthetic CO(2) fixation [net CO(2) assimilation, Rubisco (ribulose-1,5-bisphosphate carboxylase oxygenase) activity and maximum velocity of Rubisco for carboxylation]. In fully expanded leaves, the rate of photorespiration as estimated from Chl fluorescence was markedly impaired by the ozone treatment together with the activity of photorespiratory enzymes (Rubisco and glycolate oxidase). Immunoblot analysis revealed a decrease in the content of serine hydroxymethyltransferase in treated mature leaves, while the content of the H subunit of the glycine decarboxylase complex was not modified. Leaves in the early period of expansion were exempt from visible symptoms of injury and remained unaffected as regards all measured parameters. Leaves reaching full expansion under ozone exposure showed potential responses of protection (stimulation of mitochondrial respiration and transitory stomatal closure). Our data underline the major role of leaf phenology in ozone sensitivity of photosynthetic processes and reveal a marked ozone-induced inhibition of photorespiration.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18823329?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Begum, Shahanara</style></author><author><style face="normal" font="default" size="100%">Nakaba, Satoshi</style></author><author><style face="normal" font="default" size="100%">Bayramzadeh, Vilma</style></author><author><style face="normal" font="default" size="100%">Oribe, Yuichiro</style></author><author><style face="normal" font="default" size="100%">Kubo, Takafumi</style></author><author><style face="normal" font="default" size="100%">Funada, Ryo</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Temperature responses of cambial reactivation and xylem differentiation in hybrid poplar (Populus sieboldii x P. grandidentata) under natural conditions.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">1813-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Several studies have demonstrated that localized heating of tree stems induces localized cambial reactivation. We analyzed by light microscopy the effects of early spring increases in ambient temperature in 2005 and 2007 on the timing of cambial reactivation and xylem differentiation in stems of two trees of a cloned deciduous hardwood hybrid poplar (Populus sieboldii Miquel. x P. grandidentata Michx.) growing under natural conditions. Meteorological data at the study site showed that temperatures in late winter and early spring differed markedly between 2005 and 2007, with trends toward higher temperatures starting around April 3 in 2005 and around March 20 in 2007. Cambial reactivation occurred about 17 days earlier in 2007 than in 2005. The cumulative daily maximum temperature in excess of 15 degrees C (maximum daily temperatures minus 15 degrees C) in late winter and early spring before cambial reactivation was defined as the cambial reactivation index (CRI(15)). Cambial reactivation, which began when the minimum temperature rose above 0 degrees C, occurred when the CRI(15) was 93 and 96 degrees C in 2005 and 2007, respectively. The differentiation of secondary xylem started earlier in 2007 than in 2005. On May 27, we found a wider current-year band of xylem and a higher frequency of small-diameter vessel elements in 2007 than in 2005. We propose that the timing of cambial reactivation is controlled by air temperature and that earlier cambial reactivation induces earlier differentiation of xylem in hybrid poplar under natural conditions. Our results indicate that the CRI might be a useful indicator of the timing of cambial reactivation.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19193564?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Evans, Luke M</style></author><author><style face="normal" font="default" size="100%">Allan, Gerard J</style></author><author><style face="normal" font="default" size="100%">Shuster, Stephen M</style></author><author><style face="normal" font="default" size="100%">Woolbright, Scott A</style></author><author><style face="normal" font="default" size="100%">Whitham, Thomas G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Tree hybridization and genotypic variation drive cryptic speciation of a specialist mite herbivore.</style></title><secondary-title><style face="normal" font="default" size="100%">Evolution; international journal of organic evolution</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Evolution</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">62</style></volume><pages><style face="normal" font="default" size="100%">3027-40</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Few studies have investigated the roles that plant hybridization and individual plant genotype play in promoting population divergence within arthropod species. Using nrDNA sequence information and reciprocal transfer experiments, we examined how tree cross type (i.e., pure Populus angustifolia and P. angustifolia x P. fremontii F(1) type hybrids) and individual tree genotype influence host race formation in the bud-galling mite Aceria parapopuli. Three main findings emerged: (1) Strong genetic differentiation of mite populations found on pure P. angustifolia and F(1) type hybrids indicates that these mites represent morphologically cryptic species. (2) Within the F(1) type hybrids, population genetic analyses indicate migration among individual trees; however, (3) transfer experiments show that the mites found on heavily infested F(1) type trees perform best on their natal host genotype, suggesting that genetic interactions between mites and their host trees drive population structure, local adaptation, and host race formation. These findings argue that hybridization and genotypic differences in foundation tree species may drive herbivore population structure, and have evolutionary consequences for dependent arthropod species.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18752612?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Shan, Wen-Juan</style></author><author><style face="normal" font="default" size="100%">Tong, Chun-Fa</style></author><author><style face="normal" font="default" size="100%">Shi, Ji-Sen</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Comparison of statistical methods for detecting differential expression in microarray data].</style></title><secondary-title><style face="normal" font="default" size="100%">Yi chuan = Hereditas / Zhongguo yi chuan xue hui bian ji</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Yi Chuan</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">30</style></volume><pages><style face="normal" font="default" size="100%">1640-6</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">DNA microarray is a new tool in biotechnology, which allows simultaneously monitoring thousands of gene expression in cells. The goal of differential gene expression analysis is to detect genes with significant change of gene expression levels arising from experimental conditions. Although various statistical methods have been suggested to confirm differential gene expression, only a few studies compared performance of the statistical methods. This paper presented comparison of statistical methods for finding differentially expressed genes (DEGs) from the microarray data. Using simulated and real datasets (Populus cDNA microarray data), we compared eight methods of identifying differential gene expression. The simulated datasets included four differential distributions (normal distribution, uniform distribution, c2 distribution, and exponential distribution). The results of simulated datasets analysis showed that the eight methods were more preferable with the microarray data of uniform distribution than normal distribution. They were not preferable with the c2 distribution and exponential distribution. Of these eight methods, SAM (Significance Analysis of Microarrays) and Wilcoxon rank sum test performed well in most cases. The results of real cDNA microarray data of Populus showed that there was much similarity of SAM, Samroc, and regression modeling approach. Wilcoxon rank sum test was different from them. Samroc and regression modeling approach were similar in the eight methods. For both simulated and real datasets, SAM, Samroc, and regression modeling approach performed better than other methods.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19073583?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhao, Chuan-yan</style></author><author><style face="normal" font="default" size="100%">Li, Shou-bo</style></author><author><style face="normal" font="default" size="100%">Jia, Yan-hong</style></author><author><style face="normal" font="default" size="100%">Jiang, Yun-chao</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Dynamic changes of groundwater level and vegetation in water table fluctuant belt in lower reaches of Heihe River: coupling simulation].</style></title><secondary-title><style face="normal" font="default" size="100%">Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ying Yong Sheng Tai Xue Bao</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">19</style></volume><pages><style face="normal" font="default" size="100%">2687-92</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Based on the 2006 investigation data in lower reaches of Heihe River, and by using logarithmic normal distribution model, the models about the vegetation cover of Populus euphratica and Tamarix ramossima and the groundwater level in study area were built, and the potential plant of the study area was simulated. The results showed that in the lower reaches of Heihe River, the optimal groundwater level and mean groundwater level for P. euphratica were 2.6 m and 3.6 m, and those for T. ramossima were 2.0 m and 3.0 m, respectively. The high cover P. euphratica distribution area was mainly concentrated in the near-banks of Donghe River and Xihe River, while higher cover T. ramossima was distributed in most parts of the study area. From the aspect of current groundwater level, T. ramossima should be the adaptive species in the study area. The similarities between the potential and actual spatial distribution of P. euphratica and T. ramossima were 43. 4% and 55. 6% , respectively, and the main reason for the lower similarity was that there existed a gypsum salt pan in soil, which blocked the vertical movement of soil water.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19288724?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhao, Yu-tao</style></author><author><style face="normal" font="default" size="100%">Li, Xue-feng</style></author><author><style face="normal" font="default" size="100%">Han, Shi-jie</style></author><author><style face="normal" font="default" size="100%">Hu, Yan-ling</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Soil enzyme activities under two forest types as affected by different levels of nitrogen deposition].</style></title><secondary-title><style face="normal" font="default" size="100%">Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ying Yong Sheng Tai Xue Bao</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">19</style></volume><pages><style face="normal" font="default" size="100%">2769-73</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A simulation test was conducted to study the change trends of soil cellulase, polyphenol oxidase, and sucrase activities under natural broadleaf-Korean pine (Pinus koraiensis) and secondary poplar (Populus davidiana) -birch (Betula platyphylla) mixed forests as affected by 0, 25, and 50 kg x hm(-2) x a(-1) of N deposition. The results showed that the effects of elevated N deposition on test enzyme activities varied with forest type, and short-term nitrogen addition could significantly affect the test enzyme activities. High N deposition decreased soil polyphyneol oxidase activity, and correspondingly, soil cellulase and sucrase activities also had a trend of decrease.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19288737?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Saura-Valls, Marc</style></author><author><style face="normal" font="default" size="100%">Fauré, Régis</style></author><author><style face="normal" font="default" size="100%">Brumer, Harry</style></author><author><style face="normal" font="default" size="100%">Teeri, Tuula T</style></author><author><style face="normal" font="default" size="100%">Cottaz, Sylvain</style></author><author><style face="normal" font="default" size="100%">Driguez, Hugues</style></author><author><style face="normal" font="default" size="100%">Planas, Antoni</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Active-site mapping of a Populus xyloglucan endo-transglycosylase with a library of xylogluco-oligosaccharides.</style></title><secondary-title><style face="normal" font="default" size="100%">The Journal of biological chemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Biol. Chem.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Aug 8</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">283</style></volume><pages><style face="normal" font="default" size="100%">21853-63</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Restructuring the network of xyloglucan (XG) and cellulose during plant cell wall morphogenesis involves the action of xyloglucan endo-transglycosylases (XETs). They cleave the XG chains and transfer the enzyme-bound XG fragment to another XG molecule, thus allowing transient loosening of the cell wall and also incorporation of nascent XG during expansion. The substrate specificity of a XET from Populus (PttXET16-34) has been analyzed by mapping the enzyme binding site with a library of xylogluco-oligosaccharides as donor substrates using a labeled heptasaccharide as acceptor. The extended binding cleft of the enzyme is composed of four negative and three positive subsites (with the catalytic residues between subsites -1 and +1). Donor binding is dominated by the higher affinity of the XXXG moiety (G=Glcbeta(1--&gt;4) and X=Xylalpha(1--&gt;6)Glcbeta(1--&gt;4)) of the substrate for positive subsites, whereas negative subsites have a more relaxed specificity, able to bind (and transfer to the acceptor) a cello-oligosaccharyl moiety of hybrid substrates such as GGGGXXXG. Subsite mapping with k(cat)/K(m) values for the donor substrates showed that a GG-unit on negative and -XXG on positive subsites are the minimal requirements for activity. Subsites -2 and -3 (for backbone Glc residues) and +2' (for Xyl substitution at Glc in subsite +2) have the largest contribution to transition state stabilization. GalGXXXGXXXG (Gal=Galbeta(1--&gt;4)) is the best donor substrate with a &quot;blocked&quot; nonreducing end that prevents polymerization reactions and yields a single transglycosylation product. Its kinetics have unambiguously established that the enzyme operates by a ping-pong mechanism with competitive inhibition by the acceptor.</style></abstract><issue><style face="normal" font="default" size="100%">32</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18511421?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Piens, Kathleen</style></author><author><style face="normal" font="default" size="100%">Fauré, Régis</style></author><author><style face="normal" font="default" size="100%">Sundqvist, Gustav</style></author><author><style face="normal" font="default" size="100%">Baumann, Martin J</style></author><author><style face="normal" font="default" size="100%">Saura-Valls, Marc</style></author><author><style face="normal" font="default" size="100%">Teeri, Tuula T</style></author><author><style face="normal" font="default" size="100%">Cottaz, Sylvain</style></author><author><style face="normal" font="default" size="100%">Planas, Antoni</style></author><author><style face="normal" font="default" size="100%">Driguez, Hugues</style></author><author><style face="normal" font="default" size="100%">Brumer, Harry</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Mechanism-based labeling defines the free energy change for formation of the covalent glycosyl-enzyme intermediate in a xyloglucan endo-transglycosylase.</style></title><secondary-title><style face="normal" font="default" size="100%">The Journal of biological chemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Biol. Chem.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Aug 8</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">283</style></volume><pages><style face="normal" font="default" size="100%">21864-72</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Xyloglucan endo-transglycosylases (XETs) are key enzymes involved in the restructuring of plant cell walls during morphogenesis. As members of glycoside hydrolase family 16 (GH16), XETs are predicted to employ the canonical retaining mechanism of glycosyl transfer involving a covalent glycosyl-enzyme intermediate. Here, we report the accumulation and direct observation of such intermediates of PttXET16-34 from hybrid aspen by electrospray mass spectrometry in combination with synthetic &quot;blocked&quot; substrates, which function as glycosyl donors but are incapable of acting as glycosyl acceptors. Thus, GalGXXXGGG and GalGXXXGXXXG react with the wild-type enzyme to yield relatively stable, kinetically competent, covalent GalG-enzyme and GalGXXXG-enzyme complexes, respectively (Gal=Galbeta(1--&gt;4), G=Glcbeta(1--&gt;4), and X=Xylalpha(1--&gt;6)Glcbeta(1--&gt;4)). Quantitation of ratios of protein and saccharide species at pseudo-equilibrium allowed us to estimate the free energy change (DeltaG(0)) for the formation of the covalent GalGXXXG-enzyme as 6.3-8.5 kJ/mol (1.5-2.0 kcal/mol). The data indicate that the free energy of the beta(1--&gt;4) glucosidic bond in xyloglucans is preserved in the glycosyl-enzyme intermediate and harnessed for religation of the polysaccharide in vivo.</style></abstract><issue><style face="normal" font="default" size="100%">32</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18508770?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Krom, Nicholas</style></author><author><style face="normal" font="default" size="100%">Ramakrishna, Wusirika</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Comparative analysis of divergent and convergent gene pairs and their expression patterns in rice, Arabidopsis, and populus.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">147</style></volume><pages><style face="normal" font="default" size="100%">1763-73</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Comparative analysis of the organization and expression patterns of divergent and convergent gene pairs in multiple plant genomes can identify patterns that are shared by more than one species or are unique to a particular species. Here, we study the coexpression and interspecies conservation of divergent and convergent gene pairs in three plant species: rice (Oryza sativa), Arabidopsis (Arabidopsis thaliana), and black cottonwood (Populus trichocarpa). Strongly correlated expression levels between divergent and convergent genes were found to be quite common in all three species, and the frequency of strong correlation appears to be independent of intergenic distance. Conservation of divergent or convergent arrangement among these species appears to be quite rare. However, conserved arrangement is significantly more frequent when the genes display strongly correlated expression levels or have one or more Gene Ontology (GO) classes in common. A correlation between intergenic distance in divergent and convergent gene pairs and shared GO classes was observed, in varying degrees, in rice and Populus but not in Arabidopsis. Furthermore, multiple GO classes were either overrepresented or underrepresented in Arabidopsis and Populus gene pairs, while only two GO classes were underrepresented in rice divergent gene pairs. Three cis-regulatory elements common to both Arabidopsis and rice were overrepresented in the intergenic regions of strongly correlated divergent gene pairs compared to those of noncorrelated pairs. Our results suggest that shared as well as unique mechanisms operate in shaping the organization and function of divergent and convergent gene pairs in different plant species.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18515639?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Urban, Otmar</style></author><author><style face="normal" font="default" size="100%">Sprtová, Mirka</style></author><author><style face="normal" font="default" size="100%">Kosvancová, Martina</style></author><author><style face="normal" font="default" size="100%">Tomásková, Ivana</style></author><author><style face="normal" font="default" size="100%">Lichtenthaler, Hartmut K</style></author><author><style face="normal" font="default" size="100%">Marek, Michal V</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Comparison of photosynthetic induction and transient limitations during the induction phase in young and mature leaves from three poplar clones.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">1189-97</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We tested the hypothesis that leaf age affects photosynthetic induction, because conductance to CO2 diffusion usually decreases with increasing leaf age. Photosynthetic inductions, primarily determined by the light modulation of Rubisco activity and stomatal opening, were investigated in both young and mature leaves, as defined by leaf plastochron index (LPI), from three poplar clones: Populus alba L., P. nigra L. and P. x euramericana (Dode) Guinier. In all clones, maximum assimilation rates (A max), maximum stomatal conductance (G Smax) and dark respiration rates (RD) were higher in young leaves (LPI = 3-5) than in mature leaves (LPI = 10-14), and A max decreased from P. alba via P. x euramericana to P. nigra. The clones with high photosynthetic capacity had low induction states 60 s after leaf illumination (IS60; indicating a slow initial induction phase), and required less time to reach 90% photosynthetic induction (T90). In contrast, the clone with the lowest photosynthetic capacity (P. nigra) exhibited high IS60 (high initial induction state) but a long induction time (high T90). A comparison of mature leaves with young leaves revealed significantly (P &lt; 0.01) lower IS60 values in mature leaves of P. nigra only, and significantly higher T90 values in mature leaves of P. alba only. In all clones, young leaves exhibited a lower percentage of maximum transient stomatal limitation during photosynthetic induction (4-9%) compared with mature leaves (16-30%). Transient biochemical limitation, assessed on the basis of the time constants of Rubisco activation (tau), was significantly higher in mature leaves than in young leaves of P. alba; whereas there were no significant differences in tau between young and mature leaves of the other poplar clones. Thus, our hypothesis that leaf age affects photosynthetic induction was confirmed at the level of transient stomatal limitation, which was significantly higher in mature leaves than in young leaves in all clones. For the induction parameters IS60, T90 and tau, photosynthetic induction was more clone-specific and was dependent on leaf age only in some cases, an observation that may apply to other tree species.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18519250?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Li, Jingyi</style></author><author><style face="normal" font="default" size="100%">Brunner, Amy M</style></author><author><style face="normal" font="default" size="100%">Shevchenko, Olga</style></author><author><style face="normal" font="default" size="100%">Meilan, Richard</style></author><author><style face="normal" font="default" size="100%">Ma, Cathleen</style></author><author><style face="normal" font="default" size="100%">Skinner, Jeffrey S</style></author><author><style face="normal" font="default" size="100%">Strauss, Steven H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Efficient and stable transgene suppression via RNAi in field-grown poplars.</style></title><secondary-title><style face="normal" font="default" size="100%">Transgenic research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Transgenic Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">17</style></volume><pages><style face="normal" font="default" size="100%">679-94</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The efficiency and stability of RNA interference (RNAi) in perennial species, particularly in natural environments, is poorly understood. We studied 56 independent poplar RNAi transgenic events in the field over 2 years. A resident BAR transgene was targeted with two different types of RNAi constructs: a 475-bp IR of the promoter sequence and a 275-bp IR of the coding sequence, each with and without the presence of flanking matrix attachment regions (MARs). RNAi directed at the coding sequence was a strong inducer of gene silencing; 80% of the transgenic events showed more than 90% suppression. In contrast, RNAi targeting the promoter resulted in only 6% of transgenic events showing more than 90% suppression. The degree of suppression varied widely but was highly stable in each event over 2 years in the field, and had no association with insert copy number or the presence of MARs. RNAi remained stable during a winter to summer seasonal cycle, a time when expression of the targeted transgene driven by an rbcS promoter varied widely. When strong gene suppression was induced by an IR directed at the promoter sequence, it was accompanied by methylation of the homologous promoter region. DNA methylation was also observed in the coding region of highly suppressed events containing an IR directed at the coding sequence; however, the methylation degree and pattern varied widely among those suppressed events. Our results suggest that RNAi can be highly effective for functional genomics and biotechnology of perennial plants.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17929189?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Arend, Matthias</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Immunolocalization of (1,4)-beta-galactan in tension wood fibers of poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">1263-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The occurrence and distribution of (1,4)-beta-galactan in wood cells of poplar (Populus trichocarpa Torr. &amp; A. Gray x P. koreana Rehder) were studied by immunolabeling with a monoclonal antibody (LM5) specific to this carbohydrate epitope. Immunofluorescence microscopy revealed exclusive binding of the LM5 antibody to tension wood fibers, indicating the specific presence of (1,4)-beta-galactan in cell walls of this wood cell type. Higher magnifications achieved with the fluorescence microscope and additional immunogold electron microscopy showed that the binding of the LM5 antibody was mainly restricted to a narrow cell wall area between the gelatinous G-layer and the secondary cell wall. This labeling pattern strongly suggests a role of (1,4)-beta-galactan in cross-linking the G-layer and secondary cell wall. Furthermore, the exclusive localization of (1,4)-beta-galactan in tension wood strengthens the view that this carbohydrate epitope can be considered a highly specific marker of reaction wood formation in mechanically stressed trees.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18519257?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wagner, Diane</style></author><author><style face="normal" font="default" size="100%">DeFoliart, Linda</style></author><author><style face="normal" font="default" size="100%">Doak, Patricia</style></author><author><style face="normal" font="default" size="100%">Schneiderheinze, Jenny</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Impact of epidermal leaf mining by the aspen leaf miner (Phyllocnistis populiella) on the growth, physiology, and leaf longevity of quaking aspen.</style></title><secondary-title><style face="normal" font="default" size="100%">Oecologia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Oecologia</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">157</style></volume><pages><style face="normal" font="default" size="100%">259-67</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The aspen leaf miner, Phyllocnistis populiella, feeds on the contents of epidermal cells on both top (adaxial) and bottom (abaxial) surfaces of quaking aspen leaves, leaving the photosynthetic tissue of the mesophyll intact. This type of feeding is taxonomically restricted to a small subset of leaf mining insects but can cause widespread plant damage during outbreaks. We studied the effect of epidermal mining on aspen growth and physiology during an outbreak of P. populiella in the boreal forest of interior Alaska. Experimental reduction of leaf miner density across two sites and 3 years significantly increased annual aspen growth rates relative to naturally mined controls. Leaf mining damage was negatively related to leaf longevity. Leaves with heavy mining damage abscised 4 weeks earlier, on average, than leaves with minimal mining damage. Mining damage to the top and bottom surfaces of leaves had different effects on physiology. Mining on the top surface of the leaf had no significant effect on photosynthesis or conductance and was unrelated to leaf stable C isotope ratio (delta(13)C). Mining damage to the bottom leaf surface, where stomata are located, had significant negative effects on net photosynthesis and water vapor conductance. Percent bottom mining was positively related to leaf delta(13)C. Taken together, the data suggest that the primary mechanism for the reduction of photosynthesis by epidermal leaf mining by P. populiella is the failure of stomata to open normally on bottom-mined leaves.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18523809?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gierlinger, Notburga</style></author><author><style face="normal" font="default" size="100%">Goswami, Luna</style></author><author><style face="normal" font="default" size="100%">Schmidt, Martin</style></author><author><style face="normal" font="default" size="100%">Burgert, Ingo</style></author><author><style face="normal" font="default" size="100%">Coutand, Catherine</style></author><author><style face="normal" font="default" size="100%">Rogge, Tilmann</style></author><author><style face="normal" font="default" size="100%">Schwanninger, Manfred</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">In situ FT-IR microscopic study on enzymatic treatment of poplar wood cross-sections.</style></title><secondary-title><style face="normal" font="default" size="100%">Biomacromolecules</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biomacromolecules</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">2194-201</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The feasibility of Fourier transform infrared (FT-IR) microscopy to monitor in situ the enzymatic degradation of wood was investigated. Cross-sections of poplar wood were treated with cellulase Onozuka RS within a custom-built fluidic cell. Light-optical micrographs and FT-IR spectra were acquired in situ from normal and tension wood fibers. Light-optical micrographs showed almost complete removal of the gelatinous (G) layer in tension wood. No structural and spectral changes were observed in the lignified cell walls. The accessibility of cellulose within the lignified cell wall was found to be the main limiting factor, whereas the depletion of the enzyme due to lignin adsorption could be ruled out. The fast, selective hydrolysis of the crystalline cellulose in the G-layer, even at room temperature, might be explained by the gel-like structure and the highly porous surface. Young plantation grown hardwood trees with a high proportion of G-fibers thus represent an interesting resource for bioconversion to fermentable sugars in the process to bioethanol.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18636773?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Fortunati, Alessio</style></author><author><style face="normal" font="default" size="100%">Barta, Csengele</style></author><author><style face="normal" font="default" size="100%">Brilli, Federico</style></author><author><style face="normal" font="default" size="100%">Centritto, Mauro</style></author><author><style face="normal" font="default" size="100%">Zimmer, Ina</style></author><author><style face="normal" font="default" size="100%">Schnitzler, Jörg-Peter</style></author><author><style face="normal" font="default" size="100%">Loreto, Francesco</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Isoprene emission is not temperature-dependent during and after severe drought-stress: a physiological and biochemical analysis.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">55</style></volume><pages><style face="normal" font="default" size="100%">687-97</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">SUMMARY: Black poplar (Populus nigra L.) plants grown at 25 and 35 degrees C were subjected to drought stress to assess the combined impact of two consequences of global climate change--rising temperature and drought--on isoprene biosynthesis and emission. At both temperatures, photosynthesis was inhibited by moderate drought, but isoprene emission only decreased when drought was prolonged. The mRNA transcript level, protein concentration and activity of isoprene synthase (ISPS) changed in concert with isoprene emission during drought stress. However, ISPS activity decreased before isoprene emission during drought development, indicating a tighter control of the emission at a transcriptional or post-transcriptional level under moderate drought stress, and at both temperatures. A residual isoprene emission was measured when photosynthesis was totally inhibited after 35 days of drought. This photosynthesis-independent emission of isoprene was probably dependent on a cytosolic carbon supply as all the properties of ISPS were drastically inhibited. Isoprene emission was associated with dark respiration during the entire drought stress period, and at both temperatures, indicating that the two processes are sustained by, but do not compete for, the same carbon source. Isoprene emission was directly related to phosphoenolpyruvate carboxylase activity in plants grown at 25 degrees C and inversely related in plants grown at 35 degrees C, suggesting a strong temperature control on the regulation of the pyruvate flowing from the cytosol to the plastidic isoprenoid biosynthetic pathway under drought stress and recovery. In re-watered plants, the temperature control on isoprene emission was suppressed, despite complete recovery of photosynthesis and ISPS activity similar to levels in plants subjected to mild drought stress. Our results reveal the overriding effects of drought on isoprene emission, possibly affecting protein level or substrate supply. These effects may largely offset the predicted impact of rising temperatures on the emission of isoprene in terrestrial ecosystems.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18445130?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gutierrez, Laurent</style></author><author><style face="normal" font="default" size="100%">Mauriat, Mélanie</style></author><author><style face="normal" font="default" size="100%">Guénin, Stéphanie</style></author><author><style face="normal" font="default" size="100%">Pelloux, Jérôme</style></author><author><style face="normal" font="default" size="100%">Lefebvre, Jean-François</style></author><author><style face="normal" font="default" size="100%">Louvet, Romain</style></author><author><style face="normal" font="default" size="100%">Rusterucci, Christine</style></author><author><style face="normal" font="default" size="100%">Moritz, Thomas</style></author><author><style face="normal" font="default" size="100%">Guerineau, François</style></author><author><style face="normal" font="default" size="100%">Bellini, Catherine</style></author><author><style face="normal" font="default" size="100%">Van Wuytswinkel, Olivier</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The lack of a systematic validation of reference genes: a serious pitfall undervalued in reverse transcription-polymerase chain reaction (RT-PCR) analysis in plants.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant biotechnology journal</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Biotechnol. J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">6</style></volume><pages><style face="normal" font="default" size="100%">609-18</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Reverse transcription-polymerase chain reaction (RT-PCR) approaches have been used in a large proportion of transcriptome analyses published to date. The accuracy of the results obtained by this method strongly depends on accurate transcript normalization using stably expressed genes, known as references. Statistical algorithms have been developed recently to help validate reference genes, and most studies of gene expression in mammals, yeast and bacteria now include such validation. Surprisingly, this important approach is under-utilized in plant studies, where putative housekeeping genes tend to be used as references without any appropriate validation. Using quantitative RT-PCR, the expression stability of several genes commonly used as references was tested in various tissues of Arabidopsis thaliana and hybrid aspen (Populus tremula x Populus tremuloides). It was found that the expression of most of these genes was unstable, indicating that their use as references is inappropriate. The major impact of the use of such inappropriate references on the results obtained by RT-PCR is demonstrated in this study. Using aspen as a model, evidence is presented indicating that no gene can act as a universal reference, implying the need for a systematic validation of reference genes. For the first time, the extent to which the lack of a systematic validation of reference genes is a stumbling block to the reliability of results obtained by RT-PCR in plants is clearly shown.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18433420?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Moore, Tim R</style></author><author><style face="normal" font="default" size="100%">Trofymow, J A</style></author><author><style face="normal" font="default" size="100%">Siltanen, M</style></author><author><style face="normal" font="default" size="100%">Kozak, L M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Litter decomposition and nitrogen and phosphorus dynamics in peatlands and uplands over 12 years in central Canada.</style></title><secondary-title><style face="normal" font="default" size="100%">Oecologia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Oecologia</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">157</style></volume><pages><style face="normal" font="default" size="100%">317-25</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The large accumulation of organic matter in peatlands has been partially attributed to litter decomposition rates, which are slowed by a high water table. To test this, we examined whether there were significant differences in the decomposition and N and P dynamics of ten foliar litters and wood blocks at three pairs of upland forest and peatland sites in the transitional grassland, high boreal and low subarctic regions of central Canada, using litterbags collected over a 12-year period. At two of the three pairs, the decomposition rate, as determined by proportion of the original mass remaining after 12 years and by the exponential decay coefficient (k), was faster overall at the upland than at the peatland. In the third pair, there was no significant difference, despite the water table being close to the peat surface; warmer soil temperatures in the peatland than the upland may be the cause. In general, there were small losses or gains of N in the litters after 12 years, compared to the original litter, though there were some differences among litter types and sites, net gains in N likely reflecting the higher exogenous N availability. P was lost from most litters at the two northern pairs of sites, but at the transitional grassland pair, there were large net gains in P and greater variation among litters. The N:P ratio in the original litters ranged from 5 to 26 and after 12 years the ratio narrowed, with the site average of the ten litters ranging from 13 to 22, varying with the soil ratio. Decomposition rates and N and P dynamics after 12 years are different between upland and peatland sites: although the water table is a primary control on these differences, other factors such as temperature and soil nutrient status are also important.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18560899?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kumazawa, Shigenori</style></author><author><style face="normal" font="default" size="100%">Nakamura, Jun</style></author><author><style face="normal" font="default" size="100%">Murase, Masayo</style></author><author><style face="normal" font="default" size="100%">Miyagawa, Mariko</style></author><author><style face="normal" font="default" size="100%">Ahn, Mok-Ryeon</style></author><author><style face="normal" font="default" size="100%">Fukumoto, Shuichi</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Plant origin of Okinawan propolis: honeybee behavior observation and phytochemical analysis.</style></title><secondary-title><style face="normal" font="default" size="100%">Die Naturwissenschaften</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Naturwissenschaften</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">95</style></volume><pages><style face="normal" font="default" size="100%">781-6</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Propolis is a natural resinous product collected by honeybees from certain plants. It has gained popularity as a food and alternative medicine. Poplar and Baccharis are well known as the source plants of European and Brazilian propolis, respectively. However, the propolis from Okinawa, Japan, contains some prenylflavonoids not seen in other regions such as Europe and Brazil, suggesting that the plant origin of Okinawan propolis is a particular plant that grows in Okinawa. To identify the plant origin of Okinawan propolis, we observed the behavior of honeybees as they collected material from plants and caulked it inside the hive. Honeybees scraped resinous material from the surface of plant fruits of Macaranga tanarius and brought it back to their hive to use it as propolis. We collected samples of the plant and propolis, and compared their constituents by high-performance liquid chromatography with a photo-diode array detector. We also compared their 1,1-diphenyl-2-picryl-hydrazyl radical scavenging activity. The chemical constituents and biological activity of the ethanol extracts of the plant did not differ from those of propolis. This indicates directly that the plant origin of Okinawan propolis is M. tanarius.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18427763?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Uddling, Johan</style></author><author><style face="normal" font="default" size="100%">Teclaw, Ronald M</style></author><author><style face="normal" font="default" size="100%">Kubiske, Mark E</style></author><author><style face="normal" font="default" size="100%">Pregitzer, Kurt S</style></author><author><style face="normal" font="default" size="100%">Ellsworth, David S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Sap flux in pure aspen and mixed aspen-birch forests exposed to elevated concentrations of carbon dioxide and ozone.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">1231-43</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Elevated concentrations of atmospheric carbon dioxide ([CO2]) and tropospheric ozone ([O3]) have the potential to affect tree physiology and structure and hence forest water use, which has implications for climate feedbacks. We investigated how a 40% increase above ambient values in [CO2] and [O3], alone and in combination, affect tree water use of pure aspen and mixed aspen-birch forests in the free air CO2-O3 enrichment experiment near Rhinelander, Wisconsin (Aspen FACE). Measurements of sap flux and canopy leaf area index (L) were made during two growing seasons, when steady-state L had been reached after more than 6 years of exposure to elevated [CO2] and [O3]. Maximum stand-level sap flux was not significantly affected by elevated [O3], but was increased by 18% by elevated [CO2] averaged across years, communities and O(3) regimes. Treatment effects were similar in pure aspen and mixed aspen-birch communities. Increased tree water use in response to elevated [CO2] was related to positive CO2 treatment effects on tree size and L (+40%). Tree water use was not reduced by elevated [O3] despite strong negative O3 treatment effects on tree size and L (-22%). Elevated [O3] predisposed pure aspen stands to drought-induced sap flux reductions, whereas increased tree water use in response to elevated [CO2] did not result in lower soil water content in the upper soil or decreasing sap flux relative to control values during dry periods. Maintenance of soil water content in the upper soil in the elevated [CO2] treatment was at least partly a function of enhanced soil water-holding capacity, probably a result of increased organic matter content from increased litter inputs. Our findings that larger trees growing in elevated [CO2] used more water and that tree size, but not maximal water use, was negatively affected by elevated [O3] suggest that the long-term cumulative effects on stand structure may be more important than the expected primary stomatal closure responses to elevated [CO2] and [O3] in determining stand-level water use under possible future atmospheric conditions.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18519254?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bandyopadhyay, Sibali</style></author><author><style face="normal" font="default" size="100%">Gama, Filipe</style></author><author><style face="normal" font="default" size="100%">Molina-Navarro, Maria Micaela</style></author><author><style face="normal" font="default" size="100%">Gualberto, José Manuel</style></author><author><style face="normal" font="default" size="100%">Claxton, Ronald</style></author><author><style face="normal" font="default" size="100%">Naik, Sunil G</style></author><author><style face="normal" font="default" size="100%">Huynh, Boi Hanh</style></author><author><style face="normal" font="default" size="100%">Herrero, Enrique</style></author><author><style face="normal" font="default" size="100%">Jacquot, Jean Pierre</style></author><author><style face="normal" font="default" size="100%">Johnson, Michael K</style></author><author><style face="normal" font="default" size="100%">Rouhier, Nicolas</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Chloroplast monothiol glutaredoxins as scaffold proteins for the assembly and delivery of [2Fe-2S] clusters.</style></title><secondary-title><style face="normal" font="default" size="100%">The EMBO journal</style></secondary-title><alt-title><style face="normal" font="default" size="100%">EMBO J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Apr 9</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">27</style></volume><pages><style face="normal" font="default" size="100%">1122-33</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Glutaredoxins (Grxs) are small oxidoreductases that reduce disulphide bonds or protein-glutathione mixed disulphides. More than 30 distinct grx genes are expressed in higher plants, but little is currently known concerning their functional diversity. This study presents biochemical and spectroscopic evidence for incorporation of a [2Fe-2S] cluster in two heterologously expressed chloroplastic Grxs, GrxS14 and GrxS16, and in vitro cysteine desulphurase-mediated assembly of an identical [2Fe-2S] cluster in apo-GrxS14. These Grxs possess the same monothiol CGFS active site as yeast Grx5 and both were able to complement a yeast grx5 mutant defective in Fe-S cluster assembly. In vitro kinetic studies monitored by CD spectroscopy indicate that [2Fe-2S] clusters on GrxS14 are rapidly and quantitatively transferred to apo chloroplast ferredoxin. These data demonstrate that chloroplast CGFS Grxs have the potential to function as scaffold proteins for the assembly of [2Fe-2S] clusters that can be transferred intact to physiologically relevant acceptor proteins. Alternatively, they may function in the storage and/or delivery of preformed Fe-S clusters or in the regulation of the chloroplastic Fe-S cluster assembly machinery.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18354500?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kim, Hyun-Seok</style></author><author><style face="normal" font="default" size="100%">Oren, Ram</style></author><author><style face="normal" font="default" size="100%">Hinckley, Thomas M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Actual and potential transpiration and carbon assimilation in an irrigated poplar plantation.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">559-77</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We examined the tradeoffs between stand-level water use and carbon uptake that result when biomass production of trees in plantations is maximized by removing nutrient and water limitations. A Populus trichocarpa Torr. x P. deltoides Bartr. &amp; Marsh. plantation was irrigated and received frequent additions of nutrients to optimize biomass production. Sap flux density was measured continuously over four of the six growing-season months, supplemented with periodic measurements of leaf gas exchange and water potential. Measurements of tree diameter and height were used to estimate leaf area and biomass production based on allometric relationships. Sap flux was converted to canopy conductance and analyzed with an empirical model to isolate the effects of water limitation. Actual and soil-water-unlimited potential CO(2) uptakes were estimated with a canopy conductance constrained carbon assimilation (4C-A) scheme, which couples actual or potential canopy conductance with vertical gradients of light distribution, leaf-level conductance, maximum Rubisco capacity and maximum electron transport. Net primary production (NPP) was about 43% of gross primary production (GPP); when estimated for individual trees, this ratio was independent of tree size. Based on the NPP/GPP ratio, we found that current irrigation reduced growth by about 18% compared with growth with no water limitation. To achieve maximum growth, however, would require 70% more water for transpiration, and would reduce water-use efficiency by 27%, from 1.57 to 1.15 g stem wood C kg(-1) water. Given the economic and social values of water, plantation managers appear to have optimized water use.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18244943?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Winters, Anna M</style></author><author><style face="normal" font="default" size="100%">Bolling, Bethany G</style></author><author><style face="normal" font="default" size="100%">Beaty, Barry J</style></author><author><style face="normal" font="default" size="100%">Blair, Carol D</style></author><author><style face="normal" font="default" size="100%">Eisen, Rebecca J</style></author><author><style face="normal" font="default" size="100%">Meyer, Andrew M</style></author><author><style face="normal" font="default" size="100%">Pape, W John</style></author><author><style face="normal" font="default" size="100%">Moore, Chester G</style></author><author><style face="normal" font="default" size="100%">Eisen, Lars</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Combining mosquito vector and human disease data for improved assessment of spatial West Nile virus disease risk.</style></title><secondary-title><style face="normal" font="default" size="100%">The American journal of tropical medicine and hygiene</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Am. J. Trop. Med. Hyg.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">78</style></volume><pages><style face="normal" font="default" size="100%">654-65</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Assessments of spatial risk of exposure to vector-borne pathogens that combine vector and human disease data are needed for areas encompassing large tracts of public land with low population bases. We addressed this need for West Nile virus (WNV) disease in the northern Colorado Front Range by developing not only a spatial model for entomological risk of exposure to Culex tarsalis WNV vectors and an epidemiological risk map for WNV disease but also a novel risk-classification index combining data for these independently derived measures of entomological and epidemiological risk. Risk of vector exposure was high in the densely populated eastern plains portion of the Front Range but low in cooler montane areas to the west that are sparsely populated but used heavily for recreation in the summer. The entomological risk model performed well when applied to the western, mountainous part of Colorado and validated against epidemiologic data.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18385365?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lesaulnier, Celine</style></author><author><style face="normal" font="default" size="100%">Papamichail, Dimitris</style></author><author><style face="normal" font="default" size="100%">McCorkle, Sean</style></author><author><style face="normal" font="default" size="100%">Ollivier, Bernard</style></author><author><style face="normal" font="default" size="100%">Skiena, Steven</style></author><author><style face="normal" font="default" size="100%">Taghavi, Safiyh</style></author><author><style face="normal" font="default" size="100%">Zak, Donald</style></author><author><style face="normal" font="default" size="100%">van der Lelie, Daniel</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Elevated atmospheric CO2 affects soil microbial diversity associated with trembling aspen.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental microbiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Microbiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">10</style></volume><pages><style face="normal" font="default" size="100%">926-41</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The effects of elevated atmospheric CO(2) (560 p.p.m.) and subsequent plant responses on the soil microbial community composition associated with trembling aspen was assessed through the classification of 6996 complete ribosomal DNA sequences amplified from the Rhinelander WI free-air CO(2) and O(3) enrichment (FACE) experiments microbial community metagenome. This in-depth comparative analysis provides an unprecedented, detailed and deep branching profile of population changes incurred as a response to this environmental perturbation. Total bacterial and eukaryotic abundance does not change; however, an increase in heterotrophic decomposers and ectomycorrhizal fungi is observed. Nitrate reducers of the domain bacteria and archaea, of the phylum Crenarchaea, potentially implicated in ammonium oxidation, significantly decreased with elevated CO(2). These changes in soil biota are evidence for altered interactions between trembling aspen and the microorganisms in its surrounding soil, and support the theory that greater plant detritus production under elevated CO(2) significantly alters soil microbial community composition.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18218029?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kohler, Annegret</style></author><author><style face="normal" font="default" size="100%">Rinaldi, Cécile</style></author><author><style face="normal" font="default" size="100%">Duplessis, Sébastien</style></author><author><style face="normal" font="default" size="100%">Baucher, Marie</style></author><author><style face="normal" font="default" size="100%">Geelen, Danny</style></author><author><style face="normal" font="default" size="100%">Duchaussoy, Frédéric</style></author><author><style face="normal" font="default" size="100%">Meyers, Blake C</style></author><author><style face="normal" font="default" size="100%">Boerjan, Wout</style></author><author><style face="normal" font="default" size="100%">Martin, Francis</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genome-wide identification of NBS resistance genes in Populus trichocarpa.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Mol. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">66</style></volume><pages><style face="normal" font="default" size="100%">619-36</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">As the largest class of disease resistance R genes, the genes encoding nucleotide binding site and leucine-rich repeat proteins (&quot;NBS-LRR genes&quot;) play a critical role in defending plants from a multitude of pathogens and pests. The diversity of NBS-LRR genes was examined in the Populus trichocarpa draft genome sequence. The NBS class of genes in this perennial tree is large and diverse, comprised of approximately 400 genes, at least twice the complement of Arabidopsis. The NBS family can be divided into multiple subfamilies with distinct domain organizations. It includes 119 Coiled-Coil-NBS-LRR genes, 64 TIR-NBS-LRR genes, 34 BED-finger-NBS-LRR, and both truncated and unusual NBS- and NBS-LRR-containing genes. The transcripts of only 34 NBS-LRR genes were detected in rust-infected and non-infected leaves using a whole-genome oligoarray. None showed an altered expression two days post inoculation.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18247136?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Brunner, Ivano</style></author><author><style face="normal" font="default" size="100%">Luster, Jörg</style></author><author><style face="normal" font="default" size="100%">Günthardt-Goerg, Madeleine S</style></author><author><style face="normal" font="default" size="100%">Frey, Beat</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Heavy metal accumulation and phytostabilisation potential of tree fine roots in a contaminated soil.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">152</style></volume><pages><style face="normal" font="default" size="100%">559-68</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Root systems of Norway spruce (Picea abies) and poplar (Populus tremula) were long-term exposed to metal-contaminated soils in open-top chambers to investigate the accumulation of the heavy metals in the fine roots and to assess the plants suitability for phytostabilisation. The heavy metals from the contaminated soil accumulated in the fine roots about 10-20 times more than in the controls. The capacity to bind heavy metals already reached its maximum after the first vegetation period. Fine roots of spruce tend to accumulate more heavy metals than poplar. Copper and Zinc were mainly detected in the cell walls with larger values in the epidermis than in the cortex. The heavy metals accumulated in the fine roots made up 0.03-0.2% of the total amount in the soils. We conclude that tree fine roots adapt well to conditions with heavy metal contamination, but their phytostabilisation capabilities seem to be very low.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17707113?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hoenicka, Hans</style></author><author><style face="normal" font="default" size="100%">Nowitzki, Olaf</style></author><author><style face="normal" font="default" size="100%">Hanelt, Dieter</style></author><author><style face="normal" font="default" size="100%">Fladung, Matthias</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Heterologous overexpression of the birch FRUITFULL-like MADS-box gene BpMADS4 prevents normal senescence and winter dormancy in Populus tremula L.</style></title><secondary-title><style face="normal" font="default" size="100%">Planta</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Planta</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">227</style></volume><pages><style face="normal" font="default" size="100%">1001-11</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">MADS-box genes have been shown to be important to flower and vegetative tissue development, senescence and winter dormancy in many plant species. Heterologous overexpression of known MADS-box genes has also been used for unravelling gene regulation mechanisms in forest tree species. The constitutive expression of the BpMADS4 gene from birch in poplar, known to induce early flowering in birch and apple, induced broad changes in senescence and winter dormancy but no early flowering. Other analyses revealed that 35S::BpMADS4 poplars maintained photosynthetic activity, chlorophyll and proteins in leaves under winter conditions. BpMADS4 may be influencing transcription factors regulating the senescence and dormancy process due to homology with poplar proteins related to both traits. Little is known of the regulatory genes that co-ordinate senescence, dormancy, chlorophyll/protein degradation, and photosynthesis at the molecular level. Dissecting the molecular characteristics of senescence regulation will probably involve the understanding of multiple and novel regulatory pathways. The results presented here open new horizons for the identification of regulatory mechanisms related to dormancy and senescence in poplar and other temperate tree species. They confirm recent reports of common signalling intermediates between flowering time and growth cessation in trees (Böhlenius et al. in Science 312:1040-1043, 2006) and additionally indicate similar connections between flowering time signals and senescence.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18185941?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ingvarsson, Pär K</style></author><author><style face="normal" font="default" size="100%">Garcia, M Victoria</style></author><author><style face="normal" font="default" size="100%">Luquez, Virginia</style></author><author><style face="normal" font="default" size="100%">Hall, David</style></author><author><style face="normal" font="default" size="100%">Jansson, Stefan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Nucleotide polymorphism and phenotypic associations within and around the phytochrome B2 Locus in European aspen (Populus tremula, Salicaceae).</style></title><secondary-title><style face="normal" font="default" size="100%">Genetics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Genetics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">178</style></volume><pages><style face="normal" font="default" size="100%">2217-26</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We investigated the utility of association mapping to dissect the genetic basis of naturally occurring variation in bud phenology in European aspen (Populus tremula). With this aim, we surveyed nucleotide polymorphism in 13 fragments spanning an 80-kb region surrounding the phytochrome B2 (phyB2) locus. Although polymorphism varies substantially across the phyB2 region, we detected no signs for deviations from neutral expectations. We also identified a total of 41 single nucleotide polymorphisms (SNPs) that were subsequently scored in a mapping population consisting of 120 trees. We identified two nonsynonymous SNPs in the phytochrome B2 gene that were independently associated with variation in the timing of bud set and that explained between 1.5 and 5% of the observed phenotypic variation in bud set. Earlier studies have shown that the frequencies of both these SNPs vary clinally with latitude. Linkage disequilibrium across the region was low, suggesting that the SNPs we identified are strong candidates for being causally linked to variation in bud set in our mapping populations. One of the SNPs (T608N) is located in the &quot;hinge region,&quot; close to the chromophore binding site of the phyB2 protein. The other SNP (L1078P) is located in a region supposed to mediate downstream signaling from the phyB2 locus. The lack of population structure, combined with low levels of linkage disequilibrium, suggests that association mapping is a fruitful method for dissecting naturally occurring variation in Populus tremula.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18245834?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rahimi, Ali Reza</style></author><author><style face="normal" font="default" size="100%">Emad, Maryam</style></author><author><style face="normal" font="default" size="100%">Rezaian, Gholam Reza</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Smoke from leaves of Populus euphratica Olivier vs. conventional cryotherapy for the treatment of cutaneous warts: a pilot, randomized, single-blind, prospective study.</style></title><secondary-title><style face="normal" font="default" size="100%">International journal of dermatology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Int. J. Dermatol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">47</style></volume><pages><style face="normal" font="default" size="100%">393-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Populous euphratica tree which belongs to Salicaceae family is naturally distributed in many parts of the world. Our purpose was to compare the therapeutic effects of smoke of its burnt leaves with conventional cryotherapy in patients with warts.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18377608?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ralph, Steven G</style></author><author><style face="normal" font="default" size="100%">Chun, Hye Jung E</style></author><author><style face="normal" font="default" size="100%">Cooper, Dawn</style></author><author><style face="normal" font="default" size="100%">Kirkpatrick, Robert</style></author><author><style face="normal" font="default" size="100%">Kolosova, Natalia</style></author><author><style face="normal" font="default" size="100%">Gunter, Lee</style></author><author><style face="normal" font="default" size="100%">Tuskan, Gerald A</style></author><author><style face="normal" font="default" size="100%">Douglas, Carl J</style></author><author><style face="normal" font="default" size="100%">Holt, Robert A</style></author><author><style face="normal" font="default" size="100%">Jones, Steven J M</style></author><author><style face="normal" font="default" size="100%">Marra, Marco A</style></author><author><style face="normal" font="default" size="100%">Bohlmann, Jörg</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Analysis of 4,664 high-quality sequence-finished poplar full-length cDNA clones and their utility for the discovery of genes responding to insect feeding.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC genomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">57</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The genus Populus includes poplars, aspens and cottonwoods, which will be collectively referred to as poplars hereafter unless otherwise specified. Poplars are the dominant tree species in many forest ecosystems in the Northern Hemisphere and are of substantial economic value in plantation forestry. Poplar has been established as a model system for genomics studies of growth, development, and adaptation of woody perennial plants including secondary xylem formation, dormancy, adaptation to local environments, and biotic interactions.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18230180?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ríos, Gabino</style></author><author><style face="normal" font="default" size="100%">Naranjo, Miguel A</style></author><author><style face="normal" font="default" size="100%">Iglesias, Domingo J</style></author><author><style face="normal" font="default" size="100%">Ruiz-Rivero, Omar</style></author><author><style face="normal" font="default" size="100%">Geraud, Marion</style></author><author><style face="normal" font="default" size="100%">Usach, Antonio</style></author><author><style face="normal" font="default" size="100%">Talón, Manuel</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Characterization of hemizygous deletions in citrus using array-comparative genomic hybridization and microsynteny comparisons with the poplar genome.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC genomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">381</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Many fruit-tree species, including relevant Citrus spp varieties exhibit a reproductive biology that impairs breeding and strongly constrains genetic improvements. In citrus, juvenility increases the generation time while sexual sterility, inbreeding depression and self-incompatibility prevent the production of homozygous cultivars. Genomic technology may provide citrus researchers with a new set of tools to address these various restrictions. In this work, we report a valuable genomics-based protocol for the structural analysis of deletion mutations on an heterozygous background.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18691431?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">van Loo, Marcela</style></author><author><style face="normal" font="default" size="100%">Joseph, Jeffrey A</style></author><author><style face="normal" font="default" size="100%">Heinze, Berthold</style></author><author><style face="normal" font="default" size="100%">Fay, Mike F</style></author><author><style face="normal" font="default" size="100%">Lexer, Christian</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Clonality and spatial genetic structure in Populus x canescens and its sympatric backcross parent P. alba in a Central European hybrid zone.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">177</style></volume><pages><style face="normal" font="default" size="100%">506-16</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Spatial genetic structure (SGS) holds the key to understanding the role of clonality in hybrid persistence, but multilocus SGS in hybrid zones has rarely been quantified. Here, the aim was to fill this gap for natural hybrids between two diploid, ecologically divergent European tree species with mixed sexual/asexual reproduction, Populus alba and P. tremula. Nuclear microsatellites were used to quantify clonality, SGS, and historical gene dispersal distances in up to 407 trees from an extensive Central European hybrid zone including three subpopulation replicates. The focus was on P. x canescens and its backcross parent P. alba, as these two genotypic classes co-occur and interact directly. Sexual recombination in both taxa was more prominent than previously thought, but P. x canescens hybrids tended to build larger clones extending over larger areas than P. alba. The 3.4 times stronger SGS in the P. x canescens genet population was best explained by a combination of interspecific gene flow, assortative mating, and increased clonality in hybrids. Clonality potentially contributes to the maintenance of hybrid zones of P. alba and P. tremula in time and space. Both clonality and SGS need to be taken into account explicitly when designing population genomics studies of locus-specific effects in hybrid zones.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18005320?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wolf, Maxim Y</style></author><author><style face="normal" font="default" size="100%">Wolf, Yuri I</style></author><author><style face="normal" font="default" size="100%">Koonin, Eugene V</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Comparable contributions of structural-functional constraints and expression level to the rate of protein sequence evolution.</style></title><secondary-title><style face="normal" font="default" size="100%">Biology direct</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biol. Direct</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">3</style></volume><pages><style face="normal" font="default" size="100%">40</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Proteins show a broad range of evolutionary rates. Understanding the factors that are responsible for the characteristic rate of evolution of a given protein arguably is one of the major goals of evolutionary biology. A long-standing general assumption used to be that the evolution rate is, primarily, determined by the specific functional constraints that affect the given protein. These constrains were traditionally thought to depend both on the specific features of the protein's structure and its biological role. The advent of systems biology brought about new types of data, such as expression level and protein-protein interactions, and unexpectedly, a variety of correlations between protein evolution rate and these variables have been observed. The strongest connections by far were repeatedly seen between protein sequence evolution rate and the expression level of the respective gene. It has been hypothesized that this link is due to the selection for the robustness of the protein structure to mistranslation-induced misfolding that is particularly important for highly expressed proteins and is the dominant determinant of the sequence evolution rate.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18840284?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Creux, Nicole Marie</style></author><author><style face="normal" font="default" size="100%">Ranik, Martin</style></author><author><style face="normal" font="default" size="100%">Berger, David Kenneth</style></author><author><style face="normal" font="default" size="100%">Myburg, Alexander Andrew</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Comparative analysis of orthologous cellulose synthase promoters from Arabidopsis, Populus and Eucalyptus: evidence of conserved regulatory elements in angiosperms.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">179</style></volume><pages><style face="normal" font="default" size="100%">722-37</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">* The cellulose synthase (CesA) gene family encodes the catalytic subunits of a large protein complex responsible for the deposition of cellulose into plant cell walls. Early in vascular plant evolution, the gene family diverged into distinct members with conserved structures and functions (e.g. primary or secondary cell wall biosynthesis). Although the functions and expression domains of CesA genes have been extensively studied in plants, little is known about transcriptional regulation and promoter evolution in this gene family. * Here, comparative sequence analysis of orthologous CesA promoters from three angiosperm genera, Arabidopsis, Populus and Eucalyptus, was performed to identify putative cis-regulatory sequences. The promoter sequences of groups of Arabidopsis genes that are co-expressed with the primary or secondary cell wall-related CesA genes were also analyzed. * Reporter gene analysis of newly isolated promoter regions of six E. grandis CesA genes in Arabidopsis revealed the conserved functionality of the promoter sequences. Comparative sequence analysis identified 71 conserved sequence motifs, of which 66 were significantly over-represented in either primary or secondary wall-associated promoters. * The presence of conserved cis-regulatory elements in the evolutionary distant CesA promoters of Arabidopsis, Populus and Eucalyptus suggests an ancient transcriptional network regulating cellulose biosynthesis in vascular plants.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18547376?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Quesada, Tania</style></author><author><style face="normal" font="default" size="100%">Li, Zhen</style></author><author><style face="normal" font="default" size="100%">Dervinis, Christopher</style></author><author><style face="normal" font="default" size="100%">Li, Yao</style></author><author><style face="normal" font="default" size="100%">Bocock, Philip N</style></author><author><style face="normal" font="default" size="100%">Tuskan, Gerald A</style></author><author><style face="normal" font="default" size="100%">Casella, George</style></author><author><style face="normal" font="default" size="100%">Davis, John M</style></author><author><style face="normal" font="default" size="100%">Kirst, Matias</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Comparative analysis of the transcriptomes of Populus trichocarpa and Arabidopsis thaliana suggests extensive evolution of gene expression regulation in angiosperms.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">180</style></volume><pages><style face="normal" font="default" size="100%">408-20</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Sequencing of the Populus trichocarpa genome creates an opportunity to describe the transcriptome of a woody perennial species and establish an atlas of gene expression. A comparison with the transcriptomes of other species can also define genes that are conserved or diverging in plant species. Here, the transcriptome in vegetative organs of the P. trichocarpa reference genotype Nisqually-1 was characterized. A comparison with Arabidopsis thaliana orthologs was used to distinguish gene functional categories that may be evolving differently in a woody perennial and an annual herbaceous species. A core set of genes expressed in common among vegetative organs was detected, as well as organ-specific genes. Statistical tests identified chromatin domains, where adjacent genes were expressed more frequently than expected by chance. Extensive divergence was detected in the expression patterns of A. thaliana and P. trichocarpa orthologs, but transcription of a small number of genes appeared to have remained conserved in the two species. Despite separation of lineages for over 100 million yr, these results suggest that selection has limited transcriptional divergence of genes associated with some essential functions in A. thaliana and P. trichocarpa. However, extensive remodeling of transcriptional networks indicates that expression regulation may be a key determinant of plant diversity.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18694447?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Street, Nathaniel Robert</style></author><author><style face="normal" font="default" size="100%">Sjödin, Andreas</style></author><author><style face="normal" font="default" size="100%">Bylesjö, Max</style></author><author><style face="normal" font="default" size="100%">Gustafsson, Petter</style></author><author><style face="normal" font="default" size="100%">Trygg, Johan</style></author><author><style face="normal" font="default" size="100%">Jansson, Stefan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A cross-species transcriptomics approach to identify genes involved in leaf development.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC genomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">589</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We have made use of publicly available gene expression data to identify transcription factors and transcriptional modules (regulons) associated with leaf development in Populus. Different tissue types were compared to identify genes informative in the discrimination of leaf and non-leaf tissues. Transcriptional modules within this set of genes were identified in a much wider set of microarray data collected from leaves in a number of developmental, biotic, abiotic and transgenic experiments.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19061504?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Jokipii, Soile</style></author><author><style face="normal" font="default" size="100%">Häggman, Hely</style></author><author><style face="normal" font="default" size="100%">Brader, Günter</style></author><author><style face="normal" font="default" size="100%">Kallio, Pauli T</style></author><author><style face="normal" font="default" size="100%">Niemi, Karoliina</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Endogenous PttHb1 and PttTrHb, and heterologous Vitreoscilla vhb haemoglobin gene expression in hybrid aspen roots with ectomycorrhizal interaction.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of experimental botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Exp. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">59</style></volume><pages><style face="normal" font="default" size="100%">2449-59</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Present knowledge on plant non-symbiotic class-1 (Hb1) and truncated (TrHb) haemoglobin genes is almost entirely based on herbaceous species while the corresponding tree haemoglobin genes are not well known. The function of these genes has recently been linked with endosymbioses between plants and microbes. In this work, the coding sequences of hybrid aspen (Populus tremulaxtremuloides) PttHb1 and PttTrHb were characterized, indicating that the key residues of haem and ligand binding of both genes were conserved in the deduced amino acid sequences. The expression of PttHb1 and PttTrHb was examined in parallel with that of the heterologous Vitreoscilla haemoglobin gene (vhb) during ectomycorrhiza/ectomycorrhizal (ECM) interaction. Both ECM fungi studied, Leccinum populinum and Xerocomus subtomentosus, enhanced root formation and subsequent growth of roots of all hybrid aspen lines, but only L. populinum was able to form mycorrhizas. Real-time PCR results show that the dual culture with the ECM fungus, with or without emergence of symbiotic structures, increased the expression of both PttHb1 and PttTrHb in the roots of non-transgenic hybrid aspens. PttHb1 and PttTrHb had expression peaks 5 h and 2 d after inoculation, respectively, pointing to different functions for these genes during interaction with root growth-improving fungi. In contrast, ECM fungi were not able to enhance the expression of hybrid aspen endogenous haemoglobin genes in the VHb lines, which may be a consequence of the compensating action of heterologous haemoglobin.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18544611?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Souza, Clarice de Azevedo</style></author><author><style face="normal" font="default" size="100%">Barbazuk, Brad</style></author><author><style face="normal" font="default" size="100%">Ralph, Steven G</style></author><author><style face="normal" font="default" size="100%">Bohlmann, Joerg</style></author><author><style face="normal" font="default" size="100%">Hamberger, Bjoern</style></author><author><style face="normal" font="default" size="100%">Douglas, Carl J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genome-wide analysis of a land plant-specific acyl:coenzyme A synthetase (ACS) gene family in Arabidopsis, poplar, rice and Physcomitrella.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">179</style></volume><pages><style face="normal" font="default" size="100%">987-1003</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The plant enzyme 4-coumarate:coenzyme A ligase (4CL) is part of a family of adenylate-forming enzymes present in all organisms. Analysis of genome sequences shows the presence of '4CL-like' enzymes in plants and other organisms, but their evolutionary relationships and functions remain largely unknown. 4CL and 4CL-like genes were identified by BLAST searches in Arabidopsis, Populus, rice, Physcomitrella, Chlamydomonas and microbial genomes. Evolutionary relationships were inferred by phylogenetic analysis of aligned amino acid sequences. Expression patterns of a conserved set of Arabidopsis and poplar 4CL-like acyl-CoA synthetase (ACS) genes were assayed. The conserved ACS genes form a land plant-specific class. Angiosperm ACS genes grouped into five clades, each of which contained representatives in three fully sequenced genomes. Expression analysis revealed conserved developmental and stress-induced expression patterns of Arabidopsis and poplar genes in some clades. Evolution of plant ACS enzymes occurred early in land plants. Differential gene expansion of angiosperm ACS clades has occurred in some lineages. Evolutionary and gene expression data, combined with in vitro and limited in vivo protein function data, suggest that angiosperm ACS enzymes play conserved roles in octadecanoid and fatty acid metabolism, and play roles in organ development, for example in anthers.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18627494?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sjödin, Andreas</style></author><author><style face="normal" font="default" size="100%">Wissel, Kirsten</style></author><author><style face="normal" font="default" size="100%">Bylesjö, Max</style></author><author><style face="normal" font="default" size="100%">Trygg, Johan</style></author><author><style face="normal" font="default" size="100%">Jansson, Stefan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Global expression profiling in leaves of free-growing aspen.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC plant biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Plant Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">8</style></volume><pages><style face="normal" font="default" size="100%">61</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Genomic studies are routinely performed on young plants in controlled environments which is very different from natural conditions. In reality plants in temperate countries are exposed to large fluctuations in environmental conditions, in the case of perennials over several years. We have studied gene expression in leaves of a free-growing aspen (Populus tremula) throughout multiple growing seasons</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18500984?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Calfapietra, Carlo</style></author><author><style face="normal" font="default" size="100%">Mugnozza, Giuseppe Scarascia</style></author><author><style face="normal" font="default" size="100%">Karnosky, David F</style></author><author><style face="normal" font="default" size="100%">Loreto, Francesco</style></author><author><style face="normal" font="default" size="100%">Sharkey, Thomas D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Isoprene emission rates under elevated CO2 and O3 in two field-grown aspen clones differing in their sensitivity to O3.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">179</style></volume><pages><style face="normal" font="default" size="100%">55-61</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Isoprene is the most important nonmethane hydrocarbon emitted by plants. The role of isoprene in the plant is not entirely understood but there is evidence that it might have a protective role against different oxidative stresses originating from heat shock and/or exposure to ozone (O(3)). Thus, plants under stress conditions might benefit by constitutively high or by higher stress-induced isoprene emission rates. In this study, measurements are presented of isoprene emission from aspen (Populus tremuloides) trees grown in the field for several years under elevated CO(2) and O(3). Two aspen clones were investigated: the O(3)-tolerant 271 and the O(3)-sensitive 42E. Isoprene emission decreased significantly both under elevated CO(2) and under elevated O(3) in the O(3)-sensitive clone, but only slightly in the O(3)-tolerant clone. This study demonstrates that long-term-adapted plants are not able to respond to O(3) stress by increasing their isoprene emission rates. However, O(3)-tolerant clones have the capacity to maintain higher amounts of isoprene emission. It is suggested that tolerance to O(3) is explained by a combination of different factors; while the reduction of O(3) uptake is likely to be the most important, the capacity to maintain higher amounts of isoprene is an important factor in strengthening this character.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18557875?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Martin, Francis</style></author><author><style face="normal" font="default" size="100%">Selosse, Marc-André</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The Laccaria genome: a symbiont blueprint decoded.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">180</style></volume><pages><style face="normal" font="default" size="100%">296-310</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The first genomic sequence for a representative of symbiotic fungi, the ectomycorrhizal basidiomycete Laccaria bicolor, has been published. The unravelling of this genome provides tantalizing hints about differences between this symbiotic fungus and its saprotrophic and pathogenic relatives. An expansion of several multigene families occurred in L. bicolor, suggesting that adaptation to symbiosis proceeded by gene duplication. Within lineage-specific genes those coding for symbiosis-regulated secreted proteins showed an up-regulated expression in ectomycorrhizas. L. bicolor is lacking enzymes involved in the degradation of plant cell wall components (cellulose, hemicellulose, pectins and pectates), preventing the symbiont from degrading host cells. By contrast, L. bicolor possesses expanded multigene families associated with hydrolysis of bacterial and microfauna polysaccharides and proteins. The genome analysis revealed the dual saprotrophic and biotrophic lifestyle of the mycorrhizal fungus that enables it to grow within both soil and living plant roots. The next stages will involve finer-scale investigation of gene networks to reveal the details of the general patterns now uncovered at the genomic level. The acceptance of L. bicolor as a model organism for symbiosis genetics will, however, depend strongly on the availability of additional genetic, genomic and molecular biological resources, such as gene inactivation procedures.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19138220?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bylesjö, Max</style></author><author><style face="normal" font="default" size="100%">Segura, Vincent</style></author><author><style face="normal" font="default" size="100%">Soolanayakanahally, Raju Y</style></author><author><style face="normal" font="default" size="100%">Rae, Anne M</style></author><author><style face="normal" font="default" size="100%">Trygg, Johan</style></author><author><style face="normal" font="default" size="100%">Gustafsson, Petter</style></author><author><style face="normal" font="default" size="100%">Jansson, Stefan</style></author><author><style face="normal" font="default" size="100%">Street, Nathaniel R</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">LAMINA: a tool for rapid quantification of leaf size and shape parameters.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC plant biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Plant Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">8</style></volume><pages><style face="normal" font="default" size="100%">82</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">An increased understanding of leaf area development is important in a number of fields: in food and non-food crops, for example short rotation forestry as a biofuels feedstock, leaf area is intricately linked to biomass productivity; in paleontology leaf shape characteristics are used to reconstruct paleoclimate history. Such fields require measurement of large collections of leaves, with resulting conclusions being highly influenced by the accuracy of the phenotypic measurement process.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18647399?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Goué, Nadia</style></author><author><style face="normal" font="default" size="100%">Lesage-Descauses, Marie-Claude</style></author><author><style face="normal" font="default" size="100%">Mellerowicz, Ewa J</style></author><author><style face="normal" font="default" size="100%">Magel, Elisabeth</style></author><author><style face="normal" font="default" size="100%">Label, Philippe</style></author><author><style face="normal" font="default" size="100%">Sundberg, Björn</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Microgenomic analysis reveals cell type-specific gene expression patterns between ray and fusiform initials within the cambial meristem of Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">180</style></volume><pages><style face="normal" font="default" size="100%">45-56</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The vascular cambium is the meristem in trees that produce wood. This meristem consists of two types of neighbouring initials: fusiform cambial cells (FCCs), which give rise to the axial cell system (i.e. fibres and vessel elements), and ray cambial cells (RCCs), which give rise to rays. There is little molecular information on the mechanisms whereby the differing characteristics of these neighbouring cells are maintained. A microgenomic approach was adopted in which the transcriptomes of FCCs and RCCs dissected out from the cambial meristem of poplar (Populus trichocarpa x Populus deltoïdes var. Boelare) were analysed, and a transcriptional database for these two cell types established. Photosynthesis genes were overrepresented in RCCs, providing molecular support for the presence of photosynthetic systems in rays. Genes that putatively encode transporters (vesicle, lipid and metal ion transporters and aquaporins) in RCCs were also identified. In addition, many cell wall-related genes showed cell type-specific expression patterns. Notably, genes involved in pectin metabolism and xyloglucan metabolism were overrepresented in RCCs and FCCs, respectively. The results demonstrate the use of microgenomics to reveal differences in biological processes in neighbouring meristematic cells, and to identify key genes involved in these processes.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18631289?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ingvarsson, Pär K</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Molecular evolution of synonymous codon usage in Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC evolutionary biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Evol. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">8</style></volume><pages><style face="normal" font="default" size="100%">307</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Evolution of synonymous codon usage is thought to be determined by a balance between mutation, genetic drift and natural selection on translational efficiency. However, natural selection on codon usage is considered to be a weak evolutionary force and selection on codon usage is expected to be strongest in species with large effective population sizes.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18983655?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">De Boeck, H J</style></author><author><style face="normal" font="default" size="100%">Liberloo, M</style></author><author><style face="normal" font="default" size="100%">Gielen, B</style></author><author><style face="normal" font="default" size="100%">Nijs, I</style></author><author><style face="normal" font="default" size="100%">Ceulemans, R</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The observer effect in plant science.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">177</style></volume><pages><style face="normal" font="default" size="100%">579-83</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18086224?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Frost, Christopher J</style></author><author><style face="normal" font="default" size="100%">Mescher, Mark C</style></author><author><style face="normal" font="default" size="100%">Dervinis, Christopher</style></author><author><style face="normal" font="default" size="100%">Davis, John M</style></author><author><style face="normal" font="default" size="100%">Carlson, John E</style></author><author><style face="normal" font="default" size="100%">De Moraes, Consuelo M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Priming defense genes and metabolites in hybrid poplar by the green leaf volatile cis-3-hexenyl acetate.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">180</style></volume><pages><style face="normal" font="default" size="100%">722-34</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">* Herbivore-induced plant volatiles (HIPVs), in addition to attracting natural enemies of herbivores, can serve a signaling function within plants to induce or prime defenses. However, it is largely unknown, particularly in woody plants, which volatile compounds within HIPV blends can act as signaling molecules. * Leaves of hybrid poplar saplings were exposed in vivo to naturally wound-emitted concentrations of the green leaf volatile (GLV) cis-3-hexenyl acetate (z3HAC) and then subsequently fed upon by gypsy moth larvae. Volatiles were collected throughout the experiments, and leaf tissue was collected to measure phytohormone concentrations and expression of defense-related genes. * Relative to controls, z3HAC-exposed leaves had higher concentrations of jasmonic acid and linolenic acid following gypsy moth feeding. Furthermore, z3HAC primed transcripts of genes that mediate oxylipin signaling and direct defenses, as determined by both qRT-PCR and microarray analysis using the AspenDB 7 K expressed sequence tags (EST) microarray containing c. 5400 unique gene models. Moreover, z3HAC primed the release of terpene volatiles. * The widespread priming response suggests an adaptive benefit to detecting z3HAC as a wound signal. Thus, woody plants can detect and use z3HAC as a signal to prime defenses before actually experiencing damage. GLVs may therefore have important ecological functions in arboreal ecosystems.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18721163?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Jansson, Stefan</style></author><author><style face="normal" font="default" size="100%">Thomas, Howard</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Senescence: developmental program or timetable?</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">179</style></volume><pages><style face="normal" font="default" size="100%">575-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18433431?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Pregitzer, Kurt S</style></author><author><style face="normal" font="default" size="100%">Burton, Andrew J</style></author><author><style face="normal" font="default" size="100%">King, John S</style></author><author><style face="normal" font="default" size="100%">Zak, Donald R</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Soil respiration, root biomass, and root turnover following long-term exposure of northern forests to elevated atmospheric CO2 and tropospheric O3.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">180</style></volume><pages><style face="normal" font="default" size="100%">153-61</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The Rhinelander free-air CO(2) enrichment (FACE) experiment is designed to understand ecosystem response to elevated atmospheric carbon dioxide (+CO(2)) and elevated tropospheric ozone (+O(3)). The objectives of this study were: to understand how soil respiration responded to the experimental treatments; to determine whether fine-root biomass was correlated to rates of soil respiration; and to measure rates of fine-root turnover in aspen (Populus tremuloides) forests and determine whether root turnover might be driving patterns in soil respiration. Soil respiration was measured, root biomass was determined, and estimates of root production, mortality and biomass turnover were made. Soil respiration was greatest in the +CO(2) and +CO(2) +O(3) treatments across all three plant communities. Soil respiration was correlated with increases in fine-root biomass. In the aspen community, annual fine-root production and mortality (g m(-2)) were positively affected by +O(3). After 10 yr of exposure, +CO(2) +O(3)-induced increases in belowground carbon allocation suggest that the positive effects of elevated CO(2) on belowground net primary productivity (NPP) may not be offset by negative effects of O(3). For the aspen community, fine-root biomass is actually stimulated by +O(3), and especially +CO(2) +O(3).</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18643941?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ow, Lai Fern</style></author><author><style face="normal" font="default" size="100%">Griffin, Kevin L</style></author><author><style face="normal" font="default" size="100%">Whitehead, David</style></author><author><style face="normal" font="default" size="100%">Walcroft, Adrian S</style></author><author><style face="normal" font="default" size="100%">Turnbull, Matthew H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Thermal acclimation of leaf respiration but not photosynthesis in Populus deltoides x nigra.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">178</style></volume><pages><style face="normal" font="default" size="100%">123-34</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Dark respiration and photosynthesis were measured in leaves of poplar Populus deltoides x nigra ('Veronese') saplings to investigate the extent of respiratory and photosynthetic acclimation in pre-existing and newly emerged leaves to abrupt changes in air temperature. The saplings were grown at three temperature regimes and at high and low nitrogen availabilities. Rates of photosynthesis and dark respiration (R(d)) were measured at the initial temperature and the saplings were then transferred to a different temperature regime, where the plants remained for a second and third round of measurements on pre-existing and newly emerged leaves. Acclimation of photosynthesis was limited following transfer to warmer or cooler growing conditions. There was strong evidence of cold and warm acclimation of R(d) to growth temperature, but this was limited in pre-existing leaves. Full acclimation of R(d )was restricted to newly emerged leaves grown at the new growth temperature. These findings indicate that the extent of thermal acclimation differs significantly between photosynthesis and respiration. Importantly, pre-existing leaves in poplar were capable of some respiratory acclimation, but full acclimation was observed only in newly emerged leaves. The R(d)/A(max) ratio declined at higher growth temperatures, and nitrogen status of leaves had little impact on the degree of acclimation.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18221247?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ramírez-Carvajal, Gustavo A</style></author><author><style face="normal" font="default" size="100%">Morse, Alison M</style></author><author><style face="normal" font="default" size="100%">Davis, John M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Transcript profiles of the cytokinin response regulator gene family in Populus imply diverse roles in plant development.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">177</style></volume><pages><style face="normal" font="default" size="100%">77-89</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Cytokinins are plant hormones that influence diverse processes of growth and development. In this study the cytokinin response regulators (RRs) were identified, annotated and characterized at the transcript level in Populus balsamifera ssp. trichocarpa genotype Nisqually 1. The Populus genome was searched for genes that exhibit high sequence identity across their receiver domains. Gene structure was determined by prediction software and, where possible, corroborated by publicly available expressed sequence tags (ESTs). Thirty-three genes belonging to the cytokinin RR gene family were identified in Populus: 11 type As, 11 type Bs and 11 pseudo-RRs. Developmental and cytokinin-responsive expression of the Populus RRs was assessed by whole-genome microarrays and semiquantitative reverse transcription polymerase chain reaction (RT-PCR). Populus RR type As and type Bs appear to be preferentially expressed in nodes, while pseudo-RRs are preferentially expressed in mature leaves. Seven type As and three type Bs were rapidly induced by exogenous cytokinin. Organ-preferred expression patterns suggest possible roles for type As and Bs in development and for pseudo-RRs in integration of environmental signals with plant function.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17944821?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Talbot, Nicholas J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Unwrapping the Laccaria genome.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">180</style></volume><pages><style face="normal" font="default" size="100%">259-60</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/19138214?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gookin, Timothy E</style></author><author><style face="normal" font="default" size="100%">Kim, Junhyong</style></author><author><style face="normal" font="default" size="100%">Assmann, Sarah M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Whole proteome identification of plant candidate G-protein coupled receptors in Arabidopsis, rice, and poplar: computational prediction and in-vivo protein coupling.</style></title><secondary-title><style face="normal" font="default" size="100%">Genome biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Genome Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">R120</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The classic paradigm of heterotrimeric G-protein signaling describes a heptahelical, membrane-spanning G-protein coupled receptor that physically interacts with an intracellular G alpha subunit of the G-protein heterotrimer to transduce signals. G-protein coupled receptors comprise the largest protein superfamily in metazoa and are physiologically important as they sense highly diverse stimuli and play key roles in human disease. The heterotrimeric G-protein signaling mechanism is conserved across metazoa, and also readily identifiable in plants, but the low sequence conservation of G-protein coupled receptors hampers the identification of novel ones. Using diverse computational methods, we performed whole-proteome analyses of the three dominant model plant species, the herbaceous dicot Arabidopsis thaliana (mouse-eared cress), the monocot Oryza sativa (rice), and the woody dicot Populus trichocarpa (poplar), to identify plant protein sequences most likely to be GPCRs.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18671868?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Aylott, Matthew J</style></author><author><style face="normal" font="default" size="100%">Casella, E</style></author><author><style face="normal" font="default" size="100%">Tubby, I</style></author><author><style face="normal" font="default" size="100%">Street, N R</style></author><author><style face="normal" font="default" size="100%">Smith, P</style></author><author><style face="normal" font="default" size="100%">Taylor, Gail</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Yield and spatial supply of bioenergy poplar and willow short-rotation coppice in the UK.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">178</style></volume><pages><style face="normal" font="default" size="100%">358-70</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Limited information on likely supply and spatial yield of bioenergy crops exists for the UK. Here, productivities are reported of poplar (Populus spp.) and willow (Salix spp.) grown as short-rotation coppice (SRC), using data from a large 49-site yield trial network. A partial least-squares regression technique was used to upscale actual field trial observations across England and Wales. Spatial productivity was then assessed under different land-use scenarios. Mean modelled yields ranged between 4.9 and 10.7 oven-dry tonnes (odt) ha(-1) yr(-1). Yields were generally higher in willow than in poplar, reflecting the susceptibility of older poplar genotypes to rust and their tendency for single stem dominance. Replacing 10% of arable land, 20% of improved grassland and 100% of set-aside grassland in England and Wales with the three most productive genotypes would yield 13 Modt of biomass annually (supplying 7% of UK electricity production or 48% of UK combined heat and power (CHP) production). Results show existing SRC genotypes have the immediate potential to be an important component of a mixed portfolio of renewables and that, in future, as new and improved genotypes become available, higher yields could extend this potential further.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18331429?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Jaillon, Olivier</style></author><author><style face="normal" font="default" size="100%">Aury, Jean-Marc</style></author><author><style face="normal" font="default" size="100%">Noel, Benjamin</style></author><author><style face="normal" font="default" size="100%">Policriti, Alberto</style></author><author><style face="normal" font="default" size="100%">Clepet, Christian</style></author><author><style face="normal" font="default" size="100%">Casagrande, Alberto</style></author><author><style face="normal" font="default" size="100%">Choisne, Nathalie</style></author><author><style face="normal" font="default" size="100%">Aubourg, Sébastien</style></author><author><style face="normal" font="default" size="100%">Vitulo, Nicola</style></author><author><style face="normal" font="default" size="100%">Jubin, Claire</style></author><author><style face="normal" font="default" size="100%">Vezzi, Alessandro</style></author><author><style face="normal" font="default" size="100%">Legeai, Fabrice</style></author><author><style face="normal" font="default" size="100%">Hugueney, Philippe</style></author><author><style face="normal" font="default" size="100%">Dasilva, Corinne</style></author><author><style face="normal" font="default" size="100%">Horner, David</style></author><author><style face="normal" font="default" size="100%">Mica, Erica</style></author><author><style face="normal" font="default" size="100%">Jublot, Delphine</style></author><author><style face="normal" font="default" size="100%">Poulain, Julie</style></author><author><style face="normal" font="default" size="100%">Bruyère, Clémence</style></author><author><style face="normal" font="default" size="100%">Billault, Alain</style></author><author><style face="normal" font="default" size="100%">Segurens, Béatrice</style></author><author><style face="normal" font="default" size="100%">Gouyvenoux, Michel</style></author><author><style face="normal" font="default" size="100%">Ugarte, Edgardo</style></author><author><style face="normal" font="default" size="100%">Cattonaro, Federica</style></author><author><style face="normal" font="default" size="100%">Anthouard, Véronique</style></author><author><style face="normal" font="default" size="100%">Vico, Virginie</style></author><author><style face="normal" font="default" size="100%">Del Fabbro, Cristian</style></author><author><style face="normal" font="default" size="100%">Alaux, Michaël</style></author><author><style face="normal" font="default" size="100%">Di Gaspero, Gabriele</style></author><author><style face="normal" font="default" size="100%">Dumas, Vincent</style></author><author><style face="normal" font="default" size="100%">Felice, Nicoletta</style></author><author><style face="normal" font="default" size="100%">Paillard, Sophie</style></author><author><style face="normal" font="default" size="100%">Juman, Irena</style></author><author><style face="normal" font="default" size="100%">Moroldo, Marco</style></author><author><style face="normal" font="default" size="100%">Scalabrin, Simone</style></author><author><style face="normal" font="default" size="100%">Canaguier, Aurélie</style></author><author><style face="normal" font="default" size="100%">Le Clainche, Isabelle</style></author><author><style face="normal" font="default" size="100%">Malacrida, Giorgio</style></author><author><style face="normal" font="default" size="100%">Durand, Eléonore</style></author><author><style face="normal" font="default" size="100%">Pesole, Graziano</style></author><author><style face="normal" font="default" size="100%">Laucou, Valérie</style></author><author><style face="normal" font="default" size="100%">Chatelet, Philippe</style></author><author><style face="normal" font="default" size="100%">Merdinoglu, Didier</style></author><author><style face="normal" font="default" size="100%">Delledonne, Massimo</style></author><author><style face="normal" font="default" size="100%">Pezzotti, Mario</style></author><author><style face="normal" font="default" size="100%">Lecharny, Alain</style></author><author><style face="normal" font="default" size="100%">Scarpelli, Claude</style></author><author><style face="normal" font="default" size="100%">Artiguenave, François</style></author><author><style face="normal" font="default" size="100%">Pè, M Enrico</style></author><author><style face="normal" font="default" size="100%">Valle, Giorgio</style></author><author><style face="normal" font="default" size="100%">Morgante, Michele</style></author><author><style face="normal" font="default" size="100%">Caboche, Michel</style></author><author><style face="normal" font="default" size="100%">Adam-Blondon, Anne-Françoise</style></author><author><style face="normal" font="default" size="100%">Weissenbach, Jean</style></author><author><style face="normal" font="default" size="100%">Quétier, Francis</style></author><author><style face="normal" font="default" size="100%">Wincker, Patrick</style></author></authors><translated-authors><author><style face="normal" font="default" size="100%">French-Italian Public Consortium for Grapevine Genome Characterization</style></author></translated-authors></contributors><titles><title><style face="normal" font="default" size="100%">The grapevine genome sequence suggests ancestral hexaploidization in major angiosperm phyla.</style></title><secondary-title><style face="normal" font="default" size="100%">Nature</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Nature</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Sep 27</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">449</style></volume><pages><style face="normal" font="default" size="100%">463-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The analysis of the first plant genomes provided unexpected evidence for genome duplication events in species that had previously been considered as true diploids on the basis of their genetics. These polyploidization events may have had important consequences in plant evolution, in particular for species radiation and adaptation and for the modulation of functional capacities. Here we report a high-quality draft of the genome sequence of grapevine (Vitis vinifera) obtained from a highly homozygous genotype. The draft sequence of the grapevine genome is the fourth one produced so far for flowering plants, the second for a woody species and the first for a fruit crop (cultivated for both fruit and beverage). Grapevine was selected because of its important place in the cultural heritage of humanity beginning during the Neolithic period. Several large expansions of gene families with roles in aromatic features are observed. The grapevine genome has not undergone recent genome duplication, thus enabling the discovery of ancestral traits and features of the genetic organization of flowering plants. This analysis reveals the contribution of three ancestral genomes to the grapevine haploid content. This ancestral arrangement is common to many dicotyledonous plants but is absent from the genome of rice, which is a monocotyledon. Furthermore, we explain the chronology of previously described whole-genome duplication events in the evolution of flowering plants.</style></abstract><issue><style face="normal" font="default" size="100%">7161</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17721507?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Cseke, Leland J</style></author><author><style face="normal" font="default" size="100%">Cseke, Sarah Beth</style></author><author><style face="normal" font="default" size="100%">Podila, Gopi K</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">High efficiency poplar transformation.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant cell reports</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Rep.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">26</style></volume><pages><style face="normal" font="default" size="100%">1529-38</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">With the completion of the poplar tree genome database, Populus species have become one of the most useful model systems for the study of woody plant biology. Populus tremuloides (quaking aspen) is the most wide-spread tree species in North America, and its rapid growth generates the most abundant wood-based biomass out of any other plant species. To study such beneficial traits, there is a need for easier and more efficient transformation procedures that will allow the study of large numbers of tree genes. We have developed transformation procedures that are suitable for high-throughput format transformations using either Agrobacterium tumefaciens to produce transformed trees or Agrobacterium rhizogenes to generate hairy roots. Our method uses Agrobacterium inoculated aspen seedling hypocotyls followed by direct thidiazuron (TDZ)-mediated shoot regeneration on selective media. Transformation was verified through beta-glucuronidase (GUS) reporter gene expression in all tree tissues, PCR amplification of appropriate vector products from isolated genomic DNA, and northern hybridization of incorporated and expressed transgenes. The hairy root protocol follows the same inoculation procedures and was tested using GUS reporter gene integration and antibiotic selection. The benefit of these procedures is that they are simple and efficient, requiring no maintenance of starting materials and allowing fully formed transgenic trees (or hairy roots) to be generated in only 3-4 months, rather than the 6-12 months required by more traditional methods. Likewise, the fact that the protocols are amenable to high-throughput formats makes them better suited for large-scale functional genomics studies in poplars.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17492451?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Begum, Shahanara</style></author><author><style face="normal" font="default" size="100%">Nakaba, Satoshi</style></author><author><style face="normal" font="default" size="100%">Oribe, Yuichiro</style></author><author><style face="normal" font="default" size="100%">Kubo, Takafumi</style></author><author><style face="normal" font="default" size="100%">Funada, Ryo</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Induction of cambial reactivation by localized heating in a deciduous hardwood hybrid poplar (Populus sieboldii x P. grandidentata).</style></title><secondary-title><style face="normal" font="default" size="100%">Annals of botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ann. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">100</style></volume><pages><style face="normal" font="default" size="100%">439-47</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The timing of cambial reactivation plays an important role in the control of both the quantity and the quality of wood. The effect of localized heating on cambial reactivation in the main stem of a deciduous hardwood hybrid poplar (Populus sieboldii x P. grandidentata) was investigated.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17621596?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Laisk, Agu</style></author><author><style face="normal" font="default" size="100%">Oja, Vello</style></author><author><style face="normal" font="default" size="100%">Eichelmann, Hillar</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Kinetics of leaf oxygen uptake represent in planta activities of respiratory electron transport and terminal oxidases.</style></title><secondary-title><style face="normal" font="default" size="100%">Physiologia plantarum</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Physiol Plant</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">131</style></volume><pages><style face="normal" font="default" size="100%">1-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We present, for the first time, the oxygen response kinetics of mitochondrial respiration measured in intact leaves (sunflower and aspen). Low O(2) concentrations in N(2) (9-1500 ppm) were preset in a flow-through gas exchange measurement system, and the decrease in O(2) concentration and the increase in CO(2) concentration as result of leaf respiration were measured by a zirconium cell O(2) analyser and infrared-absorption CO(2) analyser, respectively. The low O(2) concentrations little influenced the rate of CO(2) evolution during the 60-s exposure. The initial slope of the O(2) uptake curve on the dissolved O(2) concentration basis was relatively constant in leaves of a single species, 1.5 mm s(-1) in sunflower and 1.8 mm s(-1) in aspen. The apparent K(0.5)(O(2)) values ranged from 0.33 to 0.67 microM in sunflower and from 0.33 to 1.1 microM in aspen, mainly because of the variation of the maximum rate, V(max) (leaf temperature 22 degrees C). The initial slope of the O(2) response of respiration characterizes the catalytic efficiency of terminal oxidases, an important parameter of the respiratory machinery in leaves. The plateau of the response characterizes the activity of the mitochondrial electron transport chain and is subject to regulations in accordance with the necessity for ATP production. The relatively low oxygen conductivity of terminal oxidases means that in leaves, less than 10% of the photosynthetic oxygen can be reassimilated by mitochondria.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18251919?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Barakat, Abdelali</style></author><author><style face="normal" font="default" size="100%">Wall, Kerr</style></author><author><style face="normal" font="default" size="100%">Leebens-Mack, Jim</style></author><author><style face="normal" font="default" size="100%">Wang, Yunjiao J</style></author><author><style face="normal" font="default" size="100%">Carlson, John E</style></author><author><style face="normal" font="default" size="100%">Depamphilis, Claude W</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Large-scale identification of microRNAs from a basal eudicot (Eschscholzia californica) and conservation in flowering plants.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">51</style></volume><pages><style face="normal" font="default" size="100%">991-1003</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">MicroRNAs (miRNAs) negatively control gene expression by cleaving or inhibiting the translation of mRNA of target genes, and as such, they play an important role in plant development. Of the 79 plant miRNA families discovered to date, most are from the fully sequenced plant genomes of Arabidopsis, Populus and rice. Here, we identified miRNAs from leaves, roots, stems and flowers at different developmental stages of the basal eudicot species Eschscholzia californica (California poppy) using cloning and capillary sequencing, as well as ultrahigh-throughput pyrosequencing using the recently introduced 454 sequencing method. In total, we identified a minimum of 173 unique miRNA sequences belonging to 28 miRNA families and seven trans-acting small interfering RNAs (ta-siRNAs) conserved in eudicot and monocot species. miR529 and miR537, which have not yet been reported in eudicot species, were detected in California poppy; loci encoding these miRNAs were also found in Arabidopsis and Populus. miR535, which occurs in the moss Physcomitrella patens, was also detected in California poppy, but not in other angiosperms. Several potential miRNA targets were found in cDNA sequences of California poppy. Predicted target genes include transcription factors but also genes implicated in various metabolic processes and in stress defense. Comparative analysis of miRNAs from plants of phylogenetically-critical basal lineages aid the study of the evolutionary gains and losses of miRNAs in plants as well as their conservation, and lead to discoveries about the miRNAs of even well-studied model organisms.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17635767?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wu, Yuxia</style></author><author><style face="normal" font="default" size="100%">Ding, Nan</style></author><author><style face="normal" font="default" size="100%">Zhao, Xin</style></author><author><style face="normal" font="default" size="100%">Zhao, Mingui</style></author><author><style face="normal" font="default" size="100%">Chang, Zongqiang</style></author><author><style face="normal" font="default" size="100%">Liu, Jianquan</style></author><author><style face="normal" font="default" size="100%">Zhang, Lixin</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Molecular characterization of PeSOS1: the putative Na(+)/H (+) antiporter of Populus euphratica.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Mol. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">65</style></volume><pages><style face="normal" font="default" size="100%">1-11</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Populus euphratica is a salt-tolerant tree species growing in semi-arid saline areas. A Na(+)/H(+) antiporter gene was successfully isolated from this species through RACE cloning, and named PeSOS1. The isolated cDNA was 3665 bp long and contained a 3438 bp open reading frame that was predicted to encode a 127-kDa protein with 12 hypothetical transmembrane domains in the N-terminal part and a long hydrophilic cytoplasmic tail in the C-terminal part. The amino acid sequence of this PeSOS1 gene showed 64% identity with the previously isolated SOS1 gene from the glycophyte Arabidopsis thaliana. The level of protein expressed by PeSOS1 in the leaves of P. euphratica was significantly up-regulated in the presence of high (200 mM) concentrations of NaCl, while the mRNA level in the leaves remained relatively constant. Immunoanalysis suggested that the protein encoded by PeSOS1 is localized in the plasma membrane. Expression of PeSOS1 partially suppressed the salt sensitive phenotypes of the EP432 bacterial strain, which lacks the activity of the two Na(+)/H(+) antiporters EcNhaA and EcNhaB. These results suggest that PeSOS1 may play an essential role in the salt tolerance of P. euphratica and may be useful for improving salt tolerance in other tree species.</style></abstract><issue><style face="normal" font="default" size="100%">1-2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17605111?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Yang, Yongqing</style></author><author><style face="normal" font="default" size="100%">Hu, Lei</style></author><author><style face="normal" font="default" size="100%">Chen, Xuemei</style></author><author><style face="normal" font="default" size="100%">Ottow, Eric A</style></author><author><style face="normal" font="default" size="100%">Polle, Andrea</style></author><author><style face="normal" font="default" size="100%">Jiang, Xiangning</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A novel method to quantify H+-ATPase-dependent Na+ transport across plasma membrane vesicles.</style></title><secondary-title><style face="normal" font="default" size="100%">Biochimica et biophysica acta</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biochim. Biophys. Acta</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">1768</style></volume><pages><style face="normal" font="default" size="100%">2078-88</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">To prevent sodium toxicity in plants, Na(+) is excluded from the cytosol to the apoplast or the vacuole by Na(+)/H(+) antiporters. The secondary active transport of Na(+) to apoplast against its electrochemical gradient is driven by plasma membrane H(+)-ATPases that hydrolyze ATP and pump H(+) across the plasma membrane. Current methods to determine Na(+) flux rely either on the use of Na-isotopes ((22)Na) which require special working permission or sophisticated equipment or on indirect methods estimating changes in the H(+) gradient due to H(+)-ATPase in the presence or absence of Na(+) by pH-sensitive probes. To date, there are no methods that can directly quantify H(+)-ATPase-dependent Na(+) transport in plasma membrane vesicles. We developed a method to measure bidirectional H(+)-ATPase-dependent Na(+) transport in isolated membrane vesicle systems using atomic absorption spectrometry (AAS). The experiments were performed using plasma membrane-enriched vesicles isolated by aqueous two-phase partitioning from leaves of Populus tomentosa. Since most of the plasma membrane vesicles have a sealed right-side-out orientation after repeated aqueous two-phase partitioning, the ATP-binding sites of H(+)-ATPases are exposed towards inner side. Leaky vesicles were preloaded with Na(+) sealed for the study of H(+)-ATPase-dependent Na(+) transport. Our data implicate that Na(+) movement across vesicle membranes is highly dependent on H(+)-ATPase activity requiring ATP and Mg(2+) and displays optimum rates of 2.50 microM Na(+) mg(-1) membrane protein min(-1) at pH 6.5 and 25 degrees C. In this study, for the first time, we establish new protocols for the preparation of sealed preloaded right-side-out vesicles for the study of H(+)-ATPase-dependent Na(+) transport. The results demonstrate that the Na(+) content of various types of plasma membrane vesicle can be directly quantified by AAS, and the results measured using AAS method were consistent with those determined by the previous established fluorescence probe method. The method is a convenient system for the study of bidirectional H(+)-ATPase-dependent Na(+) transport with membrane vesicles.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17706940?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sasaki, Kanako</style></author><author><style face="normal" font="default" size="100%">Saito, Takuya</style></author><author><style face="normal" font="default" size="100%">Lämsä, Mari</style></author><author><style face="normal" font="default" size="100%">Oksman-Caldentey, Kirsi-Marja</style></author><author><style face="normal" font="default" size="100%">Suzuki, Masashi</style></author><author><style face="normal" font="default" size="100%">Ohyama, Kiyoshi</style></author><author><style face="normal" font="default" size="100%">Muranaka, Toshiya</style></author><author><style face="normal" font="default" size="100%">Ohara, Kazuaki</style></author><author><style face="normal" font="default" size="100%">Yazaki, Kazufumi</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Plants utilize isoprene emission as a thermotolerance mechanism.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant &amp; cell physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">48</style></volume><pages><style face="normal" font="default" size="100%">1254-62</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Isoprene is a volatile compound emitted from leaves of many plant species in large quantities, which has an impact on atmospheric chemistry due to its massive global emission rate (5 x 10(14) carbon g year(-1)) and its high reactivity with the OH radical, resulting in an increase in the half-life of methane. Isoprene emission is strongly induced by the increase in isoprene synthase activity in plastids at high temperature in the day time, which is regulated at its gene expression level in leaves, while the physiological meaning of isoprene emission for plants has not been clearly demonstrated. In this study, we have functionally overexpressed Populus alba isoprene synthase in Arabidopsis to observe isoprene emission from transgenic plants. A striking difference was observed when both transgenic and wild-type plants were treated with heat at 60 degrees C for 2.5 h, i.e. transformants revealed clear heat tolerance compared with the wild type. High isoprene emission and a decrease in the leaf surface temperature were observed in transgenic plants under heat stress treatment. In contrast, neither strong light nor drought treatments showed an apparent difference. These data suggest that isoprene emission plays a crucial role in a heat protection mechanism in plants.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17711876?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Weber, Richard W</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Pussy Willow. Salix discolor.</style></title><secondary-title><style face="normal" font="default" size="100%">Annals of allergy, asthma &amp; immunology : official publication of the American College of Allergy, Asthma, &amp; Immunology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ann. Allergy Asthma Immunol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">99</style></volume><pages><style face="normal" font="default" size="100%">A4</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17910321?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Mertens, Jan</style></author><author><style face="normal" font="default" size="100%">Van Nevel, Lotte</style></author><author><style face="normal" font="default" size="100%">De Schrijver, An</style></author><author><style face="normal" font="default" size="100%">Piesschaert, Frederic</style></author><author><style face="normal" font="default" size="100%">Oosterbaan, Anne</style></author><author><style face="normal" font="default" size="100%">Tack, Filip M G</style></author><author><style face="normal" font="default" size="100%">Verheyen, Kris</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Tree species effect on the redistribution of soil metals.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">149</style></volume><pages><style face="normal" font="default" size="100%">173-81</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Phytostabilization of metals using trees is often promoted although the influence of different tree species on the mobilization of metals is not yet clear. Soil and biomass were sampled 33 years after planting four tree species (Quercus robur, Fraxinus excelsior, Acer pseudoplatanus, Populus 'Robusta') in a plot experiment on dredged sediment. Poplar took up high amounts of Cd and Zn and this was associated with increased Cd and Zn concentrations in the upper soil layer. The other species contained normal concentrations of Cd, Cu, Cr, Pb and Zn in their tissues. Oak acidified the soil more than the other species and caused a decrease in the concentration of metals in the upper soil layer. The pH under poplar was lower than expected and associated with high carbon concentrations in the top soil. This might be assigned to retardation of the litter decomposition due to elevated Cd and Zn concentrations in the litter.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17360090?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kipiani, N V</style></author><author><style face="normal" font="default" size="100%">Kuchukhidze, Dzh K</style></author><author><style face="normal" font="default" size="100%">Chichua, Z Dzh</style></author><author><style face="normal" font="default" size="100%">Kipiani, V A</style></author><author><style face="normal" font="default" size="100%">Datunashvili, I V</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Application of Populus Nigra preparations at experimental parodontitis].</style></title><secondary-title><style face="normal" font="default" size="100%">Georgian medical news</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Georgian Med News</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Sep</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">35-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Severe oxidative stress, developed under experimental periodontitis is accompanied by disturbances in mitochondrial respiration in tissue cells of gingiva, membrane damage and release of Fe(2+) and Mn(2+), leading to the worsening of inflammation process and gingival tissue necrosis. Reduction of free nitric oxide in gingival tissue appeared to be characteristic for experimental parodontitis: decreases local immunity, antimicrobial resistance, and tissue regeneration, disturbs blood supply and tissue trophism, which forwards important role in deepening of inflammation process and wasting of gingival tissue. Application of preparations derived from black poplar (Populus Nigra) gemma standardizes mitochondrial respiration, reduces presentation of inflammation, and considerably improves EPR-spectrum of gingival tissue. Though the complete normalization is not achieved--hazard of peroxidation still remains, the applied preparations, due to their strong anti- oxidative and anti-inflammatory activities is as an effective and rehabilitative means to tackle gingivitis and peiodontitis.</style></abstract><issue><style face="normal" font="default" size="100%">150</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17984561?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Doty, Sharon L</style></author><author><style face="normal" font="default" size="100%">James, C Andrew</style></author><author><style face="normal" font="default" size="100%">Moore, Allison L</style></author><author><style face="normal" font="default" size="100%">Vajzovic, Azra</style></author><author><style face="normal" font="default" size="100%">Singleton, Glenda L</style></author><author><style face="normal" font="default" size="100%">Ma, Caiping</style></author><author><style face="normal" font="default" size="100%">Khan, Zareen</style></author><author><style face="normal" font="default" size="100%">Xin, Gang</style></author><author><style face="normal" font="default" size="100%">Kang, Jun Won</style></author><author><style face="normal" font="default" size="100%">Park, Jin Young</style></author><author><style face="normal" font="default" size="100%">Meilan, Richard</style></author><author><style face="normal" font="default" size="100%">Strauss, Steven H</style></author><author><style face="normal" font="default" size="100%">Wilkerson, Jasmine</style></author><author><style face="normal" font="default" size="100%">Farin, Federico</style></author><author><style face="normal" font="default" size="100%">Strand, Stuart E</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Enhanced phytoremediation of volatile environmental pollutants with transgenic trees.</style></title><secondary-title><style face="normal" font="default" size="100%">Proceedings of the National Academy of Sciences of the United States of America</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Proc. Natl. Acad. Sci. U.S.A.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Oct 23</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">104</style></volume><pages><style face="normal" font="default" size="100%">16816-21</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Small, volatile hydrocarbons, including trichloroethylene, vinyl chloride, carbon tetrachloride, benzene, and chloroform, are common environmental pollutants that pose serious health effects. We have developed transgenic poplar (Populus tremula x Populus alba) plants with greatly increased rates of metabolism and removal of these pollutants through the overexpression of cytochrome P450 2E1, a key enzyme in the metabolism of a variety of halogenated compounds. The transgenic poplar plants exhibited increased removal rates of these pollutants from hydroponic solution. When the plants were exposed to gaseous trichloroethylene, chloroform, and benzene, they also demonstrated superior removal of the pollutants from the air. In view of their large size and extensive root systems, these transgenic poplars may provide the means to effectively remediate sites contaminated with a variety of pollutants at much faster rates and at lower costs than can be achieved with current conventional techniques.</style></abstract><issue><style face="normal" font="default" size="100%">43</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17940038?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Han, Yuepeng</style></author><author><style face="normal" font="default" size="100%">Sun, Feng-Jie</style></author><author><style face="normal" font="default" size="100%">Rosales-Mendoza, Sergio</style></author><author><style face="normal" font="default" size="100%">Korban, Schuyler S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Three orthologs in rice, Arabidopsis, and Populus encoding starch branching enzymes (SBEs) are different from other SBE gene families in plants.</style></title><secondary-title><style face="normal" font="default" size="100%">Gene</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Gene</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Oct 15</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">401</style></volume><pages><style face="normal" font="default" size="100%">123-30</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Starch branching enzymes (SBEs) play important roles in plant starch synthesis. Three orthologs encoding SBEs in rice, Arabidopsis thaliana, and Populus trichocarpa are described. Putative amino acid sequences of these three SBE genes show approximately 30% identity to those of SBEI and SBEII from plants such as maize, barley, and wheat. More interestingly, they share approximately 31% amino acid sequence identity with those of glycogen-branching enzymes from such animals as mouse, horse, and monkey. The three genes have similar genomic structures, but their structural features are quite different from those of genes of both SBEI and SBEII families in plants. Based on phylogenetic analysis and genomic structure comparison, it is proposed that the three SBE genes represent a new family of SBEs.</style></abstract><issue><style face="normal" font="default" size="100%">1-2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17698298?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zak, Donald R</style></author><author><style face="normal" font="default" size="100%">Holmes, William E</style></author><author><style face="normal" font="default" size="100%">Pregitzer, Kurt S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Atmospheric CO2 and O3 alter the flow of 15N in developing forest ecosystems.</style></title><secondary-title><style face="normal" font="default" size="100%">Ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ecology</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">88</style></volume><pages><style face="normal" font="default" size="100%">2630-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Anthropogenic O3 and CO2-induced declines in soil N availability could counteract greater plant growth in a CO2-enriched atmosphere, thereby reducing net primary productivity (NPP) and the potential of terrestrial ecosystems to sequester anthropogenic CO2. Presently, it is uncertain how increasing atmospheric CO2 and O3 will alter plant N demand and the acquisition of soil N by plants as well as the microbial supply of N from soil organic matter. To address this uncertainty, we initiated an ecosystem-level 15N tracer experiment at the Rhinelander (Wisconsin, USA) free air CO2-O3 enrichment (FACE) facility to understand how projected increases in atmospheric CO2 and 03 alter the distribution and flow of N in developing northern temperate forests. Tracer amounts of 15NH4+ were applied to the forest floor of developing Populus tremuloides and P. tremuloides-Betula papyrifera communities that have been exposed to factorial CO2 and O3 treatments for seven years. One year after isotope addition, both forest communities exposed to elevated CO2 obtained greater amounts of 15N (29%) and N (40%) from soil, despite no change in soil N availability or plant N-use efficiency. As such, elevated CO2 increased the ability of plants to exploit soil for N, through the development of a larger root system. Conversely, elevated O3 decreased the amount of 15N (-15%) and N (-29%) in both communities, a response resulting from lower rates of photosynthesis, decreases in growth, and smaller root systems that acquired less soil N. Neither CO2 nor 03 altered the amount of N or 15N recovery in the forest floor, microbial biomass, or soil organic matter. Moreover, we observed no interaction between CO2 and 03 on the amount of N or 15N in any ecosystem pool, suggesting that 03 could exert a negative effect regardless of CO2 concentration. In a CO2-enriched atmosphere, greater belowground growth and a more thorough exploitation of soil for growth-limiting N is an important mechanism sustaining the enhancement of NPP in developing forests (0-8 years following establishment). However, as CO2 accumulates in the Earth's atmosphere, future O3 concentrations threaten to diminish the enhancement of plant growth, decrease plant N acquisition, and lessen the storage of anthropogenic C in temperate forests.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18027765?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Tenczar, Emily G</style></author><author><style face="normal" font="default" size="100%">Krischik, Vera A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Comparison of standard (granular and drench) and novel (tablet, stick soak, and root dip) imidacloprid treatments for cottonwood leaf beetle (Coleoptera: Chrysomelidae) management on hybrid poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of economic entomology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Econ. Entomol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">100</style></volume><pages><style face="normal" font="default" size="100%">1611-21</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Standard soil application methods (granular and drench) were compared with novel methods (tablet, stick soak, and root dip) for efficacy and duration in hybrid poplar (Populus spp.) against adult and larval cottonwood leaf beetle, Chrysomela scripta F. (Coleoptera: Chrysomelidae). Beetle feeding can kill saplings and significantly damage trees by reducing tree height, diameter, and biomass. Tablets offer lower risk to applicators and beneficial insects, because insecticides do not need to be measured and sprayed. In field- and container-grown plants, standard granular and drench application methods had similar efficacy and duration compared with tablets. In field-grown plants, adult and larval survivorship was reduced for 12 mo with the two highest rates of tablet (0.25 x and 0.5 x) treatments, and in container-grown plants, with all rates of tablet (0.25 x, 0.5 x, and 1 x ) treatments that were used. Two other novel application methods, stick soak and root dip, offer new methods for protecting vulnerable transplants in nursery propagation. In container-grown plants, adult survivorship was reduced for 8 mo and larval survivorship for 12 mo for all rates of stick soak (0.5 x, 1 x, and 2 x) and all rates of root dip (1 x, 2 x, and 4 x) treatments. Literature searches revealed little data on the efficacy and duration of soil-applied imidacloprid for trees, even though it is the primary insecticide used for defoliators and some borers in landscape and in nurseries for field and container production.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17972639?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">García, M V</style></author><author><style face="normal" font="default" size="100%">Ingvarsson, P K</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">An excess of nonsynonymous polymorphism and extensive haplotype structure at the PtABI1B locus in European aspen (Populus tremula): a case of balancing selection in an obligately outcrossing plant?</style></title><secondary-title><style face="normal" font="default" size="100%">Heredity</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Heredity (Edinb)</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">99</style></volume><pages><style face="normal" font="default" size="100%">381-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Here, we describe an unusually pronounced haplotype structure at the PtABI1B locus in the obligately outcrossing tree Populus tremula. Both nucleotide diversity and divergence at PtABI1B was low compared to other P. tremula genes suggesting that the gene is located in a region with a low mutation rate. Despite this, PtABI1B shows a very marked excess of nonsynonymous polymorphisms across the entire coding region and linkage disequilibrium (LD) extending across the entire PtABI1B region of approximately 2.6 kb. Such extensive LD is normally not seen in P. tremula. The extensive LD at PtABI1B is caused by the presence of two distinct haplotypes. The haplotype structure is not caused by a lack of recombination in the region, because evidence of recombination can be detected. In addition, several statistical tests strongly reject neutrality for the PtABI1B region, suggesting that the unusual haplotype structure could be actively maintained by balancing selection.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17551523?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Li, ShuXian</style></author><author><style face="normal" font="default" size="100%">Yin, Tongming</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Map and analysis of microsatellites in the genome of Populus: the first sequenced perennial plant.</style></title><secondary-title><style face="normal" font="default" size="100%">Science in China. Series C, Life sciences / Chinese Academy of Sciences</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Sci. China, C, Life Sci.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">50</style></volume><pages><style face="normal" font="default" size="100%">690-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We mapped and analyzed the microsatellites throughout 284295605 base pairs of the unambiguously assembled sequence scaffolds along 19 chromosomes of the haploid poplar genome. Totally, we found 150985 SSRs with repeat unit lengths between 2 and 5 bp. The established microsatellite physical map demonstrated that SSRs were distributed relatively evenly across the genome of Populus. On average, These SSRs occurred every 1883 bp within the poplar genome and the SSR densities in intergenic regions, introns, exons and UTRs were 85.4%, 10.7%, 2.7% and 1.2%, respectively. We took di-, tri-, tetra-and pentamers as the four classes of repeat units and found that the density of each class of SSRs decreased with the repeat unit lengths except for the tetranucleotide repeats. It was noteworthy that the length diversification of microsatellite sequences was negatively correlated with their repeat unit length and the SSRs with shorter repeat units gained repeats faster than the SSRs with longer repeat units. We also found that the GC content of poplar sequence significantly correlated with densities of SSRs with uneven repeat unit lengths (tri-and penta-), but had no significant correlation with densities of SSRs with even repeat unit lengths (di-and tetra-). In poplar genome, there were evidences that the occurrence of different microsatellites was under selection and the GC content in SSR sequences was found to significantly relate to the functional importance of microsatellites.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17879069?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ouyang, Ying</style></author><author><style face="normal" font="default" size="100%">Huang, Cheng He</style></author><author><style face="normal" font="default" size="100%">Huang, Dong Yi</style></author><author><style face="normal" font="default" size="100%">Lin, Dian</style></author><author><style face="normal" font="default" size="100%">Cui, Lihua</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Simulating uptake and transport of TNT by plants using STELLA.</style></title><secondary-title><style face="normal" font="default" size="100%">Chemosphere</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Chemosphere</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">69</style></volume><pages><style face="normal" font="default" size="100%">1245-52</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Understanding the uptake and transport of soil organic contaminants by plants is crucial to a successful application of phytoremediation technique. This study investigated the removal of 2,4,6-trinitrotoluene (TNT) from a contaminated sandy soil by a poplar tree (Populus fastigiata) through the examinations of temporal variations of xylem water potential, leaf water transpiration, and root water and TNT uptake. A dynamic model for Uptake and Translocation of Contaminants from a Soil-Plant ecosystem (UTCSP), developed using the STELLA software package, was modified for the purpose of this study. The model was calibrated using laboratory measurements prior to its application. Simulation results showed that about 25% of TNT was removed from the soil by the poplar tree in 90 days. Simulations further revealed that the rates of water and TNT up taken by roots had a typical diurnal variation pattern: increasing during the day and decreasing during the night, resulting from daily variations of xylem water potentials that were caused by leaf water transpiration. In general, the storage of TNT mass in the roots decreased with time and occurred partially because of the low availability of soil TNT as time elapsed and partially because of the biodegradation of TNT in the plant tissues. This study suggests that the UTCSP model could be a useful tool for estimating phytoremediation of soil TNT by a plant.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17655913?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gould, Georgianna G</style></author><author><style face="normal" font="default" size="100%">Jones, Clive G</style></author><author><style face="normal" font="default" size="100%">Rifleman, Peggy</style></author><author><style face="normal" font="default" size="100%">Perez, Antonio</style></author><author><style face="normal" font="default" size="100%">Coleman, James S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Variation in Eastern cottonwood (Populus deltoides Bartr.) phloem sap content caused by leaf development may affect feeding site selection behavior of the aphid, Chaitophorous populicola Thomas (Homoptera: Aphididae).</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental entomology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Entomol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">36</style></volume><pages><style face="normal" font="default" size="100%">1212-25</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Apterous populations of Chaitophorous populicola Thomas (Homoptera: Aphididae) appear to track Eastern cottonwood (Populus deltoides Bartr.) leaf development. Few aphids occur on mature leaves. Marked individual aphids on leaves of different developmental stages were observed through a period of new leaf initiation. Nymph and adult C. populicola frequently track leaf development by moving up to younger leaves. A comparison of phloem sap constituents and leaf toughness among leaf developmental stages revealed some differences that could be used by C. populicola to determine leaf age. Phloem sap exudates, collected from P. deltoides leaves of different developmental stages, were analyzed by high-performance liquid chromatography for free amino acids and the phenolic glycoside salicin. Sucrose concentration in exudates, indicative of phloem sap exudation rate, was uniform among leaf stages. Of 20 amino acids examined, only aspartic acid and gamma-amino-n-butyric acid (GABA) concentrations differed significantly between leaf stages. Forward stepwise discriminant function analysis showed that seven of the amino acids analyzed are useful for classifying leaf maturity groupings. Aphid-infested cottonwoods had lower cystine concentrations in phloem sap than aphid-free plants. Salicin concentration was significantly higher in new leaves. Leaf toughness was assessed by lignin density and distance measurements in petiole cross-sections. Rapidly expanding leaves had significantly less lignification and new leaves had shorter distances to the vascular bundles than senescent leaves. These physiological and phytochemical differences among P. deltoides leaf developmental stages may contribute to the leaf stage selection patterns exhibited by the aphid, C. populicola.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18284747?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rüth, Björn</style></author><author><style face="normal" font="default" size="100%">Lennartz, Bernd</style></author><author><style face="normal" font="default" size="100%">Kahle, Petra</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Water regime of mechanical-biological pretreated waste materials under fast-growing trees.</style></title><secondary-title><style face="normal" font="default" size="100%">Waste management &amp; research : the journal of the International Solid Wastes and Public Cleansing Association, ISWA</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Waste Manag Res</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">25</style></volume><pages><style face="normal" font="default" size="100%">408-16</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In this study mechanical-biological pre-treated waste material (MBP) was tested for suitability to serve as an alternative surface layer in combination with fast-growing and water-consumptive trees for final covers at landfill sites. The aim was to quantify evapotranspiration and seepage losses by numerical model simulations for two sites in Germany. In addition, the leaf area index (LAI) of six tree species over the growing season as the driving parameter for transpiration calculations was determined experimentally. The maximum LAI varied between 3.8 and 6.1 m2 m(-2) for poplar and willow clones, respectively. The evapotranspiration calculations revealed that the use of MBP waste material for re-cultivation enhanced evapotranspiration by 40 mm year(-1) (10%) over an 11 year calculation period compared to a standard mineral soil. Between 82% (for LAI(max) = 3.8) and 87% (for LAI(max) = 6.1) of the average annual precipitation (506 mm) could be retained from the surface layer assuming eastern German climate conditions, compared with a retention efficiency between 79 and 82% for a mineral soil. Although a MBP layer in conjunction with water-consumptive trees can reduce vertical water losses as compared to mineral substrates, the effect is not sufficient to meet legal regulations.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17985666?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Yang, Li-Pan</style></author><author><style face="normal" font="default" size="100%">Liu, Wen-Yao</style></author><author><style face="normal" font="default" size="100%">Yang, Guo-Ping</style></author><author><style face="normal" font="default" size="100%">Ma, Wen-Zhang</style></author><author><style face="normal" font="default" size="100%">Li, Da-Wen</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Composition and carbon storage of woody debris in moist evergreen broad-leaved forest and its secondary forests in Ailao Mountains of Yunnan Provinve].</style></title><secondary-title><style face="normal" font="default" size="100%">Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ying Yong Sheng Tai Xue Bao</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">18</style></volume><pages><style face="normal" font="default" size="100%">2153-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">This paper studied the composition and carbon storage of woody debris in the primary moist evergreen broad-leaved forest and its main secondary forests (regenerated Lithocarpus forest, Populus bonatii forest, and Alnus nepalensis forest) in Ailao Moutains of Yunnan Province. The results showed that in the primary forest, the carbon storage of woody debris amounted to 36.56 t x hm(-2). Castanopsis wattii, Lithocarpus xylocarpus and L. chintungensis were the main contributors, and most of them were the logs with larger diameter and at intermediate stage of decay. The unique environment of richer precipitation, higher humidity and lower temperature in the study area, and the decay-resistance of hardwood were favorable to the accumulation of woody debris. The three secondary forests had a carbon storage of 1.2-5.0 t x hm(-2), which decreased in the order of regenerated Lithocaropus forest &gt; P. bonatii forest &gt; A. nepalensis forest, showing a tendency of increasing carbon storage with succession course.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18163291?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Han, Hui-Jing</style></author><author><style face="normal" font="default" size="100%">Zhang, Fa-Yong</style></author><author><style face="normal" font="default" size="100%">Yang, Min-Sheng</style></author><author><style face="normal" font="default" size="100%">Liang, Hai-Yong</style></author><author><style face="normal" font="default" size="100%">Zhang, Hua-Xin</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Effects of NaCl stress on the exogenous gene expression in transgenic poplar plants].</style></title><secondary-title><style face="normal" font="default" size="100%">Zhi wu sheng li yu fen zi sheng wu xue xue bao = Journal of plant physiology and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Zhi Wu Sheng Li Yu Fen Zi Sheng Wu Xue Xue Bao</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">33</style></volume><pages><style face="normal" font="default" size="100%">435-40</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The expressions of BtCry1Ac insect-resistance genes and rhizogenesis genes and their response to NaCl stress were studied using tissue culture plants of high transgenic insect-resistant 'poplar 741' and transpolygenes 741 (insect-resistant genes and T-DNA of Ri plasmid). The results showed that IAA and GA contents increased quickly, plant root number increased and root length reduced after rhizogenesis and hormone synthesis related gene in Ri T-DNA were inserted into the genome of poplar (Figs.2, 3, 8 and 9). Plant height, root number, chlorophyll content, IAA and GA contents decreased gradually with an increase in NaCl stress intensity (Figs.1, 2, 4-6, 8 and 9). Apiece index change extent of transgenic rol gene plant was smaller than transgenic Bt gene plant and non-transgenic plant. Bt toxin protein content of transgenic rol gene plant increased significantly under NaCl stress (Fig.7). Our results indicate that the expressions of the foreign genes changed with the changes of the environmental conditions.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17960047?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zalesny, Jill A</style></author><author><style face="normal" font="default" size="100%">Zalesny, Ronald S</style></author><author><style face="normal" font="default" size="100%">Wiese, Adam H</style></author><author><style face="normal" font="default" size="100%">Hall, Richard B</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Choosing tree genotypes for phytoremediation of landfill leachate using phyto-recurrent selection.</style></title><secondary-title><style face="normal" font="default" size="100%">International journal of phytoremediation</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Int J Phytoremediation</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Nov-Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">513-30</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Information about the response of poplar (Populus spp.) genotypes to landfill leachate irrigation is needed, along with efficient methods for choosing genotypes based on leachate composition. Poplar clones were irrigated during three cycles of phyto-recurrent selection to test whether genotypes responded differently to leachate and water, and to test whether the methodology had merit as a tool for plant selection during remediation. Fifteen below- and above-ground traits were evaluated. Twenty-five clones were tested in cycle 1, while the best l2 genotypes were evaluated in cycles 2 and 3. Eight clones were selected and subsequently tested in an in situ landfill study (cycle 4). Results from cycles 1, 2, and 3 are presented here. Overall, clones responded differently to irrigation treatments, with certain genotypes exhibiting better below- and above-ground growth with water than leachate. However, growth was greater with leachate irrigation for some clones. In addition, differences between treatments within clones decreased with days after planting (DAP). There were no treatment differences for number of leaves, height, and root length at the end of cycle 2 (45 DAP) or cycle 3 (30 DAP). These results detail the extensive variation in clonal responses to leachate irrigation, along with the need and efficacy of using phyto-recurrent selection to choose superior genotypes.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18246777?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zalesny, Ronald S</style></author><author><style face="normal" font="default" size="100%">Bauer, Edmund O</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Selecting and utilizing Populus and Salix for landfill covers: implications for leachate irrigation.</style></title><secondary-title><style face="normal" font="default" size="100%">International journal of phytoremediation</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Int J Phytoremediation</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Nov-Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">497-511</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The success of using Populus and Salix for phytoremediation has prompted further use of leachate as a combination of irrigation and fertilization for the trees. A common protocol for such efforts has been to utilize a limited number of readily-available genotypes with decades of deployment in other applications, such as fiber or windbreaks. However, it may be possible to increase phytoremediation success with proper genotypic screening and selection, followed by the field establishment of clones that exhibited favorable potential for cleanup of specific contaminants. There is an overwhelming need for testing and subsequent deployment of diverse Populus and Salix genotypes, given current availability of clonal material and the inherent genetic variation among and within these genera. Therefore, we detail phyto-recurrent selection, a method that consists of revising and combining crop and tree improvement protocols to meet the objective of utilizing superior Populus and Salix clones for remediation applications. Although such information is lacking for environmental clean-up technologies, centuries of plant selection success in agronomy, horticulture, and forestry validate the need for similar approaches in phytoremediation. We bridge the gap between these disciplines by describing project development, clone selection, tree establishment, and evaluation of success metrics in the context of their importance to utilizing trees for phytoremediation.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18246776?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hartonen, Kari</style></author><author><style face="normal" font="default" size="100%">Parshintsev, Jevgeni</style></author><author><style face="normal" font="default" size="100%">Sandberg, Kati</style></author><author><style face="normal" font="default" size="100%">Bergelin, Eija</style></author><author><style face="normal" font="default" size="100%">Nisula, Linda</style></author><author><style face="normal" font="default" size="100%">Riekkola, Marja-Liisa</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Isolation of flavonoids from aspen knotwood by pressurized hot water extraction and comparison with other extraction techniques.</style></title><secondary-title><style face="normal" font="default" size="100%">Talanta</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Talanta</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Nov 15</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">74</style></volume><pages><style face="normal" font="default" size="100%">32-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Pressurized hot water extraction (PHWE) conditions (time, temperature, pressure) were optimized for the extraction of naringenin and other major flavonoids (dihydrokaempferol, naringin) from knotwood of aspen. Extracts were analysed by GC-FID, GC-MS, HPLC-UV and HPLC-MS. The results were compared with those obtained by Soxhlet, ultrasonic extraction and reflux in methanol. Flavonoids were most efficiently extracted with PHWE at 150 degrees C and 220 bar with 35 min extraction time. Soxhlet with methanol gave slightly higher recoveries, but an extraction time of 48 h was required. Naringenin concentration was highest in knotwood (1.15% dry weight) and much lower in the sapwood. PHWE proved to be cheap, fast and effective for the isolation of biofunctional flavonoids from aspen knotwood, producing higher recoveries than 24 h Soxhlet extraction, sonication or 24 h reflux.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18371609?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ueda, Minoru</style></author><author><style face="normal" font="default" size="100%">Fujimoto, Masaru</style></author><author><style face="normal" font="default" size="100%">Arimura, Shin-ichi</style></author><author><style face="normal" font="default" size="100%">Murata, Jin</style></author><author><style face="normal" font="default" size="100%">Tsutsumi, Nobuhiro</style></author><author><style face="normal" font="default" size="100%">Kadowaki, Koh-ichi</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Loss of the rpl32 gene from the chloroplast genome and subsequent acquisition of a preexisting transit peptide within the nuclear gene in Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">Gene</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Gene</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Nov 1</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">402</style></volume><pages><style face="normal" font="default" size="100%">51-6</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Gene transfer events from organelle genomes (mitochondria and chloroplasts in plants) to the nuclear genome are important processes in the evolution of the eukaryotic cell. It is highly likely that the gene transfer event is still an ongoing process in higher plant mitochondria and chloroplasts. The number and order of genes encoded in the chloroplast genome of higher plants are highly conserved. Recently, several exceptional cases of gene loss from the chloroplast genome have been discovered as the number of complete chloroplast genome sequences has increased. The Populus chloroplast genome has lost the rpl32 gene, while the corresponding the chloroplast rpl32 (cp rpl32) gene has been identified in the nuclear genome. Nuclear genes transferred from the chloroplast genome need to gain a sequence that encodes a transit peptide. Here, we revealed that the nuclear cp rpl32 gene has acquired the exon sequence, which is highly homologous to a transit peptide derived from the chloroplast Cu-Zn superoxide dismutase (cp sod-1) gene. The cp rpl32 gene has acquired the sequence that encodes not only for the transit peptide, but also for the conserved N-terminal portion of the mature SOD protein from the cp sod-1 gene, suggesting the occurrence of DNA sequence duplication. Unlike cp SOD-1, cp RPL32 did not show biased localization in the chloroplasts. This difference may be caused by mutations accumulated in the sequence of the SOD domain on the cp rpl32 gene. We provide new insight into the fate of the inherent sequence derived from a transit peptide.</style></abstract><issue><style face="normal" font="default" size="100%">1-2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17728076?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Björklund, Simon</style></author><author><style face="normal" font="default" size="100%">Antti, Henrik</style></author><author><style face="normal" font="default" size="100%">Uddestrand, Ida</style></author><author><style face="normal" font="default" size="100%">Moritz, Thomas</style></author><author><style face="normal" font="default" size="100%">Sundberg, Björn</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Cross-talk between gibberellin and auxin in development of Populus wood: gibberellin stimulates polar auxin transport and has a common transcriptome with auxin.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">52</style></volume><pages><style face="normal" font="default" size="100%">499-511</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Both indole acetic acid (IAA) and gibberellins (GAs) stimulate cell and organ growth. We have examined GA/IAA cross-talk in cambial growth of hybrid aspen (Populus tremulaxtremuloides). Decapitated trees were fed with IAA and GA, alone and in combination. Endogenous hormone levels after feeding were measured, by mass spectrometry, in the stem tissues below the point of application. These stem tissues with defined hormone balances were also used for global transcriptome analysis, and the abundance of selected transcripts was measured by real-time reverse-transcription polymerase chain reaction. By feeding isotope-labeled IAA, we demonstrated that GA increases auxin levels in the stem by stimulating polar auxin transport. This finding adds a new dimension to the concept that the endogenous GA/IAA balance in plants is determined by cross-talk between the two hormones. We also show that GA has a common transcriptome with auxin, including many transcripts related to cell growth. This finding provides molecular support to physiological experiments demonstrating that either hormone can induce growth if the other hormone is absent/deficient because of mutations or experimental treatments. It also highlights the potential for extensive cross-talk between GA- and auxin-induced responses in vegetative growth of the intact plant. The role of endogenous IAA and GA in wood development is discussed.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17825053?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Oakley, Rodney V</style></author><author><style face="normal" font="default" size="100%">Wang, Yuh-Shuh</style></author><author><style face="normal" font="default" size="100%">Ramakrishna, Wusirika</style></author><author><style face="normal" font="default" size="100%">Harding, Scott A</style></author><author><style face="normal" font="default" size="100%">Tsai, Chung-Jui</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Differential expansion and expression of alpha- and beta-tubulin gene families in Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">145</style></volume><pages><style face="normal" font="default" size="100%">961-73</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Microtubule organization is intimately associated with cellulose microfibril deposition, central to plant secondary cell wall development. We have determined that a relatively large suite of eight alpha-TUBULIN (TUA) and 20 beta-TUBULIN (TUB) genes is expressed in the woody perennial Populus. A number of features, including gene number, alpha:beta gene representation, amino acid changes at the C terminus, and transcript abundance in wood-forming tissue, distinguish the Populus tubulin suite from that of Arabidopsis thaliana. Five of the eight Populus TUAs are unusual in that they contain a C-terminal methionine, glutamic acid, or glutamine, instead of the more typical, and potentially regulatory, C-terminal tyrosine. Both C-terminal Y-type (TUA1) and M-type (TUA5) TUAs were highly expressed in wood-forming tissues and pollen, while the Y-type TUA6 and TUA8 were abundant only in pollen. Transcripts of the disproportionately expanded TUB family were present at comparatively low levels, with phylogenetically distinct classes predominating in xylem and pollen. When tension wood induction was used as a model system to examine changes in tubulin gene expression under conditions of augmented cellulose deposition, xylem-abundant TUA and TUB genes were up-regulated. Immunolocalization of TUA and TUB in xylem and phloem fibers of stems further supported the notion of heavy microtubule involvement during cellulose microfibril deposition in secondary walls. The high degree of sequence diversity, differential expansion, and differential regulation of Populus TUA and TUB families may confer flexibility in cell wall formation that is of adaptive significance to the woody perennial growth habit.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17885081?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Leplé, Jean-Charles</style></author><author><style face="normal" font="default" size="100%">Dauwe, Rebecca</style></author><author><style face="normal" font="default" size="100%">Morreel, Kris</style></author><author><style face="normal" font="default" size="100%">Storme, Véronique</style></author><author><style face="normal" font="default" size="100%">Lapierre, Catherine</style></author><author><style face="normal" font="default" size="100%">Pollet, Brigitte</style></author><author><style face="normal" font="default" size="100%">Naumann, Annette</style></author><author><style face="normal" font="default" size="100%">Kang, Kyu-Young</style></author><author><style face="normal" font="default" size="100%">Kim, Hoon</style></author><author><style face="normal" font="default" size="100%">Ruel, Katia</style></author><author><style face="normal" font="default" size="100%">Lefèbvre, Andrée</style></author><author><style face="normal" font="default" size="100%">Joseleau, Jean-Paul</style></author><author><style face="normal" font="default" size="100%">Grima-Pettenati, Jacqueline</style></author><author><style face="normal" font="default" size="100%">De Rycke, Riet</style></author><author><style face="normal" font="default" size="100%">Andersson-Gunnerås, Sara</style></author><author><style face="normal" font="default" size="100%">Erban, Alexander</style></author><author><style face="normal" font="default" size="100%">Fehrle, Ines</style></author><author><style face="normal" font="default" size="100%">Petit-Conil, Michel</style></author><author><style face="normal" font="default" size="100%">Kopka, Joachim</style></author><author><style face="normal" font="default" size="100%">Polle, Andrea</style></author><author><style face="normal" font="default" size="100%">Messens, Eric</style></author><author><style face="normal" font="default" size="100%">Sundberg, Björn</style></author><author><style face="normal" font="default" size="100%">Mansfield, Shawn D</style></author><author><style face="normal" font="default" size="100%">Ralph, John</style></author><author><style face="normal" font="default" size="100%">Pilate, Gilles</style></author><author><style face="normal" font="default" size="100%">Boerjan, Wout</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Downregulation of cinnamoyl-coenzyme A reductase in poplar: multiple-level phenotyping reveals effects on cell wall polymer metabolism and structure.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant cell</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">19</style></volume><pages><style face="normal" font="default" size="100%">3669-91</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Cinnamoyl-CoA reductase (CCR) catalyzes the penultimate step in monolignol biosynthesis. We show that downregulation of CCR in transgenic poplar (Populus tremula x Populus alba) was associated with up to 50% reduced lignin content and an orange-brown, often patchy, coloration of the outer xylem. Thioacidolysis, nuclear magnetic resonance (NMR), immunocytochemistry of lignin epitopes, and oligolignol profiling indicated that lignin was relatively more reduced in syringyl than in guaiacyl units. The cohesion of the walls was affected, particularly at sites that are generally richer in syringyl units in wild-type poplar. Ferulic acid was incorporated into the lignin via ether bonds, as evidenced independently by thioacidolysis and by NMR. A synthetic lignin incorporating ferulic acid had a red-brown coloration, suggesting that the xylem coloration was due to the presence of ferulic acid during lignification. Elevated ferulic acid levels were also observed in the form of esters. Transcript and metabolite profiling were used as comprehensive phenotyping tools to investigate how CCR downregulation impacted metabolism and the biosynthesis of other cell wall polymers. Both methods suggested reduced biosynthesis and increased breakdown or remodeling of noncellulosic cell wall polymers, which was further supported by Fourier transform infrared spectroscopy and wet chemistry analysis. The reduced levels of lignin and hemicellulose were associated with an increased proportion of cellulose. Furthermore, the transcript and metabolite profiling data pointed toward a stress response induced by the altered cell wall structure. Finally, chemical pulping of wood derived from 5-year-old, field-grown transgenic lines revealed improved pulping characteristics, but growth was affected in all transgenic lines tested.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18024569?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Raffaele, Sylvain</style></author><author><style face="normal" font="default" size="100%">Mongrand, Sébastien</style></author><author><style face="normal" font="default" size="100%">Gamas, Pascal</style></author><author><style face="normal" font="default" size="100%">Niebel, Andreas</style></author><author><style face="normal" font="default" size="100%">Ott, Thomas</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genome-wide annotation of remorins, a plant-specific protein family: evolutionary and functional perspectives.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">145</style></volume><pages><style face="normal" font="default" size="100%">593-600</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17984200?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Dijkstra, Feike A</style></author><author><style face="normal" font="default" size="100%">Cheng, Weixin</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Interactions between soil and tree roots accelerate long-term soil carbon decomposition.</style></title><secondary-title><style face="normal" font="default" size="100%">Ecology letters</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ecol. Lett.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">10</style></volume><pages><style face="normal" font="default" size="100%">1046-53</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Decomposition of soil organic carbon (SOC) is the main process governing the release of CO(2) into the atmosphere from terrestrial systems. Although the importance of soil-root interactions for SOC decomposition has increasingly been recognized, their long-term effect on SOC decomposition remains poorly understood. Here we provide experimental evidence for a rhizosphere priming effect, in which interactions between soil and tree roots substantially accelerate SOC decomposition. In a 395-day greenhouse study with Ponderosa pine and Fremont cottonwood trees grown in three different soils, SOC decomposition in the planted treatments was significantly greater (up to 225%) than in soil incubations alone. This rhizosphere priming effect persisted throughout the experiment, until well after initial soil disturbance, and increased with a greater amount of root-derived SOC formed during the experiment. Loss of old SOC was greater than the formation of new C, suggesting that increased C inputs from roots could result in net soil C loss.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17910623?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hermle, Sandra</style></author><author><style face="normal" font="default" size="100%">Vollenweider, Pierre</style></author><author><style face="normal" font="default" size="100%">Günthardt-Goerg, Madeleine S</style></author><author><style face="normal" font="default" size="100%">McQuattie, Carolyn J</style></author><author><style face="normal" font="default" size="100%">Matyssek, Rainer</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Leaf responsiveness of Populus tremula and Salix viminalis to soil contaminated with heavy metals and acidic rainwater.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">27</style></volume><pages><style face="normal" font="default" size="100%">1517-31</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Fast-growing trees such as Salix viminalis L. and Populus tremula L. are well suited to phytoremediate heavy metal contaminated soils. However, information on tree performance, particularly leaf function, under conditions of heavy metal contamination is scarce. We used yearly coppiced saplings of S. viminalis and P. tremula growing in model ecosytems to test four hypotheses: (1) heavy metal contamination impairs photosynthesis by injuring leaf structure; (2) the effects of heavy metal contamination are enhanced by acidified rainwater and low soil pH; (3) heavy metal contamination increases dark respiration and, thus, repair processes; and (4) heavy metal contamination is tolerated and remediated better by S. viminalis than by P. tremula. We investigated heavy metal accumulation, tissue injury and gas exchange in leaves of plants subjected to controlled soil contamination with heavy metal dust. Additional treatments included acidic and calcareous natural forest subsoils in combination with irrigation with rainwater at pH 5.5 or 3.5. In both provenances of P. tremula that were studied, but not in S. viminalis, heavy metal treatment reduced photosynthesis and transpiration by varying amounts, except in the hot and dry summer of 2003, but had no effect on dark respiration. At light saturation, net CO(2) uptake and water-use efficiency were reduced by heavy metal contamination, whereas the CO(2) concentration in the leaf intercellular air space was increased. Rainwater pH and subsoil pH only slightly modified the effects of the heavy metal treatment on P. tremula. Gas exchange responses of P. tremula to heavy metals were attributed to leaf structural and ultrastructural changes resulting from hypersensitive-response-like processes and accelerated mesophyll cell senescence and necroses in the lower epidermis, especially along the transport pathways of heavy metals in the leaf lamina. Overall, the effects of heavy metals on P. tremula corroborated Hypothesis 1, but refuted Hypotheses 2 and 3, and were inconclusive for Hypothesis 4. Both P. tremula and S. viminalis showed appreciable potential for storing heavy metals in aging foliage.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17669741?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Li, Jiebing</style></author><author><style face="normal" font="default" size="100%">Henriksson, Gunnar</style></author><author><style face="normal" font="default" size="100%">Gellerstedt, Göran</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Lignin depolymerization/repolymerization and its critical role for delignification of aspen wood by steam explosion.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioresource technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bioresour. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">98</style></volume><pages><style face="normal" font="default" size="100%">3061-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Steam explosion is an important process for the fractionation of biomass components. In order to understand the behaviour of lignin under the conditions encountered in the steam explosion process, as well as in other types of steam treatment, aspen wood and isolated lignin from aspen were subjected to steam treatment under various conditions. The lignin portion was analyzed using NMR and size exclusion chromatography as major analytical techniques. Thereby, the competition between lignin depolymerization and repolymerization was revealed and the conditions required for these two types of reaction identified. Addition of a reactive phenol, 2-naphthol, was shown to inhibit the repolymerization reaction strongly, resulting in a highly improved delignification by subsequent solvent extraction and an extracted lignin of uniform structure.</style></abstract><issue><style face="normal" font="default" size="100%">16</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17141499?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Barbehenn, Raymond V</style></author><author><style face="normal" font="default" size="100%">Jones, Christopher P</style></author><author><style face="normal" font="default" size="100%">Yip, Lynn</style></author><author><style face="normal" font="default" size="100%">Tran, Lan</style></author><author><style face="normal" font="default" size="100%">Constabel, C Peter</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Limited impact of elevated levels of polyphenol oxidase on tree-feeding caterpillars: assessing individual plant defenses with transgenic poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Oecologia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Oecologia</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">154</style></volume><pages><style face="normal" font="default" size="100%">129-40</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Polyphenol oxidase (PPO) is commonly believed to function as an effective antiherbivore defense in plants. PPO is induced in plants following herbivory, and insect performance is often negatively correlated with PPO levels. However, induced defenses create numerous changes in plants, and very little work has been done to test the direct effects of PPO on insect herbivores separately from other changes. This study examined the impacts of high levels of PPO on the performance of two species of tree-feeding caterpillars (Lymantria dispar and Orgyia leucostigma) on poplar. Transgenic PPO-overexpressing poplar (Populus tremula x Populus alba) was used as a source of elevated-PPO leaves, thereby controlling for the multiple effects of induction. In addition, the impacts of treating poplar foliage with high levels of purified mushroom PPO were examined on the two caterpillar species. Contrary to expectation, in several cases increased PPO levels had no significant effect on insect consumption or growth rates. Although one of the mechanisms by which PPO is believed to impact herbivores is via increased oxidative stress, the ingestion of large amounts of PPO had little or no effect on semiquinone radical and oxidized protein levels in the gut contents of lymantriid caterpillars. PPO activity in caterpillars is likely limited by the low oxygen and high ascorbate levels commonly found in their gut contents. This study questions whether induced PPO functions as an effective post-ingestive defense against tree-feeding caterpillars, and indicates that controlled, mechanistic studies are needed in other plant-herbivore systems to test for a direct effect of PPO on insect performance.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17724619?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Robinson, B H</style></author><author><style face="normal" font="default" size="100%">Green, S R</style></author><author><style face="normal" font="default" size="100%">Chancerel, B</style></author><author><style face="normal" font="default" size="100%">Mills, T M</style></author><author><style face="normal" font="default" size="100%">Clothier, B E</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Poplar for the phytomanagement of boron contaminated sites.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">150</style></volume><pages><style face="normal" font="default" size="100%">225-33</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Boron (B) is a widespread environmental contaminant that is mobile relative to other trace elements. We investigated the potential of hybrid poplar (Populus sp.) for B phytomanagement using a lysimeter experiment and a field trial on B-contaminated wood-waste. In both studies, poplars enhanced evapotranspiration from the wood-waste, reduced B leaching, and accumulated B in the aerial portions of the tree. When grown in a substrate containing 30 mg/kg B, poplar leaves had an average B concentration of 845 mg/kg, while the stems contained 21 mg/kg B. Leaf B concentrations increased linearly with leaf age. A decomposition experiment revealed that abscised leaves released 14% of their B during the winter months. Fertiliser application enhanced tree growth without decreasing the leaf B concentrations. Harvesting alternate rows of trees on a contaminated site would reduce leaching from the site while removing B. Harvested plant material may provide bioenergy, stock fodder, or an amendment for B-deficient soils.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17382438?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhu, Qi-Hui</style></author><author><style face="normal" font="default" size="100%">Guo, An-Yuan</style></author><author><style face="normal" font="default" size="100%">Gao, Ge</style></author><author><style face="normal" font="default" size="100%">Zhong, Ying-Fu</style></author><author><style face="normal" font="default" size="100%">Xu, Meng</style></author><author><style face="normal" font="default" size="100%">Huang, Minren</style></author><author><style face="normal" font="default" size="100%">Luo, Jinchu</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">DPTF: a database of poplar transcription factors.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioinformatics (Oxford, England)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bioinformatics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 May 15</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">23</style></volume><pages><style face="normal" font="default" size="100%">1307-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The database of poplar transcription factors (DPTF) is a plant transcription factor (TF) database containing 2576 putative poplar TFs distributed in 64 families. These TFs were identified from both computational prediction and manual curation. We have provided extensive annotations including sequence features, functional domains, GO assignment and expression evidence for all TFs. In addition, DPTF contains cross-links to the Arabidopsis and rice transcription factor databases making it a unique resource for genome-scale comparative studies of transcriptional regulation in model plants. Availiability: DPTF is available at http://dptf.cbi.pku.edu.cn.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17392330?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Harbottle, Michael J</style></author><author><style face="normal" font="default" size="100%">Mantle, Michael D</style></author><author><style face="normal" font="default" size="100%">Johns, Michael L</style></author><author><style face="normal" font="default" size="100%">Van Herwijnen, Rene</style></author><author><style face="normal" font="default" size="100%">Al-Tabbaa, Abir</style></author><author><style face="normal" font="default" size="100%">Hutchings, Tony R</style></author><author><style face="normal" font="default" size="100%">Moffat, Andy J</style></author><author><style face="normal" font="default" size="100%">Ouki, Sabeha K</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Magnetic resonance imaging of the effect of zeolite on lithium uptake in poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental science &amp; technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Sci. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 May 15</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">41</style></volume><pages><style face="normal" font="default" size="100%">3444-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The use of a zeolite (clinoptilolite) to protect poplar plants from lithium-contaminated soil has been studied using magnetic resonance imaging. Lithium was used as a model contaminant as it could be tracked directly using specific nuclear magnetic resonance probes, rather than relying on relaxation time effects on protons due to paramagnetic solutes. The sorption of lithium to the zeolite was investigated both in static and dynamic systems; lithium was found to sorb readily to the zeolite over time. Poplar plants were grown in soil microcosms consisting of either sand or sand and zeolite with nutrients provided through the use of Hoagland's solution as the pore fluid. Both one-dimensional profiles of lithium concentration along poplar stems and direct lithium imaging of stem cross-sections were employed to reveal the uptake of the contaminant into the plant structure, showing significantly less lithium present in plants grown in sand and zeolite than those grown in sand alone. Evidence of structural features involved in the uptake of lithium was also obtained.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17547161?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Peiter, Edgar</style></author><author><style face="normal" font="default" size="100%">Montanini, Barbara</style></author><author><style face="normal" font="default" size="100%">Gobert, Anthony</style></author><author><style face="normal" font="default" size="100%">Pedas, Pai</style></author><author><style face="normal" font="default" size="100%">Husted, Søren</style></author><author><style face="normal" font="default" size="100%">Maathuis, Frans J M</style></author><author><style face="normal" font="default" size="100%">Blaudez, Damien</style></author><author><style face="normal" font="default" size="100%">Chalot, Michel</style></author><author><style face="normal" font="default" size="100%">Sanders, Dale</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A secretory pathway-localized cation diffusion facilitator confers plant manganese tolerance.</style></title><secondary-title><style face="normal" font="default" size="100%">Proceedings of the National Academy of Sciences of the United States of America</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Proc. Natl. Acad. Sci. U.S.A.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 May 15</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">104</style></volume><pages><style face="normal" font="default" size="100%">8532-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Manganese toxicity is a major problem for plant growth in acidic soils, but cellular mechanisms that facilitate growth in such conditions have not been clearly delineated. Established mechanisms that counter metal toxicity in plants involve chelation and cytoplasmic export of the metal across the plasma or vacuolar membranes out of the cell or sequestered into a large organelle, respectively. We report here that expression of the Arabidopsis and poplar MTP11 cation diffusion facilitators in a manganese-hypersensitive yeast mutant restores manganese tolerance to wild-type levels. Microsomes from yeast expressing AtMTP11 exhibit enhanced manganese uptake. In accord with a presumed function of MTP11 in manganese tolerance, Arabidopsis mtp11 mutants are hypersensitive to elevated levels of manganese, whereas plants overexpressing MTP11 are hypertolerant. In contrast, sensitivity to manganese deficiency is slightly decreased in mutants and increased in overexpressing lines. Promoter-GUS studies showed that AtMTP11 is most highly expressed in root tips, shoot margins, and hydathodes, but not in epidermal cells and trichomes, which are generally associated with manganese accumulation. Surprisingly, imaging of MTP11-EYFP fusions demonstrated that MTP11 localizes neither to the plasma membrane nor to the vacuole, but to a punctate endomembrane compartment that largely coincides with the distribution of the trans-Golgi marker sialyl transferase. Golgi-based manganese accumulation might therefore result in manganese tolerance through vesicular trafficking and exocytosis. In accord with this proposal, Arabidopsis mtp11 mutants exhibit enhanced manganese concentrations in shoots and roots. We propose that Golgi-mediated exocytosis comprises a conserved mechanism for heavy metal tolerance in plants.</style></abstract><issue><style face="normal" font="default" size="100%">20</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17494768?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rouhier, Nicolas</style></author><author><style face="normal" font="default" size="100%">Unno, Hideaki</style></author><author><style face="normal" font="default" size="100%">Bandyopadhyay, Sibali</style></author><author><style face="normal" font="default" size="100%">Masip, Lluis</style></author><author><style face="normal" font="default" size="100%">Kim, Sung-Kun</style></author><author><style face="normal" font="default" size="100%">Hirasawa, Masakazu</style></author><author><style face="normal" font="default" size="100%">Gualberto, José Manuel</style></author><author><style face="normal" font="default" size="100%">Lattard, Virginie</style></author><author><style face="normal" font="default" size="100%">Kusunoki, Masami</style></author><author><style face="normal" font="default" size="100%">Knaff, David B</style></author><author><style face="normal" font="default" size="100%">Georgiou, George</style></author><author><style face="normal" font="default" size="100%">Hase, Toshiharu</style></author><author><style face="normal" font="default" size="100%">Johnson, Michael K</style></author><author><style face="normal" font="default" size="100%">Jacquot, Jean-Pierre</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Functional, structural, and spectroscopic characterization of a glutathione-ligated [2Fe-2S] cluster in poplar glutaredoxin C1.</style></title><secondary-title><style face="normal" font="default" size="100%">Proceedings of the National Academy of Sciences of the United States of America</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Proc. Natl. Acad. Sci. U.S.A.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 May 1</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">104</style></volume><pages><style face="normal" font="default" size="100%">7379-84</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">When expressed in Escherichia coli, cytosolic poplar glutaredoxin C1 (CGYC active site) exists as a dimeric iron-sulfur-containing holoprotein or as a monomeric apoprotein in solution. Analytical and spectroscopic studies of wild-type protein and site-directed variants and structural characterization of the holoprotein by using x-ray crystallography indicate that the holoprotein contains a subunit-bridging [2Fe-2S] cluster that is ligated by the catalytic cysteines of two glutaredoxins and the cysteines of two glutathiones. Mutagenesis data on a variety of poplar glutaredoxins suggest that the incorporation of an iron-sulfur cluster could be a general feature of plant glutaredoxins possessing a glycine adjacent to the catalytic cysteine. In light of these results, the possible involvement of plant glutaredoxins in oxidative stress sensing or iron-sulfur biosynthesis is discussed with respect to their intracellular localization.</style></abstract><issue><style face="normal" font="default" size="100%">18</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17460036?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lindroth, Richard L</style></author><author><style face="normal" font="default" size="100%">Donaldson, Jack R</style></author><author><style face="normal" font="default" size="100%">Stevens, Michael T</style></author><author><style face="normal" font="default" size="100%">Gusse, Adam C</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Browse quality in quaking Aspen (Populus tremuloides): effects of genotype, nutrients, defoliation, and coppicing.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of chemical ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Chem. Ecol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">33</style></volume><pages><style face="normal" font="default" size="100%">1049-64</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The consequences of interactions among genetic, ontogenetic, and environmental factors for the quality of winter-dormant tissues as food for browsing herbivores is poorly understood. We conducted two sequential common garden studies to assess the impacts of intraspecific genetic variation, nutrient availability, prior defoliation, and ontogenetic stage on the chemical quality of winter-dormant tissue in quaking aspen (Populus tremuloides Michx.). In the first study, saplings of 12 aspen genotypes were grown under low and high soil nutrient conditions, with or without two successive seasons of defoliation. Quantity and quality of current year's twig growth were assessed. Twig production varied among genotypes and declined under low nutrient availability, but showed little response to prior defoliation. Chemical quality of sapling twigs varied substantially among genotypes, and in response to nutrient availability and prior defoliation. Overall, browse quality improved (nitrogen levels increased while phenolic glycoside and condensed tannin levels decreased) after defoliation. Growth and chemical variables exhibited low to moderate clonal repeatability (broad sense heritability) values. Our second study employed the same 12 genotypes, grown under high-nutrient conditions and with or without two seasons of defoliation. The trees were coppiced to produce root sprouts, which were chemically assessed 1 yr later. Rejuvenation via coppicing led to increased levels of nitrogen, phenolic glycosides (salicortin), and tannins in root sprouts, and the magnitude of change varied among aspen genotypes. Signatures of defoliation nearly 2 yr earlier persisted in terms of elevated levels of phenolic glycosides in root sprouts of previously defoliated trees. Aspen forests likely present browsing herbivores with chemically heterogeneous environments because of the interactions of genetic, ontogenetic, and environmental factors that vary over space and time.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17404817?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Brown, Valerie J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Cottonwood clues in Fallon. Tree rings reflect tungsten, cobalt exposure.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental health perspectives</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Health Perspect.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">115</style></volume><pages><style face="normal" font="default" size="100%">A263</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17520048?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bohler, Sacha</style></author><author><style face="normal" font="default" size="100%">Bagard, Matthieu</style></author><author><style face="normal" font="default" size="100%">Oufir, Mouhssin</style></author><author><style face="normal" font="default" size="100%">Planchon, Sébastien</style></author><author><style face="normal" font="default" size="100%">Hoffmann, Lucien</style></author><author><style face="normal" font="default" size="100%">Jolivet, Yves</style></author><author><style face="normal" font="default" size="100%">Hausman, Jean-François</style></author><author><style face="normal" font="default" size="100%">Dizengremel, Pierre</style></author><author><style face="normal" font="default" size="100%">Renaut, Jenny</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A DIGE analysis of developing poplar leaves subjected to ozone reveals major changes in carbon metabolism.</style></title><secondary-title><style face="normal" font="default" size="100%">Proteomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Proteomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">7</style></volume><pages><style face="normal" font="default" size="100%">1584-99</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Tropospheric ozone pollution is described as having major negative effects on plants, compromising plant survival. Carbon metabolism is especially affected. In the present work, the effects of chronic ozone exposure were evaluated at the proteomic level in developing leaves of young poplar plants exposed to 120 ppb of ozone for 35 days. Soluble proteins (excluding intrinsic membrane proteins) were extracted from leaves after 3, 14 and 35 days of ozone exposure, as well as 10 days after a recovery period. Proteins (pI 4 to 7) were analyzed by 2-D DIGE experiments, followed by MALDI-TOF-TOF identification. Additional observations were obtained on growth, lesion formation, and leaf pigments analysis. Although treated plants showed large necrotic spots and chlorosis in mature leaves, growth decreased only slightly and plant height was not affected. The number of abscised leaves was higher in treated plants, but new leaf formation was not affected. A decrease in chlorophylls and lutein contents was recorded. A large number of proteins involved in carbon metabolism were identified. In particular, proteins associated with the Calvin cycle and electron transport in the chloroplast were down-regulated. In contrast, proteins associated with glucose catabolism increased in response to ozone exposure. Other identified enzymes are associated with protein folding, nitrogen metabolism and oxidoreductase activity.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17486556?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Samuelson, Lisa J</style></author><author><style face="normal" font="default" size="100%">Stokes, Thomas A</style></author><author><style face="normal" font="default" size="100%">Coleman, Mark D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Influence of irrigation and fertilization on transpiration and hydraulic properties of Populus deltoides.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">27</style></volume><pages><style face="normal" font="default" size="100%">765-74</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Long-term hydraulic acclimation to resource availability was explored in 3-year-old Populus deltoides Bartr. ex Marsh. clones by examining transpiration, leaf-specific hydraulic conductance (G(L)), canopy stomatal conductance (G(S)) and leaf to sapwood area ratio (A(L):A(S)) in response to irrigation (13 and 551 mm year(-1) in addition to ambient precipitation) and fertilization (0 and 120 kg N ha(-1) year(-1)). Sap flow was measured continuously over one growing season with thermal dissipation probes. Fertilization had a greater effect on growth and hydraulic properties than irrigation, and fertilization effects were independent of irrigation treatment. Transpiration on a ground area basis (E) ranged between 0.3 and 1.8 mm day(-1), and increased 66% and 90% in response to irrigation and fertilization, respectively. Increases in G(L), G(S) at a reference vapor pressure deficit of 1 kPa, and transpiration per unit leaf area in response to increases in resource availability were associated with reductions in A(L):A(S) and consequently a minimal change in the water potential gradient from soil to leaf. Irrigation and fertilization increased leaf area index similarly, from an average 1.16 in control stands to 1.45, but sapwood area was increased from 4.0 to 6.3 m(2) ha(-1) by irrigation and from 3.7 to 6.7 m(2) ha(-1) by fertilization. The balance between leaf area and sapwood area was important in understanding long-term hydraulic acclimation to resource availability and mechanisms controlling maximum productivity in Populus deltoides.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17267367?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Calfapietra, Carlo</style></author><author><style face="normal" font="default" size="100%">Wiberley, Amy E</style></author><author><style face="normal" font="default" size="100%">Falbel, Tanya G</style></author><author><style face="normal" font="default" size="100%">Linskey, Autumn R</style></author><author><style face="normal" font="default" size="100%">Mugnozza, Giuseppe Scarascia</style></author><author><style face="normal" font="default" size="100%">Karnosky, David F</style></author><author><style face="normal" font="default" size="100%">Loreto, Francesco</style></author><author><style face="normal" font="default" size="100%">Sharkey, Thomas D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Isoprene synthase expression and protein levels are reduced under elevated O3 but not under elevated CO2 (FACE) in field-grown aspen trees.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">30</style></volume><pages><style face="normal" font="default" size="100%">654-61</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Emission of hydrocarbons by trees has a crucial role in the oxidizing potential of the atmosphere. In particular, isoprene oxidation leads to the formation of tropospheric ozone and other secondary pollutants. It is expected that changes in the composition of the atmosphere will influence the emission rate of isoprene, which may in turn feedback on the accumulation of pollutants and greenhouse gases. We investigated the isoprene synthase (ISPS) gene expression and the ISPS protein levels in aspen trees exposed to elevated ozone (O(3)) and/or elevated carbon dioxide (CO(2)) in field-grown trees at the Aspen Free-Air Carbon Dioxide Enrichment (FACE) experimental site. Elevated O(3) reduced ISPS mRNA and the amount of ISPS protein in aspen leaves, whereas elevated CO(2) had no significant effect. Aspen clones with different O(3) sensitivity showed different levels of inhibition under elevated O(3) conditions. The drop in ISPS protein levels induced a drop in the isoprene emission rate under elevated O(3). However, the data indicated that other mechanisms also contributed to the observed strong inhibition of isoprene emission under elevated O(3).</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17407542?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhou, Gong-Ke</style></author><author><style face="normal" font="default" size="100%">Zhong, Ruiqin</style></author><author><style face="normal" font="default" size="100%">Himmelsbach, David S</style></author><author><style face="normal" font="default" size="100%">McPhail, Brooks T</style></author><author><style face="normal" font="default" size="100%">Ye, Zheng-Hua</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Molecular characterization of PoGT8D and PoGT43B, two secondary wall-associated glycosyltransferases in poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant &amp; cell physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">48</style></volume><pages><style face="normal" font="default" size="100%">689-99</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Dicot wood is mainly composed of cellulose, lignin and glucuronoxylan (GX). Although the biosynthetic genes for cellulose and lignin have been studied intensively, little is known about the genes involved in the biosynthesis of GX during wood formation. Here, we report the molecular characterization of two genes, PoGT8D and PoGT43B, which encode putative glycosyltransferases, in the hybrid poplar Populus alba x tremula. The predicted amino acid sequences of PoGT8D and PoGT43B exhibit 89 and 75% similarity to the Arabidopsis thaliana IRREGULAR XYLEM8 (IRX8) and IRX9, respectively, both of which have been shown to be required for GX biosynthesis. The PoGT8D and PoGT43B genes were found to be expressed in cells undergoing secondary wall thickening, including the primary xylem, secondary xylem and phloem fibers in stems, and the secondary xylem in roots. Both PoGT8D and PoGT43B are predicted to be type II membrane proteins and shown to be targeted to Golgi. Overexpression of PoGT43B in the irx9 mutant was able to rescue the defects in plant size and secondary wall thickness and partially restore the xylose content. Taken together, our results demonstrate that PoGT8D and PoGT43B are Golgi-localized, secondary wall-associated proteins, and PoGT43B is a functional ortholog of IRX9 involved in GX biosynthesis during wood formation.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17379696?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Obase, Keisuke</style></author><author><style face="normal" font="default" size="100%">Tamai, Yutaka</style></author><author><style face="normal" font="default" size="100%">Yajima, Takashi</style></author><author><style face="normal" font="default" size="100%">Miyamoto, Toshizumi</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Mycorrhizal associations in woody plant species at the Mt. Usu volcano, Japan.</style></title><secondary-title><style face="normal" font="default" size="100%">Mycorrhiza</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mycorrhiza</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">17</style></volume><pages><style face="normal" font="default" size="100%">209-15</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We investigated the association between ectomycorrhizal (ECM) and arbuscular mycorrhizal (AM) fungi and pioneer woody plant species in areas devastated by the eruption of Mt. Usu, Japan, in 2000. We observed eight woody plant species at the research site, most of which were associated with ECM and/or AM fungi. In particular, dominant woody plant species Populus maximowiczii, Salix hultenii var. angustifolia and Salix sachalinensis were consistently associated with ECM fungi and erratically associated with AM fungi. We found one to six morphotypes in the roots of each ECM host and, on average, two in the roots of each seedling, indicating low ECM fungal diversity. ECM colonization ranged from 17 to 42% of root tips. Using morphotyping and molecular analyses, 15 ECM fungi were identified. ECM fungi differed greatly between hosts. However, Laccaria amethystea, Hebeloma mesophaeum, Thelephora terrestris and other Thelephoraceae had high relative colonization, constituting the majority of the ECM colonization in the roots of each plant species. These ECM fungi may be important for the establishment of pioneer woody plant species and further revegetation at Mt. Usu volcano.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17216274?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Loreto, Francesco</style></author><author><style face="normal" font="default" size="100%">Centritto, Mauro</style></author><author><style face="normal" font="default" size="100%">Barta, Csengele</style></author><author><style face="normal" font="default" size="100%">Calfapietra, Carlo</style></author><author><style face="normal" font="default" size="100%">Fares, Silvano</style></author><author><style face="normal" font="default" size="100%">Monson, Russell K</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The relationship between isoprene emission rate and dark respiration rate in white poplar (Populus alba L.) leaves.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">30</style></volume><pages><style face="normal" font="default" size="100%">662-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In past studies, it was hypothesized that reductions in chloroplast isoprene emissions at high atmospheric CO(2) concentrations were caused by competition between cytosolic and mitochondrial processes for the same substrate, possibly phosphoenolpyruvate (PEP). We conducted field and laboratory experiments using leaves of white poplar (Populus alba L.) to identify whether an inverse relationship occurs between the dark respiration rate (a mitochondrial process) and the isoprene emission rate. Field experiments that were carried out in a free-air CO(2)-enriched (FACE) facility showed no clear effect of elevated CO(2) on either isoprene emission rate or respiration rate by leaves. In young, not yet fully expanded leaves, low isoprene emission and high dark respiration rates were measured in both ambient and elevated CO(2). In these leaves, isoprene emission was inversely correlated with dark respiration. It is possible to interpret from these results that, in young leaves, high rates of growth respiration compete with isoprene biosynthesis for the same substrate. However, it is also possible that the negative correlation reflects the contrasting reductions in growth respiration and increases in expression of the enzyme isoprene synthase at this final stage of leaf maturation. In contrast to our observations on young leaves, respiration rate and isoprene emission rate were positively correlated in older, fully expanded leaves (8 and 11 from apex). A positive correlation was also found between respiration rate and isoprene emission rate when these parameters were modulated using different ozone exposure, growth light intensity, growth temperature and exposure to different leaf temperatures in laboratory experiments. These data show that competition for substrate between isoprene biosynthesis and leaf respiration does not determine the rate of isoprene emission in most circumstances that affect both processes. A negative correlation was observed across all experiments between isoprene emission rate and the activity of phosphoenolpyruvate carboxylase (PEPc), a cytosolic enzyme that competes with isoprene biosynthesis for substrate. The cytosolic metabolite, PEP, occurs at a metabolic branch point from which substrate flows into three processes: (1) the production of pyruvate for mitochondrial respiration, (2) the production of oxaloacetate (OAA) by PEPc for anabolic support of mitochondrial respiration and (3) transport into the chloroplast to support chloroplastic demands for pyruvate, including isoprenoid biosynthesis. The results of our observations suggest that only the second process competes for substrate with isoprenoid synthesis, while the partitioning of PEP between mitochondrial respiration and chloroplast isoprenoid biosynthesis is controlled in a way that retains balance in substrate demand.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17407543?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sheppard, Paul R</style></author><author><style face="normal" font="default" size="100%">Speakman, Robert J</style></author><author><style face="normal" font="default" size="100%">Ridenour, Gary</style></author><author><style face="normal" font="default" size="100%">Witten, Mark L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Temporal variability of tungsten and cobalt in Fallon, Nevada.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental health perspectives</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Health Perspect.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">115</style></volume><pages><style face="normal" font="default" size="100%">715-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Since 1997, Fallon, Nevada, has experienced a cluster of childhood leukemia that has been declared &quot;one of the most unique clusters of childhood cancer ever reported.&quot; Multiple environmental studies have shown airborne tungsten and cobalt to be elevated within Fallon, but the question remains: Have these metals changed through time in correspondence with the onset of the leukemia cluster?</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17520058?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rinaldi, Cécile</style></author><author><style face="normal" font="default" size="100%">Kohler, Annegret</style></author><author><style face="normal" font="default" size="100%">Frey, Pascal</style></author><author><style face="normal" font="default" size="100%">Duchaussoy, Frédéric</style></author><author><style face="normal" font="default" size="100%">Ningre, Nathalie</style></author><author><style face="normal" font="default" size="100%">Couloux, Arnaud</style></author><author><style face="normal" font="default" size="100%">Wincker, Patrick</style></author><author><style face="normal" font="default" size="100%">Le Thiec, Didier</style></author><author><style face="normal" font="default" size="100%">Fluch, Silvia</style></author><author><style face="normal" font="default" size="100%">Martin, Francis</style></author><author><style face="normal" font="default" size="100%">Duplessis, Sébastien</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Transcript profiling of poplar leaves upon infection with compatible and incompatible strains of the foliar rust Melampsora larici-populina.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">144</style></volume><pages><style face="normal" font="default" size="100%">347-66</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">To understand key processes governing defense mechanisms in poplar (Populus spp.) upon infection with the rust fungus Melampsora larici-populina, we used combined histological and molecular techniques to describe the infection of Populus trichocarpa x Populus deltoides 'Beaupré' leaves by compatible and incompatible fungal strains. Striking differences in host-tissue infection were observed after 48-h postinoculation (hpi) between compatible and incompatible interactions. No reactive oxygen species production could be detected at infection sites, while a strong accumulation of monolignols occurred in the incompatible interaction after 48 hpi, indicating a late plant response once the fungus already penetrated host cells to form haustorial infection structures. P. trichocarpa whole-genome expression oligoarrays and sequencing of cDNAs were used to determine changes in gene expression in both interactions at 48 hpi. Temporal expression profiling of infection-regulated transcripts was further compared by cDNA arrays and reverse transcription-quantitative polymerase chain reaction. Among 1,730 significantly differentially expressed transcripts in the incompatible interaction, 150 showed an increase in concentration &gt; or =3-fold, whereas 62 were decreased by &gt; or =3-fold. Regulated transcripts corresponded to known genes targeted by R genes in plant pathosystems, such as inositol-3-P synthase, glutathione S-transferases, and pathogenesis-related proteins. However, the transcript showing the highest rust-induced up-regulation encodes a putative secreted protein with no known function. In contrast, only a few transcripts showed an altered expression in the compatible interaction, suggesting a delay in defense response between incompatible and compatible interactions in poplar. This comprehensive analysis of early molecular responses of poplar to M. larici-populina infection identified key genes that likely contain the fungus proliferation in planta. Sequences from the SSH library described in this article can be retrieved in GenBank under accession numbers CT 027996 to CT 029994 and CT 033829.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17400708?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Li, Qin</style></author><author><style face="normal" font="default" size="100%">Zhai, Jianping</style></author><author><style face="normal" font="default" size="100%">Zhang, Wenyi</style></author><author><style face="normal" font="default" size="100%">Wang, Mingmei</style></author><author><style face="normal" font="default" size="100%">Zhou, Jun</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Kinetic studies of adsorption of Pb(II), Cr(III) and Cu(II) from aqueous solution by sawdust and modified peanut husk.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of hazardous materials</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Hazard. Mater.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Mar 6</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">141</style></volume><pages><style face="normal" font="default" size="100%">163-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Sawdust and modified peanut husk were used as adsorbents to remove Pb(II), Cr(III) and Cu(II) from aqueous solution. Results of kinetic experiments demonstrated that the adsorption was effective and rapid. Three different kinds of kinetic models (i.e., intraparticular diffusion model, Lagergren-first-order and second-order equations) were used to investigate the adsorption mechanisms. The adsorption of heavy metals on sawdust and modified peanut husk is not an intraparticular diffusion control. The kinetic adsorption data can be described by the second-order equation and the adsorption might be a rate-limiting control. The suitability of the adsorbent was tested by fitting the adsorption data with Langmuir and Freundlich isotherms, which gave good fits with both isotherms.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16930824?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Meng, Meng</style></author><author><style face="normal" font="default" size="100%">Geisler, Matt</style></author><author><style face="normal" font="default" size="100%">Johansson, Henrik</style></author><author><style face="normal" font="default" size="100%">Mellerowicz, Ewa J</style></author><author><style face="normal" font="default" size="100%">Karpinski, Stanislaw</style></author><author><style face="normal" font="default" size="100%">Kleczkowski, Leszek A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Differential tissue/organ-dependent expression of two sucrose- and cold-responsive genes for UDP-glucose pyrophosphorylase in Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">Gene</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Gene</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Mar 15</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">389</style></volume><pages><style face="normal" font="default" size="100%">186-95</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Plant UDP-glucose (UDPG) pyrophosphorylase (UGPase) is involved in the production/metabolism of UDPG, a key metabolite for sucrose and cell wall biosynthesis. Two highly similar cDNAs (UGP1 and UGP2) corresponding to UGPase were isolated from cDNA libraries of hybrid aspen (Populus tremula x tremuloides). Expression of both UGPs, as studied by DNA microarrays and EST abundance, was compared to that of three sucrose synthase genes (SUS1-3), also involved in UDPG synthesis. Generally, the UGPs had lower expression than SUS1 and SUS2 genes (especially in tension wood and cambium), with the notable exception of leaves, primary roots and flowers. Based on real-time quantitative PCR, UGP1 in root xylem, leaves and male flowers was by far the predominant transcript, while in other tissues both UGP1 and UGP2 had comparable expression. In leaves, the UGP1 gene, but not UGP2, was upregulated by light and short-term sucrose feeding. Cold treatment led to dramatic organ-specific changes in relative expression of both genes, with UGP2 being upregulated either transiently (leaves), long-term (stems) or not at all (roots), whereas UGP1 was cold-upregulated in all organs. Individual or overall UGP expression patterns only weakly correlated with UGPase activity/protein; however, UGPase activity and protein were correlated in all tissues/conditions. The data suggest that UGPs are differentially expressed at the tissue level and in response to metabolic feedback (sucrose) and cold stress, and point to a tight posttranscriptional/translational control and, possibly, distinct roles for those genes.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17196771?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Owen, Susan M</style></author><author><style face="normal" font="default" size="100%">Clark, Stuart</style></author><author><style face="normal" font="default" size="100%">Pompe, Matevz</style></author><author><style face="normal" font="default" size="100%">Semple, Kirk T</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Biogenic volatile organic compounds as potential carbon sources for microbial communities in soil from the rhizosphere of Populus tremula.</style></title><secondary-title><style face="normal" font="default" size="100%">FEMS microbiology letters</style></secondary-title><alt-title><style face="normal" font="default" size="100%">FEMS Microbiol. Lett.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">268</style></volume><pages><style face="normal" font="default" size="100%">34-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Catabolism of a (14)C-labelled volatile monoterpene compound (geraniol) to (14)CO(2) was investigated in soils taken from the rhizosphere at distances up to 200 cm from the trunks of three small Populus tremula trees growing at different sites in Slovenia. Emissions of limonene of up to 18 microg m(-2) h(-1) were detected from the soil surface at each site. Evolution of (14)C-labelled CO(2) was measured as a product of catabolism of (14)C-labelled geraniol introduced into the soil samples. Indigenous soil microorganisms degraded the geraniol rapidly. There was a significant difference in relative lag times and rates of catabolism along the gradient from the tree trunks, with relatively longer lag times and lower rates occurring in soil samples from the farthest point from the tree.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17227464?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhou, Zhou</style></author><author><style face="normal" font="default" size="100%">Zhang, Deqiang</style></author><author><style face="normal" font="default" size="100%">Lu, Mengzhu</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Cloning and expression analysis of PtFATB gene encoding the acyl-acyl carrier protein thioesterase in Populus tomentosa Carr.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of genetics and genomics = Yi chuan xue bao</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J Genet Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">34</style></volume><pages><style face="normal" font="default" size="100%">267-73</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Acyl-ACP thioesterases (FATs) terminates the fatty acid synthesis and allow the transport of fatty acids out of the plastids, which are the important determinants of cellular metabolism. FATB is a member of FAT enzymes that has been described previously in most of the plants. In silico cloning is a new method that utilizes the bioinformatics on the complete genome and available EST database. In this study, a full-length cDNA clone of PtFATB gene was isolated from Populus tomentosa using this approach. It is 1,450 bp in length and the open reading frame encodes a peptide of 421 amino acids. The predicted amino acid sequence shows significant homology with those from other plant species, which contain typical domains owned by FATB proteins. The transcripts of PtFATB were abundant in leaves, and less in roots detected by using semiquantitative RT-PCR. When the shoots were subjected to the stress treatments (cold, dry, NaCl) and ABA (Abscisic acid), the expression of PtFATB was only slightly reduced under the treatment of low temperature. This suggests that the expression of PtFATB is in a constitutive fashion. This study provides the basis not only for the identification and characterization of this gene but also for the improvement of cold tolerance by controlling the expression of the PtFATB gene in trees in near future.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17498624?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lyyra, Satu</style></author><author><style face="normal" font="default" size="100%">Meagher, Richard B</style></author><author><style face="normal" font="default" size="100%">Kim, Tehryung</style></author><author><style face="normal" font="default" size="100%">Heaton, Andrew</style></author><author><style face="normal" font="default" size="100%">Montello, Paul</style></author><author><style face="normal" font="default" size="100%">Balish, Rebecca S</style></author><author><style face="normal" font="default" size="100%">Merkle, Scott A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Coupling two mercury resistance genes in Eastern cottonwood enhances the processing of organomercury.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant biotechnology journal</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Biotechnol. J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">5</style></volume><pages><style face="normal" font="default" size="100%">254-62</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Eastern cottonwood (Populus deltoides Bartr. ex Marsh.) trees were engineered to express merA (mercuric ion reductase) and merB (organomercury lyase) transgenes in order to be used for the phytoremediation of mercury-contaminated soils. Earlier studies with Arabidopsis thaliana and Nicotiana tabacum showed that this gene combination resulted in more efficient detoxification of organomercurial compounds than did merB alone, but neither species is optimal for long-term field applications. Leaf discs from in vitro-grown merA, nptII (neomycin phosphotransferase) transgenic cottonwood plantlets were inoculated with Agrobacterium tumefaciens strain C58 carrying the merB and hygromycin resistance (hptII) genes. Polymerase chain reaction of shoots regenerated from the leaf discs under selection indicated an overall transformation frequency of 20%. Western blotting of leaves showed that MerA and MerB proteins were produced. In vitro-grown merA/merB plants were highly resistant to phenylmercuric acetate, and detoxified organic mercury compounds two to three times more rapidly than did controls, as shown by mercury volatilization assay. This indicates that these cottonwood trees are reasonable candidates for the remediation of organomercury-contaminated sites.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17309680?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ingvarsson, Pär K</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Gene expression and protein length influence codon usage and rates of sequence evolution in Populus tremula.</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular biology and evolution</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Biol. Evol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">24</style></volume><pages><style face="normal" font="default" size="100%">836-44</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Codon bias is generally thought to be determined by a balance between mutation, genetic drift, and natural selection on translational efficiency. However, natural selection on codon usage is considered to be a weak evolutionary force and selection on codon usage is expected to be strongest in species with large effective population sizes. In this paper, I study associations between codon usage, gene expression, and molecular evolution at synonymous and nonsynonymous sites in the long-lived, woody perennial plant Populus tremula (Salicaceae). Using expression data for 558 genes derived from expressed sequence tags (EST) libraries from 19 different tissues and developmental stages, I study how gene expression levels within single tissues as well as across tissues affect codon usage and rates sequence evolution at synonymous and nonsynonymous sites. I show that gene expression have direct effects on both codon usage and the level of selective constraint of proteins in P. tremula, although in different ways. Codon usage genes is primarily determined by how highly expressed a genes is, whereas rates of sequence evolution are primarily determined by how widely expressed genes are. In addition to the effects of gene expression, protein length appear to be an important factor influencing virtually all aspects of molecular evolution in P. tremula.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17204548?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Donaldson, Jack R</style></author><author><style face="normal" font="default" size="100%">Lindroth, Richard L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genetics, environment, and their interaction determine efficacy of chemical defense in trembling aspen.</style></title><secondary-title><style face="normal" font="default" size="100%">Ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ecology</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">88</style></volume><pages><style face="normal" font="default" size="100%">729-39</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Optimal defense theories suggest that a trade-off between defense costs and benefits maintains genetic variation within plant populations. This study assessed the independent and interactive effects of genetic- and environment-based variation in aspen leaf chemistry on insect performance, preference, and defoliation. Gypsy moth larvae were released into screenhouses containing eight aspen genotypes growing with high and low levels of nutrient availability. Plant chemistry, defoliation, and larval growth rates varied in response to genotype, nutrient availability, and their interaction. Total phenolic glycoside concentrations were inversely correlated with patterns of larval preference and were the best predictor of larval performance and defoliation among genotypes. Low-nutrient trees were less heavily defoliated and afforded decreased larval growth rates compared with high-nutrient trees. Nutrient availability mediated the defense benefits of phenolic glycosides, as plant chemistry explained significantly less variation in defoliation in low- compared with high-nutrient trees (7% vs. 44% of variation explained). These results suggest that spatial and temporal variation in resource availability may influence the relative magnitude of defense benefits in plants. Environmental mediation of the defense costs and benefits likely leads to diversifying selection and may maintain genetic polymorphisms in chemical defense traits in plant populations.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17503600?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Thomas, Carla N</style></author><author><style face="normal" font="default" size="100%">Bauerle, William L</style></author><author><style face="normal" font="default" size="100%">Owino, Tom O</style></author><author><style face="normal" font="default" size="100%">Chastain, John P</style></author><author><style face="normal" font="default" size="100%">Klaine, Stephen J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Influence of brick air scrubber by-product on growth and development of corn and hybrid poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioresource technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bioresour. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">98</style></volume><pages><style face="normal" font="default" size="100%">1085-94</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Studies were conducted to determine the effects of spent reagent from air pollution control scrubbers used at a brick manufacturing facility on emergence, growth, and physiological responses of corn and hybrid poplar plants. Scrubber by-product was obtained from General Shale Brick, Louisville, KY. Potting substrate was weighed and quantities of scrubber by-product were added to the substrate to obtain treatments of 0%, 6.25%, 12.5%, 25%, 50%, 75%, and 100% scrubber by-product (w:w) for the corn study. Each treatment mix was potted into nine replicate polyethylene pots and four corn seeds were sown per pot. The pots were randomized in a greenhouse at Clemson University and the number of seedlings emerging from each treatment, dark-adapted leaf chlorophyll a fluorescence, and shoot heights were measured at the end of a 21-day growth period. Then, dry shoot biomass was determined for plants from each treatment and plant tissues were analyzed for selected constituents. For the poplar study, nine-inch cuttings of hybrid poplar clone 15-29 (Populus trichocarpa x P. deltoides) and clone OP367 (P. deltoides x P. nigra) were planted in treatments of scrubber by-product-potting soil mixes of 0% , 5% , 10% , and 25% w:w. Leaf chlorophyll a fluorescence was measured over six weeks and cumulative leaf area, dry biomass, and nutrient content of tissues were determined upon harvest. Results of these studies indicate that percent seedling emergence for corn plants decreased with increasing scrubber by-product application rates. Application rates up to 12.5% scrubber by-product w:w had no adverse effect on corn seedling emergence. Shoot elongation, biomass production, and the status of the photosynthetic apparatus of the seedlings were also not severely impaired at applications below this level. A critical value of 58.2% w:w scrubber by-product was estimated to cause 25% inhibition of seedling emergence. Biomass production, cumulative leaf area, and chlorophyll a fluorescence of hybrid poplar plants were not affected by scrubber by-product applications of up to 5% w:w.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16762547?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Langenfeld-Heyser, R</style></author><author><style face="normal" font="default" size="100%">Gao, J</style></author><author><style face="normal" font="default" size="100%">Ducic, T</style></author><author><style face="normal" font="default" size="100%">Tachd, Ph</style></author><author><style face="normal" font="default" size="100%">Lu, C F</style></author><author><style face="normal" font="default" size="100%">Fritz, E</style></author><author><style face="normal" font="default" size="100%">Gafur, A</style></author><author><style face="normal" font="default" size="100%">Polle, A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Paxillus involutus mycorrhiza attenuate NaCl-stress responses in the salt-sensitive hybrid poplar Populusxcanescens.</style></title><secondary-title><style face="normal" font="default" size="100%">Mycorrhiza</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mycorrhiza</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">17</style></volume><pages><style face="normal" font="default" size="100%">121-31</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In order to characterise the effect of ectomycorrhiza on Na+-responses of the salt-sensitive poplar hybrid Populus x canescens, growth and stress responses of Paxillus involutus (strain MAJ) were tested in liquid cultures in the presence of 20 to 500 mM NaCl, and the effects of mycorrhization on mineral nutrient accumulation and oxidative stress were characterised in mycorrhizal and non-mycorrhizal poplar seedlings exposed to 150 mM NaCl. Paxillus involutus was salt tolerant, showing biomass increases in media containing up to 500 mM NaCl after 4 weeks growth. Mycorrhizal mantle formation on poplar roots was not affected by 150 mM NaCl. Whole plant performance was positively affected by the fungus because total biomass was greater and leaves accumulated less Na+ than non-mycorrhizal plants. Energy dispersive X-ray microanalysis using transmission electron microscopy analysis of the influence of mycorrhization on the subcellular localisation of Na+ and Cl- in roots showed that the hyphal mantle did not diminish salt accumulation in root cell walls, indicating that mycorrhization did not provide a physical barrier against excess salinity. In the absence of salt stress, mycorrhizal poplar roots contained higher Na+ and Cl- concentrations than non-mycorrhizal poplar roots. Paxillus involutus hyphae produced H2O2 in the mantle but not in the Hartig net or in pure culture. Salt exposure resulted in H2O2 formation in cortical cells of both non-mycorrhizal and mycorrhizal poplar and stimulated peroxidase but not superoxide dismutase activities. This shows that mature ectomycorrhiza was unable to suppress salt-induced oxidative stress. Element analyses suggest that improved performance of mycorrhizal poplar under salt stress may result from diminished xylem loading of Na+ and increased supply with K+.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17115201?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Komárek, Michael</style></author><author><style face="normal" font="default" size="100%">Tlustos, Pavel</style></author><author><style face="normal" font="default" size="100%">Száková, Jirina</style></author><author><style face="normal" font="default" size="100%">Chrastný, Vladislav</style></author><author><style face="normal" font="default" size="100%">Ettler, Vojtech</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The use of maize and poplar in chelant-enhanced phytoextraction of lead from contaminated agricultural soils.</style></title><secondary-title><style face="normal" font="default" size="100%">Chemosphere</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Chemosphere</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">67</style></volume><pages><style face="normal" font="default" size="100%">640-51</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Chelant-enhanced phytoextraction of heavy metals is an emerging technological approach for a non-destructive remediation of contaminated soils. The main objectives of this study were (i) to assess the extraction efficiency of two different synthetic chelating agents (ethylenediaminetetraacetic acid (EDTA) and ethylenediaminedisuccinic acid (EDDS)) for desorbing Pb from two contaminated agricultural soils originating from a mining and smelting district and (ii) to assess the phytoextraction efficiency of maize (Zea mays) and poplar (Populus sp.) after EDTA application. EDTA was more efficient than EDDS in desorbing and complexing Pb from both soils, removing as much as 60% of Pb. Maize exhibited better results than poplar when extracting Pb from the more acidic (pH approximately 4) and more contaminated (up to 1360 mg Pb kg(-1)) agricultural soil originating from the smelting area. On the other hand, poplars proved to be more efficient when grown on the near-neutral (pH approximately 6) and less contaminated (up to 200 mg Pb kg(-1)) agricultural soil originating from the mining area. Furthermore, the addition of EDTA led to a significant increase of Pb content especially in poplar leaves, proving a strong translocation rate within the poplar plants.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17184814?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Arnaud, Dominique</style></author><author><style face="normal" font="default" size="100%">Déjardin, Annabelle</style></author><author><style face="normal" font="default" size="100%">Leplé, Jean-Charles</style></author><author><style face="normal" font="default" size="100%">Lesage-Descauses, Marie-Claude</style></author><author><style face="normal" font="default" size="100%">Pilate, Gilles</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genome-wide analysis of LIM gene family in Populus trichocarpa, Arabidopsis thaliana, and Oryza sativa.</style></title><secondary-title><style face="normal" font="default" size="100%">DNA research : an international journal for rapid publication of reports on genes and genomes</style></secondary-title><alt-title><style face="normal" font="default" size="100%">DNA Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jun 30</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">14</style></volume><pages><style face="normal" font="default" size="100%">103-16</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In Eukaryotes, LIM proteins act as developmental regulators in basic cellular processes such as regulating the transcription or organizing the cytoskeleton. The LIM domain protein family in plants has mainly been studied in sunflower and tobacco plants, where several of its members exhibit a specific pattern of expression in pollen. In this paper, we finely characterized in poplar six transcripts encoding these proteins. In Populus trichocarpa genome, the 12 LIM gene models identified all appear to be duplicated genes. In addition, we describe several new LIM domain proteins deduced from Arabidopsis and rice genomes, raising the number of LIM gene models to six for both species. Plant LIM genes have a core structure of four introns with highly conserved coding regions. We also identified new LIM domain proteins in several other species, and a phylogenetic analysis of plant LIM proteins reveals that they have undergone one or several duplication events during the evolution. We gathered several LIM protein members within new monophyletic groups. We propose to classify the plant LIM proteins into four groups: alphaLIM1, betaLIM1, gammaLIM2, and deltaLIM2, subdivided according to their specificity to a taxonomic class and/or to their tissue-specific expression. Our investigation of the structure of the LIM domain proteins revealed that they contain many conserved motifs potentially involved in their function.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17573466?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhou, Meng</style></author><author><style face="normal" font="default" size="100%">Tong, Chunfa</style></author><author><style face="normal" font="default" size="100%">Shi, Jisen</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Analysis of codon usage between different poplar species.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of genetics and genomics = Yi chuan xue bao</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J Genet Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">34</style></volume><pages><style face="normal" font="default" size="100%">555-61</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Codon usage is the selective and nonrandom use of synonymous codons to encode amino acids in genes for proteins. The analysis of codon usage may improve the understanding of codon preferences between different species and allow to rebuild the codons of exogenous genes to increase the expression efficiency of exogenous genes. Here, codon DNA sequence (CDS) of four poplar species, including Populus tremuloides Michx., P. tomentosa Carr., P. deltoides Marsh., and P. trichocarpa Torr. &amp; Gray., is used to analyze the relative frequency of synonymous codon (RFSC). High-frequency codons are selected by high-frequency (HF) codon analysis. The results indicate that the codon usage is common for all four poplar species and the codon preference is quite similar among the four poplar species. However, CCT encoding for Pro, and ACT coding for Thr are the preferred codons in P. tremuloides and P. tomentosa, whereas CCA coding for Pro, and ACA coding for Thr are preferred in P. deltoides and P. trichocarpa. The codons such as TGC coding for Cys, TTC coding for Phe, and AAG coding for Lys, are preferred in the poplar species except P. trichocarpa. GAG coding for Glu is preferred only in P. deltoides, while the other three poplar species prefer to use GAA. The commonness of preferred codon allows exogenous gene designed by the preferred codon of one of the different poplar species to be used in other poplar species.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17601615?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Loivamäki, Maaria</style></author><author><style face="normal" font="default" size="100%">Gilmer, Frank</style></author><author><style face="normal" font="default" size="100%">Fischbach, Robert J</style></author><author><style face="normal" font="default" size="100%">Sörgel, Christoph</style></author><author><style face="normal" font="default" size="100%">Bachl, Anette</style></author><author><style face="normal" font="default" size="100%">Walter, Achim</style></author><author><style face="normal" font="default" size="100%">Schnitzler, Jörg-Peter</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Arabidopsis, a model to study biological functions of isoprene emission?</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">144</style></volume><pages><style face="normal" font="default" size="100%">1066-78</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The volatile hemiterpene isoprene is emitted from plants and can affect atmospheric chemistry. Although recent studies indicate that isoprene can enhance thermotolerance or quench oxidative stress, the underlying physiological mechanisms are largely unknown. In this work, Arabidopsis (Arabidopsis thaliana), a natural nonemitter of isoprene and the model plant for functional plant analyses, has been constitutively transformed with the isoprene synthase gene (PcISPS) from Grey poplar (Populus x canescens). Overexpression of poplar ISPS in Arabidopsis resulted in isoprene-emitting rosettes that showed transiently enhanced growth rates compared to the wild type under moderate thermal stress. The findings that highest growth rates, higher dimethylallyl diphosphate levels, and enzyme activity were detected in young plants during their vegetative growth phase indicate that enhanced growth of transgenic plants under moderate thermal stress is due to introduced PcISPS. Dynamic gas-exchange studies applying transient cycles of heat stress to the wild type demonstrate clearly that the prime physiological role of isoprene formation in Arabidopsis is not to protect net assimilation from damage against thermal stress, but may instead be to retain the growth potential or coordinated vegetative development of the plant. Hence, this study demonstrates the enormous potential but also the pitfalls of transgenic Arabidopsis (or other nonnatural isoprenoid emitters) in studying isoprene biosynthesis and its biological function(s).</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17468218?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Auble, Gregor T</style></author><author><style face="normal" font="default" size="100%">Shafroth, Patrick B</style></author><author><style face="normal" font="default" size="100%">Scott, Michael L</style></author><author><style face="normal" font="default" size="100%">Roelle, James E</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Early vegetation development on an exposed reservoir: implications for dam removal.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental management</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ Manage</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">39</style></volume><pages><style face="normal" font="default" size="100%">806-18</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The 4-year drawdown of Horsetooth Reservoir, Colorado, for dam maintenance, provides a case study analog of vegetation response on sediment that might be exposed from removal of a tall dam. Early vegetation recovery on the exposed reservoir bottom was a combination of (1) vegetation colonization on bare, moist substrates typical of riparian zones and reservoir sediment of shallow dams and (2) a shift in moisture status from mesic to the xeric conditions associated with the pre-impoundment upland position of most of the drawdown zone. Plant communities changed rapidly during the first four years of exposure, but were still substantially different from the background upland plant community. Predictions from the recruitment box model about the locations of Populus deltoides subsp. monilifera (plains cottonwood) seedlings relative to the water surface were qualitatively confirmed with respect to optimum locations. However, the extreme vertical range of water surface elevations produced cottonwood seed regeneration well outside the predicted limits of drawdown rate and height above late summer stage. The establishment and survival of cottonwood at high elevations and the differences between the upland plant community and the community that had developed after four years of exposure suggest that vegetation recovery following tall dam removal will follow a trajectory very different from a simple reversal of the response to dam construction, involving not only long time scales of establishment and growth of upland vegetation, but also possibly decades of persistence of legacy vegetation established during the reservoir to upland transition.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17453277?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Coutand, Catherine</style></author><author><style face="normal" font="default" size="100%">Fournier, Meriem</style></author><author><style face="normal" font="default" size="100%">Moulia, Bruno</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The gravitropic response of poplar trunks: key roles of prestressed wood regulation and the relative kinetics of cambial growth versus wood maturation.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">144</style></volume><pages><style face="normal" font="default" size="100%">1166-80</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In tree trunks, the motor of gravitropism involves radial growth and differentiation of reaction wood (Archer, 1986). The first aim of this study was to quantify the kinematics of gravitropic response in young poplar (Populus nigra x Populus deltoides, 'I4551') by measuring the kinematics of curvature fields along trunks. Three phases were identified, including latency, upward curving, and an anticipative autotropic decurving, which has been overlooked in research on trees. The biological and mechanical bases of these processes were investigated by assessing the biomechanical model of Fournier et al. (1994). Its application at two different time spans of integration made it possible to test hypotheses on maturation, separating the effects of radial growth and cross section size from those of wood prestressing. A significant correlation between trunk curvature and Fournier's model integrated over the growing season was found, but only explained 32% of the total variance. Moreover, over a week's time period, the model failed due to a clear out phasing of the kinetics of radial growth and curvature that the model does not take into account. This demonstrates a key role of the relative kinetics of radial growth and the maturation process during gravitropism. Moreover, the degree of maturation strains appears to differ in the tension woods produced during the upward curving and decurving phases. Cell wall maturation seems to be regulated to achieve control over the degree of prestressing of tension wood, providing effective control of trunk shape.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17468227?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Marinari, Sara</style></author><author><style face="normal" font="default" size="100%">Calfapietra, Carlo</style></author><author><style face="normal" font="default" size="100%">Angelis, Paolo de</style></author><author><style face="normal" font="default" size="100%">Mugnozza, Giuseppe Scarascia</style></author><author><style face="normal" font="default" size="100%">Grego, Stefano</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Impact of elevated CO(2) and nitrogen fertilization on foliar elemental composition in a short rotation poplar plantation.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">147</style></volume><pages><style face="normal" font="default" size="100%">507-15</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The experiment was carried out on a short rotation coppice culture of poplars (POP-EUROFACE, Central Italy), growing in a free air carbon dioxide enriched atmosphere (FACE). The specific objective of this work was to study whether elevated CO(2) and fertilization (two CO(2) treatments, elevated CO(2) and control, two N fertilization treatments, fertilized and unfertilized), as well as the interaction between treatments caused an unbalanced nutritional status of leaves in three poplar species (P. x euramericana, P. nigra and P. alba). Finally, we discuss the ecological implications of a possible change in foliar nutrients concentration. CO(2) enrichment reduced foliar nitrogen and increased the concentration of magnesium; whereas nitrogen fertilization had opposite effects on leaf nitrogen and magnesium concentrations. Moreover, the interaction between elevated CO(2) and N fertilization amplified some element unbalances such as the K/N-ratio.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17084005?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhao, Nan</style></author><author><style face="normal" font="default" size="100%">Guan, Ju</style></author><author><style face="normal" font="default" size="100%">Lin, Hong</style></author><author><style face="normal" font="default" size="100%">Chen, Feng</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Molecular cloning and biochemical characterization of indole-3-acetic acid methyltransferase from poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Phytochemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Phytochemistry</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">68</style></volume><pages><style face="normal" font="default" size="100%">1537-44</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Indole-3-acetic acid (IAA) is the most active endogenous auxin and is involved in various physiological processes in higher plants. Concentrations of IAA in plant tissues are regulated at multiple levels including de novo biosynthesis, conjugation/deconjugation, and degradation. In this paper, we report molecular isolation and biochemical characterization of a gene PtIAMT1 from poplar encoding IAA methyltransferase (IAMT), which plays a role in regulating IAA homeostasis. PtIAMT1 was identified from the poplar genome based on sequence similarity to Arabidopsis IAMT. A full-length cDNA of PtIAMT1 was cloned from poplar roots via RT-PCR. Recombinant PtIAMT1 expressed in Escherichia coli was purified to electrophoretic homogeneity. Enzyme assays combined with GC-MS verified that PtIAMT1 catalyzes formation of methyl indole-3-acetate using S-adenosyl-l-methionine (SAM) as a methyl donor and IAA as a methyl acceptor. PtIAMT1 had a temperature optimum at 25 degrees C and a pH optimum at pH 7.5. Its activity was promoted by K(+) but inhibited by Fe(2+), Cu(2+) and Zn(2+). Under steady-state conditions, PtIAMT1 exhibited apparent K(m) values of 23.1 microM and 30.4 microM for IAA and SAM, respectively. Gene expression analysis showed that PtIAMT1 had the highest level of expression in stems, a moderate level of expression in young leaves, and a low level of expression in roots. Presence of PtIAMT1 transcripts in several organs suggests that PtIAMT1 is involved in development of multiple organs in poplar.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17499822?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Percy, K E</style></author><author><style face="normal" font="default" size="100%">Nosal, M</style></author><author><style face="normal" font="default" size="100%">Heilman, W</style></author><author><style face="normal" font="default" size="100%">Dann, T</style></author><author><style face="normal" font="default" size="100%">Sober, J</style></author><author><style face="normal" font="default" size="100%">Legge, A H</style></author><author><style face="normal" font="default" size="100%">Karnosky, D F</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">New exposure-based metric approach for evaluating O(3) risk to North American aspen forests.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">147</style></volume><pages><style face="normal" font="default" size="100%">554-66</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The United States and Canada currently use exposure-based metrics to protect vegetation from O(3). Using 5 years (1999-2003) of co-measured O(3), meteorology and growth response, we have developed exposure-based regression models that predict Populus tremuloides growth change within the North American ambient air quality context. The models comprised growing season fourth-highest daily maximum 8-h average O(3) concentration, growing degree days, and wind speed. They had high statistical significance, high goodness of fit, include 95% confidence intervals for tree growth change, and are simple to use. Averaged across a wide range of clonal sensitivity, historical 2001-2003 growth change over most of the 26 Mha P. tremuloides distribution was estimated to have ranged from no impact (0%) to strong negative impacts (-31%). With four aspen clones responding negatively (one responded positively) to O(3), the growing season fourth-highest daily maximum 8-h average O(3) concentration performed much better than growing season SUM06, AOT40 or maximum 1h average O(3) concentration metrics as a single indicator of aspen stem cross-sectional area growth.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17140714?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Karnosky, David F</style></author><author><style face="normal" font="default" size="100%">Skelly, John M</style></author><author><style face="normal" font="default" size="100%">Percy, Kevin E</style></author><author><style face="normal" font="default" size="100%">Chappelka, Art H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Perspectives regarding 50 years of research on effects of tropospheric ozone air pollution on US forests.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">147</style></volume><pages><style face="normal" font="default" size="100%">489-506</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Tropospheric ozone (O(3)) was first determined to be phytotoxic to grapes in southern California in the 1950s. Investigations followed that showed O(3) to be the cause of foliar symptoms on tobacco and eastern white pine. In the 1960s, &quot;X&quot; disease of ponderosa pines within the San Bernardino Mountains was likewise determined to be due to O(3). Nearly 50 years of research have followed. Foliar O(3) symptoms have been verified under controlled chamber conditions. Studies have demonstrated negative growth effects on forest tree seedlings due to season-long O(3) exposures, but due to complex interactions within forest stands, evidence of similar losses within mature tree canopies remains elusive. Investigations on tree growth, O(3) flux, and stand productivity are being conducted along natural O(3) gradients and in open-air exposure systems to better understand O(3) effects on forest ecosystems. Given projected trends in demographics, economic output and climate, O(3) impacts on US forests will continue and are likely to increase.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17084004?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kelleher, Colin T</style></author><author><style face="normal" font="default" size="100%">Chiu, Readman</style></author><author><style face="normal" font="default" size="100%">Shin, Heesun</style></author><author><style face="normal" font="default" size="100%">Bosdet, Ian E</style></author><author><style face="normal" font="default" size="100%">Krzywinski, Martin I</style></author><author><style face="normal" font="default" size="100%">Fjell, Chris D</style></author><author><style face="normal" font="default" size="100%">Wilkin, Jennifer</style></author><author><style face="normal" font="default" size="100%">Yin, Tongming</style></author><author><style face="normal" font="default" size="100%">Difazio, Stephen P</style></author><author><style face="normal" font="default" size="100%">Ali, Johar</style></author><author><style face="normal" font="default" size="100%">Asano, Jennifer K</style></author><author><style face="normal" font="default" size="100%">Chan, Susanna</style></author><author><style face="normal" font="default" size="100%">Cloutier, Alison</style></author><author><style face="normal" font="default" size="100%">Girn, Noreen</style></author><author><style face="normal" font="default" size="100%">Leach, Stephen</style></author><author><style face="normal" font="default" size="100%">Lee, Darlene</style></author><author><style face="normal" font="default" size="100%">Mathewson, Carrie A</style></author><author><style face="normal" font="default" size="100%">Olson, Teika</style></author><author><style face="normal" font="default" size="100%">O'connor, Katie</style></author><author><style face="normal" font="default" size="100%">Prabhu, Anna-Liisa</style></author><author><style face="normal" font="default" size="100%">Smailus, Duane E</style></author><author><style face="normal" font="default" size="100%">Stott, Jeffery M</style></author><author><style face="normal" font="default" size="100%">Tsai, Miranda</style></author><author><style face="normal" font="default" size="100%">Wye, Natasja H</style></author><author><style face="normal" font="default" size="100%">Yang, George S</style></author><author><style face="normal" font="default" size="100%">Zhuang, Jun</style></author><author><style face="normal" font="default" size="100%">Holt, Robert A</style></author><author><style face="normal" font="default" size="100%">Putnam, Nicholas H</style></author><author><style face="normal" font="default" size="100%">Vrebalov, Julia</style></author><author><style face="normal" font="default" size="100%">Giovannoni, James J</style></author><author><style face="normal" font="default" size="100%">Grimwood, Jane</style></author><author><style face="normal" font="default" size="100%">Schmutz, Jeremy</style></author><author><style face="normal" font="default" size="100%">Rokhsar, Daniel</style></author><author><style face="normal" font="default" size="100%">Jones, Steven J M</style></author><author><style face="normal" font="default" size="100%">Marra, Marco A</style></author><author><style face="normal" font="default" size="100%">Tuskan, Gerald A</style></author><author><style face="normal" font="default" size="100%">Bohlmann, Jörg</style></author><author><style face="normal" font="default" size="100%">Ellis, Brian E</style></author><author><style face="normal" font="default" size="100%">Ritland, Kermit</style></author><author><style face="normal" font="default" size="100%">Douglas, Carl J</style></author><author><style face="normal" font="default" size="100%">Schein, Jacqueline E</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A physical map of the highly heterozygous Populus genome: integration with the genome sequence and genetic map and analysis of haplotype variation.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">50</style></volume><pages><style face="normal" font="default" size="100%">1063-78</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">As part of a larger project to sequence the Populus genome and generate genomic resources for this emerging model tree, we constructed a physical map of the Populus genome, representing one of the few such maps of an undomesticated, highly heterozygous plant species. The physical map, consisting of 2802 contigs, was constructed from fingerprinted bacterial artificial chromosome (BAC) clones. The map represents approximately 9.4-fold coverage of the Populus genome, which has been estimated from the genome sequence assembly to be 485 +/- 10 Mb in size. BAC ends were sequenced to assist long-range assembly of whole-genome shotgun sequence scaffolds and to anchor the physical map to the genome sequence. Simple sequence repeat-based markers were derived from the end sequences and used to initiate integration of the BAC and genetic maps. A total of 2411 physical map contigs, representing 97% of all clones assigned to contigs, were aligned to the sequence assembly (JGI Populus trichocarpa, version 1.0). These alignments represent a total coverage of 384 Mb (79%) of the entire poplar sequence assembly and 295 Mb (96%) of linkage group sequence assemblies. A striking result of the physical map contig alignments to the sequence assembly was the co-localization of multiple contigs across numerous regions of the 19 linkage groups. Targeted sequencing of BAC clones and genetic analysis in a small number of representative regions showed that these co-aligning contigs represent distinct haplotypes in the heterozygous individual sequenced, and revealed the nature of these haplotype sequence differences.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17488239?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lei, Yanbao</style></author><author><style face="normal" font="default" size="100%">Korpelainen, Helena</style></author><author><style face="normal" font="default" size="100%">Li, Chunyang</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Physiological and biochemical responses to high Mn concentrations in two contrasting Populus cathayana populations.</style></title><secondary-title><style face="normal" font="default" size="100%">Chemosphere</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Chemosphere</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">68</style></volume><pages><style face="normal" font="default" size="100%">686-94</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We exposed the cuttings of Populus cathayana to Hoagland's solution containing four different manganese (Mn) concentrations (0, 0.1, 0.5 and 1mM) in a greenhouse to characterize the physiological and biochemical basis of Mn resistance in woody plants. Two contrasting populations of P. cathayana were used in our study, which were from the wet and dry climate regions in western China, respectively. The results showed that Mn treatments significantly decreased chlorophyll content and growth characteristics, including shoot height, basal diameter, biomass accumulation and total leaf area in the two populations. Mn treatments also significantly increased the levels of abscisic acid (ABA), polyamines and free amino acids especially proline (Pro), histidine (His) and phenylalanine (Phe) available for cellular signaling and heavy metal chelation. In addition, high Mn concentrations also caused oxidative stress indicated as the accumulation of hydrogen peroxide (H(2)O(2)) and malondialdehyde (MDA) contents. On the other hand, there were different responses to Mn stress between the two contrasting populations. Compared with the dry climate population, the wet climate population accumulated more Mn in plant tissues especially in leaves; it showed lower tolerance index and more pronounced decrease in growth and chlorophyll contents. The wet climate population not only accumulated less ABA, putrescine and free amino acids, but also exhibited lower activities of superoxide dismutase (SOD) and ascorbate peroxidase (APX), thus suffering from more serious oxidative damage. Therefore, our results showed that the wet climate population was more susceptible to Mn stress than the dry climate population.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17346769?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Cusack, Brian P</style></author><author><style face="normal" font="default" size="100%">Wolfe, Kenneth H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">When gene marriages don't work out: divorce by subfunctionalization.</style></title><secondary-title><style face="normal" font="default" size="100%">Trends in genetics : TIG</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Trends Genet.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">23</style></volume><pages><style face="normal" font="default" size="100%">270-2</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We describe how a bifunctional gene, encoding two proteins by alternative splicing, arose when the chloroplast gene RPL32 integrated into an intron of the nuclear gene SODcp in an ancestor of mangrove and poplar trees. Mangrove retains the alternatively spliced chimeric gene, but in poplar it underwent duplication and complete subfunctionalization, through complementary structural degeneration, to re-form separate RPL32 and SODcp genes.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17418444?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Nishikubo, Nobuyuki</style></author><author><style face="normal" font="default" size="100%">Awano, Tatsuya</style></author><author><style face="normal" font="default" size="100%">Banasiak, Alicja</style></author><author><style face="normal" font="default" size="100%">Bourquin, Veronica</style></author><author><style face="normal" font="default" size="100%">Ibatullin, Farid</style></author><author><style face="normal" font="default" size="100%">Funada, Ryo</style></author><author><style face="normal" font="default" size="100%">Brumer, Harry</style></author><author><style face="normal" font="default" size="100%">Teeri, Tuula T</style></author><author><style face="normal" font="default" size="100%">Hayashi, Takahisa</style></author><author><style face="normal" font="default" size="100%">Sundberg, Björn</style></author><author><style face="normal" font="default" size="100%">Mellerowicz, Ewa J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Xyloglucan endo-transglycosylase (XET) functions in gelatinous layers of tension wood fibers in poplar--a glimpse into the mechanism of the balancing act of trees.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant &amp; cell physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">48</style></volume><pages><style face="normal" font="default" size="100%">843-55</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Tension wood is a specialized tissue of deciduous trees that functions in bending woody stems to optimize their position in space. Tension wood fibers that develop on one side of the stem have an increased potency to shrink compared with fibers on the opposite side, thus creating a bending moment. It is believed that the gelatinous (G) cell wall layer containing almost pure cellulose of tension wood fibers is pivotal to their shrinking. By analyzing saccharide composition and linkage in isolated G-layers of poplar, we found that they contain some matrix components in addition to cellulose, of which xyloglucan is the most abundant. Xyloglucan, xyloglucan endo-transglycosylase (XET) activity and xyloglucan endo-transglycosylase/hydrolase (XTH) gene products were detected in developing G-layers by labeling using CCRC-M1 monoclonal antibody, in situ incorporation of XXXG-SR and the polyclonal antibody to poplar PttXET16-34, respectively, indicating that xyloglucan is incorporated into the G-layer during its development. Moreover, several XTH transcripts were altered and were generally up-regulated in developing tension wood compared with normal wood. In mature G-fibers, XTH gene products were detected in the G-layers while the XET activity was evident in the adjacent S(2) wall layer. We propose that XET activity is essential for G-fiber shrinking by repairing xyloglucan cross-links between G- and S(2)-layers and thus maintaining their contact. Surprisingly, XTH gene products and XET activity persisted in mature G-fibers for several years, suggesting that the enzyme functions after cell death repairing the cross-links as they are being broken during the shrinking process.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17504814?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">An, Hui</style></author><author><style face="normal" font="default" size="100%">Shangguan, Zhou-ping</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Photosynthetic characteristics of dominant plant species at different succession stages of vegetation on Loess Plateau].</style></title><secondary-title><style face="normal" font="default" size="100%">Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ying Yong Sheng Tai Xue Bao</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">18</style></volume><pages><style face="normal" font="default" size="100%">1175-80</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">According to the succession sequence of vegetation on Ziwuling of Loess Plateau, the dominant species at different secondary succession stages, i. e., Bothriochloa ischaemum, Artemisia gmelinii, Hippophae rhamnoides, Sophara viciifolia, Populus davidiana and Quercus liaotungensis, were selected to measure the total N contents in their leaves and soil, and the parameters of leaf gas exchange, chlorophyll content and chlorophyll fluorescence. The results showed that with the succession of vegetation, the total N content in 0-20 cm soil layer had an increasing trend, while the leaf total N and chlorophyll contents were increased first but decreased then. The leaf total N content of dominant species at shrub community stage (H. rhamnoides and S. viciifolia) was significantly higher (P &lt; 0.05) than that at other succession stages, and the photosynthetic rate (P(n)) was higher at the stages of herbaceous and shrub communities than at the early and climax stages of forest community. Stomatal conductance (g(s)) and P(n) had the similar variation trends. The dominant species at the stages of herbaceous and shrub communities had a higher transpiration rate (T(r)), while those at the climax stage of forest community had the lowest one. With vegetation succession, the maximum photochemical efficiency (F(v)/F(m)) had a slow increase, while the actual photochemical efficiency of PS II (Phi(PSII)) was increased first but decreased then. Along the succession sequence, photochemical quenching coefficient (q(P)) presented an increasing trend, while non-photochemical quenching coefficient (q(NP)) showed a single-peaked curve. Therefore, the ecophysiological attributes and adaptation to microhabitats of early succession plant are different from the late succession plants.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17763712?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zalesny, Ronald S</style></author><author><style face="normal" font="default" size="100%">Bauer, Edmund O</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Evaluation of Populus and Salix continuously irrigated with landfill leachate I. Genotype-specific elemental phytoremediation.</style></title><secondary-title><style face="normal" font="default" size="100%">International journal of phytoremediation</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Int J Phytoremediation</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jul-Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">281-306</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">There is a need for the identification and selection of specific tree genotypes that can sequester elements from contaminated soils, with elevated rates of uptake. We irrigated Populus (DN17, DN182, DN34, NM2, NM6) and Salix (94003, 94012, S287, S566, SX61) genotypes planted in large soil-filled containers with landfill leachate or municipal water and tested for differences in inorganic element concentrations (P, K, Ca, Mg, S, Zn, B, Mn, Fe, Cu, Al, Na, and Cl) in the leaves, stems, and roots. Trees were irrigated with leachate or water during the final 12 wk of the 18-wk study. Genotype-specific uptake existed. For genera, tissue concentrations exhibited four responses. First, Populus had the greatest uptake of P, K, S, Cu, and Cl. Second, Salix exhibited the greatest uptake of Zn, B, Fe, and Al. Third, Salix had greater concentrations of Ca and Mg in leaves, while Populus had greater concentrations in stems and roots. Fourth, Populus had greater concentrations of Mn and Na in leaves and stems, while Salix had greater concentrations in roots. Populus deltoides x P. nigra clones exhibited better overall phytoremediation than the P. nigra x P. maximowiczii genotypes tested. Phytoremediation for S. purpurea clones 94003 and 94012 was generally less than for other Salix genotypes. Overall, concentrations of elements in the leaves, stems, and roots corroborated those in the plant-sciences literature. Uptake was dependent upon the specific genotype for most elements. Our results corroborated the need for further testing and selecting of specific clones for various phytoremediation needs, while providing a baseline for future researchers developing additional studies and resource managers conducting on-site remediation.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18246707?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zalesny, Ronald S</style></author><author><style face="normal" font="default" size="100%">Bauer, Edmund O</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Evaluation of Populus and Salix continuously irrigated with landfill leachate II. soils and early tree development.</style></title><secondary-title><style face="normal" font="default" size="100%">International journal of phytoremediation</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Int J Phytoremediation</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jul-Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">307-23</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Soil contaminant levels and early tree growth data are helpful for assessing phytoremediation systems. Populus (DN17, DN182, DN34, NM2, and NM6) and Salix (94003, 94012, S287, S566, and SX61) genotypes were irrigated with landfill leachate or municipal water and tested for differences in (1) element concentrations (P, K, Ca, Mg, S, Zn, B, Mn, Fe, Cu, Al, and Na) of a topsoil layer and a layer of sand in tanks with a cover crop of trees or no trees and (2) height, diameter, volume, and dry mass of leaves, stems, and roots. Trees were irrigated with leachate or water during the final 12 wk of the 18-wk study. Differences in most soil element concentrations were negligible (P &gt; 0.05) for irrigation treatments and cover main effects. Phosphorous, K, Mg, S, Zn, Mn, Fe, and Al concentrations were greater in topsoil than sand (P = 0.0011 for Mg; P &lt; 0.0001 for others). There was broad variation between genera and among clones for all growth traits. The treatment x clone interaction governed height, volume, and root dry mass, with (94012, SX61), (NM2, S566, SX61), and (S287, S566) exhibiting the greatest levels, respectively,following leachate application. Given the broad amount of variability among and within these genera, there is great potential for the identification and selection of specific genotypes with a combination of elevated phytoremediation capabilities and tree yield. From a practical standpoint, these results may be used as a baseline for the development of future remediation systems.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18246708?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gunderson, J J</style></author><author><style face="normal" font="default" size="100%">Knight, J D</style></author><author><style face="normal" font="default" size="100%">Van Rees, K C J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Impact of ectomycorrhizal colonization of hybrid poplar on the remediation of diesel-contaminated soil.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of environmental quality</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Environ. Qual.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jul-Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">36</style></volume><pages><style face="normal" font="default" size="100%">927-34</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Infection by ectomycorrhizal (ECM) fungi may benefit hybrid poplar growing in contaminated soils by providing greater access to water and nutrients and possibly protecting the trees from direct contact with toxic contaminants. The objective of this research was to determine the effect of colonization of the ECM fungus Pisolithus tinctorius (Pers.) Coker &amp; Couch on hybrid poplar fine root production, biomass and N and P uptake when grown in diesel-contaminated soil (5000 mg diesel fuel kg soil(-1)). Commercially available Mycogrow Tree Tabs were the source of inoculum. A minirhizotron camera was used to provide the data necessary for estimating fine root production. Colonization of hybrid poplar roots (P. deltoides x [P. laurifolia x P. nigra] cv. Walker) by P. tinctorius increased total fine root production in diesel-contaminated soil to 56.58 g m(-2) compared to 22.59 g m(-2) in the uncolonized, diesel-contaminated treatment. Hybrid poplar leaf N and P concentrations were significantly greater in the diesel-contaminated/ECM-colonized treatment compared to the diesel-contaminated/uncolonized treatment after 12 wk, while significantly less diesel fuel was recovered from the soil of the uncolonized treatment compared to the colonized treatment. Both planted treatments removed more contaminants from the soil than an unplanted control. Significantly greater concentrations of total petroleum hydrocarbons (TPH) were found sequestered in hybrid poplar root/fungal-sheath complexes from the colonized treatment compared to the roots of the uncolonized treatment. The results of this study indicate that over a 12-wk growth period, ECM colonization of hybrid poplar in diesel-contaminated soils increased fine root production and whole-plant biomass, but inhibited removal of TPH from the soil.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17526871?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Morell, Virginia</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Ecology. Aspens return to Yellowstone, with help from some wolves.</style></title><secondary-title><style face="normal" font="default" size="100%">Science (New York, N.Y.)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Science</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jul 27</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">317</style></volume><pages><style face="normal" font="default" size="100%">438-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">5837</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17656692?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Koh, Cha San</style></author><author><style face="normal" font="default" size="100%">Didierjean, Claude</style></author><author><style face="normal" font="default" size="100%">Navrot, Nicolas</style></author><author><style face="normal" font="default" size="100%">Panjikar, Santosh</style></author><author><style face="normal" font="default" size="100%">Mulliert, Guillermo</style></author><author><style face="normal" font="default" size="100%">Rouhier, Nicolas</style></author><author><style face="normal" font="default" size="100%">Jacquot, Jean-Pierre</style></author><author><style face="normal" font="default" size="100%">Aubry, André</style></author><author><style face="normal" font="default" size="100%">Shawkataly, Omar</style></author><author><style face="normal" font="default" size="100%">Corbier, Catherine</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Crystal structures of a poplar thioredoxin peroxidase that exhibits the structure of glutathione peroxidases: insights into redox-driven conformational changes.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Mol. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jul 13</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">370</style></volume><pages><style face="normal" font="default" size="100%">512-29</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Glutathione peroxidases (GPXs) are a group of enzymes that regulate the levels of reactive oxygen species in cells and tissues, and protect them against oxidative damage. Contrary to most of their counterparts in animal cells, the higher plant GPX homologues identified so far possess cysteine instead of selenocysteine in their active site. Interestingly, the plant GPXs are not dependent on glutathione but rather on thioredoxin as their in vitro electron donor. We have determined the crystal structures of the reduced and oxidized form of Populus trichocarpaxdeltoides GPX5 (PtGPX5), using a selenomethionine derivative. PtGPX5 exhibits an overall structure similar to that of the known animal GPXs. PtGPX5 crystallized in the assumed physiological dimeric form, displaying a pseudo ten-stranded beta sheet core. Comparison of both redox structures indicates that a drastic conformational change is necessary to bring the two distant cysteine residues together to form an intramolecular disulfide bond. In addition, a computer model of a complex of PtGPX5 and its in vitro recycling partner thioredoxin h1 is proposed on the basis of the crystal packing of the oxidized form enzyme. A possible role of PtGPX5 as a heavy-metal sink is also discussed.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17531267?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bladon, Kevin D</style></author><author><style face="normal" font="default" size="100%">Silins, Uldis</style></author><author><style face="normal" font="default" size="100%">Landhäusser, Simon M</style></author><author><style face="normal" font="default" size="100%">Messier, Christian</style></author><author><style face="normal" font="default" size="100%">Lieffers, Victor J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Carbon isotope discrimination and water stress in trembling aspen following variable retention harvesting.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">27</style></volume><pages><style face="normal" font="default" size="100%">1065-71</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Variable retention harvesting (VRH) has been proposed as a silvicultural practice to maintain biodiversity and ecosystem integrity. No previous study has examined tree carbon isotope discrimination to provide insights into water stress that could lead to dieback and mortality of trees following VRH. We measured and compared the carbon isotope ratios (delta(13)C) in stem wood of trembling aspen (Populus tremuloides Michx.) before and after VRH. Eight trees were sampled from isolated residual, edge and control (interior of unharvested stand) positions from each of seven plots in three regions (Calling Lake and Drayton Valley, Alberta and Lac Duparquet, Québec). After VRH, the general trend in mean delta(13)C was residual &gt; edge &gt; control trees. Although this trend is indicative of water stress in residual trees, it also suggests that edge trees received some sheltering effect, reducing their stress compared with that of residuals. A strong inverse relationship was found between the delta(13)C values and the mean annual precipitation in each region. The trend in mean delta(13)C signature was Calling Lake &gt; Drayton Valley &gt; Lac Duparquet trees. These results suggest that residual or edge trees in drier regions are more likely to suffer water stress following VRH. We also observed a trend of greater delta(13)C in stout trees compared with slender trees, both before and after VRH. The evidence of greater water stress in stout trees likely occurred because of a positive relationship between stem diameter and crown volume per basal area. Our results provide evidence that water stress could be the driving mechanism leading to dieback and mortality of residual trees shortly after VRH. Additionally, the results from edge trees indicate that leaving hardwood residuals in larger patches or more sheltered landscape positions could reduce the water stress to which these trees are subjected, thereby reducing dieback and mortality.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17403660?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhang, Yanmei</style></author><author><style face="normal" font="default" size="100%">Zhang, Xinye</style></author><author><style face="normal" font="default" size="100%">Chen, Yuchen</style></author><author><style face="normal" font="default" size="100%">Wang, Qi</style></author><author><style face="normal" font="default" size="100%">Wang, Mingxiu</style></author><author><style face="normal" font="default" size="100%">Huang, Minren</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Function and chromosomal localization of differentially expressed genes induced by Marssonina brunnea f. sp. multigermtubi in Populus deltoides.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of genetics and genomics = Yi chuan xue bao</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J Genet Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">34</style></volume><pages><style face="normal" font="default" size="100%">641-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A total of 1,160 differentially expressed genes induced by Marssonina brunnea f. sp. multigermtubi were identified in Populus deltoides cv. 'Lux' (I-69/55) with two-colour cDNA microarray including 2,952 cDNAs from two cDNA libraries constructed with 72 h inoculated poplar leaves. Functional analysis showed that 1,160 genes were classified into 11 functional categories that are involved in metabolism (15.9%), signal transduction (9.5%), transcription and replication (8.7%), and cell rescue and defense (7.8%). Among them, 926 genes were sporadically localized on 19 linkage groups. Chromosome 2 contained 102 (11%) differentially expressed genes, followed by chromosome 1 which contains 93 genes (10%), and chromosome 17 had the least number of differentially expressed genes. Clustering of expressed sequence tags (ESTs) in poplar genome was observed at the terminal regions of several chromosomes. The relationship between cluster of genes and plant defense response would be further studied.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17643950?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Dos Santos Utmazian, Maria Noel</style></author><author><style face="normal" font="default" size="100%">Wieshammer, Gerlinde</style></author><author><style face="normal" font="default" size="100%">Vega, Rosa</style></author><author><style face="normal" font="default" size="100%">Wenzel, Walter W</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Hydroponic screening for metal resistance and accumulation of cadmium and zinc in twenty clones of willows and poplars.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">148</style></volume><pages><style face="normal" font="default" size="100%">155-65</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We screened 20 different clones of willow and poplar species in hydroponic experiments for their metal resistance and accumulation properties. Plants were exposed for 4 weeks either to single additions of (microM) 4.45 Cd or 76.5 Zn, or a metal cocktail containing the same amounts of Cd and Zn along with 7.87 Cu and 24.1 Pb. Plant biomass, metal tolerance and metal accumulation pattern in roots and leaves varied greatly between clones. The leaf:root ratio of metal concentrations was clearly underestimated compared to soil experiments. The largest metal concentrations in leaves were detected in Salix dasyclados (315 mg Cdkg(-1) d.m.) and a Salix smithiana clone (3180 mg Znkg(-1) d.m.) but these species showed low metal tolerance. In spite of smaller Cd and Zn concentrations, the metal-tolerant clones Salix matsudana, Salix fragilis-1, and Salix purpurea-1 hold promise for phytoextraction as they produced large biomass and metal contents in leaves.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17241723?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rizzo, Milena</style></author><author><style face="normal" font="default" size="100%">Bernardi, Rodolfo</style></author><author><style face="normal" font="default" size="100%">Salvini, Mariangela</style></author><author><style face="normal" font="default" size="100%">Nali, Cristina</style></author><author><style face="normal" font="default" size="100%">Lorenzini, Giacomo</style></author><author><style face="normal" font="default" size="100%">Durante, Mauro</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Identification of differentially expressed genes induced by ozone stress in sensitive and tolerant poplar hybrids.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">164</style></volume><pages><style face="normal" font="default" size="100%">945-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The differential expression of genes induced by an acute ozone treatment was analysed in two poplar clones, i.e. Populus deltoides x maximowiczii, Eridano clone, and Populus x euoramericana, I-214 clone, respectively, sensitive and tolerant to this pollutant, performing suppression subtractive hybridization (SSH). From the obtained cDNA libraries several clones were obtained, which corresponded to differentially regulated genes. Preliminary expression analyses of four genes, Fs23A-LRP, Ft33B-CaBP, Ft312B-WRKY, and Ft32C-WAK identified by the primary screening, were conducted by semi-quantitative RT-PCR to evaluate the ozone responsiveness of the libraries. The most interesting finding is the co-activation of a wall associated kinase and a WRKY transcription factor in response to O(3) stress.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17081654?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ehlting, B</style></author><author><style face="normal" font="default" size="100%">Dluzniewska, P</style></author><author><style face="normal" font="default" size="100%">Dietrich, H</style></author><author><style face="normal" font="default" size="100%">Selle, A</style></author><author><style face="normal" font="default" size="100%">Teuber, M</style></author><author><style face="normal" font="default" size="100%">Hänsch, R</style></author><author><style face="normal" font="default" size="100%">Nehls, U</style></author><author><style face="normal" font="default" size="100%">Polle, A</style></author><author><style face="normal" font="default" size="100%">Schnitzler, J-P</style></author><author><style face="normal" font="default" size="100%">Rennenberg, H</style></author><author><style face="normal" font="default" size="100%">Gessler, A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Interaction of nitrogen nutrition and salinity in Grey poplar (Populus tremula x alba).</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">30</style></volume><pages><style face="normal" font="default" size="100%">796-811</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Salinity represents an increasing environmental problem in managed ecosystems. Populus spp. is widely used for wood production by short-rotation forestry in fertilized plantations and can be grown on saline soil. Because N fertilization plays an important role in salt tolerance, we analysed Grey poplar (Populus tremula x alba, syn. Populus canescens) grown with either 1 mM nitrate or ammonium subjected to moderate 75 mM NaCl. The impact of N nutrition on amelioration of salt tolerance was analysed on different levels of N metabolism such as N uptake, assimilation and N (total N, proteins and amino compounds) accumulation. Na concentration increased in all tissues over time of salt exposure. The N nutrition-dependent effects of salt exposure were more intensive in roots than in leaves. Application of salt reduced root increment as well as stem height increase and, at the same time, increased the concentration of total amino compounds more intensively in roots of ammonium-fed plants. In leaves, salt treatment increased concentrations of total N more intensively in nitrate-fed plants and concentrations of amino compounds independently of N nutrition. The major changes in N metabolism of Grey poplar exposed to moderate salt concentrations were detected in the significant increase of amino acid concentrations. The present results indicate that N metabolism of Grey poplar exposed to salt performed better when the plants were fed with nitrate instead of ammonium as sole N source. Therefore, nitrate fertilization of poplar plantations grown on saline soil should be preferred.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17547652?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhang, Feng</style></author><author><style face="normal" font="default" size="100%">Wang, Yuping</style></author><author><style face="normal" font="default" size="100%">Yang, Yingli</style></author><author><style face="normal" font="default" size="100%">Wu, Hao</style></author><author><style face="normal" font="default" size="100%">Wang, Di</style></author><author><style face="normal" font="default" size="100%">Liu, Jianquan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Involvement of hydrogen peroxide and nitric oxide in salt resistance in the calluses from Populus euphratica.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">30</style></volume><pages><style face="normal" font="default" size="100%">775-85</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Nitric oxide (NO) and hydrogen peroxide (H2O2) function as signalling molecules in plants under abiotic and biotic stresses. Calluses from Populus euphratica, which show salt tolerance, were used to study the interaction of NO and H2O2 in plant adaptation to salt resistance. The nitric oxide synthase (NOS) activity was identified in the calluses, and this activity was induced under 150 mM NaCl treatment. Under 150 mM NaCl treatment, the sodium (Na) percentage decreased, but the potassium (K) percentage and the K/Na ratio increased in P. euphratica calluses. Application of glucose/glucose oxidase (G/GO, a H2O2 donor) and sodium nitroprusside (SNP, a NO donor) revealed that both H2O2 and NO resulted in increased K/Na ratio in a concentration-dependent manner. Diphenylene iodonium (DPI, an NADPH oxidase inhibitor) counteracted H2O2 and NO effect by increasing the Na percentage, decreasing the K percentage and K/Na ratio. NG-monomethyl-L-Arg monoacetate (NMMA, an NO synthase inhibitor) and 2-phenyl-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxyde (PTIO, a specific NO scavenger) only reversed NO effect, but did not block H2O2 effect. The increased activity of plasma membrane (PM) H+ -ATPase caused by salt stress was reversed by treatment with DPI and NMMA. Exogenous H2O2 increased the activity of PM H+ -ATPase, but the effect could not be diminished by NMMA and PTIO. The NO-induced increase of PM H+ -ATPase can be reversed by NMMA and PTIO, but not by DPI. Western blot analysis demonstrated that NO and H2O2 stimulated the expression of PM H+ -ATPase in P. euphratica calluses. These results indicate that NO and H2O2 served as intermediate molecules in inducing salt resistance in the calluses from P. euphratica under slat stress by increasing the K/Na ratio, which was dependent on the increased PM H+ -ATPase activity.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17547650?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kashian, Daniel M</style></author><author><style face="normal" font="default" size="100%">Romme, William H</style></author><author><style face="normal" font="default" size="100%">Regan, Claudia M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Reconciling divergent interpretations of quaking aspen decline on the northern Colorado Front Range.</style></title><secondary-title><style face="normal" font="default" size="100%">Ecological applications : a publication of the Ecological Society of America</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ecol Appl</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">17</style></volume><pages><style face="normal" font="default" size="100%">1296-311</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Ecologists have debated over the past 65 years whether quaking aspen (Populus tremuloides Michx.) has or has not declined in abundance, vigor, or regeneration in western North America. Many studies have provided divergent interpretations of the condition of aspen forests, leading to difficulty in translating this ecological information into management recommendations. To reconcile these contrasting conclusions and to test the hypothesis that multiple types of aspen decline and persistence occur simultaneously on heterogeneous landscapes, we assessed 91 aspen stands across the northern Colorado Front Range to determine the range of ecological conditions that underlie aspen decline or persistence. Approximately 15% of aspen forest area in our sample exhibited dieback of mature stems coupled with a lack of young trees indicative of declining stands, most often at lower elevations where elk browsing is heavy and chronic, and where effects of fire exclusion have been most significant. However, 52% of the area sampled had multiple cohorts indicative of self-replacing or persistent stands. Conifer dominance was increasing in over 33% of all aspen forest area sampled, most often at high elevations among lodgepole pine (Pinus contorta var. latifolia Englem. ex Wats.) forests. Reconstructions of relative basal area and density of aspen and lodgepole pine in these stands suggest cyclical dominance of these species, where conifers gradually replace aspen over long fire intervals, and aspen vigorously re-establish following stand-replacing fires. The diversity of ecological contexts across the northern Colorado Front Range creates a variety of aspen dynamics leading to decline or persistence, and no single trend describes the general condition of aspen forests in appropriate detail for managers. Active management may be useful in preserving individual stands at fine scales, but management prescriptions should reflect specific drivers of decline in these stands.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17708209?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Arend, Matthias</style></author><author><style face="normal" font="default" size="100%">Fromm, Jörg</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Seasonal change in the drought response of wood cell development in poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">27</style></volume><pages><style face="normal" font="default" size="100%">985-92</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Field-grown poplar trees (Populus nigra L. x P. maximowiczii Henry, clone Kamabuchi) were exposed to severe drought twice during the growing season to evaluate the impact on wood cell development. The drought treatment caused a reduction in leaf water potential, leaf wilting and a decreased concentration of osmotically active solutes in the cambial zone. Drought-induced changes in the anatomy of developing xylem cells were examined in stem sections and macerated wood samples. In early summer, drought significantly reduced the length and cross-sectional area of newly formed fibers, whereas no such effects were observed in late summer. In well-watered trees, fiber cross-sectional area declined between early and late summer. Similarly, drought reduced the cross-sectional area of vessel elements in early summer but not in late summer, whereas in both control and drought-treated trees, the cross-sectional area of vessel elements decreased between early and late summer. The vessel area to xylem area ratio was unaffected by drought because the drought-induced decrease in vessel size was matched by an increase in the number of newly formed vessel cells. In contrast to its effect in early summer, late-summer drought had no significant effect on fiber and vessel cell development, indicating that sensitivity of wood cell development to drought varies seasonally.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17403651?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Miranda, Manoela</style></author><author><style face="normal" font="default" size="100%">Ralph, Steven G</style></author><author><style face="normal" font="default" size="100%">Mellway, Robin</style></author><author><style face="normal" font="default" size="100%">White, Rick</style></author><author><style face="normal" font="default" size="100%">Heath, Michele C</style></author><author><style face="normal" font="default" size="100%">Bohlmann, Jörg</style></author><author><style face="normal" font="default" size="100%">Constabel, C Peter</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The transcriptional response of hybrid poplar (Populus trichocarpa x P. deltoides) to infection by Melampsora medusae leaf rust involves induction of flavonoid pathway genes leading to the accumulation of proanthocyanidins.</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular plant-microbe interactions : MPMI</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Plant Microbe Interact.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">20</style></volume><pages><style face="normal" font="default" size="100%">816-31</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The transcriptional response of hybrid poplar (Populus trichocarpa x P. deltoides) to poplar leaf rust (Melampsora medusae) infection was studied using the Populus 15.5K cDNA microarray. Pronounced changes in the transcriptome were observed, with approximately 20% of genes on the array showing either induction or repression of transcription within the 9-day infection timecourse. A small number of pathogen-defense genes encoding PR-1, chitinases, and other pathogenesis-related proteins were consistently upregulated throughout the experimental period, but most genes were affected only at individual timepoints. The largest number of changes in gene expression was observed late in the infection at 6 to 9 days postinoculation (dpi). At these timepoints, genes encoding enzymes required for proanthocyanidin (condensed tannin) synthesis were upregulated dramatically. Phytochemical analysis confirmed that, late in the infection, proanthocyanidin levels increased in infected leaves. Strongly M. medusae-repressed genes at 9 dpi included previously characterized wound- and herbivore-induced defense genes, which suggests antagonism between the tree responses to insect feeding and M. medusae infection. In this highly compatible plant-pathogen interaction, we postulate that the biotrophic pathogen evades detection and suppresses early host responses.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17601169?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Tanaka, Sachiyo</style></author><author><style face="normal" font="default" size="100%">Brentner, Laura B</style></author><author><style face="normal" font="default" size="100%">Merchie, Kate M</style></author><author><style face="normal" font="default" size="100%">Schnoor, Jerald L</style></author><author><style face="normal" font="default" size="100%">Yoon, Jong Moon</style></author><author><style face="normal" font="default" size="100%">Van Aken, Benoit</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Analysis of gene expression in poplar trees (Populus deltoides x nigra, DN34) exposed to the toxic explosive hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX).</style></title><secondary-title><style face="normal" font="default" size="100%">International journal of phytoremediation</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Int J Phytoremediation</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jan-Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">15-30</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Poplar plants (Populus deltoides x nigra, DN34) growing under hydroponic conditions were exposed to 50 mg L(-1) of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) for 24 h. The expression of genes potentially involved in the metabolism of toxic explosives was analyzed by reverse-transcriptase (RT) real-time PCR. Genes under study were selected by reference to corresponding genes that were previously shown to be upregulated in the model plant Arabidopsis thaliana by exposure to 2,4,6-trinitrotoluene (TNT) (Ekman et al., 2003. Plant Physiol., 133, 1397-1406). The target genes investigated include several genes encoding for enzymes known to be involved in the detoxification of xenobiotic pollutants, such as glutathione S-transferases (GSTs), cytochrome P-450s (CYPs), NADPH-dependent reductases, and peroxidases. Starting from A. thaliana TNT-inducible genes, corresponding Populus sequences were retrieved from the JGI Poplar Genome Project database and were used to design gene-specific primers. 18S ribosomal DNA (rDNA) was used as an internal standard and recorded gene expression levels were normalized by reference to nonexposed plants. In three separate experiments, five genes were found to be significantly amplified in leaf tissues by exposure to RDX, including GST (9.7 fold), CYP (1.6 fold), reductases (1.6-1.7 fold), and peroxidase (1.7 fold). In root tissues, only a single GST gene was found to be significantly amplified by exposure to RDX (2.0 fold). These results show, for the first time, that the exposure of poplar plants to RDX results in the induction of several genes that are potentially involved in explosive detoxification.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18246712?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Mozŭraitis, Raimondas</style></author><author><style face="normal" font="default" size="100%">Karalius, Vidmantas</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Identification of minor sex pheromone components of the poplar clearwing moth Paranthrene tabaniformis (Lepidoptera, Sesiidae).</style></title><secondary-title><style face="normal" font="default" size="100%">Zeitschrift für Naturforschung. C, Journal of biosciences</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Z. Naturforsch., C, J. Biosci.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jan-Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">62</style></volume><pages><style face="normal" font="default" size="100%">138-42</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A chemical analysis of the crude sex pheromone gland extracts of virgin calling Paranthrene tabaniformis females, obtained from the European part of Kazakhstan, revealed the presence of five compounds: (3E,13Z)-octadeca-3,13-dien-1-ol (E3,Z13-18:OH), (3Z,13Z)-octadeca-3,13-dien-1-ol (Z3,Z13-18:OH), (2E,13Z)-octadeca-2,13-dien-1-ol (E2,Z13-18:OH), (13Z)-octadec-13-en-1-ol (Z13-18:OH), and octadecan-1-ol (18:OH) at the ratios 64.0:32.4: 1.4:0.9:1.3, which are structurally related to sex pheromone components of clearwing moths. Our previous field tests showed synergistic effects of Z3,Z13-18:OH and E2,Z13-18:OH to attract P. tabaniformis males, when these compounds were tested in binary mixtures with the known sex pheromone E3,Z13-18:OH. The three dienic alcohols should all be considered as sex pheromone components of the P. tabaniformis species, while the role of Z13-18:OH and 18:OH remained unclear.</style></abstract><issue><style face="normal" font="default" size="100%">1-2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17425119?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Adelmann, Juliana</style></author><author><style face="normal" font="default" size="100%">Passos, Mauricio</style></author><author><style face="normal" font="default" size="100%">Breyer, Daniel Henrique</style></author><author><style face="normal" font="default" size="100%">dos Santos, Maria Helena Rocha</style></author><author><style face="normal" font="default" size="100%">Lenz, Cesar</style></author><author><style face="normal" font="default" size="100%">Leite, Natalício Ferreira</style></author><author><style face="normal" font="default" size="100%">Lanças, Fernando Mauro</style></author><author><style face="normal" font="default" size="100%">Fontana, José Domingos</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Exotic flora dependence of an unusual Brazilian propolis: the pinocembrin biomarker by capillary techniques.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of pharmaceutical and biomedical analysis</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J Pharm Biomed Anal</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jan 4</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">43</style></volume><pages><style face="normal" font="default" size="100%">174-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Significant amounts of pinocembrin (&gt;10%), a dihydroxy-flavanone, was found in the composition of an unusual brand of a subtropical Brazilian propolis. Incidentally, this sealing material was obtained from hives surrounding a large forestry site based on a single exotic flora, namely poplar (Populus sp.). Examination of the different botanical parts of poplar revealed the buds as the main source of the flavanone. Techniques used for the establishment of the chemical correlation between the propolis brand and the poplar buds were TLC/densitometry, capillary GC-MS in the e.i. mode, and CZE with DAD monitoring. Since color enhancement after Al3+ complexation applies just for more hydroxylated flavonoids, the alternative techniques herein applied were of value for pinocembrin detection and estimation. Analytical data indicated the dominance of the main phenolic pinocembrin biomarker as well as the presence of other related flavonoids in the botanical source and in the propolis derived thereof.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16905288?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Berlizov, A N</style></author><author><style face="normal" font="default" size="100%">Blum, O B</style></author><author><style face="normal" font="default" size="100%">Filby, R H</style></author><author><style face="normal" font="default" size="100%">Malyuk, I A</style></author><author><style face="normal" font="default" size="100%">Tryshyn, V V</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Testing applicability of black poplar (Populus nigra L.) bark to heavy metal air pollution monitoring in urban and industrial regions.</style></title><secondary-title><style face="normal" font="default" size="100%">The Science of the total environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Sci. Total Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jan 1</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">372</style></volume><pages><style face="normal" font="default" size="100%">693-706</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A comparative study of the capabilities of black poplar-tree (Populus nigra L.) bark as a biomonitor of atmospheric heavy-metal pollution is reported. Performance indicators (concentrations and enrichment factors) of heavy metal bioaccumulation of bark were compared to the corresponding indicators of epiphytic lichens Xanthoria parietina (L.) Th. Fr. and Physcia adscendens (Fr.) H. Oliver, collected simultaneously with bark samples within the Kiev urban-industrial conurbation. The concentrations of 40 minor and trace elements in the samples were measured by a combination of epithermal and instrumental neutron activation analysis (NAA) using a 10 MW nuclear research reactor WWR-M as the neutron source. Statistical analysis of the data was carried out using non-parametric tests. It was shown that for the majority of the elements determined a good correlation exists between their concentrations in bark and in the lichen species. The accumulation capability of the bark was found to be as effective as, and in some cases better, for both types of lichens. Based on the background levels and variations of the elemental concentration in black poplar-tree bark, threshold values for the enrichment factors were established. For a number of elements (As, Au, Ce, Co, Cr, Cu, La, Mn, Mo, Ni, Sb, Sm, Ti, Th, U, V, W) an interspecies calibration was performed. An optimized pre-irradiation treatment of the bark sample was employed which efficiently separated the most informative external layer from the deeper layers of the bark and thus minimized variations of the element concentrations. Results of this study support black poplar-tree bark as an alternative to epiphytic lichens for heavy metal air pollution monitoring in urban and industrial regions, where severe environmental conditions may result in scarcity or even lack of the indicator species.</style></abstract><issue><style face="normal" font="default" size="100%">2-3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17140640?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sćiban, Marina</style></author><author><style face="normal" font="default" size="100%">Radetić, Bogdanka</style></author><author><style face="normal" font="default" size="100%">Kevresan, Zarko</style></author><author><style face="normal" font="default" size="100%">Klasnja, Mile</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Adsorption of heavy metals from electroplating wastewater by wood sawdust.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioresource technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bioresour. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">98</style></volume><pages><style face="normal" font="default" size="100%">402-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Poplar wood sawdust was examined for adsorption as a replacement for current, more expensive methods of removing copper, zinc and cadmium from electroplating wastewater. Langmuir, Freundlich, BET and competitive Langmuir (two competing ions) isotherms were fitted to experimental data and the goodness of their fit for adsorption was compared. The shapes of isotherms obtained fitted well with multilayer adsorption. This was established and confirmed through solid correspondence between the BET equation and experimental data, in contrast to an observed monolayer adsorption of metal ions on poplar sawdust in single metal-water solutions. The adsorption of copper ions from a mixture (in wastewater) was better than that from a single metal solution. The adsorptions of zinc ions from wastewater and from model water were approximately equal, while that of cadmium ions was significantly lower from the wastewater than from model water. The aforementioned suggests that the presence of other ions in wastewater hindered adsorption of cadmium ions.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16469494?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Loivamäki, Maaria</style></author><author><style face="normal" font="default" size="100%">Louis, Sandrine</style></author><author><style face="normal" font="default" size="100%">Cinege, Gyöngyi</style></author><author><style face="normal" font="default" size="100%">Zimmer, Ina</style></author><author><style face="normal" font="default" size="100%">Fischbach, Robert J</style></author><author><style face="normal" font="default" size="100%">Schnitzler, Jörg-Peter</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Circadian rhythms of isoprene biosynthesis in grey poplar leaves.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">143</style></volume><pages><style face="normal" font="default" size="100%">540-51</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Isoprene (2-methyl-1,3-butadiene) emission varies diurnally in different species. In poplar (Populus spp.), it has recently been shown that the gene encoding the synthesizing enzyme for isoprene, isoprene synthase (ISPS), displays diurnal variation in expression. Working on shoot cultures of Grey poplar (Populus x canescens) placed under a different light regime in phytochambers, we showed that these variations in PcISPS gene expression, measured by quantitative real-time polymerase chain reaction, are not only due to day-night changes, but also are linked to an internal circadian clock. Measurement of additional selected isoprenoid genes revealed that phytoene synthase (carotenoid pathway) displays similar fluctuations, whereas 1-deoxy-d-xylulose 5-phosphate reductoisomerase, possibly the first committed enzyme of the 1-deoxy-d-xylulose 5-phosphate pathway, only shows light regulation. On the protein level, it appeared that PcISPS activity and protein content became reduced under constant darkness, whereas under constant light, activity and protein content of this enzyme were kept high. In contrast, isoprene emission rates under continuous irradiation displayed circadian changes as is the case for gene expression of PcISPS. Furthermore, binding assays with Arabidopsis (Arabidopsis thaliana) late elongated hypocotyl, a transcription factor of Arabidopsis involved in circadian regulation, clearly revealed the presence of circadian-determining regulatory elements in the promoter region of PcISPS.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17122071?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Srivastava, Vaibhav</style></author><author><style face="normal" font="default" size="100%">Schinkel, Helga</style></author><author><style face="normal" font="default" size="100%">Witzell, Johanna</style></author><author><style face="normal" font="default" size="100%">Hertzberg, Magnus</style></author><author><style face="normal" font="default" size="100%">Torp, Mikaela</style></author><author><style face="normal" font="default" size="100%">Srivastava, Manoj Kumar</style></author><author><style face="normal" font="default" size="100%">Karpinska, Barbara</style></author><author><style face="normal" font="default" size="100%">Melzer, Michael</style></author><author><style face="normal" font="default" size="100%">Wingsle, Gunnar</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Downregulation of high-isoelectric-point extracellular superoxide dismutase mediates alterations in the metabolism of reactive oxygen species and developmental disturbances in hybrid aspen.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">49</style></volume><pages><style face="normal" font="default" size="100%">135-48</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Transgenic hybrid aspen (Populus tremula L. x P. tremuloides Michx.) plants expressing a high-isoelectric-point superoxide dismutase (hipI-SOD) gene in antisense orientation were generated to investigate its function. Immunolocalization studies showed the enzyme to be localized extracellularly, in the secondary cell wall of xylem vessels and phloem fibers. The antisense lines of hipI-SOD exhibited a distinct phenotype; growth rate was reduced, stems were thinner and leaves smaller than in wild-type (WT) plants. The abundance of hipI-SOD was reduced in the bark and xylem of plants from these antisense lines. The vascular tissue of transgenic lines became lignified earlier than in WT plants and also showed an increased accumulation of reactive oxygen species (ROS). Xylem fibers and vessels were shorter and thinner in the transgenic lines than in WT plants. The total phenolic content was enhanced in the antisense lines. Furthermore, microarray analysis indicated that several enzymes involved in cell signaling, lignin biosynthesis and stress responses were upregulated in apical vascular tissues of transgenic plants. The upregulation of selected genes involved in lignin biosynthesis was also verified by real-time PCR. The results suggest that, in the transgenic plants, a premature transition into maturation occurs and the process is discussed in terms of the effects of increased accumulation of ROS due to reduced expression of hipI-SOD during development and differentiation.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17233796?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Vandecasteele, Bart</style></author><author><style face="normal" font="default" size="100%">Du Laing, Gijs</style></author><author><style face="normal" font="default" size="100%">Tack, Filip M G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Effect of submergence-emergence sequence and organic matter or aluminosilicate amendment on metal uptake by woody wetland plant species from contaminated sediments.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">145</style></volume><pages><style face="normal" font="default" size="100%">329-38</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Site-specific hydrological conditions affect the availability of trace metals for vegetation. In a greenhouse experiment, the effect of submersion on the metal uptake by the wetland plant species Salix cinerea and Populus nigra grown on a contaminated dredged sediment-derived soil and on an uncontaminated soil was evaluated. An upland hydrological regime for the polluted sediment caused elevated Cd concentrations in leaves and cuttings for both species. Emergence and soil oxidation after initial submersion of a polluted sediment resulted in comparable foliar Cd and Zn concentrations for S. cinerea as for the constant upland treatment. The foliar Cd and Zn concentrations were clearly higher than for submerged soils after initial upland conditions. These results point at the importance of submergence-emergence sequence for plant metal availability. The addition of foliar-based organic matter or aluminosilicates to the polluted sediment-derived soil in upland conditions did not decrease Cd and Zn uptake by S. cinerea.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16678320?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Yuan, Joshua S</style></author><author><style face="normal" font="default" size="100%">Yang, Xiaohan</style></author><author><style face="normal" font="default" size="100%">Lai, Jingru</style></author><author><style face="normal" font="default" size="100%">Lin, Hong</style></author><author><style face="normal" font="default" size="100%">Cheng, Zong-Ming</style></author><author><style face="normal" font="default" size="100%">Nonogaki, Hiroyuki</style></author><author><style face="normal" font="default" size="100%">Chen, Feng</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The endo-beta-mannanase gene families in Arabidopsis, rice, and poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Functional &amp; integrative genomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Funct. Integr. Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">7</style></volume><pages><style face="normal" font="default" size="100%">1-16</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Mannans are widespread hemicellulosic polysaccharides in plant cell walls. Hydrolysis of the internal beta-1,4-D: -mannopyranosyl linkage in the backbone of mannans is catalyzed by endo-beta-mannanase. Plant endo-beta-mannanase has been well studied for its function in seed germination. Its involvement in other plant biological processes, however, remains poorly characterized or elusive. The completed genome sequences of Arabidopsis (Arabidopsis thaliana), rice (Oryza sativa), and poplar (Populus trichocarpa) provide an opportunity to conduct comparative genomic analysis of endo-beta-mannanase genes in these three species. In silico sequence analysis led to the identification of eight, nine and 11 endo-beta-mannanase genes in the genomes of Arabidopsis, rice, and poplar, respectively. Sequence comparisons revealed the conserved amino acids and motifs that are critical for the active site of endo-beta-mannanases. Intron/exon structure analysis in conjunction with phylogenetic analysis implied that both intron gain and intron loss has played roles in the evolution of endo-beta-mannanase genes. The phylogenetic analysis that included the endo-beta-mannanases from plants and other organisms implied that plant endo-beta-mannanases have an ancient evolutionary origin. Comprehensive expression analysis of all Arabidopsis and rice endo-beta-mannanase genes showed divergent expression patterns of individual genes, suggesting that the enzymes encoded by these genes, while carrying out the same biochemical reaction, are involved in diverse biological processes.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16897088?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Pavy, Nathalie</style></author><author><style face="normal" font="default" size="100%">Johnson, James J</style></author><author><style face="normal" font="default" size="100%">Crow, John A</style></author><author><style face="normal" font="default" size="100%">Paule, Charles</style></author><author><style face="normal" font="default" size="100%">Kunau, Timothy</style></author><author><style face="normal" font="default" size="100%">MacKay, John</style></author><author><style face="normal" font="default" size="100%">Retzel, Ernest F</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">ForestTreeDB: a database dedicated to the mining of tree transcriptomes.</style></title><secondary-title><style face="normal" font="default" size="100%">Nucleic acids research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Nucleic Acids Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">35</style></volume><pages><style face="normal" font="default" size="100%">D888-94</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">ForestTreeDB is intended as a resource that centralizes large-scale expressed sequence tag (EST) sequencing results from several tree species (http://foresttree.org/ftdb). It currently encompasses 344,878 quality sequences from 68 libraries, from diverse organs of conifer and hybrid poplar trees. It utilizes the Nimbus data model to provide a hosting system for multiple projects, and uses object-relational mapping APIs in Java and Perl for data accesses within an Oracle database designed to be scalable, maintainable and extendable. Transcriptome builds or unigene sets occupy the focal point of the system. Several of the five current species-specific unigenes were used to design microarrays and SNP resources. The ForestTreeDB web application provides the means for multiple combination database queries. It presents the user with a list of discrete queries to retrieve and download large EST datasets or sequences from precompiled unigene assemblies. Functional annotation assignment is not trivial in conifers which are distantly related to angiosperm model plants. Optimal annotations are achieved through database queries that integrate results from several procedures based open-source tools. ForestTreeDB aims to facilitate sequence mining of coherent annotations in multiple species to support comparative genomic approaches. We plan to continuously enrich ForestTreeDB with other resources through collaborations with other genomic projects.</style></abstract><issue><style face="normal" font="default" size="100%">Database issue</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17130142?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kintisch, Eli</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Clint Chapple profile. How to make biofuels truly poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Science (New York, N.Y.)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Science</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Feb 9</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">315</style></volume><pages><style face="normal" font="default" size="100%">786</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">5813</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17289973?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rouhier, Nicolas</style></author><author><style face="normal" font="default" size="100%">Kauffmann, Brice</style></author><author><style face="normal" font="default" size="100%">Tete-Favier, Frédérique</style></author><author><style face="normal" font="default" size="100%">Palladino, Pasquale</style></author><author><style face="normal" font="default" size="100%">Gans, Pierre</style></author><author><style face="normal" font="default" size="100%">Branlant, Guy</style></author><author><style face="normal" font="default" size="100%">Jacquot, Jean-Pierre</style></author><author><style face="normal" font="default" size="100%">Boschi-Muller, Sandrine</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Functional and structural aspects of poplar cytosolic and plastidial type a methionine sulfoxide reductases.</style></title><secondary-title><style face="normal" font="default" size="100%">The Journal of biological chemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Biol. Chem.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Feb 2</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">282</style></volume><pages><style face="normal" font="default" size="100%">3367-78</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The genome of Populus trichocarpa contains five methionine sulfoxide reductase A genes. Here, both cytosolic (cMsrA) and plastidial (pMsrA) poplar MsrAs were analyzed. The two recombinant enzymes are active in the reduction of methionine sulfoxide with either dithiothreitol or poplar thioredoxin as a reductant. In both enzymes, five cysteines, at positions 46, 81, 100, 196, and 202, are conserved. Biochemical and enzymatic analyses of the cysteine-mutated MsrAs support a catalytic mechanism involving three cysteines at positions 46, 196, and 202. Cys(46) is the catalytic cysteine, and the two C-terminal cysteines, Cys(196) and Cys(202), are implicated in the thioredoxin-dependent recycling mechanism. Inspection of the pMsrA x-ray three-dimensional structure, which has been determined in this study, strongly suggests that contrary to bacterial and Bos taurus MsrAs, which also contain three essential Cys, the last C-terminal Cys(202), but not Cys(196), is the first recycling cysteine that forms a disulfide bond with the catalytic Cys(46). Then Cys(202) forms a disulfide bond with the second recycling cysteine Cys(196) that is preferentially reduced by thioredoxin. In agreement with this assumption, Cys(202) is located closer to Cys(46) compared with Cys(196) and is included in a (202)CYG(204) signature specific for most plant MsrAs. The tyrosine residue corresponds to the one described to be involved in substrate binding in bacterial and B. taurus MsrAs. In these MsrAs, the tyrosine residue belongs to a similar signature as found in plant MsrAs but with the first C-terminal cysteine instead of the last C-terminal cysteine.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17135266?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Stobrawa, Krzysztof</style></author><author><style face="normal" font="default" size="100%">Lorenc-Plucińska, Gabriela</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Changes in carbohydrate metabolism in fine roots of the native European black poplar (Populus nigra L.) in a heavy-metal-polluted environment.</style></title><secondary-title><style face="normal" font="default" size="100%">The Science of the total environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Sci. Total Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Feb 1</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">373</style></volume><pages><style face="normal" font="default" size="100%">157-65</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Effects of copper-smelter-related deposition of heavy metals in the soil on carbohydrate metabolism of fine roots of the native European black poplar were investigated in spring and autumn. Total soluble non-structural carbohydrates in fine roots from trees growing in the polluted habitat were lower than in a control site, but this was directly associated only with a lower raffinose concentration. Neither glucose nor fructose concentrations differed significantly between polluted and unpolluted sites. In contrast, the galactose concentration was higher in the presence of heavy metals, especially in autumn. Also the stachyose concentration was higher in the polluted site, but only in autumn, suggesting it could be an alternative way of detoxification of galactose. No difference between control and polluted stands was observed in sucrose concentration. However, estimates of sucrolytic activity revealed markedly higher activities of sucrose synthase (SuSy), soluble acid (AI) and neutral (NI) invertases in the polluted stand than in the control. In contrast, the estimated glycolytic enzyme activities were not affected by the presence of heavy metals in soil.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17182084?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Geagea, M Lahd</style></author><author><style face="normal" font="default" size="100%">Stille, P</style></author><author><style face="normal" font="default" size="100%">Millet, M</style></author><author><style face="normal" font="default" size="100%">Perrone, Th</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">REE characteristics and Pb, Sr and Nd isotopic compositions of steel plant emissions.</style></title><secondary-title><style face="normal" font="default" size="100%">The Science of the total environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Sci. Total Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Feb 1</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">373</style></volume><pages><style face="normal" font="default" size="100%">404-19</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A comprehensive Pb-Sr-Nd isotope and REE tracer study of atmospheric trace metal pollution by a steel plant situated to the north of the urban communities of Strasbourg (France) and Kehl (Germany) has been performed using tree barks as biomonitors. The 206Pb/207Pb and 208Pb/207Pb isotopic ratios of the steel plant's filter dust are similar to values found in dust of waste incinerators. The 87Sr/86Sr ratio is similar to present-day ratios of Phanerozoic or Precambrian granitic rocks. The 143Nd/144Nd isotopic composition is very low and corresponds to an (Nd) value of -17.5. Such a low value is characteristic of old Precambrian granitic rocks and banded iron formations. Thus, this low (Nd) value might point to the origin of the iron necessary for the steel production. The fact, that this isotopic composition does not occur in crustal rocks of Western Central Europe makes the Nd isotope ratio a powerful tool to trace steel plants atmospheric emissions. The rare earth element (REE) distribution pattern of the steel plant's filter dust shows very specific fractionations like La and Nd enrichments which are traceable in tree barks over a distance of 4 km. The Pb, Sr and Nd isotope ratios not only enable the steel plant's emissions to be traced in a north-easterly direction, along the principal wind pathway but also enables the interference of this emission at 4 km NE from the steel plant with another atmospheric component originating from the Strasbourg Rhine harbour to be identified.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17175008?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lexer, C</style></author><author><style face="normal" font="default" size="100%">Buerkle, C A</style></author><author><style face="normal" font="default" size="100%">Joseph, J A</style></author><author><style face="normal" font="default" size="100%">Heinze, B</style></author><author><style face="normal" font="default" size="100%">Fay, M F</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Admixture in European Populus hybrid zones makes feasible the mapping of loci that contribute to reproductive isolation and trait differences.</style></title><secondary-title><style face="normal" font="default" size="100%">Heredity</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Heredity (Edinb)</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">98</style></volume><pages><style face="normal" font="default" size="100%">74-84</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The use of admixed human populations to scan the genome for chromosomal segments affecting complex phenotypic traits has proved a powerful analytical tool. However, its potential in other organisms has not yet been evaluated. Here, we use DNA microsatellites to assess the feasibility of this approach in hybrid zones between two members of the 'model tree' genus Populus: Populus alba (white poplar) and Populus tremula (European aspen). We analyzed samples of both species and a Central European hybrid zone (N=544 chromosomes) for a genome-wide set of 19 polymorphic DNA microsatellites. Our results indicate that allele frequency differentials between the two species are substantial (mean delta=0.619+/-0.067). Background linkage disequilibrium (LD) in samples of the parental gene pools is moderate and should respond to sampling schemes that minimize drift and account for rare alleles. LD in hybrids decays with increasing number of backcross generations as expected from theory and approaches background levels of the parental gene pools in advanced generation backcrosses. Introgression from P. tremula into P. alba varies strongly across marker loci. For several markers, alleles from P. tremula are slightly over-represented relative to neutral expectations, whereas a single locus exhibits evidence of selection against P. tremula genotypes. We interpret our results in terms of the potential for admixture mapping in these two ecologically divergent Populus species, and we validate a modified approach of studying genotypic clines in 'mosaic' hybrid zones.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16985509?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Qin, Ruijun</style></author><author><style face="normal" font="default" size="100%">Hirano, Yasuhiro</style></author><author><style face="normal" font="default" size="100%">Brunner, Ivano</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Exudation of organic acid anions from poplar roots after exposure to Al, Cu and Zn.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">27</style></volume><pages><style face="normal" font="default" size="100%">313-20</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We studied the effects of a 2-day exposure to aluminum (Al), copper (Cu) and zinc (Zn) stress on root exudates and root apices of aseptically grown poplar (Populus tremula L.) cuttings. Aluminum induced root exudation of oxalate and citrate, Cu induced root exudation of oxalate, malate and formate, and Zn induced root exudation of formate. The threshold treatment concentrations were 100 microM for Cu and 500 microM for Al and Zn, corresponding to about 30 microM Cu2+, 140 microM Al3+ and 290 microM Zn2+. Simultaneous with the increase in organic acid anion exudation, sulfate and the nutrient cations K+, Ca2+ and Mg2+ were released into the solutions. Significant positive correlations between the organic acid anions and the cations indicate possible co-release. Toxicity symptoms of the poplar roots included browning of the root apices, which occurred at Cu concentrations of 50 microM and above, at Zn concentrations of 500 microM and above, and at an Al concentration of 1000 microM, and callose formation, which was observed solely in response to Al concentrations of 500 microM or higher. The results indicate that the composition of the exuded organic acid anions from poplar roots and the toxicity symptoms are specific to each of the applied heavy metals.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17241973?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bogeat-Triboulot, Marie-Béatrice</style></author><author><style face="normal" font="default" size="100%">Brosché, Mikael</style></author><author><style face="normal" font="default" size="100%">Renaut, Jenny</style></author><author><style face="normal" font="default" size="100%">Jouve, Laurent</style></author><author><style face="normal" font="default" size="100%">Le Thiec, Didier</style></author><author><style face="normal" font="default" size="100%">Fayyaz, Payam</style></author><author><style face="normal" font="default" size="100%">Vinocur, Basia</style></author><author><style face="normal" font="default" size="100%">Witters, Erwin</style></author><author><style face="normal" font="default" size="100%">Laukens, Kris</style></author><author><style face="normal" font="default" size="100%">Teichmann, Thomas</style></author><author><style face="normal" font="default" size="100%">Altman, Arie</style></author><author><style face="normal" font="default" size="100%">Hausman, Jean-François</style></author><author><style face="normal" font="default" size="100%">Polle, Andrea</style></author><author><style face="normal" font="default" size="100%">Kangasjärvi, Jaakko</style></author><author><style face="normal" font="default" size="100%">Dreyer, Erwin</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Gradual soil water depletion results in reversible changes of gene expression, protein profiles, ecophysiology, and growth performance in Populus euphratica, a poplar growing in arid regions.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">143</style></volume><pages><style face="normal" font="default" size="100%">876-92</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The responses of Populus euphratica Oliv. plants to soil water deficit were assessed by analyzing gene expression, protein profiles, and several plant performance criteria to understand the acclimation of plants to soil water deficit. Young, vegetatively propagated plants originating from an arid, saline field site were submitted to a gradually increasing water deficit for 4 weeks in a greenhouse and were allowed to recover for 10 d after full reirrigation. Time-dependent changes and intensity of the perturbations induced in shoot and root growth, xylem anatomy, gas exchange, and water status were recorded. The expression profiles of approximately 6,340 genes and of proteins and metabolites (pigments, soluble carbohydrates, and oxidative compounds) were also recorded in mature leaves and in roots (gene expression only) at four stress levels and after recovery. Drought successively induced shoot growth cessation, stomatal closure, moderate increases in oxidative stress-related compounds, loss of CO2 assimilation, and root growth reduction. These effects were almost fully reversible, indicating that acclimation was dominant over injury. The physiological responses were paralleled by fully reversible transcriptional changes, including only 1.5% of the genes on the array. Protein profiles displayed greater changes than transcript levels. Among the identified proteins for which expressed sequence tags were present on the array, no correlation was found between transcript and protein abundance. Acclimation to water deficit involves the regulation of different networks of genes in roots and shoots. Such diverse requirements for protecting and maintaining the function of different plant organs may render plant engineering or breeding toward improved drought tolerance more complex than previously anticipated.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17158588?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Yang, Yingli</style></author><author><style face="normal" font="default" size="100%">Zhang, Feng</style></author><author><style face="normal" font="default" size="100%">Zhao, Meigui</style></author><author><style face="normal" font="default" size="100%">An, Lizhe</style></author><author><style face="normal" font="default" size="100%">Zhang, Lixin</style></author><author><style face="normal" font="default" size="100%">Chen, Nianlai</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Properties of plasma membrane H+ -ATPase in salt-treated Populus euphratica callus.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant cell reports</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Rep.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">26</style></volume><pages><style face="normal" font="default" size="100%">229-35</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The plasma membrane (PM) vesicles from Populus euphratica (P. euphratica) callus were isolated to investigate the properties of the PM H(+)-ATPase. An enrichment of sealed and oriented right-side-out PM vesicles was demonstrated by measurement of the purity and orientation of membrane vesicles in the upper phase fraction. Analysis of pH optimum, temperature effects and kinetic properties showed that the properties of the PM H(+)-ATPase from woody plant P. euphratica callus were consistent with those from herbaceous species. Application of various thiol reagents to the reaction revealed that reduced thiol groups were essential to maintain the PM H(+)-ATPase activity. In addition, there was increased H(+)-ATPase activity in the PM vesicles when callus was exposed to NaCl. Western blotting analysis demonstrated an enhancement of H(+)-ATPase content in NaCl-treated P. euphratica callus compared with the control.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16912866?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Komárek, M</style></author><author><style face="normal" font="default" size="100%">Tlustos, P</style></author><author><style face="normal" font="default" size="100%">Száková, J</style></author><author><style face="normal" font="default" size="100%">Chrastný, V</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The role of chloride salts in chemically enhanced phytoextraction of heavy metals from a contaminated agricultural soil.</style></title><secondary-title><style face="normal" font="default" size="100%">Bulletin of environmental contamination and toxicology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bull Environ Contam Toxicol</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">78</style></volume><pages><style face="normal" font="default" size="100%">176-80</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17401509?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Piens, Kathleen</style></author><author><style face="normal" font="default" size="100%">Henriksson, Anna-Maria</style></author><author><style face="normal" font="default" size="100%">Gullfot, Fredrika</style></author><author><style face="normal" font="default" size="100%">Lopez, Marie</style></author><author><style face="normal" font="default" size="100%">Fauré, Régis</style></author><author><style face="normal" font="default" size="100%">Ibatullin, Farid M</style></author><author><style face="normal" font="default" size="100%">Teeri, Tuula T</style></author><author><style face="normal" font="default" size="100%">Driguez, Hugues</style></author><author><style face="normal" font="default" size="100%">Brumer, Harry</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Glycosynthase activity of hybrid aspen xyloglucan endo-transglycosylase PttXET16-34 nucleophile mutants.</style></title><secondary-title><style face="normal" font="default" size="100%">Organic &amp; biomolecular chemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Org. Biomol. Chem.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Dec 21</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">5</style></volume><pages><style face="normal" font="default" size="100%">3971-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Glycosynthases are active-site mutants of glycoside hydrolases that catalyse glycosyl transfer using suitable activated donor substrates without competing product hydrolysis (S. M. Hancock, M. D. Vaughan and S. G. Withers, Curr. Opin. Chem. Biol., 2006, 10, 509-519). Site-directed mutagenesis of the catalytic nucleophile, Glu-85, of a Populus tremula x tremuloides xyloglucan endo-transglycosylase (PttXET16-34, EC 2.4.1.207) into alanine, glycine, and serine yielded enzymes with glycosynthase activity. Product analysis indicated that PttXET16-34 E85A in particular was able to catalyse regio- and stereospecific homo- and hetero-condensations of alpha-xylogluco-oligosaccharyl fluoride donors XXXGalphaF and XLLGalphaF to produce xyloglucans with regular sidechain substitution patterns. This substrate promiscuity contrasts that of the Humicola insolens Cel7B E197A glycosynthase, which was not able to polymerise the di-galactosylated substrate XLLGalphaF. The production of the PttXET16-34 E85A xyloglucosynthase thus expands the repertoire of glycosynthases to include those capable of synthesising structurally homogenenous xyloglucans for applications.</style></abstract><issue><style face="normal" font="default" size="100%">24</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18043802?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hernández Torres, Jorge</style></author><author><style face="normal" font="default" size="100%">Maldonado, Mónica Alexandra Arias</style></author><author><style face="normal" font="default" size="100%">Chomilier, Jacques</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Tandem duplications of a degenerated GTP-binding domain at the origin of GTPase receptors Toc159 and thylakoidal SRP.</style></title><secondary-title><style face="normal" font="default" size="100%">Biochemical and biophysical research communications</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biochem. Biophys. Res. Commun.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Dec 14</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">364</style></volume><pages><style face="normal" font="default" size="100%">325-31</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The evolutionary origin of some nuclear encoded proteins that translocate proteins across the chloroplast envelope remains unknown. Therefore, sequences of GTPase proteins constituting the Arabidopsis thaliana translocon at the outer membrane of chloroplast (atToc) complexes were analyzed by means of HCA. In particular, atToc159 and related proteins (atToc132, atToc120, and atToc90) do not have proven homologues of prokaryotic or eukaryotic ancestry. We established that the three domains commonly referred to as A, G, and M originate from the GTPase G domain, tandemly repeated, and probably evolving toward an unstructured conformation in the case of the A domain. It resulted from this study a putative common ancestor for these proteins and a new domain definition, in particular the splitting of A into three domains (A1, A2, and A3), has been proposed. The family of Toc159, previously containing A. thaliana and Pisum sativum, has been extended to Medicago truncatula and Populus trichocarpa and it has been revised for Oryza sativa. They have also been compared to GTPase subunits involved in the cpSRP system. A distant homology has been revealed among Toc and cpSRP GTP-hydrolyzing proteins of A. thaliana, and repetitions of a GTPase domain were also found in cpSRP protein receptors, by means of HCA analysis.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17950698?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Pitre, Frederic E</style></author><author><style face="normal" font="default" size="100%">Pollet, Brigitte</style></author><author><style face="normal" font="default" size="100%">Lafarguette, Florian</style></author><author><style face="normal" font="default" size="100%">Cooke, Janice E K</style></author><author><style face="normal" font="default" size="100%">MacKay, John J</style></author><author><style face="normal" font="default" size="100%">Lapierre, Catherine</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Effects of increased nitrogen supply on the lignification of poplar wood.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of agricultural and food chemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Agric. Food Chem.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Dec 12</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">55</style></volume><pages><style face="normal" font="default" size="100%">10306-14</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The short-term influence of adequate and high nitrogen fertilization on poplar lignification was investigated. The high nitrogen supply decreased lignin staining in the newly formed secondary xylem, indicating that lignin deposition was affected. Acetyl bromide determinations gave a 9-10% decrease in lignin content; however, Klason lignin content was unchanged. Thioacidolysis showed that elevated N supply affected lignin structure such that there was a reduced frequency of lignin units involved in beta-O-4 bonds, a reduced syringyl/guaiacyl ratio, an increased frequency of p-hydroxyphenyl lignin units, more guaiacyl units with free phenolic groups, and more p-hydroxybenzoic acid ester-linked to poplar lignins. These features suggest that lignins from poplars grown under high N bear structural similarities to lignins formed during early stages of wood development. The findings also indicate that a gravitational stimulus inducing the formation of tension wood and high N availability lead to similar and additive effects on lignin content and structure.</style></abstract><issue><style face="normal" font="default" size="100%">25</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17988087?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hall, David</style></author><author><style face="normal" font="default" size="100%">Luquez, Virginia</style></author><author><style face="normal" font="default" size="100%">Garcia, M Victoria</style></author><author><style face="normal" font="default" size="100%">St Onge, Kate R</style></author><author><style face="normal" font="default" size="100%">Jansson, Stefan</style></author><author><style face="normal" font="default" size="100%">Ingvarsson, Pär K</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Adaptive population differentiation in phenology across a latitudinal gradient in European aspen (Populus tremula, L.): a comparison of neutral markers, candidate genes and phenotypic traits.</style></title><secondary-title><style face="normal" font="default" size="100%">Evolution; international journal of organic evolution</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Evolution</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">61</style></volume><pages><style face="normal" font="default" size="100%">2849-60</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A correct timing of growth cessation and dormancy induction represents a critical ecological and evolutionary trade-off between survival and growth in most forest trees (Rehfeldt et al. 1999; Horvath et al. 2003; Howe et al. 2003). We have studied the deciduous tree European Aspen (Populus tremula) across a latitudinal gradient and compared genetic differentiation in phenology traits with molecular markers. Trees from 12 different areas covering 10 latitudinal degrees were cloned and planted in two common gardens. Several phenology traits showed strong genetic differentiation and clinal variation across the latitudinal gradient, with Q(ST) values generally exceeding 0.5. This is in stark contrast to genetic differentiation at several classes of genetic markers (18 neutral SSRs, 7 SSRs located close to phenology candidate genes and 50 SNPs from five phenology candidate genes) that all showed F(ST) values around 0.015. We thus find strong evidence for adaptive divergence in phenology traits across the latitudinal gradient. However, the strong population structure seen at the quantitative traits is not reflected in underlying candidate genes. This result fit theoretical expectations that suggest that genetic differentiation at candidate loci is better described by F(ST) at neutral loci rather than by Q(ST) at the quantitative traits themselves.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17908247?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bylesjö, Max</style></author><author><style face="normal" font="default" size="100%">Eriksson, Daniel</style></author><author><style face="normal" font="default" size="100%">Kusano, Miyako</style></author><author><style face="normal" font="default" size="100%">Moritz, Thomas</style></author><author><style face="normal" font="default" size="100%">Trygg, Johan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Data integration in plant biology: the O2PLS method for combined modeling of transcript and metabolite data.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">52</style></volume><pages><style face="normal" font="default" size="100%">1181-91</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The technological advances in the instrumentation employed in life sciences have enabled the collection of a virtually unlimited quantity of data from multiple sources. By gathering data from several analytical platforms, with the aim of parallel monitoring of, e.g. transcriptomic, metabolomic or proteomic events, one hopes to answer and understand biological questions and observations. This 'systems biology' approach typically involves advanced statistics to facilitate the interpretation of the data. In the present study, we demonstrate that the O2PLS multivariate regression method can be used for combining 'omics' types of data. With this methodology, systematic variation that overlaps across analytical platforms can be separated from platform-specific systematic variation. A study of Populus tremula x Populus tremuloides, investigating short-day-induced effects at transcript and metabolite levels, is employed to demonstrate the benefits of the methodology. We show how the models can be validated and interpreted to identify biologically relevant events, and discuss the results in relation to a pairwise univariate correlation approach and principal component analysis.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17931352?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Straw, N A</style></author><author><style face="normal" font="default" size="100%">Green, G</style></author><author><style face="normal" font="default" size="100%">Williams, D T</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Dieback and recovery in poplar and attack by the hornet clearwing moth, Sesia apiformis (Clerck) (Lepidoptera: Sesiidae).</style></title><secondary-title><style face="normal" font="default" size="100%">Bulletin of entomological research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bull. Entomol. Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">97</style></volume><pages><style face="normal" font="default" size="100%">555-67</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A survey of 801 poplar trees in central east England in 1999 demonstrated a correlation between crown dieback and infestation by hornet clearwing moth (Sesia apiformis), induced by a period of drought in 1995-1996. To determine whether trees colonised by S. apiformis would subsequently deteriorate and die or whether they could recover despite infestation and damage to the stem, all trees in the original survey were re-assessed in 2001, 2003 and 2005. The repeat surveys showed that trees with 70% or less crown dieback in 1999 replaced their canopy and generally improved by 2005, irrespective of the numbers of S. apiformis in the stem, whereas trees that had 75% or more crown dieback in 1999 either died or declined further. The presence of S. apiformis did not prevent tree recovery, and there was little evidence that infestation slowed the rate of recovery. Populations of S. apiformis, measured in terms of the numbers of adult emergence holes visible in the base of the trees, decreased between 2001 and 2005 at the same time as the amount of dieback visible in the canopy of the poplars markedly decreased. However, the fall in numbers of emergence holes at this time reflected a decline in larval establishment 2-3 years earlier, and indicated that the moth population had responded to a more rapid restoration in the internal state of the trees, which was not reflected immediately by the gradual replacement of dead branches and reduction in dieback symptoms.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17997868?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Manzanera, Jose A</style></author><author><style face="normal" font="default" size="100%">Martínez-Chacón, Maria F</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Ecophysiological competence of Populus alba L., Fraxinus angustifolia Vahl., and Crataegus monogyna Jacq. used in plantations for the recovery of riparian vegetation.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental management</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ Manage</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">40</style></volume><pages><style face="normal" font="default" size="100%">902-12</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In many semi-arid environments of Mediterranean ecosystems, white poplar (Populus alba L.) is the dominant riparian tree and has been used to recover degraded areas, together with other native species, such as ash (Fraxinus angustifolia Vahl.) and hawthorn (Crataegus monogyna Jacq.). We addressed three main objectives: (1) to gain an improved understanding of some specific relationships between environmental parameters and leaf-level physiological factors in these riparian forest species, (2) to compare the leaf-level physiology of these riparian species to each other, and (3) to compare leaf-level responses within native riparian plots to adjacent restoration plots, in order to evaluate the competence of the plants used for the recovery of those degraded areas. We found significant differences in physiological performance between mature and young white poplars in the natural stand and among planted species. The net assimilation and transpiration rates, diameter, and height of white poplar plants were superior to those of ash and hawthorn. Ash and hawthorn showed higher water use efficiency than white poplar. White poplar also showed higher levels of stomatal conductance, behaving as a fast-growing, water-consuming species with a more active gas exchange and ecophysiological competence than the other species used for restoration purposes. In the restoration zones, the planted white poplars had higher rates of net assimilation and water use efficiency than the mature trees in the natural stand. We propose the use of white poplar for the rapid restoration of riparian vegetation in semi-arid Mediterranean environments. Ash and hawthorn can also play a role as accompanying species for the purpose of biodiversity.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17849159?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhuang, Yan</style></author><author><style face="normal" font="default" size="100%">Adams, Keith L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Extensive allelic variation in gene expression in populus F1 hybrids.</style></title><secondary-title><style face="normal" font="default" size="100%">Genetics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Genetics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">177</style></volume><pages><style face="normal" font="default" size="100%">1987-96</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Hybridization between plant species can induce speciation as well as phenotypic novelty and heterosis. Hybrids also can show genome rearrangements and gene expression changes compared with their parents. Here we determined the allelic variation in gene expression in Populus trichocarpa x Populus deltoides F(1) hybrids. Among 30 genes analyzed in four independently formed hybrids, 17 showed &gt;1.5-fold expression biases for one of the two alleles, and there was monoallelic expression of one gene. Expression ratios of the alleles differed between leaves and stems for 10 genes. The results suggest differential regulation of the two parental alleles in the hybrids. To determine if the allelic expression biases were caused by hybridization we compared the ratios of species-specific transcripts between an F(1) hybrid and its parents. Thirteen of 19 genes showed allelic expression ratios in the hybrid that were significantly different from the ratios of the parental species. The P. deltoides allele of one gene was silenced in the hybrid. Modes of gene regulation were inferred from the hybrid-parent comparisons. Cis-regulation was inferred for 6 genes, trans-regulation for 1 gene, and combined cis- and trans-regulation for 9 genes. The results from this study indicate that hybridization between plant species can have extensive effects on allelic expression patterns, some of which might lead to phenotypic changes.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18073418?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wooley, Stuart C</style></author><author><style face="normal" font="default" size="100%">Donaldson, Jack R</style></author><author><style face="normal" font="default" size="100%">Stevens, Michael T</style></author><author><style face="normal" font="default" size="100%">Gusse, Adam C</style></author><author><style face="normal" font="default" size="100%">Lindroth, Richard L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Extrafloral nectaries in aspen (Populus tremuloides): heritable genetic variation and herbivore-induced expression.</style></title><secondary-title><style face="normal" font="default" size="100%">Annals of botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ann. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">100</style></volume><pages><style face="normal" font="default" size="100%">1337-46</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A wide variety of plants produce extrafloral nectaries (EFNs) that are visited by predatory arthropods. But very few studies have investigated the relationship between plant genetic variation and EFNs. The presence of foliar EFNs is highly variable among different aspen (Populus tremuloides) genotypes and the EFNs are visited by parasitic wasps and predatory flies. The aim here was to determine the heritability of EFNs among aspen genotypes and age classes, possible trade-offs between direct and indirect defences, EFN induction following herbivory, and the relationship between EFNs and predatory insects.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17951361?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Menges, Margit</style></author><author><style face="normal" font="default" size="100%">Pavesi, Giulio</style></author><author><style face="normal" font="default" size="100%">Morandini, Piero</style></author><author><style face="normal" font="default" size="100%">Bögre, Laszlo</style></author><author><style face="normal" font="default" size="100%">Murray, James A H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genomic organization and evolutionary conservation of plant D-type cyclins.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">145</style></volume><pages><style face="normal" font="default" size="100%">1558-76</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Plants contain more genes encoding core cell cycle regulators than other organisms but it is unclear whether these represent distinct functions. D-type cyclins (CYCD) play key roles in the G1-to-S-phase transition, and Arabidopsis (Arabidopsis thaliana) contains 10 CYCD genes in seven defined subgroups, six of which are conserved in rice (Oryza sativa). Here, we identify 22 CYCD genes in the poplar (Populus trichocarpa) genome and confirm that these six CYCD subgroups are conserved across higher plants, suggesting subgroup-specific functions. Different subgroups show gene number increases, with CYCD3 having three members in Arabidopsis, six in poplar, and a single representative in rice. All three species contain a single CYCD7 gene. Despite low overall sequence homology, we find remarkable conservation of intron/exon boundaries, because in most CYCD genes of plants and mammals, the first exon ends in the conserved cyclin signature. Only CYCD3 genes contain the complete cyclin box in a single exon, and this structure is conserved across angiosperms, again suggesting an early origin for the subgroup. The single CYCD gene of moss has a gene structure closely related to those of higher plants, sharing an identical exon/intron structure with several higher plant subgroups. However, green algae have CYCD genes structurally unrelated to higher plants. Conservation is also observed in the location of potential cyclin-dependent kinase phosphorylation sites within CYCD proteins. Subgroup structure is supported by conserved regulatory elements, particularly in the eudicot species, including conserved E2F regulatory sites within CYCD3 promoters. Global expression correlation analysis further supports distinct expression patterns for CYCD subgroups.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17951462?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lee, Hyoshin</style></author><author><style face="normal" font="default" size="100%">Bae, Eun-Kyung</style></author><author><style face="normal" font="default" size="100%">Park, So-Young</style></author><author><style face="normal" font="default" size="100%">Sjödin, Andreas</style></author><author><style face="normal" font="default" size="100%">Lee, Jae-Soon</style></author><author><style face="normal" font="default" size="100%">Noh, Eun-Woon</style></author><author><style face="normal" font="default" size="100%">Jansson, Stefan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Growth-phase-dependent gene expression profiling of poplar (Populus alba x Populus tremula var. glandulosa) suspension cells.</style></title><secondary-title><style face="normal" font="default" size="100%">Physiologia plantarum</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Physiol Plant</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">131</style></volume><pages><style face="normal" font="default" size="100%">599-613</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Complex sequences of morphological and biochemical changes occur during the developmental course of a batch plant cell culture. However, little information is available about the changes in gene expression that could explain these changes, because of the difficulties involved in isolating specific cellular events or developmental phases in the overlapping phases of cell growth. In an attempt to obtain such information we have examined the global growth phase-dependent gene expression of poplar cells in suspension cultures by cDNA microarray analysis. Our results reveal that significant changes occur in the expression of genes with functions related to protein synthesis, cell cycling, hormonal responses and cell wall biosynthesis, as cultures progress from initiation to senescence, that are highly correlated with observed developmental and physiological changes in the cells. Genes encoding protein kinases, calmodulin and proteins involved in both ascorbate metabolism and water-limited stress responses also showed strong stage-specific expression patterns. Our report provides fundamental information on molecular mechanisms that control cellular changes throughout the developmental course of poplar cell cultures.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18251851?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Funk, Jennifer L</style></author><author><style face="normal" font="default" size="100%">Jones, Clive G</style></author><author><style face="normal" font="default" size="100%">Lerdau, Manuel T</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Leaf- and shoot-level plasticity in response to different nutrient and water availabilities.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">27</style></volume><pages><style face="normal" font="default" size="100%">1731-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Phenotypic plasticity in response to environmental variation occurs at all levels of organization and across temporal scales within plants. However, the magnitude and functional significance of plasticity is largely unexplored in perennial species. We measured the plasticity of leaf- and shoot-level physiological, morphological and developmental traits in nursery-grown Populus deltoides Bartr. ex Marsh. individuals subjected to different nutrient and water availabilities. We also examined the extent to which nutrient and water availability influenced the relationships between these traits and productivity. Populus deltoides responded to changes in resource availability with high plasticity in shoot-level traits and moderate plasticity in leaf-level traits. Although shoot-level traits generally correlated strongly with productivity across fertilization and irrigation treatments, few leaf-level traits correlated with productivity, and the relationships depended on the resource examined. In fertilized plants, leaf nitrogen concentration was negatively correlated with productivity, suggesting that growth, rather than enhanced leaf quality, is an important response to fertilization in this species. With the exception of photosynthetic nitrogen-use efficiency, traits associated with resource conservation (leaf senescence rate, water-use efficiency and leaf mass per area) were uncorrelated with short-term productivity in nutrient- and water-stressed plants. Our results suggest that plasticity in shoot-level growth traits has a greater impact on plant productivity than does plasticity in leaf-level traits and that the relationships between traits and productivity are highly resource dependent.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17938104?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Palmroth, Marja R T</style></author><author><style face="normal" font="default" size="100%">Koskinen, Perttu E P</style></author><author><style face="normal" font="default" size="100%">Kaksonen, Anna H</style></author><author><style face="normal" font="default" size="100%">Münster, Uwe</style></author><author><style face="normal" font="default" size="100%">Pichtel, John</style></author><author><style face="normal" font="default" size="100%">Puhakka, Jaakko A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Metabolic and phylogenetic analysis of microbial communities during phytoremediation of soil contaminated with weathered hydrocarbons and heavy metals.</style></title><secondary-title><style face="normal" font="default" size="100%">Biodegradation</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biodegradation</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">18</style></volume><pages><style face="normal" font="default" size="100%">769-82</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In the current study, the microbial ecology of weathered hydrocarbon and heavy metal contaminated soil undergoing phytoremediation was studied. The relationship of functional diversity, measured as carbon source utilisation in Biolog plates and extracellular enzymatic activities, and genetic diversity of bacteria was evaluated. Denaturing gradient gel electrophoresis was used for community analyses at the species level. Bulk soil and rhizosphere soil from pine and poplar plantations were analysed separately to determine if the plant rhizosphere impacted hydrocarbon degradation. Prevailing microbial communities in the field site were both genetically and metabolically diverse. Furthermore, both tree rhizosphere and fertilisation affected the compositions of these communities and increased activities of extracellular aminopeptidases. In addition, the abundance of alkane hydroxylase and naphthalene dioxygenase genes in the communities was low, but the prevalence of these genes was increased by the addition of bioavailable hydrocarbons. Tree rhizosphere communities had greater hydrocarbon degradation potential than those of bulk soil. Hydrocarbon utilising communities were dominated generally by the species Ralstonia eutropha and bacteria belonging to the genus Burkholderia. Despite the presence of viable hydrocarbon-degrading microbiota, decomposition of hydrocarbons from weathered hydrocarbon contaminated soil over four years, regardless of the presence of vegetation, was low in unfertilised soil. Compost addition enhanced the removal of hydrocarbons.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17372705?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wimp, G M</style></author><author><style face="normal" font="default" size="100%">Wooley, S</style></author><author><style face="normal" font="default" size="100%">Bangert, R K</style></author><author><style face="normal" font="default" size="100%">Young, W P</style></author><author><style face="normal" font="default" size="100%">Martinsen, G D</style></author><author><style face="normal" font="default" size="100%">Keim, P</style></author><author><style face="normal" font="default" size="100%">Rehill, B</style></author><author><style face="normal" font="default" size="100%">Lindroth, R L</style></author><author><style face="normal" font="default" size="100%">Whitham, T G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Plant genetics predicts intra-annual variation in phytochemistry and arthropod community structure.</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Ecol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">16</style></volume><pages><style face="normal" font="default" size="100%">5057-69</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">With the emerging field of community genetics, it is important to quantify the key mechanisms that link genetics and community structure. We studied cottonwoods in common gardens and in natural stands and examined the potential for plant chemistry to be a primary mechanism linking plant genetics and arthropod communities. If plant chemistry drives the relationship between plant genetics and arthropod community structure, then several predictions followed. We would find (i) the strongest correlation between plant genetic composition and chemical composition; (ii) an intermediate correlation between plant chemical composition and arthropod community composition; and (iii) the weakest relationship between plant genetic composition and arthropod community composition. Our results supported our first prediction: plant genetics and chemistry had the strongest correlation in the common garden and the wild. Our results largely supported our second prediction, but varied across space, seasonally, and according to arthropod feeding group. Plant chemistry played a larger role in structuring common garden arthropod communities relative to wild communities, free-living arthropods relative to leaf and stem modifiers, and early-season relative to late-season arthropods. Our results did not support our last prediction, as host plant genetics was at least as tightly linked to arthropod community structure as plant chemistry, if not more so. Our results demonstrate the consistency of the relationship between plant genetics and biodiversity. Additionally, plant chemistry can be an important mechanism by which plant genetics affects arthropod community composition, but other genetic-based factors are likely involved that remain to be measured.</style></abstract><issue><style face="normal" font="default" size="100%">23</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17927708?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Cochard, Hervé</style></author><author><style face="normal" font="default" size="100%">Casella, Eric</style></author><author><style face="normal" font="default" size="100%">Mencuccini, Maurizio</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Xylem vulnerability to cavitation varies among poplar and willow clones and correlates with yield.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">27</style></volume><pages><style face="normal" font="default" size="100%">1761-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Xylem vulnerability to cavitation is a promising criterion for identifying trees with high drought tolerance, but traditional techniques for measuring cavitation resistance are unsuitable for screening large numbers of genotypes. We tested the potential of the new Cavitron technique for high throughput screening of cavitation resistance in five poplar (Populus spp.) and four willow (Salix spp.) clones. The Cavitron technique enabled the screening of three to four clones per day with sufficient accuracy to reveal significant differences between clones. Because intraspecific screening may be better carried out through the identification of correlated and more easily measured traits, we attempted to identify accessible parameters that correlate to cavitation resistance. Variability in vulnerability to cavitation across clones was poorly correlated with anatomical traits such as vessel diameter, vessel wall strength, wood density and fiber wall thickness; however, a striking correlation was established between cavitation resistance and aboveground biomass production, indicating a possible trade-off between xylem safety and growth potential.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17938107?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Calfapietra, Carlo</style></author><author><style face="normal" font="default" size="100%">Angelis, Paolo de</style></author><author><style face="normal" font="default" size="100%">Gielen, Birgit</style></author><author><style face="normal" font="default" size="100%">Lukac, Martin</style></author><author><style face="normal" font="default" size="100%">Moscatelli, Maria Cristina</style></author><author><style face="normal" font="default" size="100%">Avino, Giuseppina</style></author><author><style face="normal" font="default" size="100%">Lagomarsino, Alessandra</style></author><author><style face="normal" font="default" size="100%">Polle, Andrea</style></author><author><style face="normal" font="default" size="100%">Ceulemans, Reinhart</style></author><author><style face="normal" font="default" size="100%">Mugnozza, Giuseppe Scarascia</style></author><author><style face="normal" font="default" size="100%">Hoosbeek, Marcel R</style></author><author><style face="normal" font="default" size="100%">Cotrufo, Maria Francesca</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Increased nitrogen-use efficiency of a short-rotation poplar plantation in elevated CO(2) concentration.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">27</style></volume><pages><style face="normal" font="default" size="100%">1153-63</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We estimated nitrogen (N) use by trees of three poplar species exposed for 3 years to free air CO(2) enrichment (FACE) and determined whether the CO(2) treatment affected the future N availability of the plantation. Trees were harvested at the end of the first 3-year rotation and N concentration and content of woody tissues determined. Nitrogen uptake of fine roots and litter was measured throughout the first crop rotation. The results were related to previously published variations in soil N content during the same period. We estimated retranslocation from green leaves and processes determining N mobilization and immobilization, such as mineralization and nitrification, and N immobilization in litter and microbial biomass. In all species, elevated CO(2) concentration ([CO(2)]) significantly increased nitrogen-use efficiency (NUE; net primary productivity per unit of annual N uptake), decreased N concentration in most plant tissues, but did not significantly change cumulative N uptake by trees over the rotation. Total soil N was depleted more in elevated [CO(2)] than in ambient [CO(2)], although not significantly for all soil layers. The effect of elevated [CO(2)] was usually similar for all species, although differences among species were sometimes significant. During the first 3-year rotation, productivity of the plantation remained high in the elevated [CO(2)] treatment. However, we observed a potential reduction in N availability in response to elevated [CO(2)].</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17472941?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Vigneault, Frédéric</style></author><author><style face="normal" font="default" size="100%">Lachance, Denis</style></author><author><style face="normal" font="default" size="100%">Cloutier, Monikca</style></author><author><style face="normal" font="default" size="100%">Pelletier, Gervais</style></author><author><style face="normal" font="default" size="100%">Levasseur, Caroline</style></author><author><style face="normal" font="default" size="100%">Séguin, Armand</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Members of the plant NIMA-related kinases are involved in organ development and vascularization in poplar, Arabidopsis and rice.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">51</style></volume><pages><style face="normal" font="default" size="100%">575-88</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">NIMA-related kinases (Neks) are a family of serine/threonine kinases that have been linked to cell-cycle regulation in fungi and mammals. Information regarding the function of Neks in plants is very limited. We screened the three plant species that have had their genomes sequenced in an attempt to improve our understanding of their role in plants. We retrieved seven members in Arabidopsis thaliana, nine in Populus trichocarpa and six in Oryza sativa. Phylogenetic analysis showed that plant Neks are closely related to each other and contain paralogous genes. Moreover, their chromosome distribution and their exon-intron structure revealed that the actual plant Nek family was derived from a single representative followed by large segmental duplication events. Functional expression analyses in the three species relied on RTqPCR in poplar and publicly available microarray data for Arabidopsis and rice. Although plant Neks are present in every organ analyzed, their expression profiles suggest their involvement in plant development processes. Furthermore, we showed that PNek1, a member of the poplar family, is expressed at sites of free auxin synthesis and is specifically involved during the vascularization process.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17886359?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ruttink, Tom</style></author><author><style face="normal" font="default" size="100%">Arend, Matthias</style></author><author><style face="normal" font="default" size="100%">Morreel, Kris</style></author><author><style face="normal" font="default" size="100%">Storme, Véronique</style></author><author><style face="normal" font="default" size="100%">Rombauts, Stephane</style></author><author><style face="normal" font="default" size="100%">Fromm, Jörg</style></author><author><style face="normal" font="default" size="100%">Bhalerao, Rishikesh P</style></author><author><style face="normal" font="default" size="100%">Boerjan, Wout</style></author><author><style face="normal" font="default" size="100%">Rohde, Antje</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A molecular timetable for apical bud formation and dormancy induction in poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant cell</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">19</style></volume><pages><style face="normal" font="default" size="100%">2370-90</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The growth of perennial plants in the temperate zone alternates with periods of dormancy that are typically initiated during bud development in autumn. In a systems biology approach to unravel the underlying molecular program of apical bud development in poplar (Populus tremula x Populus alba), combined transcript and metabolite profiling were applied to a high-resolution time course from short-day induction to complete dormancy. Metabolite and gene expression dynamics were used to reconstruct the temporal sequence of events during bud development. Importantly, bud development could be dissected into bud formation, acclimation to dehydration and cold, and dormancy. To each of these processes, specific sets of regulatory and marker genes and metabolites are associated and provide a reference frame for future functional studies. Light, ethylene, and abscisic acid signal transduction pathways consecutively control bud development by setting, modifying, or terminating these processes. Ethylene signal transduction is positioned temporally between light and abscisic acid signals and is putatively activated by transiently low hexose pools. The timing and place of cell proliferation arrest (related to dormancy) and of the accumulation of storage compounds (related to acclimation processes) were established within the bud by electron microscopy. Finally, the identification of a large set of genes commonly expressed during the growth-to-dormancy transitions in poplar apical buds, cambium, or Arabidopsis thaliana seeds suggests parallels in the underlying molecular mechanisms in different plant organs.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17693531?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhou, Meng</style></author><author><style face="normal" font="default" size="100%">Tong, Chun-Fa</style></author><author><style face="normal" font="default" size="100%">Shi, Ji-Sen</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A preliminary analysis of synonymous codon usage in poplar species.</style></title><secondary-title><style face="normal" font="default" size="100%">Zhi wu sheng li yu fen zi sheng wu xue xue bao = Journal of plant physiology and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Zhi Wu Sheng Li Yu Fen Zi Sheng Wu Xue Xue Bao</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">33</style></volume><pages><style face="normal" font="default" size="100%">285-93</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Poplar is among the most important deciduous tree species in plantations over the world and has been used as an important model system for molecular genetics of trees. The analysis of codon usage may improve the understanding of the mechanism of codon distribution and variation in poplar and the understanding of factors shaping the codon usage patterns. Here, an EN(c) (effective number of codons)-plot method and multivariate statistical method called correspondence analysis (COA) were used to examine the codon usage of 314 genes of poplar. The results show that the main trend was highly negative correlated with the gene expression level assessed by the ''Codon Adaptation Index'' value. Moreover, there were two significant correlations between axis 1 coordinates and GC3(s) content and gene length, we infer that gene nucleotide composition and gene length also play an important role in shaping the codon usage bias in poplar. The result of relative synonymous codon usage (RSCU) analysis shows a high bias of codon usage toward the codon with A or T ending. In addition, we compared the codon preferences among poplar, Arabidopsis thaliana, Oryza sative, Homo sapiens and Escherichia coli, and poplar was found to be most similar to A.thaliana and least similar to E.coli. In this paper, 10 codons defined firstly as optimal codons through an analysis of the high-expression codon in poplar may provide some useful information for genetic engineering of poplar.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17675751?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Oka, Michiko</style></author><author><style face="normal" font="default" size="100%">Tachibana, Masaki</style></author><author><style face="normal" font="default" size="100%">Noda, Kumiko</style></author><author><style face="normal" font="default" size="100%">Inoue, Naoki</style></author><author><style face="normal" font="default" size="100%">Tanaka, Mitsushi</style></author><author><style face="normal" font="default" size="100%">Kuwabara, Kenji</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Relevance of anti-reactive oxygen species activity to anti-inflammatory activity of components of eviprostat, a phytotherapeutic agent for benign prostatic hyperplasia.</style></title><secondary-title><style face="normal" font="default" size="100%">Phytomedicine : international journal of phytotherapy and phytopharmacology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Phytomedicine</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">14</style></volume><pages><style face="normal" font="default" size="100%">465-72</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Inflammation is a common finding in benign prostatic hyperplasia (BPH). The phytotherapeutic agent eviprostat is a popular treatment for BPH in Japan and Germany. This agent consists of five components; four are extracted from Chimaphila umbellata, Populus tremula, Pulsatilla pratensis and Equisetum arvense (coded as EVI-1, EVI-2, EVI-3 and EVI-4, respectively) and the fifth is germ oil from Triticum aestivum (coded as EVI-5). In this study, the effects of each component on the reactive oxygen species (ROS), superoxide anion (O2-) and hydroxyl radical (OH*) generated in cell-free systems and human neutrophils, and on carrageenin-induced paw edema in rats were investigated. EVI-1, EVI-2 and EVI-4 suppressed the O2- levels in the xanthine/xanthine oxidase system, and EVI-1, EVI-2, EVI-3 and EVI-4 abolished the OH* produced in a Fenton-type reaction system, so that EVI-1, EVI-2 and EVI-4 possessed inhibitory action with respect to both O2- and OH*. EVI-1, EVI-2 and EVI-4 also reduced ROS levels in phorbol myristate acetate-stimulated neutrophils. The paw swelling was inhibited by a mixture of EVI-1, EVI-2, EVI-3, EVI-4 and EVI-5 (a mixture which is equivalent to eviprostat) or by a mixture of EVI-1, EVI-2 and EVI-4, even though each component alone did not significantly inhibit the swelling. These findings suggest that the suppression of ROS by EVI-1, EVI-2 and EVI-4 may partly contribute to the anti-inflammatory action of eviprostat, and this action may be implicated in its therapeutic effect on BPH.</style></abstract><issue><style face="normal" font="default" size="100%">7-8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17583488?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Morse, Alison M</style></author><author><style face="normal" font="default" size="100%">Tschaplinski, Timothy J</style></author><author><style face="normal" font="default" size="100%">Dervinis, Christopher</style></author><author><style face="normal" font="default" size="100%">Pijut, Paula M</style></author><author><style face="normal" font="default" size="100%">Schmelz, Eric A</style></author><author><style face="normal" font="default" size="100%">Day, Wendy</style></author><author><style face="normal" font="default" size="100%">Davis, John M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Salicylate and catechol levels are maintained in nahG transgenic poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Phytochemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Phytochemistry</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">68</style></volume><pages><style face="normal" font="default" size="100%">2043-52</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Metabolic profiling was used to investigate the molecular phenotypes of a transgenic Populus tremula x P. alba hybrid expressing the nahG transgene, a bacterial gene encoding salicylate hydroxylase that converts salicylic acid to catechol. Despite the efficacy of this transgenic approach to reduce salicylic acid levels in other model systems and thereby elucidate roles for salicylic acid in plant signaling, transgenic poplars had similar foliar levels of salicylic acid and catechol to that of non-transformed controls and exhibited no morphological phenotypes. To gain a deeper understanding of the basis for these observations, we analyzed metabolic profiles of leaves as influenced by transgene expression. Expression of nahG decreased quinic acid conjugates and increased catechol glucoside, while exerting little effect on levels of salicylic acid and catechol, the substrate and product, respectively, of the nahG enzyme. This suggests a biological role of elevated constitutive salicylic acid levels in Populus, in contrast to other plant systems in which nahG dramatically reduces salicylic acid levels.</style></abstract><issue><style face="normal" font="default" size="100%">15</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17599371?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Behnke, Katja</style></author><author><style face="normal" font="default" size="100%">Ehlting, Barbara</style></author><author><style face="normal" font="default" size="100%">Teuber, Markus</style></author><author><style face="normal" font="default" size="100%">Bauerfeind, Martina</style></author><author><style face="normal" font="default" size="100%">Louis, Sandrine</style></author><author><style face="normal" font="default" size="100%">Hänsch, Robert</style></author><author><style face="normal" font="default" size="100%">Polle, Andrea</style></author><author><style face="normal" font="default" size="100%">Bohlmann, Jörg</style></author><author><style face="normal" font="default" size="100%">Schnitzler, Jörg-Peter</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Transgenic, non-isoprene emitting poplars don't like it hot.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">51</style></volume><pages><style face="normal" font="default" size="100%">485-99</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The physiological role of isoprene emission in plants is a matter of much debate. One of the most widely propagated hypotheses suggests a function of isoprene in the protection of leaf physiological processes against thermal and oxidative stress. To test this hypothesis, we developed transgenic Grey poplar (Populusxcanescens) plants in which gene expression of isoprene synthase (ISPS) was either silenced by RNA interference (RNAi) or upregulated by over-expression of the ISPS gene. Despite increased ISPS mRNA levels, we did not observe consistent increases in isoprene emission in the over-expressing lines, indicating post-transcriptional control of ISPS by co-suppression. In the RNAi lines, levels of isoprene emission were effectively suppressed to virtually zero. Transgenic plants were subjected to temperature stress with three transient heat phases of 38-40 degrees C, each followed by phases of recovery at 30 degrees C. Parallel measurements of gas exchange, chlorophyll fluorescence and isoprene emission provided new insights into the physiological link between isoprene and enhanced temperature tolerance. Transgenic non-isoprene-emitting poplars showed reduced rates of net assimilation and photosynthetic electron transport during heat stress, but not in the absence of stress. The decrease in the efficiency of photochemistry was inversely correlated with the increase in heat dissipation of absorbed light energy, measured as NPQ (non-photochemical quenching). Isoprene-repressed poplars also displayed an increased formation of the xanthophyll cycle pigment zeaxanthin in the absence of stress, which can cause increased NPQ or may indicate an increased requirement for antioxidants. In conclusion, using a molecular genetic approach, we show that down-regulation of isoprene emission affects thermotolerance of photosynthesis and induces increased energy dissipation by NPQ pathways.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17587235?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Li, Hai-Me</style></author><author><style face="normal" font="default" size="100%">He, Xing-Yuan</style></author><author><style face="normal" font="default" size="100%">Wang, Kui-Ling</style></author><author><style face="normal" font="default" size="100%">Chen, Wei</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Photosynthetic characteristics of five arbor species in Shenyang urban area].</style></title><secondary-title><style face="normal" font="default" size="100%">Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ying Yong Sheng Tai Xue Bao</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">18</style></volume><pages><style face="normal" font="default" size="100%">1709-14</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">By using LI-6400 infrared gas analyzer, this paper studied the diurnal and seasonal variations of the photosynthetic rate of main arbor species (Populus alba x P. berolinensis, Salix matsudana, Ulmus pumila, Robinia pseudoacacia and Prunus davidiana) in Shenyang urban area. The correlations between net photosynthetic rate and environmental factors (photosynthetic active radiation, temperature, and stomatal conductance) were assessed by multivariate regression analysis, and related equations were constructed. The results showed that for test arbor species, the diurnal variation of photosynthetic rate mainly presented a single peak curve, and the seasonal variation was in the order of summer &gt; autumn &gt; spring. The major factors affecting the photosynthetic rate were photosynthetic active radiation, stomatal conductance, and intercellular CO2 concentration.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17974233?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Cseke, Leland J</style></author><author><style face="normal" font="default" size="100%">Ravinder, Namritha</style></author><author><style face="normal" font="default" size="100%">Pandey, Ajay K</style></author><author><style face="normal" font="default" size="100%">Podila, Gopi K</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Identification of PTM5 protein interaction partners, a MADS-box gene involved in aspen tree vegetative development.</style></title><secondary-title><style face="normal" font="default" size="100%">Gene</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Gene</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Apr 15</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">391</style></volume><pages><style face="normal" font="default" size="100%">209-22</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In a past article, our lab described the identification and characterization of a novel vegetative MADS-box gene from quaking aspen trees, Populus tremuloides MADS-box 5 (PTM5). PTM5 was shown to be a member of the SOC1/TM3 class of MADS-box genes with a seasonal expression pattern specific to developing vascular tissues including the vascular cambium, the precursor to all woody branches, stems, and roots. Since the proper function of MADS-box proteins is dependent on specific interactions with other regulatory proteins, we further examined PTM5 protein-protein interactions as a means to better understand its function. Through yeast two-hybrid analyses, it was demonstrated that, like other SOC1/TM3 class proteins, PTM5 is capable of interacting with itself as well as other MADS-box proteins from aspen. In addition, yeast two-hybrid library screening revealed that PTM5 interacts with two non-MADS proteins, an actin depolymerizing factor (PtADF) and a novel leucine-rich repeat protein (PtLRR). In situ RNA localization was used to verify the overlapping expression patterns of these genes, and transgenic studies showed that over-expression of PTM5 in aspen causes alterations in root vasculature and root biomass development consistent with the cell growth and expansion functions of related ADF and LRR genes. These results suggest that the interaction of vegetative MADS-box genes with specific protein cofactors is a key step in the mechanisms that control woody tissue development in trees.</style></abstract><issue><style face="normal" font="default" size="100%">1-2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17331677?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Pan, Xuejun</style></author><author><style face="normal" font="default" size="100%">Xie, Dan</style></author><author><style face="normal" font="default" size="100%">Kang, Kyu-Young</style></author><author><style face="normal" font="default" size="100%">Yoon, Seung-Lak</style></author><author><style face="normal" font="default" size="100%">Saddler, Jack N</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Effect of organosolv ethanol pretreatment variables on physical characteristics of hybrid poplar substrates.</style></title><secondary-title><style face="normal" font="default" size="100%">Applied biochemistry and biotechnology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Appl. Biochem. Biotechnol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">137-140</style></volume><pages><style face="normal" font="default" size="100%">367-77</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Hybrid poplar (Populus nigra x P. maximowiczii) chips were pretreated using an organosolv ethanol process. The effect of pretreatment conditions (temperature, time, catalyst, and ethanol concentration) on the substrate characteristics, including fiber size, crystallinity, and degree of polymerization of cellulose, was investigated using an experimental matrix designed with response surface methodology. The conditions ranged 155-205 degrees C, 26-94 min, 0.83-1.67% catalyst (H(2)SO(4)) on oven-dry wood chip (w/w), and 25-75% ethanol concentration (v/v). The results indicated that the substrate characteristics are controllable and predictable. Desirable substrates can be prepared by fine-tuning the processing parameters. The regression models developed, allowed the quantitative prediction of the substrate characteristics from the pretreatment conditions used.</style></abstract><issue><style face="normal" font="default" size="100%">1-12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18478402?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Castiglione, Stefano</style></author><author><style face="normal" font="default" size="100%">Franchin, Cinzia</style></author><author><style face="normal" font="default" size="100%">Fossati, Tiziana</style></author><author><style face="normal" font="default" size="100%">Lingua, Guido</style></author><author><style face="normal" font="default" size="100%">Torrigiani, Patrizia</style></author><author><style face="normal" font="default" size="100%">Biondi, Stefania</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">High zinc concentrations reduce rooting capacity and alter metallothionein gene expression in white poplar (Populus alba L. cv. Villafranca).</style></title><secondary-title><style face="normal" font="default" size="100%">Chemosphere</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Chemosphere</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">67</style></volume><pages><style face="normal" font="default" size="100%">1117-26</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Poplar is a good candidate for phytoremediation purposes because of its rapid growth, extensive root system, and ease of propagation and transformation; however its tolerance to heavy metals has not been fully investigated yet. In the present work, an in vitro model system with shoot cultures was used to investigate the tolerance to high concentrations of zinc (Zn) of a commercial clone (Villafranca) of Populus alba. Based on chlorophyll content (leaf chlorosis) and the rate of adventitious root formation from shoot cuttings as parameters of damage, 0.5-4mM zinc concentrations were all toxic albeit to different extents. Northern blot and reverse transcriptase (RT)-PCR analyses were used to examine the expression profiles of types 1, 2 and 3 PaMT genes in stems, leaves and roots of plants exposed to Zn treatments. In leaves, MT1 and MT3 mRNA levels were enhanced by Zn, while MT2 transcripts were not affected. The PaMT expression profiles were differentially affected by Zn in an organ-specific manner, and the relationship with Zn concentration and exposure time was rarely linear. The developmental and molecular data reveal that the in vitro model is a sensitive and reliable system to study heavy metal stress responses.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17223164?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Adler, Paul R</style></author><author><style face="normal" font="default" size="100%">Del Grosso, Stephen J</style></author><author><style face="normal" font="default" size="100%">Parton, William J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Life-cycle assessment of net greenhouse-gas flux for bioenergy cropping systems.</style></title><secondary-title><style face="normal" font="default" size="100%">Ecological applications : a publication of the Ecological Society of America</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ecol Appl</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">17</style></volume><pages><style face="normal" font="default" size="100%">675-91</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Bioenergy cropping systems could help offset greenhouse gas emissions, but quantifying that offset is complex. Bioenergy crops offset carbon dioxide emissions by converting atmospheric CO2 to organic C in crop biomass and soil, but they also emit nitrous oxide and vary in their effects on soil oxidation of methane. Growing the crops requires energy (e.g., to operate farm machinery, produce inputs such as fertilizer) and so does converting the harvested product to usable fuels (feedstock conversion efficiency). The objective of this study was to quantify all these factors to determine the net effect of several bioenergy cropping systems on greenhouse-gas (GHG) emissions. We used the DAYCENT biogeochemistry model to assess soil GHG fluxes and biomass yields for corn, soybean, alfalfa, hybrid poplar, reed canarygrass, and switchgrass as bioenergy crops in Pennsylvania, USA. DAYCENT results were combined with estimates of fossil fuels used to provide farm inputs and operate agricultural machinery and fossil-fuel offsets from biomass yields to calculate net GHG fluxes for each cropping system considered. Displaced fossil fuel was the largest GHG sink, followed by soil carbon sequestration. N20 emissions were the largest GHG source. All cropping systems considered provided net GHG sinks, even when soil C was assumed to reach a new steady state and C sequestration in soil was not counted. Hybrid poplar and switchgrass provided the largest net GHG sinks, &gt;200 g CO2e-C x m(-2) x yr(-1) for biomass conversion to ethanol, and &gt;400 g CO2e-C x m(-2) x yr(-1) for biomass gasification for electricity generation. Compared with the life cycle of gasoline and diesel, ethanol and biodiesel from corn rotations reduced GHG emissions by approximately 40%, reed canarygrass by approximately 85%, and switchgrass and hybrid poplar by approximately 115%.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17494388?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">García-Fraile, Paula</style></author><author><style face="normal" font="default" size="100%">Rivas, Raúl</style></author><author><style face="normal" font="default" size="100%">Willems, Anne</style></author><author><style face="normal" font="default" size="100%">Peix, Alvaro</style></author><author><style face="normal" font="default" size="100%">Martens, Miet</style></author><author><style face="normal" font="default" size="100%">Martínez-Molina, Eustoquio</style></author><author><style face="normal" font="default" size="100%">Mateos, Pedro F</style></author><author><style face="normal" font="default" size="100%">Velázquez, Encarna</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Rhizobium cellulosilyticum sp. nov., isolated from sawdust of Populus alba.</style></title><secondary-title><style face="normal" font="default" size="100%">International journal of systematic and evolutionary microbiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Int. J. Syst. Evol. Microbiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">57</style></volume><pages><style face="normal" font="default" size="100%">844-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">During a study of polysaccharide-hydrolysing bacteria present in different plant sources, two strains were isolated from pulverized decaying wood of Populus alba and classified in the genus Rhizobium on basis of their almost complete 16S rRNA gene sequences. Their closest phylogenetic relatives were Rhizobium galegae USDA 4128(T) and Rhizobium huautlense S02(T), with 98.2 and 98.1 % 16S rRNA gene sequence similarity, respectively. recA and atpD sequence analysis showed that these species have less than 88 and 92 % similarity, respectively, to the novel strains. In contrast to their closest phylogenetic relatives, the two strains showed strong cellulase activity on plates containing CM-cellulose as a carbon source. They were also distinguishable from these species on the basis of other phenotypic characteristics. The strains were able to induce ineffective nodules on Medicago sativa and the sequence of their nodD gene was phylogenetically close to that of Ensifer meliloti 1021 (99.6 % similarity). DNA-DNA hybridization values ranged from 10 to 22 % with respect to R. galegae USDA 4128(T) and 14 to 25 % with respect to R. huautlense S02(T), showing that the strains from this study belong to a novel species, for which the name Rhizobium cellulosilyticum sp. nov. is proposed. The type strain is ALA10B2(T) (=LMG 23642(T)=DSM 18291(T)=CECT 7176(T)).</style></abstract><issue><style face="normal" font="default" size="100%">Pt 4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17392217?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lang, Christina</style></author><author><style face="normal" font="default" size="100%">Popko, Jennifer</style></author><author><style face="normal" font="default" size="100%">Wirtz, Markus</style></author><author><style face="normal" font="default" size="100%">Hell, Rüdiger</style></author><author><style face="normal" font="default" size="100%">Herschbach, Cornelia</style></author><author><style face="normal" font="default" size="100%">Kreuzwieser, Jürgen</style></author><author><style face="normal" font="default" size="100%">Rennenberg, Heinz</style></author><author><style face="normal" font="default" size="100%">Mendel, Ralf R</style></author><author><style face="normal" font="default" size="100%">Hänsch, Robert</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Sulphite oxidase as key enzyme for protecting plants against sulphur dioxide.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">30</style></volume><pages><style face="normal" font="default" size="100%">447-55</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Sulphur dioxide (SO(2)) is known as a strongly damaging air pollutant. After conversion to sulphite in aqueous solution, it becomes a strong nucleophilic agent that attacks numerous compounds in the cell. Therefore, plants have developed a mechanism to control sulphite levels. Recently, we have cloned and characterized the enzyme sulphite oxidase (SO) from Arabidopsis thaliana. Yet, its physiological role remained unclear. Here, we describe results demonstrating that SO is essential for detoxifying excessive amounts of sulphite in the cell which is important for the survival of the plant. T-DNA-tagged A. thaliana plants lacking the enzyme showed a decrease in vitality during SO(2) fumigation and a change in their S-metabolites. The same was found with RNA-interference (RNAi) plants that were generated for tobacco. On the contrary, over-expression of SO helped the plant to survive SO(2) concentrations that are detrimental for non-transformed wild-type (WT) plants, as was shown with poplar plants which are known to be particularly sensitive to SO(2). Fumigation induced the expression of the enzyme as demonstrated by promoter-reporter gene fusion, by immunoblot analysis of SO-protein and by induction of enzyme activity. This implies that SO, as an otherwise constitutively expressed protein, is under additional control by SO(2) in the environment.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17324231?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lv, Ping-Ping</style></author><author><style face="normal" font="default" size="100%">Hu, Jun</style></author><author><style face="normal" font="default" size="100%">Chen, Shao-Liang</style></author><author><style face="normal" font="default" size="100%">Shen, Xin</style></author><author><style face="normal" font="default" size="100%">Yin, Wei-Bo</style></author><author><style face="normal" font="default" size="100%">Chen, Yu-Hong</style></author><author><style face="normal" font="default" size="100%">Sun, Yong-Ru</style></author><author><style face="normal" font="default" size="100%">Hu, Zan-Min</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Function of the putative Na+/H+ antiporter gene PeNhaD1 from salt-resistant Populus euphratica Oliv].</style></title><secondary-title><style face="normal" font="default" size="100%">Zhi wu sheng li yu fen zi sheng wu xue xue bao = Journal of plant physiology and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Zhi Wu Sheng Li Yu Fen Zi Sheng Wu Xue Xue Bao</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">33</style></volume><pages><style face="normal" font="default" size="100%">173-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Yeast complementation experiments were carried out to define the possible function of PeNhaD1, a Na(+)/H(+) antiporter gene from Populus euphratica Oliv., a salt resistant tree. PeNhaD1 was introduced to the Saccharomyces cerevisiae mutant strain ANT3 (Deltaena1-4::HIS3 Deltanha1::LEU2), which lacks the plasma membrane Na(+)/H(+) antiporter gene ScNHA1 or GX1 (Deltanhx1::TRP1), which lacks tonoplast Na(+)/H(+) antiporter gene ScNHX1. Our results showed that PeNhaD1 rescued the normal growth of ANT3 in the presence of high salt (80 mmol/L NaCl on solid medium or 400 mmol/L in liquid medium, pH 6.0), but not that of GX1, suggesting that PeNhaD1 may play a role in salt tolerance of Populus euphratica by maintaining the capacity for salt exclusion under saline condition.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17452804?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rae, Anne M</style></author><author><style face="normal" font="default" size="100%">Tricker, Penny J</style></author><author><style face="normal" font="default" size="100%">Bunn, Stephen M</style></author><author><style face="normal" font="default" size="100%">Taylor, Gail</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Adaptation of tree growth to elevated CO2: quantitative trait loci for biomass in Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">175</style></volume><pages><style face="normal" font="default" size="100%">59-69</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">* Information on the genetic variation of plant response to elevated CO(2) (e[CO(2)]) is needed to understand plant adaptation and to pinpoint likely evolutionary response to future high atmospheric CO(2) concentrations. * Here, quantitative trait loci (QTL) for above- and below-ground tree growth were determined in a pedigree - an F(2) hybrid of poplar (Populus trichocarpa and Populus deltoides), following season-long exposure to either current day ambient CO(2) (a[CO(2)]) or e[CO(2)] at 600 microl l(-1), and genotype by environment interactions investigated. * In the F(2) generation, both above- and below-ground growth showed a significant increase in e[CO(2)]. Three areas of the genome on linkage groups I, IX and XII were identified as important in determining above-ground growth response to e[CO(2)], while an additional three areas of the genome on linkage groups IV, XVI and XIX appeared important in determining root growth response to e[CO(2)]. * These results quantify and identify genetic variation in response to e[CO(2)] and provide an insight into genomic response to the changing environment.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17547667?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Martin, M T</style></author><author><style face="normal" font="default" size="100%">Pedranzani, H E</style></author><author><style face="normal" font="default" size="100%">Sierra de Grado, R</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Behavior and preservation of an in vitro collection of European aspen in Spain.</style></title><secondary-title><style face="normal" font="default" size="100%">Biocell : official journal of the Sociedades Latinoamericanas de Microscopía Electronica ... et. al</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biocell</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">31</style></volume><pages><style face="normal" font="default" size="100%">41-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">An in vitro collection has been established with selected European aspen from Palencia province (Spain). Currently, this collection includes 32 high quality clones, selected for their good bearing and healthy state. Most of them belong to different discrete local populations. Populus tremula L. was propagated in proliferation Aspen Culture Medium; they required subculture every 3 months. The purpose of this study was, therefore, to select a medium which allows the maintenance of 32 clones for a period longer than 3 months without subculture and to observe the behavior of those clones in 15 different culture medium compositions. Seven nodal cutting stem explants from each clone were cultured in parallel in the different media. One and three months after setting on the stem explants, the number and the size of shoots, the root size, the presence or absence of callus and the survival, were evaluated. The survival was monthly recorded during 8 months. Taking into account the explant development, four media were proposed for collection preservation. One of them, Ga, with a reduction of salts, sucrose, 6-benzoaminopurine, omitting adenine sulphate and 1-naphthalene acetic acid, is the most economical. Behavior observations of the 32 clones in the 15 medium compositions showed the influence of the genotype of the clones.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17665638?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lautner, Silke</style></author><author><style face="normal" font="default" size="100%">Ehlting, Barbara</style></author><author><style face="normal" font="default" size="100%">Windeisen, Elisabeth</style></author><author><style face="normal" font="default" size="100%">Rennenberg, Heinz</style></author><author><style face="normal" font="default" size="100%">Matyssek, Rainer</style></author><author><style face="normal" font="default" size="100%">Fromm, Jörg</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Calcium nutrition has a significant influence on wood formation in poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">173</style></volume><pages><style face="normal" font="default" size="100%">743-52</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">To test the effects of calcium on wood formation, Populus tremula x Populus tremuloides clones were supplied with Hoagland solution modified in its calcium contents. Energy-dispersive X-ray analysis (EDXA) revealed an increase in calcium in the phloem, the cambium and the xylem elongation zone with increasing Ca(2+) supply in the nutrient solution. Using light and electron microscopy, a strong impact was shown on the cambial and the elongation zones under calcium starvation. Using Fourier transform infrared (FTIR) spectroscopy on wood and bark cells formed under calcium starvation, we detected a reduction of some absorptions, such as carbonyl and methoxy groups from S-lignin. Also, a significant reduction in fiber length was detected with decreasing calcium supply in the nutrient solution. High-performance liquid chromatography (HPLC) analysis revealed a large increase in sugar concentrations in the leaves, but reduced concentrations in the bark under Ca(2+) deficiency. In conclusion, our results show a significant influence of calcium on the structure, chemistry and physiology of wood formation. Thus, efficient Ca(2+) supply has to be considered a decisive factor in wood formation.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17286823?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Barakat, Abdelali</style></author><author><style face="normal" font="default" size="100%">Wall, Phillip K</style></author><author><style face="normal" font="default" size="100%">Diloreto, Scott</style></author><author><style face="normal" font="default" size="100%">Depamphilis, Claude W</style></author><author><style face="normal" font="default" size="100%">Carlson, John E</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Conservation and divergence of microRNAs in Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC genomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">8</style></volume><pages><style face="normal" font="default" size="100%">481</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">MicroRNAs (miRNAs) are small RNAs (sRNA) approximately 21 nucleotides in length that negatively control gene expression by cleaving or inhibiting the translation of target gene transcripts. miRNAs have been extensively analyzed in Arabidopsis and rice and partially investigated in other non-model plant species. To date, 109 and 62 miRNA families have been identified in Arabidopsis and rice respectively. However, only 33 miRNAs have been identified from the genome of the model tree species (Populus trichocarpa), of which 11 are Populus specific. The low number of miRNA families previously identified in Populus, compared with the number of families identified in Arabidopsis and rice, suggests that many miRNAs still remain to be discovered in Populus. In this study, we analyzed expressed small RNAs from leaves and vegetative buds of Populus using high throughput pyrosequencing.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18166134?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Mockler, T C</style></author><author><style face="normal" font="default" size="100%">Michael, T P</style></author><author><style face="normal" font="default" size="100%">Priest, H D</style></author><author><style face="normal" font="default" size="100%">Shen, R</style></author><author><style face="normal" font="default" size="100%">Sullivan, C M</style></author><author><style face="normal" font="default" size="100%">Givan, S A</style></author><author><style face="normal" font="default" size="100%">McEntee, C</style></author><author><style face="normal" font="default" size="100%">Kay, S A</style></author><author><style face="normal" font="default" size="100%">Chory, J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The DIURNAL project: DIURNAL and circadian expression profiling, model-based pattern matching, and promoter analysis.</style></title><secondary-title><style face="normal" font="default" size="100%">Cold Spring Harbor symposia on quantitative biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Cold Spring Harb. Symp. Quant. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">72</style></volume><pages><style face="normal" font="default" size="100%">353-63</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The DIURNAL project ( http://diurnal.cgrb.oregonstate.edu/ ) provides a graphical interface for mining and viewing diurnal and circadian microarray data for Arabidopsis thaliana, poplar, and rice. The database is searchable and provides access to several user-friendly Web-based data-mining tools with easy-to-understand output. The associated tools include HAYSTACK ( http://haystack.cgrb.oregonstate.edu/ ) and ELEMENT ( http://element.cgrb.oregonstate.edu/ ). HAYSTACK is a model-based pattern-matching algorithm for identifying genes that are coexpressed and potentially coregulated. HAYSTACK can be used to analyze virtually any large-scale microarray data set and provides an alternative method for clustering microarray data from any experimental system by grouping together genes whose expression patterns match the same or similar user-defined patterns. ELEMENT is a Web-based program for identifying potential cis-regulatory elements in the promoters of coregulated genes in Arabidopsis, poplar, and rice. Together, DIURNAL, HAYSTACK, and ELEMENT can be used to facilitate cross-species comparisons among the plant species supported and to accelerate functional genomics efforts in the laboratory.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18419293?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Giovannelli, Alessio</style></author><author><style face="normal" font="default" size="100%">Deslauriers, Annie</style></author><author><style face="normal" font="default" size="100%">Fragnelli, Giuseppe</style></author><author><style face="normal" font="default" size="100%">Scaletti, Luciano</style></author><author><style face="normal" font="default" size="100%">Castro, Gaetano</style></author><author><style face="normal" font="default" size="100%">Rossi, Sergio</style></author><author><style face="normal" font="default" size="100%">Crivellaro, Alan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Evaluation of drought response of two poplar clones (Populus x canadensis Monch 'I-214' and P. deltoides Marsh. 'Dvina') through high resolution analysis of stem growth.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of experimental botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Exp. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">58</style></volume><pages><style face="normal" font="default" size="100%">2673-83</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Different irrigation effects on stem radius variation (DeltaR) and maximum daily shrinkage (MDS) in Populus deltoides 'Dvina' and Populusxcanadensis 'I-214' were studied to assess differences in drought tolerance between clones. One-year-old trees growing in concrete tanks were submitted to two irrigation regimes (natural rainfall and irrigation) from 24 June to 10 August, and DeltaR was monitored by automatic point dendrometers. Independently of the irrigation regime, 'Dvina' showed a higher stem radial increment than 'I-214'. In both clones, the first response to changed soil water content was a significant increase in MDS, whilst DeltaR decreased about 20 d later when pre-dawn leaf water potential (Psipd) dropped below -0.4 MPa. However, they displayed different strategies to overcome drought. 'Dvina' maintained a positive DeltaR for longer than 'I-214', which had lower leaf Psipd and greater leaf abscission at the end of the drought period. After irrigation resumed, 'Dvina' showed a higher capacity to restore stem growth. 'I-214' was probably unable to recover secondary growth because of higher leaf abscission during drought stress and the production of newly expanded leaves during recovery. It is concluded that the larger radial growth of 'Dvina' derived from a better water use (carbon uptake versus water loss) than 'I-214' under limited water availability.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17545226?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Couturier, Jérémy</style></author><author><style face="normal" font="default" size="100%">Montanini, Barbara</style></author><author><style face="normal" font="default" size="100%">Martin, Francis</style></author><author><style face="normal" font="default" size="100%">Brun, Annick</style></author><author><style face="normal" font="default" size="100%">Blaudez, Damien</style></author><author><style face="normal" font="default" size="100%">Chalot, Michel</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The expanded family of ammonium transporters in the perennial poplar plant.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">174</style></volume><pages><style face="normal" font="default" size="100%">137-50</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">* Ammonium and nitrate are the prevalent nitrogen sources for growth and development of higher plants. Here, we report on the characterization of the ammonium transporter (AMT) family in the perennial species Populus trichocarpa. * In silico analysis and expression analysis of AMT genes from poplar was performed. In addition, AMT1;2 and AMT1;6 function was studied in detail by heterologous expression in yeast. * The P. trichocarpa genome contains 14 putative AMTs, which is more than twice the number of AMTs in Arabidopsis. In roots, the high-affinity AMT1;2 strongly increased upon mycorrhiza formation and might be partly responsible for the high-affinity ammonium uptake component measured in poplar. Transcript level for the high-affinity AMT1;6 was strongly affected by the diurnal cycle. AMT3;1 was exclusively expressed in senescing poplar leaves. Remarkably AMT2;1 was highly expressed in leaves while AMT2;2 was mostly expressed in petioles. Specific expression of AMT1;5 in stamen and of AMT1;6 in female flower indicate that they have key functions in reproductive organ development in poplar. * The present study provides basic genomic and transcriptomic information for the poplar AMT family and will pave the way for deciphering the precise role of AMTs in poplar physiology.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17335504?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Nanjo, Tokihiko</style></author><author><style face="normal" font="default" size="100%">Sakurai, Tetsuya</style></author><author><style face="normal" font="default" size="100%">Totoki, Yasushi</style></author><author><style face="normal" font="default" size="100%">Toyoda, Atsushi</style></author><author><style face="normal" font="default" size="100%">Nishiguchi, Mitsuru</style></author><author><style face="normal" font="default" size="100%">Kado, Tomoyuki</style></author><author><style face="normal" font="default" size="100%">Igasaki, Tomohiro</style></author><author><style face="normal" font="default" size="100%">Futamura, Norihiro</style></author><author><style face="normal" font="default" size="100%">Seki, Motoaki</style></author><author><style face="normal" font="default" size="100%">Sakaki, Yoshiyuki</style></author><author><style face="normal" font="default" size="100%">Shinozaki, Kazuo</style></author><author><style face="normal" font="default" size="100%">Shinohara, Kenji</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Functional annotation of 19,841 Populus nigra full-length enriched cDNA clones.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC genomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">8</style></volume><pages><style face="normal" font="default" size="100%">448</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Populus is one of favorable model plants because of its small genome. Structural genomics of Populus has reached a breakpoint as nucleotides of the entire genome have been determined. Reaching the post genome era, functional genomics of Populus is getting more important for well-comprehended plant science. Development of bioresorce serving functional genomics is making rapid progress. Huge efforts have achieved deposits of expressed sequence tags (ESTs) in various plant species consequently accelerating functional analysis of genes. ESTs from full-length cDNA clones are especially powerful for accurate molecular annotation. We promoted collection and annotation of the ESTs from Populus full-length enriched cDNA clones as part of functional genomics of tree species.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18053163?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rohde, Antje</style></author><author><style face="normal" font="default" size="100%">Ruttink, Tom</style></author><author><style face="normal" font="default" size="100%">Hostyn, Vanessa</style></author><author><style face="normal" font="default" size="100%">Sterck, Lieven</style></author><author><style face="normal" font="default" size="100%">Van Driessche, Klara</style></author><author><style face="normal" font="default" size="100%">Boerjan, Wout</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Gene expression during the induction, maintenance, and release of dormancy in apical buds of poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of experimental botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Exp. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">58</style></volume><pages><style face="normal" font="default" size="100%">4047-60</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The perennial lifestyle of trees is characterized by seasonal cycles of growth and dormancy. The recurrent transitions into and out of dormancy represent an adaptation mechanism that largely determines survival and, hence, the geographical distribution of tree species. To understand better the molecular basis of bud dormancy, cDNA-amplified fragment length polymorphism (AFLP) transcript profiling was used to map differential gene expression during dormancy induction, dormancy, dormancy release by chilling, and subsequent bud break in apical buds of poplar (Populus tremulaxP. alba). Unexpectedly, besides poplar transcript sequences, the cDNA-AFLP profiles revealed sequence signatures originating from a complex bacterial community, which was more pronounced during dormancy and displayed temporal dynamics in composition and complexity. Based on poplar gene expression dynamics, processes and potential regulators during different phases of dormancy are described. Novel genes were linked to a crucial transitory step in dormancy induction, and to dormancy release through chilling, a molecularly unresolved phenomenon. One WRKY- and two ERF-related transcription factors were similarly expressed during the transition to dormancy in apical and axillary buds. These regulatory genes could be involved in the differentiation of stipule-like leaf organs protecting the bud, or act during the growth-dormancy transition in the meristem, revealing commonalities between para- and endodormancy.</style></abstract><issue><style face="normal" font="default" size="100%">15-16</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18039739?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kalluri, Udaya C</style></author><author><style face="normal" font="default" size="100%">Difazio, Stephen P</style></author><author><style face="normal" font="default" size="100%">Brunner, Amy M</style></author><author><style face="normal" font="default" size="100%">Tuskan, Gerald A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genome-wide analysis of Aux/IAA and ARF gene families in Populus trichocarpa.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC plant biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Plant Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">7</style></volume><pages><style face="normal" font="default" size="100%">59</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Auxin/Indole-3-Acetic Acid (Aux/IAA) and Auxin Response Factor (ARF) transcription factors are key regulators of auxin responses in plants. We identified the suites of genes in the two gene families in Populus and performed comparative genomic analysis with Arabidopsis and rice.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17986329?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Attia Al Hagrey, Said</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Geophysical imaging of root-zone, trunk, and moisture heterogeneity.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of experimental botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Exp. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">58</style></volume><pages><style face="normal" font="default" size="100%">839-54</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The most significant biotic and abiotic stress agents of water extremity, salinity, and infection lead to wood decay and modifications of moisture and ion content, and density. This strongly influences the (di-)electrical and mechanical properties and justifies the application of geophysical imaging techniques. These are less invasive and have high resolution in contrast to classical methods of destructive, single-point measurements for inspecting stresses in trees and soils. This review presents some in situ and in vivo applications of electric, radar, and seismic methods for studying water status and movement in soils, roots, and tree trunks. The electrical properties of a root-zone are a consequence of their moisture content. Electrical imaging discriminates resistive, woody roots from conductive, soft roots. Both types are recognized by low radar velocities and high attenuation. Single roots can generate diffraction hyperbolas in radargrams. Pedophysical relationships of water content to electrical resistivity and radar velocity are established by diverse infiltration experiments in the field, laboratory, and in the full-scale 'GeoModel' at Kiel University. Subsurface moisture distributions are derived from geophysical attribute models. The ring electrode technique around trunks images the growth ring structure of concentric resistivity, which is inversely proportional to the fluid content. Healthy trees show a central high resistivity within the dry heartwood that strongly decreases towards the peripheral wet sapwood. Observed structural deviations are caused by infection, decay, shooting, or predominant light and/or wind directions. Seismic trunk tomography also differentiates between decayed and healthy woods.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17229759?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rajinikanth, Mohan</style></author><author><style face="normal" font="default" size="100%">Harding, Scott A</style></author><author><style face="normal" font="default" size="100%">Tsai, Chung-Jui</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The glycine decarboxylase complex multienzyme family in Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of experimental botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Exp. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">58</style></volume><pages><style face="normal" font="default" size="100%">1761-70</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In plants, the glycine decarboxylase complex (GDC) cooperates with serine hydroxymethyltransferase (SHMT) to mediate photorespiratory glycine-serine interconversion. GDC is also postulated to be an integral component of one-carbon (C1) metabolism in heterotrophic tissues, although molecular evidence in plants is scarce. An initial report of a xylem-specific isoform of GDC component H-protein, PtgdcH1, in aspen (Populus tremuloides Michx.) provided molecular evidence consistent with an important role for GDC in plant C1 metabolism. PtgdcH1 is phylogenetically distinct from the leaf-abundant photorespiratory PtgdcH3, but both isoforms restored GDC activity in a yeast H-protein knockout mutant, suggesting their functional equivalence. The Populus genome contains eight transcriptionally active GDC genes, encoding four H-proteins, two T-proteins, and single P- and L-proteins. The two Populus T-protein isoforms, PtgdcT1 and PtgdcT2, exhibited differential expression in leaves and xylem, similar to PtgdcH3 and PtgdcH1. In silico identification of AC elements in the promoters of xylem-abundant PtgdcH1 and PtgdcT2, as well as many lignin biosynthetic genes of Populus is consistent with a prominent role for GDC in methyl-intensive lignification during wood formation. The AC element is absent from Arabidopsis GDC promoters, and GDC expression has not been linked to secondary growth in this herbaceous annual. Taken together, the results suggest that the association of distinct H-protein and T-protein isoforms with photorespiration and C1 metabolism is a distinguishing feature of Populus, and may signify molecular adaptation of GDC to cope with the C1 demands of lignification in woody perennials.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17355947?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Myllys, Leena</style></author><author><style face="normal" font="default" size="100%">Stenroos, Soili</style></author><author><style face="normal" font="default" size="100%">Thell, Arne</style></author><author><style face="normal" font="default" size="100%">Kuusinen, Mikko</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">High cyanobiont selectivity of epiphytic lichens in old growth boreal forest of Finland.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">173</style></volume><pages><style face="normal" font="default" size="100%">621-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Here, cyanobiont selectivity of epiphytic lichen species was examined in an old growth forest area in Finland. Samples of the eight lichen species were collected from the same aspen (Populus tremula) and adjacent aspens in the same stand. The cyanobionts of these samples were compared with free and symbiotic Nostoc obtained from other habitats and geographic regions. Our results, based on the phylogenetic analysis of a partial small subunit of the ribosomal DNA (16S rDNA) and the rbcLX gene complex did not show any correlation with the geographic origin of the samples at any spatial scale. Instead, there was a correlation between the cyanobionts and the alleged taxonomy of their mycobionts. The results indicate that the lichen species examined are highly selective towards their cyanobiont partners. Only Lobaria pulmonaria proved to be more flexible, being able to associate with a wide range of Nostoc. A same Nostoc strain was found to form associations with taxonomically unrelated lichens indicating that the cyanobiont-mycobiont associations as a whole were not highly specific in the examined species.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17244057?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">López, Mónica Fajardo</style></author><author><style face="normal" font="default" size="100%">Männer, Philipp</style></author><author><style face="normal" font="default" size="100%">Willmann, Anita</style></author><author><style face="normal" font="default" size="100%">Hampp, Rüdiger</style></author><author><style face="normal" font="default" size="100%">Nehls, Uwe</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Increased trehalose biosynthesis in Hartig net hyphae of ectomycorrhizas.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">174</style></volume><pages><style face="normal" font="default" size="100%">389-98</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">To obtain photoassimilates in ectomycorrhizal symbiosis, the fungus has to create a strong sink, for example, by conversion of plant-derived hexoses into fungus-specific compounds. Trehalose is present in large quantities in Amanita muscaria and may thus constitute an important carbon sink. In Amanita muscaria-poplar (Populus tremula x tremuloides) ectomycorrhizas, the transcript abundances of genes encoding key enzymes of fungal trehalose biosynthesis, namely trehalose-6-phosphate synthase (TPS), trehalose-6-phosphate phosphatase (TPP) and trehalose phosphorylase (TP), were increased. When mycorrhizas were separated into mantle and Hartig net, TPS, TPP and TP expression was specifically enhanced in Hartig net hyphae. Compared with the extraradical mycelium, TPS and TPP expression was only slightly increased in the fungal sheath, while the increase in the expression of TP was more pronounced. TPS enzyme activity was also elevated in Hartig net hyphae, displaying a direct correlation between transcript abundance and turnover rate. In accordance with enhanced gene expression and TPS activity, trehalose content was 2.7 times higher in the Hartig net. The enhanced trehalose biosynthesis at the plant-fungus interface indicates that trehalose is a relevant carbohydrate sink in symbiosis. As sugar and nitrogen supply affected gene expression only slightly, the strongly increased expression of the investigated genes in mycorrhizas is presumably developmentally regulated.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17388901?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Barron-Gafford, Greg A</style></author><author><style face="normal" font="default" size="100%">Grieve, Katherine A</style></author><author><style face="normal" font="default" size="100%">Murthy, Ramesh</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Leaf- and stand-level responses of a forested mesocosm to independent manipulations of temperature and vapor pressure deficit.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">174</style></volume><pages><style face="normal" font="default" size="100%">614-25</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Alterations in temperature (T) and vapor pressure deficit (VPD) strongly influence gas exchange, but because VPD is highly influenced by T, the effects of these two factors are difficult to separate. Here, the concomitant effects of T and VPD on CO(2) uptake, stomatal conductance, and transpiration at leaf- and canopy-levels were examined for a stand of trees (Populus deltoides) enclosed within large mesocosms. T and VPD were independently altered to yield a factorial combination of treatments of low (24 degrees C) or high (30 degrees C) T and low (0.75) or high (1.75 kPa) VPD. Traditional leaf-level gas exchange measurements were compared with whole-canopy exchange to verify typical scaling methods. Elevated T resulted in an average 40% and 14% increase in midday leaf-level and canopy-level net CO(2) uptake, respectively. Other physiological responses to elevated T and VPD were similar at both scales, but the magnitude of change was usually less pronounced at the canopy-level. Surprisingly, only minimal interactions between T and VPD were found to influence responses of CO(2) uptake and stomatal conductance at either level.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17447916?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Dluzniewska, P</style></author><author><style face="normal" font="default" size="100%">Gessler, A</style></author><author><style face="normal" font="default" size="100%">Dietrich, H</style></author><author><style face="normal" font="default" size="100%">Schnitzler, J-P</style></author><author><style face="normal" font="default" size="100%">Teuber, M</style></author><author><style face="normal" font="default" size="100%">Rennenberg, H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Nitrogen uptake and metabolism in Populus x canescens as affected by salinity.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">173</style></volume><pages><style face="normal" font="default" size="100%">279-93</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">External salinization can affect different steps of nitrogen (N) metabolism (ion uptake, N assimilation, and amino acid and protein synthesis) depending on the inorganic N source. Here, we assessed the net uptake of N supplied as nitrate or ammonium and N assimilation (combining metabolite analyses with molecular biological approaches) in grey poplar (Populus x canescens) plants grown under saline (75 mM NaCl) and control conditions. The specific (micromol N g(-1) dry weight fine roots h(-1)) and total plant (micromol N per plant h(-1)) N net uptake rates, total plant N content, total plant biomass and total leaf protein concentration were reduced under saline conditions when plants were supplied with ammonium. In both nutritional groups, salt treatment caused pronounced accumulation of soluble N compounds in the leaves. The mRNAs of genes coding for enzymes catalyzing rate-limiting steps of both proline synthesis and degradation (delta-1-pyrroline-5-carboxylate synthase and proline dehydrogenase) as well as for NADH-dependent glutamate synthase were accumulated under saline conditions. Whereas under control conditions the plant N status seemed to be superior when ammonium was supplied, the N balance of ammonium-fed plants was more severely affected by salt stress than that of plants supplied with nitrate. Possible metabolic implications of stress-related accumulation of particular amino acids are discussed.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17204075?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Neacsu, Madalina</style></author><author><style face="normal" font="default" size="100%">Micol, Vicente</style></author><author><style face="normal" font="default" size="100%">Pérez-Fons, Laura</style></author><author><style face="normal" font="default" size="100%">Willför, Stefan</style></author><author><style face="normal" font="default" size="100%">Holmbom, Bjarne</style></author><author><style face="normal" font="default" size="100%">Mallavia, Ricardo</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A novel antioxidant phenyl disaccharide from Populus tremula knotwood.</style></title><secondary-title><style face="normal" font="default" size="100%">Molecules (Basel, Switzerland)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Molecules</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">12</style></volume><pages><style face="normal" font="default" size="100%">205-17</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The complete characterization of two compounds obtained from the acetone extract of Populus tremula knotwood has been was achieved using LC-DAD-MS, MS/MS, IR and NMR. The new compounds were unequivocally identified as a mixture of the ester isomers of the (E) and (Z) p-coumarate of 1-O-rutinose. The isomers showed the capacity to inhibit lipid peroxidation induced by tert-butylhydroperoxide and to trap peroxyl radicals, as determined by a chemiluminescence method. These new phenyl disaccharides also showed a significant ORAC (oxygen radical absorbance capacity) value, i.e. 11.7 microM TE (Trolox Equivalents).</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17846571?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Coleman, Heather D</style></author><author><style face="normal" font="default" size="100%">Canam, Thomas</style></author><author><style face="normal" font="default" size="100%">Kang, Kyu-Young</style></author><author><style face="normal" font="default" size="100%">Ellis, David D</style></author><author><style face="normal" font="default" size="100%">Mansfield, Shawn D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Over-expression of UDP-glucose pyrophosphorylase in hybrid poplar affects carbon allocation.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of experimental botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Exp. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">58</style></volume><pages><style face="normal" font="default" size="100%">4257-68</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The effects of the over-expression of the Acetobacter xylinum UDP-glucose pyrophosphorylase (UGPase) under the control of the tandem repeat Cauliflower Mosaic Virus promoter (2x35S) on plant metabolism and growth were investigated in hybrid poplar (Populus albaxgrandidentata). Transcript levels, enzyme activity, growth parameters, leaf morphology, structural and soluble carbohydrates, and soluble metabolite levels were quantified in both transgenic and wild-type trees. Transgenic 2x35S::UGPase poplar showed impaired growth rates, displaying reduced height growth and stem diameter. Morphologically, 2x35S::UGPase trees had elongated axial shoots, and leaves that were substantially smaller in size when compared with wild-type trees at equivalent developmental stages. Biochemical analysis revealed significant increases in soluble sugar, starch, and cellulose contents, and concurrent decreases in lignin content. Lignin monomer composition was altered in favour of syringyl moieties. Detailed soluble metabolite analysis revealed that 2x35S::UGPase trees had as much as a 270-fold increase in the salicylic acid 2-O-beta-D-glucoside (SAG), a compound typically associated with the stress response. These data suggest that while it is possible to alter the allocation of carbon in favour of cellulose biosynthesis, whole plant changes result in unexpected decreases in growth and an increase in defence metabolites.</style></abstract><issue><style face="normal" font="default" size="100%">15-16</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/18182429?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Tzanakakis, V E</style></author><author><style face="normal" font="default" size="100%">Paranychianakis, N V</style></author><author><style face="normal" font="default" size="100%">Angelakis, A N</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Performance of slow rate systems for treatment of domestic wastewater.</style></title><secondary-title><style face="normal" font="default" size="100%">Water science and technology : a journal of the International Association on Water Pollution Research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Water Sci. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">55</style></volume><pages><style face="normal" font="default" size="100%">139-47</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The performance of slow rate (SR) systems in terms of treatment efficiency, environmental and health risks, and land sustainability was investigated over a three-year period in a rural community close to Iraklio, Greece. Four plant species (Acacia cyanophylla, Eucalyptus camandulensis, Populus nigra and Arundo donax) were used in order to investigate the role of vegetation in the treatment of wastewater and in biomass production. Wastewater effluent was pre-treated in a septic tank before its application to land. Applied hydraulic loading rates were based on crop water requirements which were determined separately for each plant species. The evaluation of treatment performance was accomplished by measuring COD, TKN, NH3-N, NO3-N, total and reactive P, TC and FC in soil solution samples taken at different depths (15, 30 and 60 cm). SR systems showed great potential for COD, TKN and NH4-N removal which reached 89, 90 and 94%, respectively at a depth of 15 cm. An outstanding removal was also observed for TC and FC which reached 99.99%. The concentration of both P and NO3-N in soil solution increased with the passage of time, but it was lower in winter. Despite the differences in the application rates among the SR systems planted with different plant species, the treatment efficiency was not affected. Moreover, increasing the soil depth from 15 to 60 cm had no effect on the treatment efficiency of the SR systems.</style></abstract><issue><style face="normal" font="default" size="100%">1-2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17305133?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Liberloo, Marion</style></author><author><style face="normal" font="default" size="100%">Tulva, Ingmar</style></author><author><style face="normal" font="default" size="100%">Raïm, Olaf</style></author><author><style face="normal" font="default" size="100%">Kull, Olevi</style></author><author><style face="normal" font="default" size="100%">Ceulemans, Reinhart</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Photosynthetic stimulation under long-term CO2 enrichment and fertilization is sustained across a closed Populus canopy profile (EUROFACE).</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">173</style></volume><pages><style face="normal" font="default" size="100%">537-49</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The long-term response of leaf photosynthesis to rising CO2 concentrations [CO2] depends on biochemical and morphological feedbacks. Additionally, responses to elevated [CO2] might depend on the nutrient availability and the light environment, affecting the net carbon uptake of a forest stand. After 6 yr of exposure to free-air CO2 enrichment (EUROFACE) during two rotation cycles (with fertilization during the second cycle), profiles of light, leaf characteristics and photosynthetic parameters were measured in the closed canopy of a poplar (Populus) short-rotation coppice. Net photosynthetic rate (A(growth)) was 49% higher in poplars grown in elevated [CO2], independently of the canopy position. Jmax significantly increased (15%), whereas leaf carboxylation capacity (Vcmax), leaf nitrogen (N(a)) and chlorophyll (Chl(a)) were unaffected in elevated [CO2]. Leaf mass per unit area (LMA) increased in the upper canopy. Fertilization created more leaves in the top of the crown. These results suggest that the photosynthetic stimulation by elevated [CO2] in a closed-canopy poplar coppice might be sustained in the long term. The absence of any down-regulation, given a sufficient sink capacity and nutrient availability, provides more carbon for growth and storage in this bioenergy plantation.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17244048?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hancock, Jessica E</style></author><author><style face="normal" font="default" size="100%">Loya, Wendy M</style></author><author><style face="normal" font="default" size="100%">Giardina, Christian P</style></author><author><style face="normal" font="default" size="100%">Li, Laigeng</style></author><author><style face="normal" font="default" size="100%">Chiang, Vincent L</style></author><author><style face="normal" font="default" size="100%">Pregitzer, Kurt S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Plant growth, biomass partitioning and soil carbon formation in response to altered lignin biosynthesis in Populus tremuloides.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">173</style></volume><pages><style face="normal" font="default" size="100%">732-42</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We conducted a glasshouse mesocosm study that combined (13)C isotope techniques with wild-type and transgenic aspen (Populus tremuloides) in order to examine how altered lignin biosynthesis affects plant production and soil carbon formation. Our transgenic aspen lines expressed low stem lignin concentration but normal cellulose concentration, low lignin stem concentration with high cellulose concentration or an increased stem syringyl to guaiacyl lignin ratio. Large differences in stem lignin concentration observed across lines were not observed in leaves or fine roots. Nonetheless, low lignin lines accumulated 15-17% less root C and 33-43% less new soil C than the control line. Compared with the control line, transformed aspen expressing high syringyl lignin accumulated 30% less total plant C - a result of greatly reduced total leaf area - and 70% less new soil C. These findings suggest that altered stem lignin biosynthesis in Populus may have little effect on the chemistry of fine roots or leaves, but can still have large effects on plant growth, biomass partitioning and soil C formation.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17286822?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Jansson, Stefan</style></author><author><style face="normal" font="default" size="100%">Douglas, Carl J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Populus: a model system for plant biology.</style></title><secondary-title><style face="normal" font="default" size="100%">Annual review of plant biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Annu Rev Plant Biol</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">58</style></volume><pages><style face="normal" font="default" size="100%">435-58</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">With the completion of the Populus trichocarpa genome sequence and the development of various genetic, genomic, and biochemical tools, Populus now offers many possibilities to study questions that cannot be as easily addressed in Arabidopsis and rice, the two prime model systems of plant biology and genomics. Tree-specific traits such as wood formation, long-term perennial growth, and seasonality are obvious areas of research, but research in other areas such as control of flowering, biotic interactions, and evolution of adaptive traits is enriched by adding a tree to the suite of model systems. Furthermore, the reproductive biology of Populus (a dioeceous wind-pollinated long-lived tree) offers both new possibilities and challenges in the study and analysis of natural genetic and phenotypic variation. The relatively close phylogenetic relationship of Populus to Arabidopsis in the Eurosid clade of Eudicotyledonous plants aids in comparative functional studies and comparative genomics, and has the potential to greatly facilitate studies on genome and gene family evolution in eudicots.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17280524?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Plomion, Christophe</style></author><author><style face="normal" font="default" size="100%">Lalanne, Céline</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Protein extraction from woody plants.</style></title><secondary-title><style face="normal" font="default" size="100%">Methods in molecular biology (Clifton, N.J.)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Methods Mol. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">355</style></volume><pages><style face="normal" font="default" size="100%">37-41</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In this chapter we present a protocol for total protein extraction optimized for wood-forming tissue (differentiating secondary xylem). The protocol is then used for a series of other organs (root, leaf, pollen, bud, flower, cambium, and phloem) in broadleaf (oak and poplar) and conifer (pine) species. Proteins are first extracted from tissue powdered in liquid nitrogen using the TCA-acetone method and then solubilized in an optimized buffer. The resulting 2D gels can be viewed at http://cbi.labri.fr/outils/protic/index.php.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17093300?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Brilli, Federico</style></author><author><style face="normal" font="default" size="100%">Barta, Csengele</style></author><author><style face="normal" font="default" size="100%">Fortunati, Alessio</style></author><author><style face="normal" font="default" size="100%">Lerdau, Manuel</style></author><author><style face="normal" font="default" size="100%">Loreto, Francesco</style></author><author><style face="normal" font="default" size="100%">Centritto, Mauro</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Response of isoprene emission and carbon metabolism to drought in white poplar (Populus alba) saplings.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">175</style></volume><pages><style face="normal" font="default" size="100%">244-54</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The mechanism uncoupling isoprene emission and photosynthesis under drought was investigated in Populus alba saplings. Isoprene emission, incorporation of 13C into the isoprene molecule, isoprene synthase (ISPS) activity, concentration and gene expression, and photosynthesis were measured as a function of the fraction of transpirable soil water (FTSW) and in plants recovering from drought. Photosynthesis sharply declined below FTSW30 (a FTSW of 30%) and its inhibition was not caused by metabolic factors. A decline in isoprene emission was only evident towards the FTSW endpoint. 13C incorporation into isoprene was lower when photosynthesis was constrained by drought. ISPS activity was inhibited by mild drought, while ISPS gene expression and concentration declined in concert with isoprene emission at the FTSW endpoint. Following rewatering, isoprene emission was higher than, and photosynthesis was similar to, prestress values. ISPS activity and concentration, and 13C incorporation into isoprene, also rapidly recovered to prestress values, while ISPS gene expression remained low in rewatered plants. Our experiment revealed a larger contribution of alternative carbon sources to isoprene emission only when photosynthesis was dramatically constrained by drought. Isoprene emission was likely controlled at the posttranscriptional level under severe drought.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17587373?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hüve, K</style></author><author><style face="normal" font="default" size="100%">Christ, M M</style></author><author><style face="normal" font="default" size="100%">Kleist, E</style></author><author><style face="normal" font="default" size="100%">Uerlings, R</style></author><author><style face="normal" font="default" size="100%">Niinemets, U</style></author><author><style face="normal" font="default" size="100%">Walter, A</style></author><author><style face="normal" font="default" size="100%">Wildt, J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Simultaneous growth and emission measurements demonstrate an interactive control of methanol release by leaf expansion and stomata.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of experimental botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Exp. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">58</style></volume><pages><style face="normal" font="default" size="100%">1783-93</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Emission from plants is a major source of atmospheric methanol. Growing tissues contribute most to plant-generated methanol in the atmosphere, but there is still controversy over biological and physico-chemical controls of methanol emission. Methanol as a water-soluble compound is thought to be strongly controlled by gas-phase diffusion (stomatal conductance), but growth rate can follow a different diurnal rhythm from that of stomatal conductance, and the extent to which the emission control is shared between diffusion and growth is unclear. Growth and methanol emissions from Gossypium hirsutum, Populus deltoides, and Fagus sylvatica were measured simultaneously. Methanol emission from growing leaves was several-fold higher than that from adult leaves. A pronounced diurnal rhythm of methanol emission was observed; however, this diurnal rhythm was not predominantly determined by the diurnal rhythm of leaf growth. Large methanol emission peaks in the morning when the stomata opened were observed in all species and were explained by release of methanol that had accumulated in the intercellular air space and leaf liquid pool at night in leaves with closed stomata. Cumulative daily methanol emissions were strongly correlated with the total daily leaf growth, but the diurnal rhythm of methanol emission was modified by growth rate and stomatal conductance in a complex manner. While in G. hirsutum and in F. sylvatica maxima in methanol emission and growth coincided, maximum growth rates of P. deltoides were observed at night, while maximum methanol emissions occurred in the morning. This interspecific variation was explained by differences in the share of emission control by growth processes, by stomatal conductance, and methanol solubilization in tissue water.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17374874?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Filonova, Lada</style></author><author><style face="normal" font="default" size="100%">Gunnarsson, Lavinia Cicortas</style></author><author><style face="normal" font="default" size="100%">Daniel, Geoffrey</style></author><author><style face="normal" font="default" size="100%">Ohlin, Mats</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Synthetic xylan-binding modules for mapping of pulp fibres and wood sections.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC plant biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Plant Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">7</style></volume><pages><style face="normal" font="default" size="100%">54</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The complex carbohydrate composition of natural and refined plant material is not known in detail but a matter that is of both basic and applied importance. Qualitative assessment of complex samples like plant and wood tissues requires the availability of a range of specific probes. Monoclonal antibodies and naturally existing carbohydrate binding modules (CBMs) have been used in the past to assess the presence of certain carbohydrates in plant tissues. However, the number of natural CBMs is limited and development of carbohydrate-specific antibodies is not always straightforward. We envisage the use of sets of very similar proteins specific for defined targets, like those developed by molecular evolution of a single CBM scaffold, as a suitable strategy to assess carbohydrate composition. An advantage of using synthetic CBMs lies in the possibility to study fine details of carbohydrate composition within non-uniform substrates like plant cell walls as made possible through minor differences in CBM specificity of the variety of binders that can be developed by genetic engineering.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17935619?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Fischer, Dylan G</style></author><author><style face="normal" font="default" size="100%">Hart, Stephen C</style></author><author><style face="normal" font="default" size="100%">LeRoy, Carri J</style></author><author><style face="normal" font="default" size="100%">Whitham, Thomas G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Variation in below-ground carbon fluxes along a Populus hybridization gradient.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">176</style></volume><pages><style face="normal" font="default" size="100%">415-25</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Here, soil CO(2) efflux, minirhizotron fine root production (FRP), and estimated total below-ground carbon allocation (TBCA) were examined along an elevation and hybridization gradient between two cottonwood species. FRP was 72% greater under high-elevation Populus angustifolia, but soil CO(2) efflux and TBCA were 62% and 94% greater, respectively, under low-elevation stands dominated by Populus fremontii, with a hybrid stand showing intermediate values. Differences between the responses of FRP, soil CO(2) efflux and TBCA may potentially be explained in terms of genetic controls; while plant species and hybridization explained variance in carbon flux, we found only weak correlations of FRP and TBCA with soil moisture, and no correlations with soil temperature or nitrogen availability. Soil CO(2) efflux and TBCA were uncorrelated with FRP, suggesting that, although below-ground carbon fluxes may change along environmental and genetic gradients, major components of below-ground carbon flux may be decoupled.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17888120?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Davison, Brian H</style></author><author><style face="normal" font="default" size="100%">Drescher, Sadie R</style></author><author><style face="normal" font="default" size="100%">Tuskan, Gerald A</style></author><author><style face="normal" font="default" size="100%">Davis, Mark F</style></author><author><style face="normal" font="default" size="100%">Nghiem, Nhuan P</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Variation of S/G ratio and lignin content in a Populus family influences the release of xylose by dilute acid hydrolysis.</style></title><secondary-title><style face="normal" font="default" size="100%">Applied biochemistry and biotechnology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Appl. Biochem. Biotechnol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Spring</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">129-132</style></volume><pages><style face="normal" font="default" size="100%">427-35</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Wood samples from a second generation Populus cross were shown to have different lignin contents and S/G ratios (S: syringyl-like lignin structures; G: guaiacyl-like lignin structures). The lignin contents varied from 22.7% to 25.8% and the S/G ratio from 1.8 to 2.3. Selected samples spanning these ranges were hydrolyzed with dilute (1%) sulfuric acid to release fermentable sugars. The conditions were chosen for partial hydrolysis of the hemicellulosic fraction to maximize the expression of variation among samples. The results indicated that both lignin contents and S/G ratio significantly affected the yield of xylose. For example, the xylose yield of the 25.8% lignin and 2.3 S/G (high lignin, high S/G) sample produced 30% of the theoretical yield, whereas the xylose yield of the 22.7% lignin and 1.8 S/G (low lignin, low S/G) was 55% of the theoretical value. These results indicate that lignin content and composition among genetic variants within a single species can influence the hydrolyzability of the biomass.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16915659?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kazinczi, Gabriella</style></author><author><style face="normal" font="default" size="100%">Gáspár, László</style></author><author><style face="normal" font="default" size="100%">Nyitrai, Péter</style></author><author><style face="normal" font="default" size="100%">Gáborjányi, Richard</style></author><author><style face="normal" font="default" size="100%">Sárvári, Eva</style></author><author><style face="normal" font="default" size="100%">Takács, András</style></author><author><style face="normal" font="default" size="100%">Horváth, József</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Herbicide-affected plant metabolism reduces virus propagation.</style></title><secondary-title><style face="normal" font="default" size="100%">Zeitschrift für Naturforschung. C, Journal of biosciences</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Z. Naturforsch., C, J. Biosci.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Sep-Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">61</style></volume><pages><style face="normal" font="default" size="100%">692-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">It has been previously shown that certain herbicides or plant extracts inhibited the viral infection. The goal of this study was to investigate the effect of Obuda pepper virus (ObPV) infection and herbicide or plant extract treatments on the photosynthetic processes of the host plants to get informations about the interactions of these factors. In Capsicum annuum-ObPV host-virus relations the virus infection slightly increased the activity of photosystem II (PSII), as it was supposed from fluorescence induction parameters. Chlorophyll content of leaves was also elevated probably due to virus-induced growth inhibition. The herbicide Stomp (active ingredient: pendimethalin) incorporated into the soil one week before planting (preplant treatment) together with virus infection even strengthened these effects in agreement with previous observations that this herbicide always did not prevent virus infection or reduce virus concentration in hosts. In ObPV-infected Nicotiana tabacum the structural changes showed similar tendency like in ObPV-infected C. annuum, but PSII efficiency did not significantly differ from that of the control. However, non-photochemical quenching (NPQ) increased because of the strongly decreasing CO2 fixation activity. Though simultaneous application of a water extract of Cirsium arvense shoot caused a little stronger inhibition of CO2 fixation, little loss in production was obtained due to significant reduction in virus concentration. In Solanum nigrum-ObPV relation the slightly increasing tendency of the values of actual PSII quantum efficiency could be related to the probably elevated ratio of reaction centre components (increased chlorophyll a/b ratio) in the thylakoids. Application of the herbicide Fusilade S (active ingredient: fluazifop-P-butyl) at 4-6 leaf stage as a post-emergence treatment practically prevented systemic virus infection and the virus-induced changes of photosynthesis are probably due to inhibiting the virus infection/replication process.</style></abstract><issue><style face="normal" font="default" size="100%">9-10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17139793?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Greif, Matthew D</style></author><author><style face="normal" font="default" size="100%">Gibas, Connie Fe C</style></author><author><style face="normal" font="default" size="100%">Currah, Randolph S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Leptographium piriforme sp. nov., from a taxonomically diverse collection of arthropods collected in an aspen-dominated forest in western Canada.</style></title><secondary-title><style face="normal" font="default" size="100%">Mycologia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mycologia</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Sep-Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">98</style></volume><pages><style face="normal" font="default" size="100%">771-80</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">During a survey of fungi associated with arthropods collected in a southern boreal mixed-wood forest in Alberta we obtained 29 isolates of a unique species of Leptographium. This species displayed a distinct combination of characteristics, including curved conidia on short-stipitate conidiophores, a secondary micronematous conidial state, stalked pear-shaped cells and an optimal growth rate at 35 C, and is described as Leptographium piriforme sp. nov. The isolates were most similar morphologically to L. crassivaginatum, but ITS sequence comparisons indicate that our isolates cannot be assigned to this or any other sequenced species in the genus. Initial observations on the pear-shaped cells in feeding experiments with Sancassania berlesei show that these structures may act as a nutritional incentive for visiting arthropods. Most arthropods carrying this new species were caught in traps baited with dung which, in light of its optimum growth temperature, suggests a coprophilous phase in the life cycle of this species. Additional isolates from woody species typical of the survey area might clarify whether Leptographium piriforme in its forest habitat occurs as a plant pathogen or saprobe.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17256580?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wang, Wang-Xia</style></author><author><style face="normal" font="default" size="100%">Dgany, Or</style></author><author><style face="normal" font="default" size="100%">Wolf, Sharon Grayer</style></author><author><style face="normal" font="default" size="100%">Levy, Ilan</style></author><author><style face="normal" font="default" size="100%">Algom, Rachel</style></author><author><style face="normal" font="default" size="100%">Pouny, Yehonathan</style></author><author><style face="normal" font="default" size="100%">Wolf, Amnon</style></author><author><style face="normal" font="default" size="100%">Marton, Ira</style></author><author><style face="normal" font="default" size="100%">Altman, Arie</style></author><author><style face="normal" font="default" size="100%">Shoseyov, Oded</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Aspen SP1, an exceptional thermal, protease and detergent-resistant self-assembled nano-particle.</style></title><secondary-title><style face="normal" font="default" size="100%">Biotechnology and bioengineering</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biotechnol. Bioeng.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Sep 5</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">95</style></volume><pages><style face="normal" font="default" size="100%">161-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Stable protein 1 (SP1) is a homo-oligomeric protein isolated from aspen (Populus tremula aspen) plants which forms a ring-shape dodecameric particle with a central cavity. The oligomeric form of SP1 is an exceptionally stable structure that is resistant to proteases (e.g., trypsin, V8, and proteinase K), high temperatures, organic solvents, and high levels of ionic detergent. Analytical ultra-centrifugation, chemical cross-linking, matrix-assisted laser-desorption time-of-flight mass spectrometry (MALDI-TOF-MS), and transmission electron microscopy were used to further characterize the SP1 dodecamer. Introduction of a single cysteine at the N-terminus of SP1 enabled the formation of disulfide bridges within the SP1 dodecamer, concurrent with increased melting point. A six-histidine tag was introduced at the N-terminus of SP1 to generate 6HSP1, and the DeltaNSP1 mutant was generated by a deletion of amino acids 2-6 at the N-terminus. Both 6HSP1 and DeltaNSP1 maintained their ability to assemble a stable dodecamer. Remarkably, these SP1 homo-dodecamers were able to re-assemble into stable hetero-dodecamers following co-electro-elution from SDS-PAGE. The exceptional stability of the SP1-nano ring and its ability to self-assemble hetero-complexes paves the way to further research in utilizing this unique protein in nano-biotechnology.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16732592?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Acar, Filiz Nuran</style></author><author><style face="normal" font="default" size="100%">Eren, Zeynep</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Removal of Cu(II) ions by activated poplar sawdust (Samsun clone) from aqueous solutions.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of hazardous materials</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Hazard. Mater.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Sep 21</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">137</style></volume><pages><style face="normal" font="default" size="100%">909-14</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In this work, adsorption of Cu(II) ions on sawdust (SD) and activated sawdust (ASD) has been studied by using batch adsorption techniques. The equilibrium adsorption level was determined to be a function of the pH, initial Cu(II) concentration, and adsorbent dosage. The equilibrium nature of Cu(II) adsorption has been described by the Freundlich and Langmuir isotherms. The experimental adsorption data were fitted to the Langmuir adsorption model both sawdust and activated sawdust. The equilibrium capacity of sawdust and activated sawdust were 5.432 and 13.495 mg copper per g adsorbent, respectively at room temperature and natural pH. The maximum adsorption capacity was obtained at the maximum zeta potential value that -74.5 mV (pH 5) for activated sawdust and at -48.4 mV (pH 4) for sawdust. It was observed that activated sawdust was a suitable adsorbent than sawdust for removal of Cu(II) from aqueous solutions.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16621263?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Tuskan, G A</style></author><author><style face="normal" font="default" size="100%">Difazio, S</style></author><author><style face="normal" font="default" size="100%">Jansson, S</style></author><author><style face="normal" font="default" size="100%">Bohlmann, J</style></author><author><style face="normal" font="default" size="100%">Grigoriev, I</style></author><author><style face="normal" font="default" size="100%">Hellsten, U</style></author><author><style face="normal" font="default" size="100%">Putnam, N</style></author><author><style face="normal" font="default" size="100%">Ralph, S</style></author><author><style face="normal" font="default" size="100%">Rombauts, S</style></author><author><style face="normal" font="default" size="100%">Salamov, A</style></author><author><style face="normal" font="default" size="100%">Schein, J</style></author><author><style face="normal" font="default" size="100%">Sterck, L</style></author><author><style face="normal" font="default" size="100%">Aerts, A</style></author><author><style face="normal" font="default" size="100%">Bhalerao, R R</style></author><author><style face="normal" font="default" size="100%">Bhalerao, R P</style></author><author><style face="normal" font="default" size="100%">Blaudez, D</style></author><author><style face="normal" font="default" size="100%">Boerjan, W</style></author><author><style face="normal" font="default" size="100%">Brun, A</style></author><author><style face="normal" font="default" size="100%">Brunner, A</style></author><author><style face="normal" font="default" size="100%">Busov, V</style></author><author><style face="normal" font="default" size="100%">Campbell, M</style></author><author><style face="normal" font="default" size="100%">Carlson, J</style></author><author><style face="normal" font="default" size="100%">Chalot, M</style></author><author><style face="normal" font="default" size="100%">Chapman, J</style></author><author><style face="normal" font="default" size="100%">Chen, G-L</style></author><author><style face="normal" font="default" size="100%">Cooper, D</style></author><author><style face="normal" font="default" size="100%">Coutinho, P M</style></author><author><style face="normal" font="default" size="100%">Couturier, J</style></author><author><style face="normal" font="default" size="100%">Covert, S</style></author><author><style face="normal" font="default" size="100%">Cronk, Q</style></author><author><style face="normal" font="default" size="100%">Cunningham, R</style></author><author><style face="normal" font="default" size="100%">Davis, J</style></author><author><style face="normal" font="default" size="100%">Degroeve, S</style></author><author><style face="normal" font="default" size="100%">Déjardin, A</style></author><author><style face="normal" font="default" size="100%">Depamphilis, C</style></author><author><style face="normal" font="default" size="100%">Detter, J</style></author><author><style face="normal" font="default" size="100%">Dirks, B</style></author><author><style face="normal" font="default" size="100%">Dubchak, I</style></author><author><style face="normal" font="default" size="100%">Duplessis, S</style></author><author><style face="normal" font="default" size="100%">Ehlting, J</style></author><author><style face="normal" font="default" size="100%">Ellis, B</style></author><author><style face="normal" font="default" size="100%">Gendler, K</style></author><author><style face="normal" font="default" size="100%">Goodstein, D</style></author><author><style face="normal" font="default" size="100%">Gribskov, M</style></author><author><style face="normal" font="default" size="100%">Grimwood, J</style></author><author><style face="normal" font="default" size="100%">Groover, A</style></author><author><style face="normal" font="default" size="100%">Gunter, L</style></author><author><style face="normal" font="default" size="100%">Hamberger, B</style></author><author><style face="normal" font="default" size="100%">Heinze, B</style></author><author><style face="normal" font="default" size="100%">Helariutta, Y</style></author><author><style face="normal" font="default" size="100%">Henrissat, B</style></author><author><style face="normal" font="default" size="100%">Holligan, D</style></author><author><style face="normal" font="default" size="100%">Holt, R</style></author><author><style face="normal" font="default" size="100%">Huang, W</style></author><author><style face="normal" font="default" size="100%">Islam-Faridi, N</style></author><author><style face="normal" font="default" size="100%">Jones, S</style></author><author><style face="normal" font="default" size="100%">Jones-Rhoades, M</style></author><author><style face="normal" font="default" size="100%">Jorgensen, R</style></author><author><style face="normal" font="default" size="100%">Joshi, C</style></author><author><style face="normal" font="default" size="100%">Kangasjärvi, J</style></author><author><style face="normal" font="default" size="100%">Karlsson, J</style></author><author><style face="normal" font="default" size="100%">Kelleher, C</style></author><author><style face="normal" font="default" size="100%">Kirkpatrick, R</style></author><author><style face="normal" font="default" size="100%">Kirst, M</style></author><author><style face="normal" font="default" size="100%">Kohler, A</style></author><author><style face="normal" font="default" size="100%">Kalluri, U</style></author><author><style face="normal" font="default" size="100%">Larimer, F</style></author><author><style face="normal" font="default" size="100%">Leebens-Mack, J</style></author><author><style face="normal" font="default" size="100%">Leplé, J-C</style></author><author><style face="normal" font="default" size="100%">Locascio, P</style></author><author><style face="normal" font="default" size="100%">Lou, Y</style></author><author><style face="normal" font="default" size="100%">Lucas, S</style></author><author><style face="normal" font="default" size="100%">Martin, F</style></author><author><style face="normal" font="default" size="100%">Montanini, B</style></author><author><style face="normal" font="default" size="100%">Napoli, C</style></author><author><style face="normal" font="default" size="100%">Nelson, D R</style></author><author><style face="normal" font="default" size="100%">Nelson, C</style></author><author><style face="normal" font="default" size="100%">Nieminen, K</style></author><author><style face="normal" font="default" size="100%">Nilsson, O</style></author><author><style face="normal" font="default" size="100%">Pereda, V</style></author><author><style face="normal" font="default" size="100%">Peter, G</style></author><author><style face="normal" font="default" size="100%">Philippe, R</style></author><author><style face="normal" font="default" size="100%">Pilate, G</style></author><author><style face="normal" font="default" size="100%">Poliakov, A</style></author><author><style face="normal" font="default" size="100%">Razumovskaya, J</style></author><author><style face="normal" font="default" size="100%">Richardson, P</style></author><author><style face="normal" font="default" size="100%">Rinaldi, C</style></author><author><style face="normal" font="default" size="100%">Ritland, K</style></author><author><style face="normal" font="default" size="100%">Rouzé, P</style></author><author><style face="normal" font="default" size="100%">Ryaboy, D</style></author><author><style face="normal" font="default" size="100%">Schmutz, J</style></author><author><style face="normal" font="default" size="100%">Schrader, J</style></author><author><style face="normal" font="default" size="100%">Segerman, B</style></author><author><style face="normal" font="default" size="100%">Shin, H</style></author><author><style face="normal" font="default" size="100%">Siddiqui, A</style></author><author><style face="normal" font="default" size="100%">Sterky, F</style></author><author><style face="normal" font="default" size="100%">Terry, A</style></author><author><style face="normal" font="default" size="100%">Tsai, C-J</style></author><author><style face="normal" font="default" size="100%">Uberbacher, E</style></author><author><style face="normal" font="default" size="100%">Unneberg, P</style></author><author><style face="normal" font="default" size="100%">Vahala, J</style></author><author><style face="normal" font="default" size="100%">Wall, K</style></author><author><style face="normal" font="default" size="100%">Wessler, S</style></author><author><style face="normal" font="default" size="100%">Yang, G</style></author><author><style face="normal" font="default" size="100%">Yin, T</style></author><author><style face="normal" font="default" size="100%">Douglas, C</style></author><author><style face="normal" font="default" size="100%">Marra, M</style></author><author><style face="normal" font="default" size="100%">Sandberg, G</style></author><author><style face="normal" font="default" size="100%">Van de Peer, Y</style></author><author><style face="normal" font="default" size="100%">Rokhsar, D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The genome of black cottonwood, Populus trichocarpa (Torr. &amp; Gray).</style></title><secondary-title><style face="normal" font="default" size="100%">Science (New York, N.Y.)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Science</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Sep 15</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">313</style></volume><pages><style face="normal" font="default" size="100%">1596-604</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We report the draft genome of the black cottonwood tree, Populus trichocarpa. Integration of shotgun sequence assembly with genetic mapping enabled chromosome-scale reconstruction of the genome. More than 45,000 putative protein-coding genes were identified. Analysis of the assembled genome revealed a whole-genome duplication event; about 8000 pairs of duplicated genes from that event survived in the Populus genome. A second, older duplication event is indistinguishably coincident with the divergence of the Populus and Arabidopsis lineages. Nucleotide substitution, tandem gene duplication, and gross chromosomal rearrangement appear to proceed substantially more slowly in Populus than in Arabidopsis. Populus has more protein-coding genes than Arabidopsis, ranging on average from 1.4 to 1.6 putative Populus homologs for each Arabidopsis gene. However, the relative frequency of protein domains in the two genomes is similar. Overrepresented exceptions in Populus include genes associated with lignocellulosic wall biosynthesis, meristem development, disease resistance, and metabolite transport.</style></abstract><issue><style face="normal" font="default" size="100%">5793</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16973872?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Stokstad, Erik</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genomics. Poplar tree sequence yields genome double take.</style></title><secondary-title><style face="normal" font="default" size="100%">Science (New York, N.Y.)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Science</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Sep 15</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">313</style></volume><pages><style face="normal" font="default" size="100%">1556</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">5793</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16973849?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ohlsson, Anna B</style></author><author><style face="normal" font="default" size="100%">Djerbi, Soraya</style></author><author><style face="normal" font="default" size="100%">Winzell, Anders</style></author><author><style face="normal" font="default" size="100%">Bessueille, Laurence</style></author><author><style face="normal" font="default" size="100%">Ståldal, Veronika</style></author><author><style face="normal" font="default" size="100%">Li, Xinguo</style></author><author><style face="normal" font="default" size="100%">Blomqvist, Kristina</style></author><author><style face="normal" font="default" size="100%">Bulone, Vincent</style></author><author><style face="normal" font="default" size="100%">Teeri, Tuula T</style></author><author><style face="normal" font="default" size="100%">Berglund, Torkel</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Cell suspension cultures of Populus tremula x P. tremuloides exhibit a high level of cellulose synthase gene expression that coincides with increased in vitro cellulose synthase activity.</style></title><secondary-title><style face="normal" font="default" size="100%">Protoplasma</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Protoplasma</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">228</style></volume><pages><style face="normal" font="default" size="100%">221-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Compared to wood, cell suspension cultures provide convenient model systems to study many different cellular processes in plants. Here we have established cell suspension cultures of Populus tremula L. x P. tremuloides Michx. and characterized them by determining the enzymatic activities and/or mRNA expression levels of selected cell wall-specific proteins at the different stages of growth. While enzymes and proteins typically associated with primary cell wall synthesis and expansion were detected in the exponential growth phase of the cultures, the late stationary phase showed high expression of the secondary-cell-wall-associated cellulose synthase genes. Interestingly, detergent extracts of membranes from aging cell suspension cultures exhibited high levels of in vitro cellulose synthesis. The estimated ratio of cellulose to callose was as high as 50 : 50, as opposed to the ratio of 30 : 70 so far achieved with membrane preparations extracted from other systems. The increased cellulose synthase activity was also evidenced by higher levels of Calcofluor white binding in the cell material from the stationary-phase cultures. The ease of handling cell suspension cultures and the improved capacity for in vitro cellulose synthesis suggest that these cultures offer a new basis for studying the mechanism of cellulose biosynthesis.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16838081?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rae, A M</style></author><author><style face="normal" font="default" size="100%">Ferris, Rachel</style></author><author><style face="normal" font="default" size="100%">Tallis, M J</style></author><author><style face="normal" font="default" size="100%">Taylor, Gail</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Elucidating genomic regions determining enhanced leaf growth and delayed senescence in elevated CO2.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">1730-41</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Limited information is available on the genetic variation and control for plant growth response to elevated CO(2) (e[CO(2)]). Such information is necessary to understand plant adaptation and evolution in future rising CO(2). Here, quantitative trait loci (QTL) for leaf growth, development, quality and leaf senescence were determined in a tree pedigree - an F(2) hybrid of Populus trichocarpa T. &amp; G and Populus deltoides Marsh, following season-long exposure to either current day ambient carbon dioxide (a[CO(2)]) or e[CO(2)] at 600 microL L(-1). Leaf growth and development differed between the grandparents such that P. trichocarpa showed greater response to e[CO(2)]. In the F(2) generation, leaf development and quality traits including leaf area, leaf shape, epidermal cell area, and stomatal number, specific leaf area (SLA), and the phenology trait, canopy senescence index, were sensitive to e[CO(2)]. Sixty-nine QTL were mapped for the 19 traits of plants in a[CO(2)] while 60 QTL were mapped for plants in e[CO(2)]. The results suggest that although many QTL mapped to common positions in a[CO(2)] and e[CO(2)], confirming their importance in determining growth, there was also differential genetic control for a number of traits including leaf senescence. Candidate genes were shown to collocate to regions where response QTL mapped. This study is the first to identify candidate genes that may be important in determining plant adaptation to future high-CO(2) world.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16913862?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Navrot, Nicolas</style></author><author><style face="normal" font="default" size="100%">Gelhaye, Eric</style></author><author><style face="normal" font="default" size="100%">Jacquot, Jean-Pierre</style></author><author><style face="normal" font="default" size="100%">Rouhier, Nicolas</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Identification of a new family of plant proteins loosely related to glutaredoxins with four CxxC motives.</style></title><secondary-title><style face="normal" font="default" size="100%">Photosynthesis research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Photosyn. Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">89</style></volume><pages><style face="normal" font="default" size="100%">71-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The annotation of the recently released Populus trichocarpa genome, has allowed us to characterize extensively the multigenic families of the redoxin proteins. Proteins with two cysteines separated by two amino acids (CxxC motif) are often involved in redox reactions by promoting the formation, reduction or isomerization of disulfide bonds or by binding prosthetic groups or metals. We report here the presence of a new protein family in higher plants, constituted of 19 members in Populus trichocarpa, 15 in Arabidopsis thaliana and 17 in Oryza sativa. These proteins are almost specific to higher plants, with only two homologous genes found in mammals and arthropoda but none in other kingdoms. While these proteins were predicted as glutaredoxin-like proteins (GRL) in the automatic annotation procedure, they do not share the major conserved features of glutaredoxins but instead they display four conserved CxxC motives. A classification of these proteins, based on sequence similarity, gene structure and predicted cellular localization is proposed. The expression of these genes was also investigated by analyzing EST databases and Arabidopsis microarray results.</style></abstract><issue><style face="normal" font="default" size="100%">2-3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16915354?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Weber, Richard W</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Lombardy poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Annals of allergy, asthma &amp; immunology : official publication of the American College of Allergy, Asthma, &amp; Immunology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ann. Allergy Asthma Immunol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">97</style></volume><pages><style face="normal" font="default" size="100%">A6</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17042128?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Linkosalo, Tapio</style></author><author><style face="normal" font="default" size="100%">Häkkinen, Risto</style></author><author><style face="normal" font="default" size="100%">Hänninen, Heikki</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Models of the spring phenology of boreal and temperate trees: Is there something missing?</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">26</style></volume><pages><style face="normal" font="default" size="100%">1165-72</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">According to prevailing theory, air temperature is the main environmental factor regulating the timing of bud burst of boreal and temperate trees. Air temperature has a dual role in this regulation. First, after the cessation of growth in autumn, prolonged exposure to chilling causes rest completion, i.e., removes the physiological growth-arresting conditions inside the bud. After rest completion, prolonged exposure to warm conditions causes ontogenetic development leading to bud burst or flowering. During the past three decades, several simulation models based on chilling and forcing have been developed and tested. In recent modeling studies of the timing of bud burst in mature trees, the simpler thermal-time models that assume forcing starts on a fixed date in the spring have outperformed the chilling-forcing models. We hypothesize that this discrepancy may be due to some element missing from the chilling-forcing models. We tested two new model formulations by introducing reversing, temperature-driven elements that precede forcing and by fitting the models to seven historical time series of data of flowering and leaf bud burst of common boreal tree species. In these tests, both of the new models were generally more accurate in predicting the timing of bud burst than a classical chilling-forcing model, but less accurate than the simple thermal-time model. We therefore conclude that besides chilling, other environmental factors are involved in the regulation of the timing of bud burst. Further work is needed to determine if the regulatory factors derive from air temperature or from some other environmental condition such as changes in light conditions, like day length or night length.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16740492?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Windt, Carel W</style></author><author><style face="normal" font="default" size="100%">Vergeldt, Frank J</style></author><author><style face="normal" font="default" size="100%">de Jager, P Adrie</style></author><author><style face="normal" font="default" size="100%">van As, Henk</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">MRI of long-distance water transport: a comparison of the phloem and xylem flow characteristics and dynamics in poplar, castor bean, tomato and tobacco.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">1715-29</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We used dedicated magnetic resonance imaging (MRI) equipment and methods to study phloem and xylem transport in large potted plants. Quantitative flow profiles were obtained on a per-pixel basis, giving parameter maps of velocity, flow-conducting area and volume flow (flux). The diurnal xylem and phloem flow dynamics in poplar, castor bean, tomato and tobacco were compared. In poplar, clear diurnal differences in phloem flow profile were found, but phloem flux remained constant. In tomato, only small diurnal differences in flow profile were observed. In castor bean and tobacco, phloem flow remained unchanged. In all plants, xylem flow profiles showed large diurnal variation. Decreases in xylem flux were accompanied by a decrease in velocity and flow-conducting area. The diurnal changes in flow-conducting area of phloem and xylem could not be explained by pressure-dependent elastic changes in conduit diameter. The phloem to xylem flux ratio reflects what fraction of xylem water is used for phloem transport (Münch's counterflow). This ratio was large at night for poplar (0.19), castor bean (0.37) and tobacco (0.55), but low in tomato (0.04). The differences in phloem flow velocity between the four species, as well as within a diurnal cycle, were remarkably small (0.25-0.40 mm s(-1)). We hypothesize that upper and lower bounds for phloem flow velocity may exist: when phloem flow velocity is too high, parietal organelles may be stripped away from sieve tube walls; when sap flow is too slow or is highly variable, phloem-borne signalling could become unpredictable.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16913861?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhang, XinFeng</style></author><author><style face="normal" font="default" size="100%">Thuong, Phuong Thien</style></author><author><style face="normal" font="default" size="100%">Min, Byung-Sun</style></author><author><style face="normal" font="default" size="100%">Ngoc, Tran Minh</style></author><author><style face="normal" font="default" size="100%">Hung, Tran Manh</style></author><author><style face="normal" font="default" size="100%">Lee, Ik Soo</style></author><author><style face="normal" font="default" size="100%">Na, MinKyun</style></author><author><style face="normal" font="default" size="100%">Seong, Yeon-Hee</style></author><author><style face="normal" font="default" size="100%">Song, Kyung-Sik</style></author><author><style face="normal" font="default" size="100%">Bae, KiHwan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Phenolic glycosides with antioxidant activity from the stem bark of Populus davidiana.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of natural products</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Nat. Prod.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">69</style></volume><pages><style face="normal" font="default" size="100%">1370-3</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Phytochemical study on the EtOAc-soluble fraction of the stem bark of Populus davidiana resulted in the isolation of 10 phenolic glycosides (1-10), which were identified on the basis of physicochemical and spectroscopic analyses. Among these, three new compounds, populosides A-C (1-3), were determined to be 2-coumaroylmethyl-4-hydroxyphenyl-beta-D-glucopyranoside, 2-coumaroylmethylphenyl-beta-D-glucopyranoside, and 2-feruoylmethylphenyl-beta-D-glucopyranoside, respectively. Compounds 1-10 were tested for their radical scavenging activity against an azo radical, ABTS*+. Of these, populosides A-C (1-3), populoside (4), grandidentatin (8), salireposide (9), and coumaroyl-beta-D-glucoside (10) exhibited antioxidant activity in this assay.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16989539?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhou, Gong-Ke</style></author><author><style face="normal" font="default" size="100%">Zhong, Ruiqin</style></author><author><style face="normal" font="default" size="100%">Richardson, Elizabeth A</style></author><author><style face="normal" font="default" size="100%">Morrison, W Herbert</style></author><author><style face="normal" font="default" size="100%">Nairn, C Joseph</style></author><author><style face="normal" font="default" size="100%">Wood-Jones, Alicia</style></author><author><style face="normal" font="default" size="100%">Ye, Zheng-Hua</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The poplar glycosyltransferase GT47C is functionally conserved with Arabidopsis Fragile fiber8.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant &amp; cell physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">47</style></volume><pages><style face="normal" font="default" size="100%">1229-40</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Xylan is the major hemicellulose in dicot wood. Unraveling genes involved in the biosynthesis of xylan will be of importance in understanding the process of wood formation. In this report, we investigated the possible role of poplar GT47C, a glycosyltransferase belonging to family GT47, in the biosynthesis of xylan. PoGT47C from the hybrid poplar Populus alba x tremula exhibits 84% sequence similarity to Fragile fiber8 (FRA8), which is involved in the biosynthesis of glucuronoxylan in Arabidopsis. Phylogenetic analysis of glycosyltransferase family GT47 in the Populus trichocarpa genome revealed that GT47C is the only close homolog of FRA8. In situ hybridization showed that the PoGT47C gene was expressed in developing primary xylem, secondary xylem and phloem fibers of stems, and in developing secondary xylem of roots. Sequence analysis suggests that PoGT47C is a type II membrane protein, and study of the subcellular localization demonstrated that fluorescent protein-tagged PoGT47C was located in the Golgi. Immunolocalization with a xylan monoclonal antibody LM10 revealed a nearly complete loss of xylan signals in the secondary walls of fibers and vessels in the Arabidopsis fra8 mutant. Expression of PoGT47C in the fra8 mutant restored the secondary wall thickness and xylan content to the wild-type level. Together, these results suggest that PoGT47C is functionally conserved with FRA8 and it is probably involved in xylan synthesis during wood formation.</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16887843?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lawrence, Susan D</style></author><author><style face="normal" font="default" size="100%">Dervinis, Christopher</style></author><author><style face="normal" font="default" size="100%">Novak, Nicole</style></author><author><style face="normal" font="default" size="100%">Davis, John M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Wound and insect herbivory responsive genes in poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Biotechnology letters</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biotechnol. Lett.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">28</style></volume><pages><style face="normal" font="default" size="100%">1493-501</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Insect herbivory leads to induced resistance to subsequent infestations in plants. This is due in part to feeding-induced expression of genes that can lead to reduced palatability and/or digestibility of the plant material. We identified 57 distinct differentially expressed genes from poplars that were either infested by gypsy moth (Lymantria dispar) or mechanically wounded. Eleven highly insect-inducible genes were also found to be wound-inducible. Time course analysis revealed diverse timing of peak transcript accumulation. Sequence analysis of promoters suggested that the wound responsive elements, W and DRE, and the jasmonic acid responsive H motif, are over-represented in wound-induced poplar promoters and should be investigated further.</style></abstract><issue><style face="normal" font="default" size="100%">18</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16955355?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bhandari, Suchita</style></author><author><style face="normal" font="default" size="100%">Fujino, Takeshi</style></author><author><style face="normal" font="default" size="100%">Thammanagowda, Shiv</style></author><author><style face="normal" font="default" size="100%">Zhang, Dongyan</style></author><author><style face="normal" font="default" size="100%">Xu, Fuyu</style></author><author><style face="normal" font="default" size="100%">Joshi, Chandrashekhar P</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Xylem-specific and tension stress-responsive coexpression of KORRIGAN endoglucanase and three secondary wall-associated cellulose synthase genes in aspen trees.</style></title><secondary-title><style face="normal" font="default" size="100%">Planta</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Planta</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Sep</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">224</style></volume><pages><style face="normal" font="default" size="100%">828-37</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In nature, angiosperm trees develop tension wood on the upper side of their leaning trunks and drooping branches. Development of tension wood is one of the straightening mechanisms by which trees counteract leaning or bending of stem and resume upward growth. Tension wood is characterized by the development of a highly crystalline cellulose-enriched gelatinous layer next to the lumen of the tension wood fibers. Thus experimental induction of tension wood provides a system to understand the process of cellulose biosynthesis in trees. Since KORRIGAN endoglucanases (KOR) appear to play an important role in cellulose biosynthesis in Arabidopsis, we cloned PtrKOR, a full-length KOR cDNA from aspen xylem. Using RT-PCR, in situ hybridization, and tissue-print assays, we show that PtrKOR gene expression is significantly elevated on the upper side of the bent aspen stem in response to tension stress while KOR expression is significantly suppressed on the opposite side experiencing compression stress. Moreover, three previously reported aspen cellulose synthase genes, namely, PtrCesA1, PtrCesA2, and PtrCesA3 that are closely associated with secondary cell wall development in the xylem cells exhibited similar tension stress-responsive behavior. Our results suggest that coexpression of these four proteins is important for the biosynthesis of highly crystalline cellulose typically present in tension wood fibers. Their simultaneous genetic manipulation may lead to industrially relevant improvement of cellulose in transgenic crops and trees.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16575593?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Noguera-Mazon, Valérie</style></author><author><style face="normal" font="default" size="100%">Lemoine, Jérôme</style></author><author><style face="normal" font="default" size="100%">Walker, Olivier</style></author><author><style face="normal" font="default" size="100%">Rouhier, Nicolas</style></author><author><style face="normal" font="default" size="100%">Salvador, Arnaud</style></author><author><style face="normal" font="default" size="100%">Jacquot, Jean-Pierre</style></author><author><style face="normal" font="default" size="100%">Lancelin, Jean-Marc</style></author><author><style face="normal" font="default" size="100%">Krimm, Isabelle</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Glutathionylation induces the dissociation of 1-Cys D-peroxiredoxin non-covalent homodimer.</style></title><secondary-title><style face="normal" font="default" size="100%">The Journal of biological chemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Biol. Chem.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Oct 20</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">281</style></volume><pages><style face="normal" font="default" size="100%">31736-42</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">1-Cys peroxiredoxins (1-Cys Prxs) are antioxidant enzymes that catalyze the reduction of hydroperoxides into alcohols using a strictly conserved cysteine. 1-Cys B-Prxs, homologous to human PrxVI, were recently shown to be reactivated by glutathione S-transferase (GST) pi via the formation of a GST-Prx heterodimer and Prx glutathionylation. In contrast, 1-Cys D-Prxs, homologous to human PrxV, are reactivated by the glutaredoxin-glutathione system through an unknown mechanism. To investigate the mechanistic events that mediate the 1-Cys D-Prx regeneration, interaction of the Prx with glutathione was studied by mass spectrometry and NMR. This work reveals that the Prx can be glutathionylated on its active site cysteine. Evidences are reported that the glutathionylation of 1-Cys D-Prx induces the dissociation of the Prx non-covalent homodimer, which can be recovered by reduction with dithiothreitol. This work demonstrates for the first time the existence of a redox-dependent dimer-monomer switch in the Prx family, similar to the decamer-dimer switch for the 2-Cys Prxs.</style></abstract><issue><style face="normal" font="default" size="100%">42</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16916801?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rehill, Brian J</style></author><author><style face="normal" font="default" size="100%">Whitham, Thomas G</style></author><author><style face="normal" font="default" size="100%">Martinsen, Gregory D</style></author><author><style face="normal" font="default" size="100%">Schweitzer, Jennifer A</style></author><author><style face="normal" font="default" size="100%">Bailey, Joseph K</style></author><author><style face="normal" font="default" size="100%">Lindroth, Richard L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Developmental trajectories in cottonwood phytochemistry.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of chemical ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Chem. Ecol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">32</style></volume><pages><style face="normal" font="default" size="100%">2269-85</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We examined the hypothesis that ecologically important phytochemical traits differ predictably among various developmental zones of trees (i.e., mature and juvenile zones of individual trees and juvenile ramets that sprout from roots) and that the slope of this phytochemical gradient represents a &quot;developmental trajectory.&quot; We focused on Populus fremontii (Fremont cottonwood), P. angustifolia (narrowleaf cottonwood), and their natural hybrids. Two major patterns emerged. First, within narrowleaf and hybrids, concentrations of important phytochemicals (condensed tannins and phenolic glycosides) differ greatly and predictably between developmental zones. Second, developmental trajectories differ greatly among these cottonwood species and their hybrids: Fremont exhibits a flat trajectory, narrowleaf a steep trajectory, and hybrids an intermediate trajectory, suggesting an additive genetic component and an ontogenetic basis to this phytochemical variation. Because diverse herbivorous species respond to the phytochemistry of their host plants, we predict that the developmental trajectories of plants play a major role in mediating ecological interactions and structuring communities, and that biodiversity in a stand of trees is determined by both interplant genetic diversity and intraplant ontogenetic diversity.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17001533?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Fischer, D G</style></author><author><style face="normal" font="default" size="100%">Hart, S C</style></author><author><style face="normal" font="default" size="100%">Rehill, B J</style></author><author><style face="normal" font="default" size="100%">Lindroth, R L</style></author><author><style face="normal" font="default" size="100%">Keim, P</style></author><author><style face="normal" font="default" size="100%">Whitham, T G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Do high-tannin leaves require more roots?</style></title><secondary-title><style face="normal" font="default" size="100%">Oecologia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Oecologia</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">149</style></volume><pages><style face="normal" font="default" size="100%">668-75</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The well-known deceleration of nitrogen (N) cycling in the soil resulting from addition of large amounts of foliar condensed tannins may require increased fine-root growth in order to meet plant demands for N. We examined correlations between fine-root production, plant genetics, and leaf secondary compounds in Populus angustifolia, P. fremontii, and their hybrids. We measured fine-root (&lt;2 mm) production and leaf chemistry along an experimental genetic gradient where leaf litter tannin concentrations are genetically based and exert strong control on net N mineralization in the soil. Fine-root production was highly correlated with leaf tannins and individual tree genetic composition based upon genetic marker estimates, suggesting potential genetic control of compensatory root growth in response to accumulation of foliar secondary compounds in soils. We suggest, based on previous studies in our system and the current study, that genes for tannin production could link foliar chemistry and root growth, which may provide a powerful setting for external feedbacks between above- and belowground processes.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16804703?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Okumura, Satoru</style></author><author><style face="normal" font="default" size="100%">Sawada, Machiko</style></author><author><style face="normal" font="default" size="100%">Park, Yong Woo</style></author><author><style face="normal" font="default" size="100%">Hayashi, Takahisa</style></author><author><style face="normal" font="default" size="100%">Shimamura, Masaki</style></author><author><style face="normal" font="default" size="100%">Takase, Hisabumi</style></author><author><style face="normal" font="default" size="100%">Tomizawa, Ken-Ichi</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Transformation of poplar (Populus alba) plastids and expression of foreign proteins in tree chloroplasts.</style></title><secondary-title><style face="normal" font="default" size="100%">Transgenic research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Transgenic Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">15</style></volume><pages><style face="normal" font="default" size="100%">637-46</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Plastid transformation offers several unique advantages compared with nuclear genome transformation, such as high level of transgene expression within plastids, expressing multiple transgenes as operons, lack of position effect due to site-specific transgene integration, and reducing risks of gene flow via pollen due to maternal inheritance of the plastid genome. Plastid transformation has been applied to several herbal species, but as yet there are no applications to tree species. We report here the first successful plastid transformation in a tree species, Populus alba. A vector for plastid transformation of poplar (Populus alba) was constructed, which carried the spectinomycin resistance gene and the green fluorescence protein gene as marker genes. In the regenerated shoots, the site-specific integration of foreign genes and the establishment of a high homoplastomic state were confirmed. Immunoblot analysis and histological observations corroborated the accumulation of green fluorescence protein in chloroplasts. The establishment of a plastid transformation system in poplar provides a novel tool for tree biotechnology.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16952016?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Vecchio, Stefano</style></author><author><style face="normal" font="default" size="100%">Luciano, Giorgio</style></author><author><style face="normal" font="default" size="100%">Franceschi, Enrico</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Explorative kinetic study on the thermal degradation of five wood species for applications in the archaeological field.</style></title><secondary-title><style face="normal" font="default" size="100%">Annali di chimica</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ann Chim</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Nov-Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">96</style></volume><pages><style face="normal" font="default" size="100%">715-25</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Differential scanning calorimetry (DSC) and thermogravimetric analysis (TG) were performed on wood samples of different essences (fir, chestnut, poplar, linden and oak) before consolidation. A kinetic analysis was applied on the two-steps decomposition processes occurring in all wood samples using either the multiheating rates Kissinger equation and the isoconversional Ozawa-Flynn-Wall method that enables the variation of activation energy to be determined as a function of the degree of reaction. Taking into account both decomposition temperature and activation energy for the first degradation step oak seems to be the less stable sample. The comparison of DSC curves performed in air with those in oxygen enables to consider the role of the partial pressure of oxygen in the mechanisms of both decompositions.</style></abstract><issue><style face="normal" font="default" size="100%">11-12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17217176?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Christiernin, M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Lignin composition in cambial tissues of poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology and biochemistry : PPB / Société française de physiologie végétale</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol. Biochem.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Nov-Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">44</style></volume><pages><style face="normal" font="default" size="100%">700-6</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The cambial tissues of a Populus balsamifera, Balsam poplar clone were studied during a growth season. The Klason and acid-soluble lignin contents were determined as well as the carbohydrate monomer distribution and the protein content. Both the phloem and the xylem sides of the cambial region were examined. The samples were analyzed by thioacidolysis and structures of dimeric products were determined by mass spectrometry after desulphuration. Chemical analysis of samples during the growth season was combined with microscopy of embedded specimens that showed the state of cell differentiation at the time of sampling. In spring and early summer, growth is very rapid and the intention was to collect tissue in which exclusively the middle lamella/primary cell wall had begun to lignify. The Klason lignin, protein content and carbohydrate monomer distribution showed that all the specimens from the cambial tissues sampled during a growth season contained predominantly middle lamella and primary walls; except for the developing xylem sampled in August where the carbohydrate composition showed that secondary walls were present. Thioacidolysis showed that the lignin from the cambial tissues had more condensed structures than the lignin from the reference balsam poplar clone wood. More guaiacyl than syringyl units were detected and mass spectrometry showed that the cambial tissues contained more lignin structures with end-groups than the reference sample. These results suggest that lignification in the cambial layer and early developing xylem may take place predominantly in a bulk fashion during the summer.</style></abstract><issue><style face="normal" font="default" size="100%">11-12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17097296?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Liang, Zong-Suo</style></author><author><style face="normal" font="default" size="100%">Yang, Jian-Wei</style></author><author><style face="normal" font="default" size="100%">Shao, Hong-Bo</style></author><author><style face="normal" font="default" size="100%">Han, Rui-Lian</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Investigation on water consumption characteristics and water use efficiency of poplar under soil water deficits on the Loess Plateau.</style></title><secondary-title><style face="normal" font="default" size="100%">Colloids and surfaces. B, Biointerfaces</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Colloids Surf B Biointerfaces</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Nov 1</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">53</style></volume><pages><style face="normal" font="default" size="100%">23-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The water consumption characteristics and water use efficiency (WUE) of poplar (Populus simonii) were investigated under the condition of three different soil water regimes, which were 70%, 55% and 40% of field capacity (FC), respectively. The results showed that water potential, water content, photosynthetic rate, WUE of leaves, and plant growth rate decreased significantly with reduction in soil water content. At the level of adequate and medium soil water content, rapid growth and biomass accumulation in poplar occurred during May and June, whereas this phenomenon occurred only during May under severe soil drought condition. Total water consumption and biomass growth were the greatest under adequate soil water condition, decreased under medium soil drought condition, and lowest under severe soil drought condition. Total WUE was the highest under medium soil water condition and lowest under severe soil condition. Changing patterns of water consumption for daily rate, every 10-day rate, and month rate were quite different under these three soil water regimes. For all these three treatments, the highest monthly water consumption rate occurred during July and June. The highest water consumption over a 10-day period was during in the second 10 days of July, the first 10 days of July, and the last 10 days of June for these three treatments, respectively. The day for the highest water consumption in the medium and severe drought treatments occurred 1 or 2 months earlier than the adequate soil water treatment. The daily time for the greatest water consumption was different throughout the life span of poplar under these soil water levels. According to these results, we concluded that poplar did not have the characteristics of drought-resistance plants, and we do not recommend that this tree species be planted over a wider range of the Loess Plateau in China.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16949801?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kim, Bong-Gyu</style></author><author><style face="normal" font="default" size="100%">Kim, Hojung</style></author><author><style face="normal" font="default" size="100%">Hur, Hor-Gil</style></author><author><style face="normal" font="default" size="100%">Lim, Yoongho</style></author><author><style face="normal" font="default" size="100%">Ahn, Joong-Hoon</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Regioselectivity of 7-O-methyltransferase of poplar to flavones.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of biotechnology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Biotechnol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Nov 1</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">126</style></volume><pages><style face="normal" font="default" size="100%">241-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">POMT-7, an O-methyltransferase from poplar (Populus deltoids) was used to modify a variety of flavonoid compounds. POMT-7 was able to transfer a methyl group to several flavonoids containing a C-7 hydroxyl group. However, POMT-7 showed a higher affinity toward flavonol and flavone such as apigenin, kaempferol, luteolin, and quercetin than flavanone and isoflavone. Based on comparison of HPLC retention times with authentic compounds and corresponding nuclear magnetic resonance spectroscopy data, the methylation position of the reaction products was determined to be at the hydroxyl group of C-7. Biotransformation kinetics indicated that the enzyme converted more than 80% of the apigenin, kaempferol, luteolin and quercetin substrates, which were added at concentration of 70 microM, into corresponding 7-methoxy compounds within 24 h.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16713650?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Suzuki, Shiro</style></author><author><style face="normal" font="default" size="100%">Li, Laigeng</style></author><author><style face="normal" font="default" size="100%">Sun, Ying-Hsuan</style></author><author><style face="normal" font="default" size="100%">Chiang, Vincent L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The cellulose synthase gene superfamily and biochemical functions of xylem-specific cellulose synthase-like genes in Populus trichocarpa.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">142</style></volume><pages><style face="normal" font="default" size="100%">1233-45</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Wood from forest trees modified for more cellulose or hemicelluloses could be a major feedstock for fuel ethanol. Xylan and glucomannan are the two major hemicelluloses in wood of angiosperms. However, little is known about the genes and gene products involved in the synthesis of these wood polysaccharides. Using Populus trichocarpa as a model angiosperm tree, we report here a systematic analysis in various tissues of the absolute transcript copy numbers of cellulose synthase superfamily genes, the cellulose synthase (CesA) and the hemicellulose-related cellulose synthase-like (Csl) genes. Candidate Csl genes were characterized for biochemical functions in Drosophila Schneider 2 (S2) cells. Of the 48 identified members, 37 were found expressed in various tissues. Seven CesA genes are xylem specific, suggesting gene networks for the synthesis of wood cellulose. Four Csl genes are xylem specific, three of which belong to the CslA subfamily. The more xylem-specific CslA subfamily is represented by three types of members: PtCslA1, PtCslA3, and PtCslA5. They share high sequence homology, but their recombinant proteins produced by the S2 cells exhibited distinct substrate specificity. PtCslA5 had no catalytic activity with the substrates for xylan or glucomannan. PtCslA1 and PtCslA3 encoded mannan synthases, but PtCslA1 further encoded a glucomannan synthase for the synthesis of (1--&gt;4)-beta-D-glucomannan. The expression of PtCslA1 is most highly xylem specific, suggesting a key role for it in the synthesis of wood glucomannan. The results may help guide further studies to learn about the regulation of cellulose and hemicellulose synthesis in wood.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16950861?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Yang, Xiaohan</style></author><author><style face="normal" font="default" size="100%">Tuskan, Gerald A</style></author><author><style face="normal" font="default" size="100%">Cheng, Max Zong-Ming</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Divergence of the Dof gene families in poplar, Arabidopsis, and rice suggests multiple modes of gene evolution after duplication.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">142</style></volume><pages><style face="normal" font="default" size="100%">820-30</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">It is widely accepted that gene duplication is a primary source of genetic novelty. However, the evolutionary fate of duplicated genes remains largely unresolved. The classical Ohno's Duplication-Retention-Non/Neofunctionalization theory, and the recently proposed alternatives such as subfunctionalization or duplication-degeneration-complementation, and subneofunctionalization, each can explain one or more aspects of gene fate after duplication. Duplicated genes are also affected by epigenetic changes. We constructed a phylogenetic tree using Dof (DNA binding with one finger) protein sequences from poplar (Populus trichocarpa) Torr. &amp; Gray ex Brayshaw, Arabidopsis (Arabidopsis thaliana), and rice (Oryza sativa). From the phylogenetic tree, we identified 27 pairs of paralogous Dof genes in the terminal nodes. Analysis of protein motif structure of the Dof paralogs and their ancestors revealed six different gene fates after gene duplication. Differential protein methylation was revealed between a pair of duplicated poplar Dof genes, which have identical motif structure and similar expression pattern, indicating that epigenetics is involved in evolution. Analysis of reverse transcription-PCR, massively parallel signature sequencing, and microarray data revealed that the paralogs differ in expression pattern. Furthermore, analysis of nonsynonymous and synonymous substitution rates indicated that divergence of the duplicated genes was driven by positive selection. About one-half of the motifs in Dof proteins were shared by non-Dof proteins in the three plants species, indicating that motif co-option may be one of the forces driving gene diversification. We provided evidence that the Ohno's Duplication-Retention-Non/Neofunctionalization, subfunctionalization/duplication-degeneration-complementation, and subneofunctionalization hypotheses are complementary with, not alternative to, each other.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16980566?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hermle, Sandra</style></author><author><style face="normal" font="default" size="100%">Günthardt-Goerg, Madeleine S</style></author><author><style face="normal" font="default" size="100%">Schulin, Rainer</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Effects of metal-contaminated soil on the performance of young trees growing in model ecosystems under field conditions.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">144</style></volume><pages><style face="normal" font="default" size="100%">703-14</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Young Populus tremula, Salix viminalis, Betula pendula and Picea abies trees were grown together in large open-top chambers. The treatments were: without or with (Cu/Zn/Cd/Pb=640/3000/10/90 mg kg-1) metal contamination in the topsoil, irrigation pH 3.5 or 5.5, and acidic or calcareous subsoil. Growth, metal allocation to foliage and wood, as well as leaf gas exchange were measured. Biomass was reduced in P. tremula and B. pendula by the metal-contaminated topsoil relative to uncontaminated topsoil, whereas in P. tremula photosynthesis and transpiration were decreased. These effects were related to the elevated foliar Zn accumulation in P. tremula. S. viminalis showed a significant reduction in growth and an increased Zn and Cd accumulation on acidic vs. calcareous subsoil. Acidic irrigation produced only a few significant effects. P. abies showed the lowest metal uptake and no growth response to metal contamination.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16540218?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Moore, Fiona Porteous</style></author><author><style face="normal" font="default" size="100%">Barac, Tanja</style></author><author><style face="normal" font="default" size="100%">Borremans, Brigitte</style></author><author><style face="normal" font="default" size="100%">Oeyen, Licy</style></author><author><style face="normal" font="default" size="100%">Vangronsveld, Jaco</style></author><author><style face="normal" font="default" size="100%">van der Lelie, Daniel</style></author><author><style face="normal" font="default" size="100%">Campbell, Colin D</style></author><author><style face="normal" font="default" size="100%">Moore, Edward R B</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Endophytic bacterial diversity in poplar trees growing on a BTEX-contaminated site: the characterisation of isolates with potential to enhance phytoremediation.</style></title><secondary-title><style face="normal" font="default" size="100%">Systematic and applied microbiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Syst. Appl. Microbiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">539-56</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The diversity of endophytic bacteria found in association with poplar was investigated as part of a larger study to assess the possibility and practicality of using endophytic bacteria to enhance in situ phytoremediation. Endophytic bacteria were isolated from the root, stem and leaf of two cultivars of poplar tree growing on a site contaminated with BTEX compounds. They were further characterised genotypically by comparative sequence analysis of partial 16S rRNA genes and BOX-PCR genomic DNA fingerprinting, and phenotypically by their tolerance to a range of target pollutants, heavy metals and antibiotics. One hundred and 21 stable, morphologically distinct isolates were obtained, belonging to 21 genera, although six isolates could not be identified with confidence to a genus. The endophytic bacteria exhibited marked spatial compartmentalisation within the plant, suggesting there are likely to be species-specific and non-specific associations between bacteria and plants. A number of isolates demonstrated the ability to degrade BTEX compounds or to grow in the presence of TCE. This study demonstrates that within the diverse bacterial communities found in poplar several endophytic strains are present that have the potential to enhance phytoremediation strategies.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16919907?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bangert, R K</style></author><author><style face="normal" font="default" size="100%">Allan, G J</style></author><author><style face="normal" font="default" size="100%">Turek, R J</style></author><author><style face="normal" font="default" size="100%">Wimp, G M</style></author><author><style face="normal" font="default" size="100%">Meneses, N</style></author><author><style face="normal" font="default" size="100%">Martinsen, G D</style></author><author><style face="normal" font="default" size="100%">Keim, P</style></author><author><style face="normal" font="default" size="100%">Whitham, T G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">From genes to geography: a genetic similarity rule for arthropod community structure at multiple geographic scales.</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Ecol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">15</style></volume><pages><style face="normal" font="default" size="100%">4215-28</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We tested the hypothesis that leaf modifying arthropod communities are correlated with cottonwood host plant genetic variation from local to regional scales. Although recent studies found that host plant genetic composition can structure local dependent herbivore communities, the abiotic environment is a stronger factor than the genetic effect at increasingly larger spatial scales. In contrast to these studies we found that dependent arthropod community structure is correlated with both the cross type composition of cottonwoods and individual genotypes within local rivers up to the regional scale of 720,000 km(2) (Four Corner States region in the southwestern USA). Across this geographical extent comprising two naturally hybridizing cottonwood systems, the arthropod community follows a simple genetic similarity rule: genetically similar trees support more similar arthropod communities than trees that are genetically dissimilar. This relationship can be quantified with or without genetic data in Populus.</style></abstract><issue><style face="normal" font="default" size="100%">13</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17054514?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Song, Jingyuan</style></author><author><style face="normal" font="default" size="100%">Lu, Shanfa</style></author><author><style face="normal" font="default" size="100%">Chen, Zenn-Zong</style></author><author><style face="normal" font="default" size="100%">Lourenco, Rodrigo</style></author><author><style face="normal" font="default" size="100%">Chiang, Vincent L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genetic transformation of Populus trichocarpa genotype Nisqually-1: a functional genomic tool for woody plants.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant &amp; cell physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">47</style></volume><pages><style face="normal" font="default" size="100%">1582-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We report here the Agrobacterium-mediated genetic transformation of Nisqually-1, a Populus trichocarpa genotype whose genome was recently sequenced. Several systems were established. Internodal stem segments from vigorously growing greenhouse plants are the explants most amenable to transformation. For the most efficient system, approximately 40% of the stem segments infected with pBI121-containing Agrobacterium tumefaciens C58 produced transgenic calli, as confirmed by beta-glucuronidase (GUS) staining. The regeneration efficiency of independent transgenic plants was approximately 13%, as revealed by genomic Southern analysis. Some transgenic plants were produced in as little as 5 months after co-cultivation. This system may help to facilitate studies of gene functions in tree growth and development at a genome level.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17018558?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Street, Nathaniel Robert</style></author><author><style face="normal" font="default" size="100%">Skogström, Oskar</style></author><author><style face="normal" font="default" size="100%">Sjödin, Andreas</style></author><author><style face="normal" font="default" size="100%">Tucker, James</style></author><author><style face="normal" font="default" size="100%">Rodríguez-Acosta, Maricela</style></author><author><style face="normal" font="default" size="100%">Nilsson, Peter</style></author><author><style face="normal" font="default" size="100%">Jansson, Stefan</style></author><author><style face="normal" font="default" size="100%">Taylor, Gail</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The genetics and genomics of the drought response in Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">48</style></volume><pages><style face="normal" font="default" size="100%">321-41</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The genetic nature of tree adaptation to drought stress was examined by utilizing variation in the drought response of a full-sib second generation (F(2)) mapping population from a cross between Populus trichocarpa (93-968) and P. deltoides Bart (ILL-129) and known to be highly divergent for a vast range of phenotypic traits. We combined phenotyping, quantitative trait loci (QTL) analysis and microarray experiments to demonstrate that 'genetical genomics' can be used to provide information on adaptation at the species level. The grandparents and F(2) population were subjected to soil drying, and contrasting responses to drought across genotypes, including leaf coloration, expansion and abscission, were observed, and QTL for these traits mapped. A subset of extreme genotypes exhibiting extreme sensitivity and insensitivity to drought on the basis of leaf abscission were defined, and microarray experiments conducted on these genotypes and the grandparent species. The extreme genotype groups induced a different set of genes: 215 and 125 genes differed in their expression response between groups in control and drought, respectively, suggesting species adaptation at the gene expression level. Co-location of differentially expressed genes with drought-specific and drought-responsive QTLs was examined, and these may represent candidate genes contributing to the variation in drought response.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17005011?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Luo, Keming</style></author><author><style face="normal" font="default" size="100%">Deng, Wei</style></author><author><style face="normal" font="default" size="100%">Xiao, Yuehua</style></author><author><style face="normal" font="default" size="100%">Zheng, Xuelian</style></author><author><style face="normal" font="default" size="100%">Li, Yi</style></author><author><style face="normal" font="default" size="100%">Pei, Yan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Leaf senescence is delayed in tobacco plants expressing the maize knotted1 gene under the control of a wound-inducible promoter.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant cell reports</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Rep.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">25</style></volume><pages><style face="normal" font="default" size="100%">1246-54</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">To extend the shelf life of freshly harvested vegetables and cut flowers, a maize homeobox gene Knotted1 (kn1) was placed under the control of a wound-inducible promoter win3.12 from hybrid poplar (Populus trichocarpa x P. deltoides) and introduced into tobacco plants (Nicotiana tabacum cv. Xanthi). Transgenic win3.12::kn1 plants were morphologically normal. A leaf-detachment assay demonstrated that senescence in win3.12::kn1 leaves could be delayed by at least 2 weeks compared with wild type leaves. Furthermore, all leaves of win3.12::kn1 shoots remained green and healthy 3 weeks after excision and incubation in water, while older leaves of control shoots senesced under the same conditions. Additionally, a number of adventitious roots produced at the cut ends of wild type shoots after a 3-week incubation, but much a less number of adventitious roots appeared in win3.12::kn1 shoots. The delay in senescence was also confirmed by a higher total chlorophyll (a + b) content in win3.12::kn1 leaves relative to that of the control plants. RT-PCR analysis showed that the kn1 transcript was detected in win3.12::kn1 leaves with wounding treatment, but otherwise was not observed in leaves of wild type and unwounded transgenic plants. The results presented here indicate that expression of kn1 gene driven by the wound-inducible promoter win3.12 is potentially useful to delay senescence of vegetable crops and commercial horticulture after harvest.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16794826?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bae, Eun-Kyung</style></author><author><style face="normal" font="default" size="100%">Lee, Hyoshin</style></author><author><style face="normal" font="default" size="100%">Lee, Jae-Soon</style></author><author><style face="normal" font="default" size="100%">Noh, Eun-Woon</style></author><author><style face="normal" font="default" size="100%">Jo, Jinki</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Molecular cloning of a peroxidase gene from poplar and its expression in response to stress.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">26</style></volume><pages><style face="normal" font="default" size="100%">1405-12</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">To elucidate the precise functions of peroxidase in poplar (Populus alba x P. tremula var. glandulosa), we cloned a peroxidase gene (PoPOD1) from poplar suspension culture cells and examined its expression pattern in response to various stresses. PoPOD1 showed the highest homology with a bacterial-induced peroxidase gene from cotton (Gossypium hirsutum L.). The PoPOD1 gene encodes a putative 316 amino acid protein with an N-terminal signal peptide of 23 residues. The DNA blot analysis indicated that PoPOD1 is a single copy gene in the poplar genome. The RNA blot analyses indicated that PoPOD1 shows cell-culture-specific expression. Expression of PoPOD1 is down-regulated by various treatments including treatment with some metals, NaCl, methyl viologen and polyethylene glycol, and by the plant growth regulators, jasmonic acid (JA) and gibberellic acid (GA(3)). The gene is significantly up-regulated by the bacterial-elicitor laminarin and by wounding. Thus, PoPOD1 gene expression is sensitively and specifically regulated at the transcription level. Because both JA and GA3 appear to be involved in the regulation of PoPOD1 expression in poplar cells, we postulate that the peroxidase encoded by PoPOD1 plays a pivotal role in defense against pathogen invasion, possibly through the formation of a cell wall barrier over the wound.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16877325?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kovács, Gábor M</style></author><author><style face="normal" font="default" size="100%">Jakucs, Erzsébet</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Morphological and molecular comparison of white truffle ectomycorrhizae.</style></title><secondary-title><style face="normal" font="default" size="100%">Mycorrhiza</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mycorrhiza</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">16</style></volume><pages><style face="normal" font="default" size="100%">567-74</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In the present study, white truffle ectomycorrhizae (EM) collected in deciduous forests (Populus, Quercus, and Fagus) from Hungary were characterized by morphological-anatomical and molecular methods. Our investigations suggest that the EM of white truffles (e.g., Tuber rapaeodorum, Tuber puberulum, Tuber rufum) are common and abundant members of the forest communities in the area. The ITS sequences of 14 EM specimens and 46 additional fruitbody sequences from the GenBank were clustered into four main groups in phylogenetic analyses. In the ITS-1 region, a characteristic indel pattern was found, which supports the clades. Although our analyses indicate definite genetic distance between the groups of the phylogenetic tree, these clades do not correspond to the traditional taxons identified by fruitbody characteristics. Comparison of the ectomycorrhizae shows that neither is mycorrhizal anatomy a good tool to separate the groups, because the characters (like the epidermoid or angular mantle structure, cell wall thickness, the sape and size of cystidia) are too variable and overlap between the clades. The interspecific similarity, observed both in ectomycorrhizal and fruitbody characters, strengthen the sensu lato morpho-species concept of this group. Our study, which combines comprehensive molecular and anatomical approach to characterize and identify ectomycorrhizae of white truffles from natural samples, stress out the need of the taxonomical revision of this group.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16983567?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Fu, Shilei</style></author><author><style face="normal" font="default" size="100%">Zhou, Yong-Bin</style></author><author><style face="normal" font="default" size="100%">He, Xingyuan</style></author><author><style face="normal" font="default" size="100%">Chen, Wei</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Effects of drought stress on photosynthesis physiology of Populus pseudo-simonii].</style></title><secondary-title><style face="normal" font="default" size="100%">Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ying Yong Sheng Tai Xue Bao</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">17</style></volume><pages><style face="normal" font="default" size="100%">2016-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In this paper, the effects of drought stress simulated by PEG on the photosynthesis of Populus pseudo-simonii were monitored by gas exchange and chlorophyll fluorescence techniques. The results showed that in the early phase of drought stress, net photosynthetic rate (P(n)), transpiration rate (T(r)), stomata conductance (g(s)) , and intercellular CO2 concentration (C(i)) decreased with increasing stress, and the decrease of P(n) was mainly related to the decreased g(s). In the late phase, C(i) increased gradually, while F(v)/F(m) and F(v)/F(o) decreased significantly. POD activity increased in the early phase, but decreased in the late phase. All of these indicated that in the early phase of drought stress, stomata closure was the main factor limiting P. pseudo-simonii photosynthesis, while in the late phase, the main limiting factor was non-stomatal. A short period of drought stress induced the increase of protective enzyme activity, but a longer exposure to the stress resulted in the decrease of PS II efficiency and POD activity.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17269318?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Yu, Zhongdong</style></author><author><style face="normal" font="default" size="100%">Cao, Zhimin</style></author><author><style face="normal" font="default" size="100%">Yuan, Benben</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Genetic diversity of Melampsora larici-populina].</style></title><secondary-title><style face="normal" font="default" size="100%">Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ying Yong Sheng Tai Xue Bao</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Nov</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">17</style></volume><pages><style face="normal" font="default" size="100%">2102-6</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">By using ITS - nrDNA-RELP, ITS sequencing, and RAPD molecular marker, this paper studied the genetic diversity of 11 isolates in 5 races of Melampsora larici-populina from different regions. The results indicated that the genetic differentiation of M. larici-populina was correlated to its geographical distribution, which could be grouped into northern and western geographic populations, and the latter could be grouped into high-mountain forest ecologic type (HMF) and western plain ecologic type (WPL). The genetic differentiation of the race was not always corresponded with the pathogenic one. T test manifested that the genetic diversity of the 5 races had no statistic difference in RAPD markers, and the diversity index of HMF was 0.5172, being slightly higher than that of WPL (0.5089). The ITS sequence of ribosome DNA was strictly conservative, and not suitable for the genetic diversity study of M. larici-populina intra-species populations.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17269335?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Laureano-Perez, Lizbeth</style></author><author><style face="normal" font="default" size="100%">Dale, Bruce E</style></author><author><style face="normal" font="default" size="100%">Zhu, Li</style></author><author><style face="normal" font="default" size="100%">O'Dwyer, Jonathan P</style></author><author><style face="normal" font="default" size="100%">Holtzapple, Mark</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Statistical correlation of spectroscopic analysis and enzymatic hydrolysis of poplar samples.</style></title><secondary-title><style face="normal" font="default" size="100%">Biotechnology progress</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biotechnol. Prog.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 May-Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">22</style></volume><pages><style face="normal" font="default" size="100%">835-41</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Spectroscopic characterization of poplar wood samples with different crystallinity indices, lignin contents, and acetyl contents was performed to determine changes in the biomass spectra and the effects of these changes on the hydrolysis yield. The spectroscopic methods used were X-ray diffraction for determining cellulose crystallinity (CrI), diffuse reflectance infrared (DRIFT) for changes in C-C and C-O bonds, and fluorescence to determine lignin content. Raman spectroscopy was also used to determine its effectiveness in the determination of crystallinity and C-C and C-O bond changes in the biomass as a complement to better-known methods. Changes in spectral characteristics and crystallinity were statistically correlated with enzymatic hydrolysis results to identify and better understand the fundamental features of biomass that influence enzymatic conversion to monomeric sugars. In addition, the different spectroscopic methods were evaluated separately to determine the minimum amount of spectroscopic data needed to obtain accurate predictions. The principal component regression (PCR) model with only the DRIFT data gives the best correlation and prediction for both initial rate of hydrolysis and also the 72-h hydrolysis yield. The factor that most affects both the initial rate and the 72-h conversion is the O-H bond content of the sample, which directly relates to the breakage of structural carbohydrates into smaller molecules.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16739968?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Faustova, N M</style></author><author><style face="normal" font="default" size="100%">Faustova, M E</style></author><author><style face="normal" font="default" size="100%">Deĭneko, I P</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Antibacterial activity of aspen bark extracts against some pneumotropic microorganisms].</style></title><secondary-title><style face="normal" font="default" size="100%">Zhurnal mikrobiologii, epidemiologii, i immunobiologii</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Zh. Mikrobiol. Epidemiol. Immunobiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 May-Jun</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">3-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Extractive substances obtained from the bark of aspen (Populus tremula L.) with the use of petroleum ether (lipids I) and diethyl ether (lipids II) have exhibited high antibacterial activity with respect to Streptococcus pneumoniae and Haemophilus influenzae, causing 100% cell destruction. The minimum inhibiting concentration for S. pneumoniae has been found to be 0.5 - 50 mg/ml for lipids I and 0.0005 - 0.5 mg/ ml for lipids II, depending on the strain of bacteria. The antibacterial activity of rhytidome extracts is somewhat higher than that of phloem extracts. To suppress the growth of H. influenzae, more concentrated solutions of these extracts from 30 to 50 mg/ml are needed. Staphylococcus aureus was resistent in lipids. The action of temperature, mineral acids and alkali on lipids, as well as prolonged storage of strains in a refrigerator decreases the antibacterial activity of extracts under study.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16830580?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Böhlenius, Henrik</style></author><author><style face="normal" font="default" size="100%">Huang, Tao</style></author><author><style face="normal" font="default" size="100%">Charbonnel-Campaa, Laurence</style></author><author><style face="normal" font="default" size="100%">Brunner, Amy M</style></author><author><style face="normal" font="default" size="100%">Jansson, Stefan</style></author><author><style face="normal" font="default" size="100%">Strauss, Steven H</style></author><author><style face="normal" font="default" size="100%">Nilsson, Ove</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">CO/FT regulatory module controls timing of flowering and seasonal growth cessation in trees.</style></title><secondary-title><style face="normal" font="default" size="100%">Science (New York, N.Y.)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Science</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 May 19</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">312</style></volume><pages><style face="normal" font="default" size="100%">1040-3</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Forest trees display a perennial growth behavior characterized by a multiple-year delay in flowering and, in temperate regions, an annual cycling between growth and dormancy. We show here that the CO/FT regulatory module, which controls flowering time in response to variations in daylength in annual plants, controls flowering in aspen trees. Unexpectedly, however, it also controls the short-day-induced growth cessation and bud set occurring in the fall. This regulatory mechanism can explain the ecogenetic variation in a highly adaptive trait: the critical daylength for growth cessation displayed by aspen trees sampled across a latitudinal gradient spanning northern Europe.</style></abstract><issue><style face="normal" font="default" size="100%">5776</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16675663?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Margis, Rogerio</style></author><author><style face="normal" font="default" size="100%">Fusaro, Adriana F</style></author><author><style face="normal" font="default" size="100%">Smith, Neil A</style></author><author><style face="normal" font="default" size="100%">Curtin, Shaun J</style></author><author><style face="normal" font="default" size="100%">Watson, John M</style></author><author><style face="normal" font="default" size="100%">Finnegan, E Jean</style></author><author><style face="normal" font="default" size="100%">Waterhouse, Peter M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The evolution and diversification of Dicers in plants.</style></title><secondary-title><style face="normal" font="default" size="100%">FEBS letters</style></secondary-title><alt-title><style face="normal" font="default" size="100%">FEBS Lett.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 May 1</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">580</style></volume><pages><style face="normal" font="default" size="100%">2442-50</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Most multicellular organisms regulate developmental transitions by microRNAs, which are generated by an enzyme, Dicer. Insects and fungi have two Dicer-like genes, and many animals have only one, yet the plant, Arabidopsis, has four. Examining the poplar and rice genomes revealed that they contain five and six Dicer-like genes, respectively. Analysis of these genes suggests that plants require a basic set of four Dicer types which were present before the divergence of mono- and dicotyledonous plants ( approximately 200 million years ago), but after the divergence of plants from green algae. A fifth type of Dicer seems to have evolved in monocots.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16638569?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Davis, Mark F</style></author><author><style face="normal" font="default" size="100%">Tuskan, Gerald A</style></author><author><style face="normal" font="default" size="100%">Payne, Peggy</style></author><author><style face="normal" font="default" size="100%">Tschaplinski, Timothy J</style></author><author><style face="normal" font="default" size="100%">Meilan, Richard</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Assessment of Populus wood chemistry following the introduction of a Bt toxin gene.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">26</style></volume><pages><style face="normal" font="default" size="100%">557-64</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Unintended changes in plant physiology, anatomy and metabolism as a result of genetic engineering are a concern as more transgenic plants are commercially deployed in the ecosystem. We compared the cell wall chemical composition of three Populus lines (Populus trichocarpa Torr. &amp; A. Gray x Populus trichocarpa Bartr. ex Marsh., Populus trichocarpa x Populus nigra L. and Populus deltoides x Populus nigra) genetically modified to express the Cry3A or Cry3B2 protein of Bacillus thuringiensis (Bt) with the cell wall chemistry of non-transformed isogenic control lines. Three genetically modified clones, each represented by 10 independent transgenic lines, were analyzed by pyrolysis molecular beam mass spectrometry, gas chromatography/mass spectrometry and traditional wet chemical analytical methods to assess changes in cell wall composition. Based on the outcome of these techniques, there were no comprehensive differences in chemical composition between the transgenic and control lines for any of the studied clones.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16452069?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Shuster, S M</style></author><author><style face="normal" font="default" size="100%">Lonsdorf, E V</style></author><author><style face="normal" font="default" size="100%">Wimp, G M</style></author><author><style face="normal" font="default" size="100%">Bailey, J K</style></author><author><style face="normal" font="default" size="100%">Whitham, T G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Community heritability measures the evolutionary consequences of indirect genetic effects on community structure.</style></title><secondary-title><style face="normal" font="default" size="100%">Evolution; international journal of organic evolution</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Evolution</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">60</style></volume><pages><style face="normal" font="default" size="100%">991-1003</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The evolutionary analysis of community organization is considered a major frontier in biology. Nevertheless, current explanations for community structure exclude the effects of genes and selection at levels above the individual. Here, we demonstrate a genetic basis for community structure, arising from the fitness consequences of genetic interactions among species (i.e., interspecific indirect genetic effects or IIGEs). Using simulated and natural communities of arthropods inhabiting North American cottonwoods (Populus), we show that when species comprising ecological communities are summarized using a multivariate statistical method, nonmetric multidimensional scaling (NMDS), the resulting univariate scores can be analyzed using standard techniques for estimating the heritability of quantitative traits. Our estimates of the broad-sense heritability of arthropod communities on known genotypes of cottonwood trees in common gardens explained 56-63% of the total variation in community phenotype. To justify and help interpret our empirical approach, we modeled synthetic communities in which the number, intensity, and fitness consequences of the genetic interactions among species comprising the community were explicitly known. Results from the model suggest that our empirical estimates of broad-sense community heritability arise from heritable variation in a host tree trait and the fitness consequences of IGEs that extend from tree trait to arthropods. When arthropod traits are heritable, interspecific IGEs cause species interactions to change, and community evolution occurs. Our results have implications for establishing the genetic foundations of communities and ecosystems.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16817539?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ren, Jian</style></author><author><style face="normal" font="default" size="100%">Yao, Yinan</style></author><author><style face="normal" font="default" size="100%">Yang, Yongqing</style></author><author><style face="normal" font="default" size="100%">Korpelainen, Helena</style></author><author><style face="normal" font="default" size="100%">Junttila, Olavi</style></author><author><style face="normal" font="default" size="100%">Li, Chunyang</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Growth and physiological responses to supplemental UV-B radiation of two contrasting poplar species.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">26</style></volume><pages><style face="normal" font="default" size="100%">665-72</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We compared the growth and physiological responses of cuttings of Populus kangdingensis C. Wang et Tung and P. cathayana Rehder originating from altitudes of 3500 m and 1500 m, respectively, when exposed to three ultraviolet-B (UV-B) radiation regimes: zero UV-B, ambient (4.5 kJ m(-2) day(-1)) and twice-ambient (9 kJ m(-2) day(-1)) biologically effective UV-B radiation for one growing season, to determine if Populus trees that are adapted to contrasting UV-B habitats exhibit different tolerances to enhanced UV-B radiation. Compared with cuttings grown without UV-B radiation, twice-ambient UV-B radiation significantly decreased total biomass, total leaf area and internode length in both species, whereas root/shoot ratio, leaf number, amount of photosynthetic pigments and ascorbate peroxidase activity were unaffected. Differences in responses were also observed between the study species. Cutting height increment, total biomass, total leaf area, free proline concentration and membrane damage assessed by electrolyte leakage were significantly more affected by the twice-ambient UV-B radiation in P. cathayana than in P. kangdingensis. However, specific leaf mass, amount of UV-B absorbing compounds and superoxide dismutase and guaiacol peroxidase activities increased more with increasing UV-B radiation in P. kangdingensis than in P. cathayana, perhaps reflecting important characteristics of species with low to moderate tolerance to UV-B radiation. Overall, the results indicated that P. kangdingensis, which originates from altitudes of 3500 m, has greater tolerance to enhanced UV-B radiation than P. cathayana originating from altitudes of 1500 m.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16452080?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Matsubara, Shizue</style></author><author><style face="normal" font="default" size="100%">Hurry, Vaughan</style></author><author><style face="normal" font="default" size="100%">Druart, Nathalie</style></author><author><style face="normal" font="default" size="100%">Benedict, Catherine</style></author><author><style face="normal" font="default" size="100%">Janzik, Ingar</style></author><author><style face="normal" font="default" size="100%">Chavarría-Krauser, Andrés</style></author><author><style face="normal" font="default" size="100%">Walter, Achim</style></author><author><style face="normal" font="default" size="100%">Schurr, Ulrich</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Nocturnal changes in leaf growth of Populus deltoides are controlled by cytoplasmic growth.</style></title><secondary-title><style face="normal" font="default" size="100%">Planta</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Planta</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">223</style></volume><pages><style face="normal" font="default" size="100%">1315-28</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Growing leaves do not expand at a constant rate but exhibit pronounced diel growth rhythms. However, the mechanisms giving rise to distinct diel growth dynamics in different species are still largely unknown. As a first step towards identifying genes controlling rate and timing of leaf growth, we analysed the transcriptomes of rapidly expanding and fully expanded leaves of Populus deltoides Bartr. ex. Marsh at points of high and low expansion at night. Tissues with well defined temporal growth rates were harvested using an online growth-monitoring system based on a digital image sequence processing method developed for quantitative mapping of dicot leaf growth. Unlike plants studied previously, leaf growth in P. deltoides was characterised by lack of a base-tip gradient across the lamina, and by maximal and minimal growth at dusk and dawn, respectively. Microarray analysis revealed that the nocturnal decline in growth coincided with a concerted down-regulation of ribosomal protein genes, indicating deceleration of cytoplasmic growth. In a subsequent time-course experiment, Northern blotting and real-time RT-PCR confirmed that the ribosomal protein gene RPL12 and a cell-cycle gene H2B were down-regulated after midnight following a decrease in cellular carbohydrate concentrations. Thus, we propose that the spatio-temporal growth pattern in leaves of P. deltoides primarily arises from cytoplasmic growth whose activity increases from afternoon to midnight and thereafter decreases in this species.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16333638?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Tschaplinski, Timothy J</style></author><author><style face="normal" font="default" size="100%">Tuskan, Gerald A</style></author><author><style face="normal" font="default" size="100%">Sewell, Mitchell M</style></author><author><style face="normal" font="default" size="100%">Gebre, G Michael</style></author><author><style face="normal" font="default" size="100%">Todd, Donald E</style></author><author><style face="normal" font="default" size="100%">Pendley, Carrie D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Phenotypic variation and quantitative trait locus identification for osmotic potential in an interspecific hybrid inbred F2 poplar pedigree grown in contrasting environments.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">26</style></volume><pages><style face="normal" font="default" size="100%">595-604</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Elucidation of the mechanisms of dehydration tolerance in poplar (Populus sp.) trees will permit development of biochemical and molecular indicators to identify dehydration-tolerant genotypes during genetic selection. The objectives of this study were to characterize the degree of phenotypic variation in osmotic potential (a determinant of dehydration tolerance), determine the relationship between osmotic potential at full turgor and relative growth rate, and identify quantitative trait loci (QTL) for osmotic potential in an advanced-generation, interspecific poplar pedigree established in contrasting environments. A three-generation, sib-mated black cottonwood (Populus trichocarpa Torr. &amp; Gray) and eastern cottonwood (P. deltoides Bartr.) segregating F(2) family (Family 331) was analyzed at a dry site east of the Cascade Mountain Range (Boardman, OR) and at a wet site west of the mountains (Clatskanie, OR). At the Boardman site, 2-year-old trees (59 clones) were either irrigated everyday (wet) or every other day (dry), whereas 3- and 4-year-old trees (58 clones) at the Clatskanie site were unirrigated. At the Boardman site, the typically narrow range of osmotic potentials exhibited by grandparents and parents was greatly expanded in the F(2) population, spanning from -1.38 to -2.35 MPa under wet conditions, with a similar range under dry conditions (-1.40 to -2.15 MPa). Clones that had osmotic potentials &lt; or = -1.90 MPa generally displayed full maintenance of stem relative growth rates under dry conditions in contrast to clones with osmotic potentials that were &lt; or = -1.60 MPa, in which stem relative growth rates were reduced by an average of 38% in the dry treatment relative to the wet treatment. Although osmotic adjustments of 0.13 to 0.36 MPa were observed in nine out of 59 clones, adjustment typically occurred from relatively high baseline osmotic potentials. The range in osmotic potential at the wetter Clatskanie site at age three was higher (-1.27 to -1.84 MPa) and was further expanded the following year (-1.14 to -1.94 MPa), which had a wetter spring than the previous year, followed by a typically dry July. Seven QTL for osmotic potential were identified that each explained &gt; 7.5% of the variation in osmotic potential. Given that four clones (7%) had osmotic potentials of -2.00 MPa or less and that QTL for osmotic potential have been identified, we suggest that there are opportunities to extend the limit of dehydration tolerance in Populus.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16452073?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Mills, Tessa</style></author><author><style face="normal" font="default" size="100%">Arnold, Barbara</style></author><author><style face="normal" font="default" size="100%">Sivakumaran, Siva</style></author><author><style face="normal" font="default" size="100%">Northcott, Grant</style></author><author><style face="normal" font="default" size="100%">Vogeler, Iris</style></author><author><style face="normal" font="default" size="100%">Robinson, Brett</style></author><author><style face="normal" font="default" size="100%">Norling, Cara</style></author><author><style face="normal" font="default" size="100%">Leonil, Doris</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Phytoremediation and long-term site management of soil contaminated with pentachlorophenol (PCP) and heavy metals.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of environmental management</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Environ. Manage.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">79</style></volume><pages><style face="normal" font="default" size="100%">232-41</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Pentachlorophenol (PCP) is a persistent organic pollutant (POP) previously used as a timber treatment chemical to prevent sap stain and wood rot. Commonly used in wood treatment industries for the last 50 years, there are now many sites worldwide that are contaminated with PCP. Although persistent, PCP is a mobile contaminant and therefore has a propensity to leach and contaminate surrounding environments. Both willow (Salix sp., 'Tangoio') and poplar (Populus sp. 'Kawa') growing in an open-ended plastic greenhouse were found to tolerate soil PCP concentrations of 250 mg kg(-1) or less and both species stimulated a significant increase in soil microbial activity when compared to unplanted controls. Both poplar and willow could not survive PCP concentrations above 250 mg kg(-1) in soil. Pentachlorophenol degradation occurred in both planted and unplanted pots, but a higher rate of degradation was observed in the planted pots. Soil contaminated by wood-treatment activities often contains co-contaminants such as B, Cr, Cu and As, that are also used as timber preservatives. An additional column leaching experiment, done along side the potted trial, found that PCP, B, Cr, Cu and As were all present in the column leachate. This indicates that although Cu, Cr and As are generally considered immobile in the soil, they were mobilised under our column conditions. If a contaminated site were to be hydraulically 'sealed' using plants, a reticulation irrigation system should be installed to capture any contaminant leachate resulting from heavy rains. This captured leachate can either be independently treated, or reapplied to the site. Our data demonstrate a reduction in soil hydraulic conductivity with repeated application of leachate containing PCP and metal compounds but the soil did not become anaerobic. This would need to be considered in site remediation design.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16202508?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gryta, Hervé</style></author><author><style face="normal" font="default" size="100%">Carriconde, Fabian</style></author><author><style face="normal" font="default" size="100%">Charcosset, Jean-Yves</style></author><author><style face="normal" font="default" size="100%">Jargeat, Patricia</style></author><author><style face="normal" font="default" size="100%">Gardes, Monique</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Population dynamics of the ectomycorrhizal fungal species Tricholoma populinum and Tricholoma scalpturatum associated with black poplar under differing environmental conditions.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental microbiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Microbiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">8</style></volume><pages><style face="normal" font="default" size="100%">773-86</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Fungi combine sexual reproduction and clonal propagation. The balance between these two reproductive modes affects establishment dynamics, and ultimately the evolutionary potential of populations. The pattern of colonization was studied in two species of ectomycorrhizal fungi: Tricholoma populinum and Tricholoma scalpturatum. The former is considered to be a host specialist whereas T. scalpturatum is a generalist taxon. Fruit bodies of both basidiomycete species were mapped and collected over several years from a black poplar (Populus nigra) stand, at two different sites. Multilocus genotypes (= genets) were identified based on the analysis of random amplified polymorphic DNA (RAPD) patterns, inter-simple sequence repeat (ISSR) patterns and restriction fragment length polymorphisms (RFLPs) in the ribosomal DNA intergenic spacer (rDNA IGS). The genetic analyses revealed differences in local population dynamics between the two species. Tricholoma scalpturatum tended to capture new space through sexual spores whereas T. populinum did this by clonal growth, suggesting trade-offs in allocation of resources at the genet level. Genet numbers and sizes strongly differ between the two study sites, perhaps as a result of abiotic disturbance on mycelial establishment and genet behaviour.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16623736?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kim, Bong Gyu</style></author><author><style face="normal" font="default" size="100%">Lee, Youngshim</style></author><author><style face="normal" font="default" size="100%">Hur, Hor-Gil</style></author><author><style face="normal" font="default" size="100%">Lim, Yoongho</style></author><author><style face="normal" font="default" size="100%">Ahn, Joong-Hoon</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Production of three O-methhylated esculetins with Escherichia coli expressing O-methyltransferase from poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioscience, biotechnology, and biochemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biosci. Biotechnol. Biochem.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">70</style></volume><pages><style face="normal" font="default" size="100%">1269-72</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">O-Methyltransferase, POMT-9 was expressed in Escherichia coli. HPLC analysis of reaction products revealed three peaks corresponding to isoscopoletin, scopoletin, and scoparone, and their structures were determined using NMR. Biotransformation of esculetin with E. coli expressing POMT-9 generated scopoletin, isoscopoletin, and scoparone at 30.3, 21, and 31 microM respectively. POMT-9 is the first O-methyltransferase that produces three different O-methylated products.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16717435?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wan, Xianchong</style></author><author><style face="normal" font="default" size="100%">Landhäusser, Simon M</style></author><author><style face="normal" font="default" size="100%">Lieffers, Victor J</style></author><author><style face="normal" font="default" size="100%">Zwiazek, Janusz J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Signals controlling root suckering and adventitious shoot formation in aspen (Populus tremuloides).</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 May</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">26</style></volume><pages><style face="normal" font="default" size="100%">681-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We determined the effects of removal of leaves, stem axillary buds, or the entire shoot on root suckering (adventitious shoot formation by roots) and basal stem sprouts in 3- and 4-year-old potted seedlings of aspen (Populus tremuloides Michx.). The greatest number of root suckers (67.9 +/- 8.5 per plant) emerged after excision of the entire shoot. Defoliated and debudded stems were the major source of inhibitory agents for root suckering, although axillary buds and developing new leaves also exerted a significant inhibitory effect. Removal of mature leaves had only a minor effect on root suckering. Removal of a continuous band of bark (girdling) at the base of the stem consistently stimulated growth of adventitious shoots from the stem below the girdle and occasionally promoted root suckering. Exogenous application of indole-3-acetic acid to excised stumps inhibited root suckering and basal stem sprouting. Naphthylphthalamic acid (NPA), an auxin polar transport inhibitor, had no effect on root suckering or stem sprouting when it was applied to the bark of the basal stem. However, NPA significantly increased root suckering when it was applied to the exposed surface of xylem after girdling. These results suggest that polar transport of auxin in the xylem parenchyma is an important inhibitor of root suckering. On decapitated stems, vacuum extraction of xylem sap from the root system lowered the frequency of root suckering compared with decapitation alone, indicating that substance(s) originating in the root system also play a significant role in controlling root suckering.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16452082?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rouhier, Nicholas</style></author><author><style face="normal" font="default" size="100%">Gama, Filipe</style></author><author><style face="normal" font="default" size="100%">Wingsle, Gunnar</style></author><author><style face="normal" font="default" size="100%">Gelhaye, Eric</style></author><author><style face="normal" font="default" size="100%">Gans, Pierre</style></author><author><style face="normal" font="default" size="100%">Jacquot, Jean-Pierre</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Engineering functional artificial hybrid proteins between poplar peroxiredoxin II and glutaredoxin or thioredoxin.</style></title><secondary-title><style face="normal" font="default" size="100%">Biochemical and biophysical research communications</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biochem. Biophys. Res. Commun.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Mar 24</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">341</style></volume><pages><style face="normal" font="default" size="100%">1300-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The existence of natural peroxiredoxin-glutaredoxin hybrid enzymes in several bacteria is in line with previous findings indicating that poplar peroxiredoxin II can use glutaredoxin as an electron donor. This peroxiredoxin remains however unique since it also uses thioredoxin with a quite good efficiency. Based on the existing fusions, we have created artificial enzymes containing a poplar peroxiredoxin module linked to glutaredoxin or thioredoxin modules. The recombinant fusion enzymes folded properly into non-covalently bound homodimers or homotetramers. Two of the three protein constructs exhibit peroxidase activity, a reaction where the two modules need to function together, but they also display enzymatic activities specific of each module. In addition, mass spectrometry analyses indicate that the Prx module can be both glutathiolated or overoxidized in vitro. This is discussed in the light of the Prx reactivity.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16476584?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Klimmek, Frank</style></author><author><style face="normal" font="default" size="100%">Sjödin, Andreas</style></author><author><style face="normal" font="default" size="100%">Noutsos, Christos</style></author><author><style face="normal" font="default" size="100%">Leister, Dario</style></author><author><style face="normal" font="default" size="100%">Jansson, Stefan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Abundantly and rarely expressed Lhc protein genes exhibit distinct regulation patterns in plants.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">140</style></volume><pages><style face="normal" font="default" size="100%">793-804</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We have analyzed gene regulation of the Lhc supergene family in poplar (Populus spp.) and Arabidopsis (Arabidopsis thaliana) using digital expression profiling. Multivariate analysis of the tissue-specific, environmental, and developmental Lhc expression patterns in Arabidopsis and poplar was employed to characterize four rarely expressed Lhc genes, Lhca5, Lhca6, Lhcb7, and Lhcb4.3. Those genes have high expression levels under different conditions and in different tissues than the abundantly expressed Lhca1 to 4 and Lhcb1 to 6 genes that code for the 10 major types of higher plant light-harvesting proteins. However, in some of the datasets analyzed, the Lhcb4 and Lhcb6 genes as well as an Arabidopsis gene not present in poplar (Lhcb2.3) exhibited minor differences to the main cooperative Lhc gene expression pattern. The pattern of the rarely expressed Lhc genes was always found to be more similar to that of PsbS and the various light-harvesting-like genes, which might indicate distinct physiological functions for the rarely and abundantly expressed Lhc proteins. The previously undetected Lhcb7 gene encodes a novel plant Lhcb-type protein that possibly contains an additional, fourth, transmembrane N-terminal helix with a highly conserved motif. As the Lhcb4.3 gene seems to be present only in Eurosid species and as its regulation pattern varies significantly from that of Lhcb4.1 and Lhcb4.2, we conclude it to encode a distinct Lhc protein type, Lhcb8.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16524980?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ingvarsson, Pär K</style></author><author><style face="normal" font="default" size="100%">García, M Victoria</style></author><author><style face="normal" font="default" size="100%">Hall, David</style></author><author><style face="normal" font="default" size="100%">Luquez, Virginia</style></author><author><style face="normal" font="default" size="100%">Jansson, Stefan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Clinal variation in phyB2, a candidate gene for day-length-induced growth cessation and bud set, across a latitudinal gradient in European aspen (Populus tremula).</style></title><secondary-title><style face="normal" font="default" size="100%">Genetics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Genetics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">172</style></volume><pages><style face="normal" font="default" size="100%">1845-53</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The initiation of growth cessation and dormancy represents a critical ecological and evolutionary trade-off between survival and growth in most forest trees. The most important environmental cue regulating the initiation of dormancy is a shortening of the photoperiod and phytochrome genes have been implicated in short-day-induced bud set and growth cessation in Populus. We characterized patterns of DNA sequence variation at the putative candidate gene phyB2 in 4 populations of European aspen (Populus tremula) and scored single-nucleotide polymorphisms in an additional 12 populations collected along a latitudinal gradient in Sweden. We also measured bud set from a subset of these trees in a growth chamber experiment. Buds set showed significant clinal variation with latitude, explaining approximately 90% of the population variation in bud set. A sliding-window scan of phyB2 identified six putative regions with enhanced population differentiation and four SNPs showed significant clinal variation. The clinal variation at individual SNPs is suggestive of an adaptive response in phyB2 to local photoperiodic conditions. Three of four SNPs showing clinal variation were located in regions with excessive genetic differentiation, demonstrating that searching for regions of high genetic differentiation can be useful for identifying sites putatively involved in local adaptation.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16361240?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Geisler-Lee, Jane</style></author><author><style face="normal" font="default" size="100%">Geisler, Matt</style></author><author><style face="normal" font="default" size="100%">Coutinho, Pedro M</style></author><author><style face="normal" font="default" size="100%">Segerman, Bo</style></author><author><style face="normal" font="default" size="100%">Nishikubo, Nobuyuki</style></author><author><style face="normal" font="default" size="100%">Takahashi, Junko</style></author><author><style face="normal" font="default" size="100%">Aspeborg, Henrik</style></author><author><style face="normal" font="default" size="100%">Djerbi, Soraya</style></author><author><style face="normal" font="default" size="100%">Master, Emma</style></author><author><style face="normal" font="default" size="100%">Andersson-Gunnerås, Sara</style></author><author><style face="normal" font="default" size="100%">Sundberg, Björn</style></author><author><style face="normal" font="default" size="100%">Karpinski, Stanislaw</style></author><author><style face="normal" font="default" size="100%">Teeri, Tuula T</style></author><author><style face="normal" font="default" size="100%">Kleczkowski, Leszek A</style></author><author><style face="normal" font="default" size="100%">Henrissat, Bernard</style></author><author><style face="normal" font="default" size="100%">Mellerowicz, Ewa J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Poplar carbohydrate-active enzymes. Gene identification and expression analyses.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">140</style></volume><pages><style face="normal" font="default" size="100%">946-62</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Over 1,600 genes encoding carbohydrate-active enzymes (CAZymes) in the Populus trichocarpa (Torr. &amp; Gray) genome were identified based on sequence homology, annotated, and grouped into families of glycosyltransferases, glycoside hydrolases, carbohydrate esterases, polysaccharide lyases, and expansins. Poplar (Populus spp.) had approximately 1.6 times more CAZyme genes than Arabidopsis (Arabidopsis thaliana). Whereas most families were proportionally increased, xylan and pectin-related families were underrepresented and the GT1 family of secondary metabolite-glycosylating enzymes was overrepresented in poplar. CAZyme gene expression in poplar was analyzed using a collection of 100,000 expressed sequence tags from 17 different tissues and compared to microarray data for poplar and Arabidopsis. Expression of genes involved in pectin and hemicellulose metabolism was detected in all tissues, indicating a constant maintenance of transcripts encoding enzymes remodeling the cell wall matrix. The most abundant transcripts encoded sucrose synthases that were specifically expressed in wood-forming tissues along with cellulose synthase and homologs of KORRIGAN and ELP1. Woody tissues were the richest source of various other CAZyme transcripts, demonstrating the importance of this group of enzymes for xylogenesis. In contrast, there was little expression of genes related to starch metabolism during wood formation, consistent with the preferential flux of carbon to cell wall biosynthesis. Seasonally dormant meristems of poplar showed a high prevalence of transcripts related to starch metabolism and surprisingly retained transcripts of some cell wall synthesis enzymes. The data showed profound changes in CAZyme transcriptomes in different poplar tissues and pointed to some key differences in CAZyme genes and their regulation between herbaceous and woody plants.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16415215?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Langhans, Simone D</style></author><author><style face="normal" font="default" size="100%">Tockner, Klement</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The role of timing, duration, and frequency of inundation in controlling leaf litter decomposition in a river-floodplain ecosystem (Tagliamento, northeastern Italy).</style></title><secondary-title><style face="normal" font="default" size="100%">Oecologia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Oecologia</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Mar</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">147</style></volume><pages><style face="normal" font="default" size="100%">501-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Despite growing recognition of the importance of a natural flow regime in river-floodplain systems, researchers struggle to quantify ecosystem responses to altered hydrological regimes. How do frequency, timing, and duration of inundation affect fundamental ecosystem processes such as leaf litter decomposition? Along the semi-natural Tagliamento River corridor, located in northeastern Italy, we employed in situ experiments to separate effects of different inundation components on breakdown rates of black poplar (Populus nigra). We used a litter-bag method with two different mesh sizes to investigate how fungi and macroinvertebrates influence leaf breakdown rates. Ten treatments, each representing a specific combination of duration and frequency of inundation, were deployed in two seasons (summer, winter) to mimic complex inundation patterns. After 30 days of exposure, mean percentage of remaining leaf litter (ash free dry mass) ranged between 51% (permanent wet) and 88% (permanent dry). Leaf breakdown was significantly faster in winter than in summer. Duration of inundation was the main inundation component that controlled leaf breakdown rates. Leaf-shredding macroinvertebrates played only a role in the permanent wet treatment. Fungal parameters explained the faster leaf breakdown in winter. Our study suggests that modifications of the inundation regime will directly modify established decomposition processes. Factors reducing duration of inundation will decelerate leaf breakdown rates, whereas a decrease in flow variation will reduce leaf breakdown heterogeneity.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16237537?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Brown, John J</style></author><author><style face="normal" font="default" size="100%">Kittelson, Neal T</style></author><author><style face="normal" font="default" size="100%">Hannon, Eugene R</style></author><author><style face="normal" font="default" size="100%">Walsh, Douglas B</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">An endemic population of western poplar clearwing moths (Lepidoptera: Sesiidae) invades a monoculture of hybrid poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of economic entomology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Econ. Entomol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">99</style></volume><pages><style face="normal" font="default" size="100%">771-9</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Western poplar clearwing, Paranthrene robiniae (Hy. Edwards) (Lepidoptera: Sesiidae), is endemic in Pacific Northwest riparian habitats at low population densities. These moths have colonized commercial hybrid poplar (Populus spp.) plantings. Moth populations increased rapidly and became a major pest. Trap catches of male moths in mid-season surveys increased 190-fold from 95 in 2001 to &gt;18,500 in 2002 across 6597 ha of poplars monitored. The outbreak of western poplar clearwings was widespread in 2002. Pheromone-baited traps placed one trap per 81.75 ha over 13,274 ha of commercial poplars captured &gt;108,000 male moths in 2002. Damage to commercial poplars included girdling of saplings and burrows in limbs and trunks of trees. Repeated applications of chlorpyrifos failed to reduce the abundance of moths in 2002. Two management strategies over two separate plantations of approximately 6500 ha each were contrasted. Future control strategies recommend a halt to the use of contact insecticides that target adult moths. Short-term (3-5 yr) control should involve a pheromone-based mating disruption strategy followed eventually by selection of a clone that is less susceptible to P. robiniae attack.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16813311?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Osier, Tod L</style></author><author><style face="normal" font="default" size="100%">Lindroth, Richard L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genotype and environment determine allocation to and costs of resistance in quaking aspen.</style></title><secondary-title><style face="normal" font="default" size="100%">Oecologia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Oecologia</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">148</style></volume><pages><style face="normal" font="default" size="100%">293-303</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Although genetic variability and resource availability both influence plant chemical composition, little is known about how these factors interact to modulate costs of resistance, expressed as negative correlations between growth and defense. We evaluated genotype x environment effects on foliar chemistry and growth of quaking aspen (Populus tremuloides) by growing multiple aspen genotypes under variable conditions of light and soil nutrient availability in a common garden. Foliage was analyzed for levels of nitrogen, phenolic glycosides and condensed tannins. Bioassays of leaf quality were conducted with fourth-stadium gypsy moth (Lymantria dispar) larvae. Results revealed strong effects of plant genotype, light availability and nutrient availability; the importance of each factor depended upon compound type. For example, tannin concentrations differed little among genotypes and across nutrient regimes under low light conditions, but markedly so under high light conditions. Phenolic glycoside concentrations, in contrast, were largely determined by genotype. Variation in phenolic glycoside concentrations among genotypes was the most important factor affecting gypsy moth performance. Gypsy moth biomass and development time were negatively and positively correlated, respectively, with phenolic glycoside levels. Allocation to phenolic glycosides appeared to be costly in terms of growth, but only under resource-limiting conditions. Context-dependent trade-offs help to explain why costs of allocation to resistance are often difficult to demonstrate.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16468055?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Giachetti, Giorgio</style></author><author><style face="normal" font="default" size="100%">Sebastiani, Luca</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Metal accumulation in poplar plant grown with industrial wastes.</style></title><secondary-title><style face="normal" font="default" size="100%">Chemosphere</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Chemosphere</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">64</style></volume><pages><style face="normal" font="default" size="100%">446-54</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In this study the effects of different levels of industrial wastes on growth traits and metal accumulation in aerial portions were determined for Populusxeuramericana clone I-214. The experiment started in April 2003. Scions of Populusxeuramericana clone I-214, were grown outdoor near Pisa (Italy), in lisimeters filled with soil naturally present in the land around the experimental site, were daily drip irrigated, hand weeded, monthly fertilized, pruned for a unique shoot and cultivated with four increasing treatments: soil non-amended, soil amended with 4.8 kgm(-2), with 9.6 kgm(-2) and with 19.2 kgm(-2) of fresh tannery waste. The climatic parameters were daily recorded throughout the whole experiment. Growth relieves were performed during the growing season. After six months since the plantation of the scions, aerial portions of every plant were harvested for biomass and metal content analyses. Data demonstrated that the waste exerted beneficial effects on poplars mainly through a general increase of growth traits and that the nutrients relocation is the mechanisms involved in modulating growth rate. The concentration and the amount of the mineral elements analysed (N, P, K, Na, Ca, Mg, S, B, Fe, Mn, Cu, Zn, Cr) changed determinately among treatments, organs and position. We concluded that phytoremediation strategies of tannery wastes might be possible and sustainable for polar plantations in soil amended with non-hazardous levels of industrial waste, which maintain total heavy metals concentration close to background values.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16403550?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">De Bodt, Stefanie</style></author><author><style face="normal" font="default" size="100%">Theissen, Guenter</style></author><author><style face="normal" font="default" size="100%">Van de Peer, Yves</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Promoter analysis of MADS-box genes in eudicots through phylogenetic footprinting.</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular biology and evolution</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Biol. Evol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">23</style></volume><pages><style face="normal" font="default" size="100%">1293-303</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The MIKC MADS-box gene family has been shaped by extensive gene duplications giving rise to subfamilies of genes with distinct functions and expression patterns. However, within these subfamilies the functional assignment is not that clear-cut, and considerable functional redundancy exists. One way to investigate the diversity in regulation present in these subfamilies is promoter sequence analysis. With the advent of genome sequencing projects, we are now able to exert a comparative analysis of Arabidopsis and poplar promoters of MADS-box genes belonging to the same subfamily. Based on the principle of phylogenetic footprinting, sequences conserved between the promoters of homologous genes are thought to be functional. Here, we have investigated the evolution of MADS-box genes at the promoter level and show that many genes have diverged in their regulatory sequences after duplication and/or speciation. Furthermore, using phylogenetic footprinting, a distinction can be made between redundancy, neo/nonfunctionalization, and subfunctionalization.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16581940?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Pregitzer, Kurt</style></author><author><style face="normal" font="default" size="100%">Loya, Wendy</style></author><author><style face="normal" font="default" size="100%">Kubiske, Mark</style></author><author><style face="normal" font="default" size="100%">Zak, Donald</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Soil respiration in northern forests exposed to elevated atmospheric carbon dioxide and ozone.</style></title><secondary-title><style face="normal" font="default" size="100%">Oecologia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Oecologia</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">148</style></volume><pages><style face="normal" font="default" size="100%">503-16</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The aspen free-air CO2 and O3 enrichment (FACTS II-FACE) study in Rhinelander, Wisconsin, USA, is designed to understand the mechanisms by which young northern deciduous forest ecosystems respond to elevated atmospheric carbon dioxide (CO2) and elevated tropospheric ozone (O3) in a replicated, factorial, field experiment. Soil respiration is the second largest flux of carbon (C) in these ecosystems, and the objective of this study was to understand how soil respiration responded to the experimental treatments as these fast-growing stands of pure aspen and birch + aspen approached maximum leaf area. Rates of soil respiration were typically lowest in the elevated O3 treatment. Elevated CO2 significantly stimulated soil respiration (8-26%) compared to the control treatment in both community types over all three growing seasons. In years 6-7 of the experiment, the greatest rates of soil respiration occurred in the interaction treatment (CO2 + O3), and rates of soil respiration were 15-25% greater in this treatment than in the elevated CO2 treatment, depending on year and community type. Two of the treatments, elevated CO2 and elevated CO2 + O3, were fumigated with 13C-depleted CO2, and in these two treatments we used standard isotope mixing models to understand the proportions of new and old C in soil respiration. During the peak of the growing season, C fixed since the initiation of the experiment in 1998 (new C) accounted for 60-80% of total soil respiration. The isotope measurements independently confirmed that more new C was respired from the interaction treatment compared to the elevated CO2 treatment. A period of low soil moisture late in the 2003 growing season resulted in soil respiration with an isotopic signature 4-6 per thousand enriched in 13C compared to sample dates when the percentage soil moisture was higher. In 2004, an extended period of low soil moisture during August and early September, punctuated by a significant rainfall event, resulted in soil respiration that was temporarily 4-6 per thousand more depleted in 13C. Up to 50% of the Earth's forests will see elevated concentrations of both CO2 and O3 in the coming decades and these interacting atmospheric trace gases stimulated soil respiration in this study.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16489459?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">French, Christopher J</style></author><author><style face="normal" font="default" size="100%">Dickinson, Nicholas M</style></author><author><style face="normal" font="default" size="100%">Putwain, Philip D</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Woody biomass phytoremediation of contaminated brownfield land.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental pollution (Barking, Essex : 1987)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Pollut.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">141</style></volume><pages><style face="normal" font="default" size="100%">387-95</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Economic and environmental regeneration of post-industrial landscapes frequently involves some element of re-afforestation or tree planting. We report field trials that evaluate whether woody biomass production is compatible with managing residual trace element contamination in brownfield soils. Large-scale mapping of contamination showed a heterogenous dispersion of metals and arsenic, and highly localised within-site hotspots. Yields of Salix, Populus and Alnus were economically viable, showing that short-rotation coppice has a potentially valuable role in community forestry. Mass balance modelling demonstrated that phytoextraction potentially could reduce contamination hotspots of more mobile elements (Cd and Zn) within a 25-30-year life cycle of the crops. Cd and Zn in stems and foliage of Salix were 4-13 times higher than EDTA-extractable soil concentrations. Lability of other trace elements (As, Pb, Cu, Ni) was not increased 3 years after planting the coppice; woody biomass may provide an effective reduction of exposure (phyto-stabilization) to these less mobile contaminants.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16271426?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Qin, Juan</style></author><author><style face="normal" font="default" size="100%">Shangguan, Zhouping</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Physiological-ecological effects of Populus davidiana--Quercus liaotungensis mixed forest in Ziwuling forest area].</style></title><secondary-title><style face="normal" font="default" size="100%">Ying yong sheng tai xue bao = The journal of applied ecology / Zhongguo sheng tai xue xue hui, Zhongguo ke xue yuan Shenyang ying yong sheng tai yan jiu suo zhu ban</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ying Yong Sheng Tai Xue Bao</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jun</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">17</style></volume><pages><style face="normal" font="default" size="100%">972-6</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">This paper studied the soil physical- properties under Populus davidiana, Quercus liaotungensis, and Populus davidiana--Quercus liaotungensis mixed forest in the Ziwuling forest area of Loess Plateau, and the leaf photosysthetic characteristics of these three types of forests. The results showed that soil moisture content in 0 - 300 cm layer was the highest under P. davidiana forest, and obviously increased below 200 cm in depth under P. davidiana--Q. liaotungensis mixed forest, which was 10.5% - 19.76% higher than that under Q. liaotungensis forest. In 0 - 60 cm layer, P. davidiana forest showed the highest soil bulk density and the lowest soil porosity, while P. davidiana--Q. liaotungensis mixed forest presented the lowest soil bulk density and the highest soil porosity, and both of these indices surpassed their corresponding values under pure forests, which indicated that the mixed forest could make effective use of water in deep soil, and obviously improved soil physical and chemical properties. P. davidiana and Q. liaotungensis had a higher content of leaf chlorophyll than P. davidiana--Q. liaotungensis mixed forest, and Q. liaotungensis presented the highest leaf chlorophyll content. Q. liaotungensis had the highest photosynthetic rate and stomatal conductance, followed by P. davidiana, and by P. davidiana--Q. liaotungensis mixed forest. The water use efficiency of the forests ranked in the decreasing order of Q. liaotungensis in pure forest, Q. liaotungensis in mixed forest, P. davidiana in mixed forest, and P. davidiana in pure forest. Q. liaotungensis in mixed forest presented the highest F(v)/F(m) and F(v)/F(o), and did not remarkably differ from those in pure forest, but in the mixed forest, the F(v)/F(m) and F(v)/F(o) of P. davidiana were markedly lower than those of P. davidiana in pure forest. Both the q(p) and NPQ of P. davidiana and Q. liaotungensis in pure forests were higher than those in mixed forest, respectively. In Ziwuling forest area, Q. liaotungensis in Q. liaotungensis--dominant climax community tended to be more stable, and grew better than Q. liaotungensis in P. davidiana--Q. liaotungensis mixed forest, and P. davidiana would be gradually replaced. Compared with P. davidiana in pure forest, P. davidiana in its mixed forest was at a disadvantage in its growth.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16964925?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Feng, Yingang</style></author><author><style face="normal" font="default" size="100%">Zhong, Nan</style></author><author><style face="normal" font="default" size="100%">Rouhier, Nicolas</style></author><author><style face="normal" font="default" size="100%">Hase, Toshiharu</style></author><author><style face="normal" font="default" size="100%">Kusunoki, Masami</style></author><author><style face="normal" font="default" size="100%">Jacquot, Jean-Pierre</style></author><author><style face="normal" font="default" size="100%">Jin, Changwen</style></author><author><style face="normal" font="default" size="100%">Xia, Bin</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Structural insight into poplar glutaredoxin C1 with a bridging iron-sulfur cluster at the active site.</style></title><secondary-title><style face="normal" font="default" size="100%">Biochemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biochemistry</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jul 4</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">45</style></volume><pages><style face="normal" font="default" size="100%">7998-8008</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Glutaredoxins are glutathione-dependent enzymes that function to reduce disulfide bonds in vivo. Interestingly, a recent discovery indicates that some glutaredoxins can also exist in another form, an iron-sulfur protein [Lillig, C. H., et al. (2005) Proc. Natl. Acad. Sci. U.S.A. 102, 8168-8173]. This provides a direct connection between glutaredoxins and iron-sulfur proteins, suggesting a possible new regulatory role of iron-sulfur clusters along with the new functional switch of glutaredoxins. Biochemical studies have indicated that poplar glutaredoxin C1 (Grx-C1) is also such a biform protein. The apo form (monomer) of Grx-C1 is a regular glutaredoxin, and the holo form (dimer) is an iron-sulfur protein with a bridging [2Fe-2S] cluster. Here, we report the structural characterizations of poplar Grx-C1 in both the apo and holo forms by NMR spectroscopy. The solution structure of the reduced apo Grx-C1, which is the first plant Grx structure, shows a typical Grx fold. When poplar Grx-C1 forms a dimer with an iron-sulfur cluster, each subunit of the holo form still retains the overall fold of the apo form. The bridging iron-sulfur cluster in holo Grx-C1 is coordinated near the active site. In addition to the iron-sulfur cluster linker, helix alpha3 of each subunit is probably involved in the direct contact between the two subunits. Moreover, two glutathione molecules are identified in the vicinity of the iron-sulfur cluster and very likely participate in cluster coordination. Taken together, we propose that the bridging [2Fe-2S] cluster is coordinated by the first cysteine at the glutaredoxin active site from each subunit of holo Grx-C1, along with two cysteines from two glutathione molecules. Our studies reveal that holo Grx-C1 has a novel structural and iron-sulfur cluster coordination pattern for an iron-sulfur protein.</style></abstract><issue><style face="normal" font="default" size="100%">26</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16800625?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Filichkin, S A</style></author><author><style face="normal" font="default" size="100%">Meilan, R</style></author><author><style face="normal" font="default" size="100%">Busov, V B</style></author><author><style face="normal" font="default" size="100%">Ma, C</style></author><author><style face="normal" font="default" size="100%">Brunner, A M</style></author><author><style face="normal" font="default" size="100%">Strauss, S H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Alcohol-inducible gene expression in transgenic Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant cell reports</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Rep.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">25</style></volume><pages><style face="normal" font="default" size="100%">660-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We tested the efficiency and optimized the conditions for controlled alcohol-inducible transgene expression in Populus using gus as a reporter gene. Specificity of induction, efficiency in different organs, effect of three chemical inducers, and induction methods were tested using up to 10 independent transgenic events generated in two different Populus genotypes. The optimal inducer concentration and the duration of induction period were determined in dose-response and in time-course experiments. Under in vitro conditions, beta-glucuronidase (GUS) induction was efficient both in the aerial parts and in the roots of regenerated plantlets. Among the chemical inducers tested, ethanol was the most effective activator with no apparent phytotoxicity when concentrations were at or below 2%. After 5 days of treatment, fluorometrically-determined the GUS activity could be detected when inducing with ethanol at concentrations as low as 0.5%. Prolonged induction by ethanol vapors significantly increased the GUS activity in leaves from both the tissue culture plants and greenhouse-grown plants.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16496153?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Davey, P A</style></author><author><style face="normal" font="default" size="100%">Olcer, H</style></author><author><style face="normal" font="default" size="100%">Zakhleniuk, O</style></author><author><style face="normal" font="default" size="100%">Bernacchi, C J</style></author><author><style face="normal" font="default" size="100%">Calfapietra, C</style></author><author><style face="normal" font="default" size="100%">Long, S P</style></author><author><style face="normal" font="default" size="100%">Raines, C A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Can fast-growing plantation trees escape biochemical down-regulation of photosynthesis when grown throughout their complete production cycle in the open air under elevated carbon dioxide?</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">1235-44</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Poplar trees sustain close to the predicted increase in leaf photosynthesis when grown under long-term elevated CO2 concentration ([CO2]). To investigate the mechanisms underlying this response, carbohydrate accumulation and protein expression were determined over four seasons of growth. No increase in the levels of soluble carbohydrates was observed in the young expanding or mature sun leaves of the three poplar genotypes during this period. However, substantial increases in starch levels were observed in the mature leaves of all three poplar genotypes grown in elevated [CO2]. Despite the very high starch levels, no changes in the expression of photosynthetic Calvin cycle proteins, or in the starch biosynthetic enzyme ADP-glucose pyrophosphorylase (AGPase), were observed. This suggested that no long-term photosynthetic acclimation to CO2 occurred in these plants. Our data indicate that poplar trees are able to 'escape' from long-term, acclimatory down-regulation of photosynthesis through a high capacity for starch synthesis and carbon export. These findings show that these poplar genotypes are well suited to the elevated [CO2] conditions forecast for the middle of this century and may be particularly suited for planting for the long-term carbon sequestration into wood.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17080946?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Benedict, Catherine</style></author><author><style face="normal" font="default" size="100%">Skinner, Jeffrey S</style></author><author><style face="normal" font="default" size="100%">Meng, Rengong</style></author><author><style face="normal" font="default" size="100%">Chang, Yongjian</style></author><author><style face="normal" font="default" size="100%">Bhalerao, Rishikesh</style></author><author><style face="normal" font="default" size="100%">Huner, Norman P A</style></author><author><style face="normal" font="default" size="100%">Finn, Chad E</style></author><author><style face="normal" font="default" size="100%">Chen, Tony H H</style></author><author><style face="normal" font="default" size="100%">Hurry, Vaughan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The CBF1-dependent low temperature signalling pathway, regulon and increase in freeze tolerance are conserved in Populus spp.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">1259-72</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The meristematic tissues of temperate woody perennials must acclimate to freezing temperatures to survive the winter and resume growth the following year. To determine whether the C-repeat binding factor (CBF) family of transcription factors contributing to this process in annual herbaceous species also functions in woody perennials, we investigated the changes in phenotype and transcript profile of transgenic Populus constitutively expressing CBF1 from Arabidopsis (AtCBF1). Ectopic expression of AtCBF1 was sufficient to significantly increase the freezing tolerance of non-acclimated leaves and stems relative to wild-type plants. cDNA microarray experiments identified genes up-regulated by ectopic AtCBF1 expression in Populus, demonstrated a strong conservation of the CBF regulon between Populus and Arabidopsis and identified differences between leaf and stem regulons. We studied the induction kinetics and tissue specificity of four CBF paralogues identified from the Populus balsamifera subsp. trichocarpa genome sequence (PtCBFs). All four PtCBFs are cold-inducible in leaves, but only PtCBF1 and PtCBF3 show significant induction in stems. Our results suggest that the central role played by the CBF family of transcriptional activators in cold acclimation of Arabidopsis has been maintained in Populus. However, the differential expression of the PtCBFs and differing clusters of CBF-responsive genes in annual (leaf) and perennial (stem) tissues suggest that the perennial-driven evolution of winter dormancy may have given rise to specific roles for these 'master-switches' in the different annual and perennial tissues of woody species.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17080948?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lu, Shanfa</style></author><author><style face="normal" font="default" size="100%">Zhou, Yihua</style></author><author><style face="normal" font="default" size="100%">Li, Laigeng</style></author><author><style face="normal" font="default" size="100%">Chiang, Vincent L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Distinct roles of cinnamate 4-hydroxylase genes in Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant &amp; cell physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">47</style></volume><pages><style face="normal" font="default" size="100%">905-14</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Cinnamate 4-hydroxylase (C4H) catalyzes the conversion of cinnamate into 4-hydroxy-cinnamate, a key reaction of the phenylpropanoid pathway which leads to the biosynthesis of several secondary metabolites. C4H genes exist as a multigene family in various plant species. In order to understand the roles of individual C4H members, four C4H cDNAs (PtreC4H) were isolated from Populus tremuloides and three C4H loci (PtriC4H) were identified in the P. trichocarpa genome. The ability of Populus C4H isoforms to convert trans-cinnamate into p-coumaric acid was verified by the examination of yeast recombinant PtreC4H proteins. Populus C4H genes were expressed in various tissues, including developing xylem, phloem and epidermis; however, the expression patterns of individual members were different from each other. Sequential analysis of C4H promoters showed that the differential expression of C4H genes was associated with cis-acting regulatory elements such as box L, box P and H box, suggesting that the divergent C4H isoforms played distinct roles in the production of secondary metabolites. The involvement of specific C4H isoforms in the biosynthesis of guaiacyl and syringyl monolignols is discussed.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16720648?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Dluzniewska, Paulina</style></author><author><style face="normal" font="default" size="100%">Gessler, Arthur</style></author><author><style face="normal" font="default" size="100%">Kopriva, Stanislav</style></author><author><style face="normal" font="default" size="100%">Strnad, Miroslav</style></author><author><style face="normal" font="default" size="100%">Novák, Ondrej</style></author><author><style face="normal" font="default" size="100%">Dietrich, Henriette</style></author><author><style face="normal" font="default" size="100%">Rennenberg, Heinz</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Exogenous supply of glutamine and active cytokinin to the roots reduces NO3- uptake rates in poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">1284-97</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The present study shows for the first time the influence of exogenously applied amino acids and cytokinin on the physiological and molecular aspects of N metabolism in poplar trees. In a short-term feeding experiment, glutamine or trans-zeatin riboside (tZR) was added directly to the nutrient solution. NO3- net uptake declined significantly in response to both treatments. Feeding with glutamine brought about an increase in concentrations of different amino compounds in the roots (glutamine, glutamate, alanine, gamma-amino butyric acid (GABA) and NH4+, which negatively correlated with the net NO3- uptake. The plants showed a reduction of cytosolic glutamine synthetase 1 (GS1) transcript level in the roots. In addition, glutamine feeding changed the root-to-shoot distribution on N assimilation in favour of the leaves and plant internal N cycling. tZR treatment resulted in expansion of zeatin-type (Z-type) cytokinins in the roots and increased nitrate reductase (NR)-mRNA level. The results indicate that both particular amino acids and active cytokinins are involved in the feedback regulation of N uptake and metabolism in poplar. We propose that inhibition of N uptake by cytokinins in poplar is more complex than that mediated by amino compounds, and other effectors are involved in this regulation.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17080950?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Morreel, Kris</style></author><author><style face="normal" font="default" size="100%">Goeminne, Geert</style></author><author><style face="normal" font="default" size="100%">Storme, Véronique</style></author><author><style face="normal" font="default" size="100%">Sterck, Lieven</style></author><author><style face="normal" font="default" size="100%">Ralph, John</style></author><author><style face="normal" font="default" size="100%">Coppieters, Wouter</style></author><author><style face="normal" font="default" size="100%">Breyne, Peter</style></author><author><style face="normal" font="default" size="100%">Steenackers, Marijke</style></author><author><style face="normal" font="default" size="100%">Georges, Michel</style></author><author><style face="normal" font="default" size="100%">Messens, Eric</style></author><author><style face="normal" font="default" size="100%">Boerjan, Wout</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genetical metabolomics of flavonoid biosynthesis in Populus: a case study.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">47</style></volume><pages><style face="normal" font="default" size="100%">224-37</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Genetical metabolomics [metabolite profiling combined with quantitative trait locus (QTL) analysis] has been proposed as a new tool to identify loci that control metabolite abundances. This concept was evaluated in a case study with the model tree Populus. Using HPLC, the peak abundances were analyzed of 15 closely related flavonoids present in apical tissues of two full-sib poplar families, Populus deltoides cv. S9-2 x P. nigra cv. Ghoy and P. deltoides cv. S9-2 x P. trichocarpa cv. V24, and correlation and QTL analysis were used to detect flux control points in flavonoid biosynthesis. Four robust metabolite quantitative trait loci (mQTL), associated with rate-limiting steps in flavonoid biosynthesis, were mapped. Each mQTL was involved in the flux control to one or two flavonoids. Based on the identities of the affected metabolites and the flavonoid pathway structure, a tentative function was assigned to three of these mQTL, and the corresponding candidate genes were mapped. The data indicate that the combination of metabolite profiling with QTL analysis is a valuable tool to identify control points in a complex metabolic pathway of closely related compounds.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16774647?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Talyzina, Nina M</style></author><author><style face="normal" font="default" size="100%">Ingvarsson, Pär K</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Molecular evolution of a small gene family of wound inducible Kunitz trypsin inhibitors in Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of molecular evolution</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Mol. Evol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">63</style></volume><pages><style face="normal" font="default" size="100%">108-19</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Maximum likelihood models of codon substitutions were used to analyze the molecular evolution of a Kunitz trypsin inhibitor (KTI) gene family in Populus and Salix. The methods support previous assertions that the KTI genes comprise a rapidly evolving gene family. Models that allow for codon specific estimates of the ratio of nonsynonymous to synonymous substitutions (omega) among sites detect positive Darwinian selection at several sites in the KTI protein. In addition, branch-specific maximum likelihood models show that there is significant heterogeneity in omega among branches of the KTI phylogeny. In particular, omega is substantially higher following duplication than speciation. There is also evidence for significant rate heterogeneity following gene duplication, suggesting different evolutionary rates in newly arisen gene duplicates. The results indicate uneven evolutionary rates both between sites in the KTI protein and among different lineages in the KTI phylogeny, which is incompatible with a neutral model of sequence evolution.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16755353?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Eken, C</style></author><author><style face="normal" font="default" size="100%">Tozlu, G</style></author><author><style face="normal" font="default" size="100%">Dane, E</style></author><author><style face="normal" font="default" size="100%">Coruh, S</style></author><author><style face="normal" font="default" size="100%">Demirci, E</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Pathogenicity of Beauveria bassiana (Deuteromycotina: Hypomycetes) to larvae of the small poplar longhorn beetle, Saperda populnea (Coleoptera: Cerambycidae).</style></title><secondary-title><style face="normal" font="default" size="100%">Mycopathologia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mycopathologia</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">162</style></volume><pages><style face="normal" font="default" size="100%">69-71</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The small poplar longhorn beetle, Saperda populnea is an important pest of Lombardy poplars (Populus nigra L.) in Turkey. A survey for natural entomopathogenic fungi of S. populnea larvae was made in Erzurum, Turkey, during the period 2004-2005. Larvae (13.5%) infected with a strain of the fungus Beauveria bassiana were found. The pathogenicity of B. bassiana strain 46 was conducted with different concentrations of conidia (10(6), 10(7) and 10(8) conidia/ml) of this isolate on S. populnea larvae. The lowest concentration (10(6) conidia/ml) caused about 56% mortality within 6 days. One hundred percent mortality was achieved after median lethal time (LT(50)) of 4.6 and 4.4 days for 10(7) and 10(8) conidia/ml, respectively. There were no significant differences between median lethal times. This is the first record of natural infection of S. populnea larvae by B. bassiana.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16830195?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Marron, Nicolas</style></author><author><style face="normal" font="default" size="100%">Bastien, Catherine</style></author><author><style face="normal" font="default" size="100%">Sabatti, Maurizio</style></author><author><style face="normal" font="default" size="100%">Taylor, Gail</style></author><author><style face="normal" font="default" size="100%">Ceulemans, Reinhart</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Plasticity of growth and sylleptic branchiness in two poplar families grown at three sites across Europe.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">26</style></volume><pages><style face="normal" font="default" size="100%">935-46</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Two hybrid poplar maternal half-sib families, resulting from controlled crosses of the female parent Populus deltoides 'S9-2' with P. nigra 'Ghoy' and P. trichocarpa 'V24', were grown at three sites: northern Italy, central France and southern England. Juvenile stem growth traits (height, circumference and volume) and sylleptic branchiness (number of branches, density of branches per unit of stem height, percentage of the stem carrying branches and distance of the highest sylleptic branch to the top of the stem) were measured on 1-year-old shoots. Our general objectives were to determine the degree to which the expression of stem growth and syllepsis and the relationships between them are affected by environmental conditions and to evaluate the efficiency of indirect selection for stem growth using branching traits as secondary criteria. The performance of both families differed significantly within and between sites. Pronounced heterosis was observed and highly significant genotype x environment interactions were found for all traits across the sites. Syllepsis showed more marked genetic variation and plasticity than stem growth traits. Relationships between sylleptic branchiness and stem growth depended on environmental conditions. Heritability values at the individual level ranged between 0.09 and 0.59, but genetic gain in stem volume was not significantly improved when selection was based on sylleptic branch characteristics. However, despite strong phenotypic plasticity among sites, genotypic ranking among the sites was relatively stable.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16585039?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Vanden Wymelenberg, Amber</style></author><author><style face="normal" font="default" size="100%">Sabat, Grzegorz</style></author><author><style face="normal" font="default" size="100%">Mozuch, Michael</style></author><author><style face="normal" font="default" size="100%">Kersten, Philip J</style></author><author><style face="normal" font="default" size="100%">Cullen, Dan</style></author><author><style face="normal" font="default" size="100%">Blanchette, Robert A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Structure, organization, and transcriptional regulation of a family of copper radical oxidase genes in the lignin-degrading basidiomycete Phanerochaete chrysosporium.</style></title><secondary-title><style face="normal" font="default" size="100%">Applied and environmental microbiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Appl. Environ. Microbiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">72</style></volume><pages><style face="normal" font="default" size="100%">4871-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The white rot basidiomycete Phanerochaete chrysosporium produces an array of nonspecific extracellular enzymes thought to be involved in lignin degradation, including lignin peroxidases, manganese peroxidases, and the H2O2-generating copper radical oxidase, glyoxal oxidase (GLX). Preliminary analysis of the P. chrysosporium draft genome had identified six sequences with significant similarity to GLX and designated cro1 through cro6. The predicted mature protein sequences diverge substantially from one another, but the residues coordinating copper and constituting the radical redox site are conserved. Transcript profiles, microscopic examination, and lignin analysis of inoculated thin wood sections are consistent with differential regulation as decay advances. The cro2-encoded protein was detected by liquid chromatography-tandem mass spectrometry in defined medium. The cro2 cDNA was successfully expressed in Aspergillus nidulans under the control of the A. niger glucoamylase promoter and secretion signal. The recombinant CRO2 protein had a substantially different substrate preference than GLX. The role of structurally and functionally diverse cro genes in lignocellulose degradation remains to be established.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16820482?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Brenner, Richard E</style></author><author><style face="normal" font="default" size="100%">Boone, Richard D</style></author><author><style face="normal" font="default" size="100%">Jones, Jeremy B</style></author><author><style face="normal" font="default" size="100%">Lajtha, Kate</style></author><author><style face="normal" font="default" size="100%">Ruess, Roger W</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Successional and physical controls on the retention of nitrogen in an undisturbed boreal forest ecosystem.</style></title><secondary-title><style face="normal" font="default" size="100%">Oecologia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Oecologia</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">148</style></volume><pages><style face="normal" font="default" size="100%">602-11</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Floristic succession in the boreal forest can have a dramatic influence on ecosystem nutrient cycling. We predicted that a decrease in plant and microbial demand for nitrogen (N) during the transition from mid- to late-succession forests would induce an increase in the leaching of dissolved inorganic nitrogen (DIN), relative to dissolved organic nitrogen (DON). To test this, we examined the chemistry of the soil solution collected from within and below the main rooting zones of mid- and late-succession forests, located along the Tanana River in interior Alaska. We also used a combination of hydrological and chemical analyses to investigate a key assumption of our methodology: that patterns of soil water movement did not change during this transition. Between stands, there was no difference in the proportion of DIN below the rooting zone. 84-98% of DIN at both depths consisted of nitrate, which was significantly higher in the deeper mineral soil than at the soil surface (0.46+/-0.12 mg NO(-) (3) -N l(-1) vs 0.17+/-0.12 mg NO(-) (3) -N l(-1), respectively), and 79-92% of the total dissolved N consisted of DON. Contrary to our original assumption that nutrients were primarily leached downward, out of the rooting zone, we found much evidence to suggest that the glacially-fed Tanana River (&gt;200 m from these stands) was contributing to the influx of water and nutrients into the soil active layer of both stands. Soil water potentials were positively correlated with river discharge; and ionic and isotopic (delta(18)O of H(2)O) values of the soil solution closely matched those of river water. Thus, our ability to elucidate biological control over ecosystem N retention was confounded by riverine nutrient inputs. Climatic warming is likely to extend the season of glacial melt and increase riverine nutrient inputs to forests along glacially-fed rivers.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16521021?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Jonsson, Thorbergur H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Terminal bud failure of black cottonwood (Populus trichocarpa) exposed to salt-laden winter storms.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">26</style></volume><pages><style face="normal" font="default" size="100%">905-14</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">At coastal sites, trees are exposed to marine aerosols that may cause foliar necrosis and shoot dieback, which can result in deformed crowns and contorted stems. A six-year study of leaf primordia in terminal buds of black cottonwood trees (Populus trichocarpa Torr. &amp; Gray) on Heimaey Island off the south coast of Iceland was undertaken to elucidate the physiological events associated with salt-deposition-related bud failure. Leaf and bud lengths, dry mass, water content and chloride concentrations were monitored and related to four phenological stages: (1) bud set; (2) dormancy induction; (3) dormancy release; and (4) bud break. The trees set buds in July and shed their leaves by late September. Leaf primordia generally stopped growing by September 10 +/- 22 days and attained midwinter water content in late September. Leaf growth commenced in the terminal buds by March 2 +/- 16 days, but mean dates of bud swelling and bud break were April 29 +/- 19 and May 10 +/- 12 days. In summer and until November, chloride concentrations in leaf primordia were low, but increasing. Chloride concentrations remained stable from December to February, even though the dormant trees were exposed to large amounts of marine aerosols. In February and March, three events occurred more or less simultaneously: (1) leaf extension growth commenced; (2) chloride concentration surged in the leaf primordia; and (3) the leaf primordia began to hydrate. Following dormancy release, growth and hydration of leaf primordia were negatively related to chloride concentration in the leaf primordia, with inhibition of leaf growth, tissue hydration and chloride acquisition occurring at a chloride concentration threshold estimated at 7.3 mg Cl- g(-1) tissue water. Necrosis of leaf primordia was observed above 14 mg Cl- g(-1) tissue water. Growth and hydration of leaves at bud break in mid-May was explained by a three-parameter logistic model of chloride concentration in leaf primordia at the end of March. By mid-May, 90% of all buds remained non-necrotic, but only 56% the terminal buds had broken. Salt alone explained the observed growth suppression of leaf primordia in the buds and the resultant failure of terminal buds to break by mid-May.</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16585036?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Busov, Victor</style></author><author><style face="normal" font="default" size="100%">Meilan, Richard</style></author><author><style face="normal" font="default" size="100%">Pearce, David W</style></author><author><style face="normal" font="default" size="100%">Rood, Stewart B</style></author><author><style face="normal" font="default" size="100%">Ma, Caiping</style></author><author><style face="normal" font="default" size="100%">Tschaplinski, Timothy J</style></author><author><style face="normal" font="default" size="100%">Strauss, Steven H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Transgenic modification of gai or rgl1 causes dwarfing and alters gibberellins, root growth, and metabolite profiles in Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">Planta</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Planta</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jul</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">224</style></volume><pages><style face="normal" font="default" size="100%">288-99</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In Arabidopsis and other plants, gibberellin (GA)-regulated responses are mediated by proteins including GAI, RGA and RGL1-3 that contain a functional DELLA domain. Through transgenic modification, we found that DELLA-less versions of GAI (gai) and RGL1 (rgl1) in a Populus tree have profound, dominant effects on phenotype, producing pleiotropic changes in morphology and metabolic profiles. Shoots were dwarfed, likely via constitutive repression of GA-induced elongation, whereas root growth was promoted two- to threefold in vitro. Applied GA(3 )inhibited adventitious root production in wild-type poplar, but gai/rgl1 poplars were unaffected by the inhibition. The concentrations of bioactive GA(1) and GA(4) in leaves of gai- and rgl1-expressing plants increased 12- to 64-fold, while the C(19) precursors of GA(1) (GA(53), GA(44) and GA(19)) decreased three- to ninefold, consistent with feedback regulation of GA 20-oxidase in the transgenic plants. The transgenic modifications elicited significant metabolic changes. In roots, metabolic profiling suggested increased respiration as a possible mechanism of the increased root growth. In leaves, we found metabolite changes suggesting reduced carbon flux through the lignin biosynthetic pathway and a shift towards allocation of secondary storage and defense metabolites, including various phenols, phenolic glucosides, and phenolic acid conjugates.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16404575?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Melent'ev, A I</style></author><author><style face="normal" font="default" size="100%">Helisto, P</style></author><author><style face="normal" font="default" size="100%">Kuz'mina, L Iu</style></author><author><style face="normal" font="default" size="100%">Galimzianova, N F</style></author><author><style face="normal" font="default" size="100%">Aktuganov, G E</style></author><author><style face="normal" font="default" size="100%">Korpela, T</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[Application of Bacillus-antagonists for biocontrol of fungi degrading raw wood].</style></title><secondary-title><style face="normal" font="default" size="100%">Prikladnaia biokhimiia i mikrobiologiia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Prikl. Biokhim. Mikrobiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jan-Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">42</style></volume><pages><style face="normal" font="default" size="100%">70-5</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Species composition of micromycete complexes colonizing aspen, birch, and pine wood was studied. Calculation of the Sorens-Tchekanovsky similarity coefficients showed that these complexes shared a high degree of similarity. They were dominated by the representatives of the genera Penicillium, Paecilomyces, Trichoderma, and Rhizopus. Some antagonistic bacilli inhibited growth and development of wood-decay fungi in vitro and led to the formation of spheroplasts on growing hyphae. A study of possible involvement of bacillary mycolytic enzymes in the inhibition of wood-decay fungi demonstrated selectivity of their lytic effect, which was determined by the genus and species of micromycetes and did not correlate with their relative resistance to antagonists.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16521580?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Chefdor, Françoise</style></author><author><style face="normal" font="default" size="100%">Bénédetti, Hélène</style></author><author><style face="normal" font="default" size="100%">Depierreux, Christiane</style></author><author><style face="normal" font="default" size="100%">Delmotte, Francis</style></author><author><style face="normal" font="default" size="100%">Morabito, Domenico</style></author><author><style face="normal" font="default" size="100%">Carpin, Sabine</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Osmotic stress sensing in Populus: components identification of a phosphorelay system.</style></title><secondary-title><style face="normal" font="default" size="100%">FEBS letters</style></secondary-title><alt-title><style face="normal" font="default" size="100%">FEBS Lett.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jan 9</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">580</style></volume><pages><style face="normal" font="default" size="100%">77-81</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">To study the Populus response to an osmotic stress, we have isolated one cDNA encoding a histidine-aspartate kinase (HK1) and four cDNAs encoding histidine-containing phosphotransfer proteins (HPts), HPt1-4. The predicted HK1 protein shares a typical structure with ATHK1 and SLN1 osmosensors. The 4 HPTs are characterized by the histidine phosphotransfer domain. We have shown that HK1 is upregulated during an osmotic stress in hydroponic culture. We have detected an interaction between HK1 and HPt2, using the yeast two-hybrid system. These results suggest the existence of a multi-step phosphorelay pathway probably involved in osmotic stress sensing in Populus.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16359674?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Andersson-Gunnerås, Sara</style></author><author><style face="normal" font="default" size="100%">Mellerowicz, Ewa J</style></author><author><style face="normal" font="default" size="100%">Love, Jonathan</style></author><author><style face="normal" font="default" size="100%">Segerman, Bo</style></author><author><style face="normal" font="default" size="100%">Ohmiya, Yasunori</style></author><author><style face="normal" font="default" size="100%">Coutinho, Pedro M</style></author><author><style face="normal" font="default" size="100%">Nilsson, Peter</style></author><author><style face="normal" font="default" size="100%">Henrissat, Bernard</style></author><author><style face="normal" font="default" size="100%">Moritz, Thomas</style></author><author><style face="normal" font="default" size="100%">Sundberg, Björn</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Biosynthesis of cellulose-enriched tension wood in Populus: global analysis of transcripts and metabolites identifies biochemical and developmental regulators in secondary wall biosynthesis.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">45</style></volume><pages><style face="normal" font="default" size="100%">144-65</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Stems and branches of angiosperm trees form tension wood (TW) when exposed to a gravitational stimulus. One of the main characteristics of TW, which distinguishes it from normal wood, is the formation of fibers with a thick inner gelatinous cell wall layer mainly composed of crystalline cellulose. Hence TW is enriched in cellulose, and deficient in lignin and hemicelluloses. An expressed sequence tag library made from TW-forming tissues in Populus tremula (L.) x tremuloides (Michx.) and data from transcript profiling using microarray and metabolite analysis were obtained during TW formation in Populus tremula (L.) in two growing seasons. The data were examined with the aim of identifying the genes responsible for the change in carbon (C) flow into various cell wall components, and the mechanisms important for the formation of the gelatinous cell wall layer (G-layer). A specific effort was made to identify carbohydrate-active enzymes with a putative function in cell wall biosynthesis. An increased C flux to cellulose was suggested by a higher abundance of sucrose synthase transcripts. However, genes related to the cellulose biosynthetic machinery were not generally affected, although the expression of secondary wall-specific CesA genes was modified in both directions. Other pathways for which the data suggested increased activity included lipid and glucosamine biosynthesis and the pectin degradation machinery. In addition, transcripts encoding fasciclin-like arabinogalactan proteins were particularly increased and found to lack true Arabidopsis orthologs. Major pathways for which the transcriptome and metabolome analysis suggested decreased activity were the pathway for C flux through guanosine 5'-diphosphate (GDP) sugars to mannans, the pentose phosphate pathway, lignin biosynthesis, and biosynthesis of cell wall matrix carbohydrates. Several differentially expressed auxin- and ethylene-related genes and transcription factors were also identified.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16367961?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Swamy, S L</style></author><author><style face="normal" font="default" size="100%">Mishra, Alka</style></author><author><style face="normal" font="default" size="100%">Puri, S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Comparison of growth, biomass and nutrient distribution in five promising clones of Populus deltoides under an agrisilviculture system.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioresource technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bioresour. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">97</style></volume><pages><style face="normal" font="default" size="100%">57-68</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Variations in growth, above- and below-ground biomass and nutrient distribution were examined in five clones (G3, G48, 65/27, D121 and S7C1) of Populus deltoides grown under agrisilviculture system in sub-humid tropics of Central India. The monoclonal blocks were planted at 4x5 m in a randomized block design with three replications. Diameter at breast height (dbh) and tree height were consistently higher in clone 65/27 and lowest in clone S7C1. Mean annual increments (MAI) in dbh and height were 1.6 and 1.3 times higher in clone 65/27 compared to clone S7C1. Total biomass varied from 48.5 to 62.2 Mg ha(-1) in six-year-old clones. In rank order, the total biomass of clones was: 65/27&gt;D121&gt;G48&gt;G3&gt;S7C1. Stem wood accounted 60.4-68.9% to total biomass followed by coarse roots (12.2-18.9%), branches (12.3-15%), leaves (3.02-6.9%) and fine roots (1.5-2.7%). Root-shoot ratio ranged from 0.2 to 0.35. It was highest in clone G48 and lowest in clone S7C1. In six-year-old clones, total N ranged from 184.3 to 266.3 kg ha(-1), P from 16.8 to 31.1 kg ha(-1) and K from 81.9 to 128.7 kg ha(-1). Total N and P were highest in clone 65/27, while K in clone G48. Nutrients were lowest in clone S7C1. In general, maximum nutrients (N, P and K) were allocated to above-ground components (leaves&gt;stem&gt;branches) than below-ground components. Available N, P and K in the soil improved significantly after six years of planting. It was higher in 0-20 cm and decreased with soil depth. At 0-20 cm soil depth, N increased from 14.9% to 24.1%, P from 17.2% to 23.3% and K from 3.1% to 5.1% under different clones. The yield of both soybean and wheat reduced under poplar clones. Yield losses in soybean ranged from 10.1% to 33% and wheat from 15% to 30.3% under different clones. The management strategies for reducing tree-crop competition and nutrient export from the site under P. deltoides based agrisilviculture system for achieving sustainable production are discussed.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16154503?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sampedro, Javier</style></author><author><style face="normal" font="default" size="100%">Carey, Robert E</style></author><author><style face="normal" font="default" size="100%">Cosgrove, Daniel J</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genome histories clarify evolution of the expansin superfamily: new insights from the poplar genome and pine ESTs.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of plant research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Plant Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">119</style></volume><pages><style face="normal" font="default" size="100%">11-21</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Expansins comprise a superfamily of plant cell wall-loosening proteins that has been divided into four distinct families, EXPA, EXPB, EXLA and EXLB. In a recent analysis of Arabidopsis thaliana and Oryza sativa expansins, we proposed a further subdivision of the families into 17 clades, representing independent lineages in the last common ancestor of monocots and eudicots. This division was based on both traditional sequence-based phylogenetic trees and on position-based trees, in which genomic locations and dated segmental duplications were used to reconstruct gene phylogeny. In this article we review recent work concerning the patterns of expansin evolution in angiosperms and include additional insights gained from the genome of a second eudicot species, Populus trichocarpa, which includes at least 36 expansin genes. All of the previously proposed monocot-eudicot orthologous groups, but no additional ones, are represented in this species. The results also confirm that all of these clades are truly independent lineages. Furthermore, we have used position-based phylogeny to clarify the history of clades EXPA-II and EXPA-IV. Most of the growth of the expansin superfamily in the poplar lineage is likely due to a recent polyploidy event. Finally, some monocot-eudicot clades are shown to have diverged before the separation of the angiosperm and gymnosperm lineages.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16411016?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wu, Rongling</style></author><author><style face="normal" font="default" size="100%">Hou, Wei</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A hyperspace model to decipher the genetic architecture of developmental processes: allometry meets ontogeny.</style></title><secondary-title><style face="normal" font="default" size="100%">Genetics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Genetics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">172</style></volume><pages><style face="normal" font="default" size="100%">627-37</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">To better utilize limited resources for their survival and reproduction, all organisms undergo developmental changes in both body size and shape during ontogeny. The genetic analysis of size change with increasing age, i.e., growth, has received considerable attention in quantitative developmental genetic studies, but the genetic architecture of ontogenetic changes in body shape and its associated allometry have been poorly understood partly due to the lack of analytical tools. In this article, we attempt to construct a multivariate statistical framework for studying the genetic regulation of ontogenetic growth and shape. We have integrated biologically meaningful mathematical functions of growth curves and developmental allometry into the estimation process of genetic mapping aimed at identifying individual quantitative trait loci (QTL) for phenotypic variation. This model defined with high dimensions can characterize the ontogenetic patterns of genetic effects of QTL over the lifetime of an organism and assess the interplay between genetic actions/interactions and phenotypic integration. The closed forms for the residual covariance matrix and its determinant and inverse were derived to overcome the computational complexity typical of our high-dimensional model. We used a worked example to validate the utility of this model. The implications of this model for genetic research of evo-devo are discussed.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16157673?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bailey, Joseph K</style></author><author><style face="normal" font="default" size="100%">Wooley, Stuart C</style></author><author><style face="normal" font="default" size="100%">Lindroth, Richard L</style></author><author><style face="normal" font="default" size="100%">Whitham, Thomas G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Importance of species interactions to community heritability: a genetic basis to trophic-level interactions.</style></title><secondary-title><style face="normal" font="default" size="100%">Ecology letters</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ecol. Lett.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">9</style></volume><pages><style face="normal" font="default" size="100%">78-85</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Recent community genetics studies have shown that specific genotypes of a host plant support distinct arthropod communities. Building upon these findings, we examined the hypothesis that a trophic community consisting of cottonwood trees, a galling herbivore and avian predators could also be related to the genetics of the host tree. We found genetic correlations among phytochemistry of individual tree genotypes, the density of a galling herbivore, and the intensity of avian predation on these herbivores. We detected significant broad-sense heritability of these interactions that range from H(B)2 = 0.70 to 0.83. The genetic basis of these interactions tended to increase across trophic levels suggesting that small genetic changes in the cottonwood phenotype could have major consequences at higher trophic levels affecting species interactions and energy flow. These findings show a heritable basis to trophic-level interactions indicating that there is a significant genetic basis to community composition and energy flow that is predictable by plant genotype. Our data clearly link plant genetics to patterns of avian foraging and show that species interactions are important components of community heritability and ecosystem processes. Overall, these data support the hypothesis that evolution of plant traits can alter trophic-level interactions and community composition.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16958871?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">LeRoy, Carri J</style></author><author><style face="normal" font="default" size="100%">Whitham, Thomas G</style></author><author><style face="normal" font="default" size="100%">Keim, Paul</style></author><author><style face="normal" font="default" size="100%">Marks, Jane C</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Plant genes link forests and streams.</style></title><secondary-title><style face="normal" font="default" size="100%">Ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ecology</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Jan</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">87</style></volume><pages><style face="normal" font="default" size="100%">255-61</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Although it is understood that the composition of riparian trees can affect stream function through leaf litter fall, the potential effects of genetic variation within species are less understood. Using a naturally hybridizing cottonwood system, we examined the hypothesis that genetic differences among two parental species (Populus fremontii and P. angustifolia) and two groups of their hybrids (F1 and backcrosses to P. angustifolia) would affect litter decomposition rates and the composition of the aquatic invertebrate community that colonizes leaves. Three major findings emerged: (1) parental and hybrid types differ in litter quality, (2) decomposition differs between two groups, a fast group (P. fremontii and F1 hybrid), and a slow group (P. angustifolia and backcross hybrids), and (3) aquatic invertebrate communities colonizing P. fremontii litter differed significantly in composition from all other cross types, even though P. fremontii and the F1 hybrid decomposed at similar rates. These findings are in agreement with terrestrial arthropod studies in the same cottonwood system. However, the effects are less pronounced aquatically than those observed in the adjacent terrestrial community, which supports a genetic diffusion hypothesis. Importantly, these findings argue that genetic interactions link terrestrial and aquatic communities and may have significant evolutionary and conservation implications.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16634316?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hüve, Katja</style></author><author><style face="normal" font="default" size="100%">Bichele, Irina</style></author><author><style face="normal" font="default" size="100%">Tobias, Mari</style></author><author><style face="normal" font="default" size="100%">Niinemets, Ulo</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Heat sensitivity of photosynthetic electron transport varies during the day due to changes in sugars and osmotic potential.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">212-28</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In water-stressed leaves, accumulation of neutral osmotica enhances the heat tolerance of photosynthetic electron transport. There are large diurnal and day-to-day changes in leaf sugar content because of variations in net photosynthetic production, respiration and retranslocation. To test the hypothesis that diurnal and day-to-day variations in leaf sugar content and osmotic potential significantly modify the responses to temperature of photosynthetic electron transport rate, we studied chlorophyll fluorescence rise temperatures (i.e. critical temperatures at break-points in fluorescence versus temperature response curves, corresponding to enhanced damage of PSII centers and detachment of pigment-binding complexes) in the dark at a background of weak far-red light (T(FR)) and under actinic light (T(L)), and responses of foliar photosynthetic electron transport rate to temperature using gas-exchange and chlorophyll fluorescence techniques in the temperate tree Populus tremula L. Sucrose and sorbitol feeding experiments demonstrated strong increases of fluorescence rise temperatures T(FR) and T(L) with decreasing leaf osmotic potential and increasing internal sugar concentration. Similar T(FR) and T(L) changes were observed in response to natural variation in leaf sugar concentration throughout the day. Increases in leaf sugar concentration led to an overall down-regulation of the rate of photosynthetic electron transport (J), but increases in the optimum temperature (Topt) of J. For the entire dataset, Topt varied from 33.8 degrees C to 43 degrees C due to natural variation in sugars and from 33.8 degrees C to 52.6 degrees C in the sugar feeding experiments, underscoring the importance of sugars in modifying the response of J to temperature. However, the correlations between the sugar concentration and fluorescence rise temperature varied between the days. This variation in fluorescence rise temperature was best explained by the average temperature of the preceding 5 or 6 days. In addition, there was a significant year-to-year variation in heat sensitivity of photosynthetic electron transport that was associated with year-to-year differences in endogenous sugar content. Our data demonstrate a diurnal variation in leaf heat tolerance due to changes in sugar concentration, but they also show that this short-term modification in heat tolerance is super-imposed by long-term changes in heat resistance driven by average temperature of preceding days.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17080637?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Tenczar, Emily G</style></author><author><style face="normal" font="default" size="100%">Krischik, Vera A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Management of cottonwood leaf beetle (Coleoptera: Chrysomelidae) with a novel transplant soak and biorational insecticides to conserve coccinellid beetles.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of economic entomology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Econ. Entomol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">99</style></volume><pages><style face="normal" font="default" size="100%">102-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Biorational foliar sprays and a novel application method of soaking transplants in imidacloprid were evaluated for control of adult and larval cottonwood leaf beetle, Chrysomela scripta F., on hybrid poplar, with emphasis on conservation of coccinellid predators. Foliar sprays of four biorational insecticides killed adult and larval C. scripta: Bacillus thuringiensis (B.t.) variety tenebrionis (Novodor), B.t. variety kurstaki (Raven), spinosad (Conserve SC), and azadirachtin (Azatin XL) (larvae only) but did not kill two species of coccinellids, Hippodamia convergens Guérin-Meneville and Harmonia axyridis (Pallas). Only imidacloprid (Admire 2) and carbaryl (Sevin XLR Plus) killed two species of coccinellids and adult and larval C. scripta. We evaluated a novel stick soak method for systemically applying imidacloprid by soaking poplar sticks in Admire 2 solutions of 3 and 6 ml/liter for 48 h before planting. The imidacloprid in the sticks was translocated to the leaves and reduced survivorship of adult and larval C. scripta for 10 mo without any symptoms of phytotoxicity. The novel stick soak method did not kill two species of coccinellids when foraging on leaves.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16573329?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lee, Philip</style></author><author><style face="normal" font="default" size="100%">Boutin, Stan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Persistence and developmental transition of wide seismic lines in the western Boreal Plains of Canada.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of environmental management</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Environ. Manage.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">78</style></volume><pages><style face="normal" font="default" size="100%">240-50</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">This study examined the fate of seismic lines utilized in oil and gas exploration in Canada's western Boreal Plains. It retrospectively followed the persistence, recovery and developmental transition of seismic lines established between the 1960s and the mid-1970s through to 2003. We examined lines that passed through three forest types; aspen, white spruce, and lowland black spruce. In general, the recovery rates of seismic lines to woody vegetation were low. After 35 years, 8.2% of seismic lines across all forest types had recovered to greater than 50% cover of woody vegetation. Only the upland forest types recovered; aspen and white spruce. Most seismic lines ( approximately 65% at 35 years) remained in a cleared state with a cover of low forbs. The most common transition for seismic lines was to tracked access ( approximately 20% at 35 years). Transition to other anthropogenic developments such as roads, pipelines, buildings, and timber harvest blocks was 5% after 35 years. The pulse of industrial activity initiated in the mid-1990s greatly increased the transition rate of seismic to tracked access for a short period of time. The discussion focused on natural and anthropogenic factors that hinder recovery and on the management directions that would facilitate greater recovery rates.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16112795?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Du, Juan</style></author><author><style face="normal" font="default" size="100%">Xie, Hong-Li</style></author><author><style face="normal" font="default" size="100%">Zhang, De-Qiang</style></author><author><style face="normal" font="default" size="100%">He, Xin-Qiang</style></author><author><style face="normal" font="default" size="100%">Wang, Min-Jie</style></author><author><style face="normal" font="default" size="100%">Li, Ying-Zhang</style></author><author><style face="normal" font="default" size="100%">Cui, Ke-Ming</style></author><author><style face="normal" font="default" size="100%">Lu, Meng-Zhu</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Regeneration of the secondary vascular system in poplar as a novel system to investigate gene expression by a proteomic approach.</style></title><secondary-title><style face="normal" font="default" size="100%">Proteomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Proteomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">6</style></volume><pages><style face="normal" font="default" size="100%">881-95</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Wood formation is a complex process composing many biological events. To access its key developmental stages, we have established a regeneration system that can mimic the initiation and differentiation of cambium cells for Chinese white poplar. Anatomical studies showed that new cambium and xylem re-appeared in sequence within a few weeks after being debarked. This provides the opportunity to follow key stages of wood formation by sampling clonal trees at different regeneration times. We used this system in combination with a proteomic approach to analyze proteins expressed in different regeneration stages. PMFs for 244 proteins differentially displayed were obtained and queried against public databases. Putative functions of 199 of these proteins were assigned and classified. Regulatory genes for cell cycle progression, differentiation and cell fate were expressed in the formation of cambial tissue, while 27 genes involved in secondary wall formation were predominantly found in the xylem developing stage. This indicates that the change of gene expression pattern is corresponding to the progression of second vascular system regeneration when and where the key events of wood development occur. Further exploration of these interesting genes may provide insight into the molecular mechanisms of wood formation.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16385474?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Pearce, David W</style></author><author><style face="normal" font="default" size="100%">Millard, Sandra</style></author><author><style face="normal" font="default" size="100%">Bray, Douglas F</style></author><author><style face="normal" font="default" size="100%">Rood, Stewart B</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Stomatal characteristics of riparian poplar species in a semi-arid environment.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">26</style></volume><pages><style face="normal" font="default" size="100%">211-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Several native poplar species meet at the margins of their natural distributions in southern Alberta, Canada. In this semi-arid area, poplars are obligate riparian species but they occupy several intergrading ecoregions. Populus deltoides Bartr. ex Marsh predominates in the warmest and driest eastern prairie ecoregions; P. balsamifera L. occupies the cooler and wetter western parkland and montane ecoregions; and P. angustifolia James and hybrids between the species occur in the intermediate grassland ecoregions. We investigated stomatal characteristics of these poplars in 51 genotypes collected across the range of ecoregions and grown in a semi-arid common garden. Stomatal length differed among genotypes within species but did not differ among species, ranging from 19 to 22 microm. Total stomatal densities (adaxial plus abaxial) differed among genotypes within species but were similar among species (290-420 stomata mm(-2)). Single-surface stomatal densities differed among species and consequently, the ratio of adaxial:abaxial stomatal density also differed, ranging from 0.94 for P. deltoides to 0.27 for P. balsamifera, with intermediate stomatal density ratios in P. angustifolia and hybrids. In a subsequent study of a subset of the same genotypes, stomatal density was correlated with stomatal conductance (r2 = 0.75) and the conductance ratios differed among species in the same manner as the stomatal density ratios. We conclude that: (1) diverse poplar genotypes respond similarly to a semi-arid environment by producing comparatively small and dense stomata; (2) differences in stomatal density underlie differences in stomatal conductance and differences among species in stomatal density ratio or conductance ratio may reflect adaptation to climatic differences among ecoregions; and (3) there is substantial variation in stomatal characteristics within and among species and hybrids in this area that could be useful for the selection and breeding of poplars adapted to different climatic conditions.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16356918?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Frankenstein, C</style></author><author><style face="normal" font="default" size="100%">Schmitt, U</style></author><author><style face="normal" font="default" size="100%">Koch, G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Topochemical studies on modified lignin distribution in the xylem of Poplar (Populus spp.) after wounding.</style></title><secondary-title><style face="normal" font="default" size="100%">Annals of botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ann. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Feb</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">97</style></volume><pages><style face="normal" font="default" size="100%">195-204</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Information on the influence of wounding on lignin synthesis and distribution in differentiating xylem tissue is still scarce. The present paper provides information on cell modifications with regard to wall ultrastructure and lignin distribution on cellular and subcellular levels in poplar after wounding.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16354725?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lagomarsino, A</style></author><author><style face="normal" font="default" size="100%">Moscatelli, M C</style></author><author><style face="normal" font="default" size="100%">De Angelis, P</style></author><author><style face="normal" font="default" size="100%">Grego, S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Labile substrates quality as the main driving force of microbial mineralization activity in a poplar plantation soil under elevated CO2 and nitrogen fertilization.</style></title><secondary-title><style face="normal" font="default" size="100%">The Science of the total environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Sci. Total Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Dec 15</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">372</style></volume><pages><style face="normal" font="default" size="100%">256-65</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Soil carbon (C) long term storage is influenced by the balance among ecosystem net primary productivity (NPP), the rate of delivery of new organic matter to soil pools and the decomposition of soil organic matter (SOM). The increase of NPP under elevated CO(2) can result in a greater production and higher turnover of fine roots or root exudation and, in turn, in an increase of labile C belowground. The aim of this work was to detect if changes in labile C substrates influenced the organic C storage in soils, verifying (i) whether treatments with elevated CO(2) and N fertilization induced changes in the amount and quality of labile C pools and in microbial C immobilization and (ii) whether these changes provoked modifications in the microbial C mineralization activity, and therefore changes in soil C losses. The effect of elevated CO(2) was a significant increase in both seasons (June and October 2004), of all labile C fractions: microbial biomass C (MBC), K(2)SO(4) extractable C (ExC), and water soluble C (WSC). The C/N ratio of the microbial biomass and of the K(2)SO(4) extractable SOM presented a seasonal fluctuation showing higher values in June, whereas the elevated CO(2) increased significantly the C/N ratio of these fractions independent of the season and the N addition, indicating a lower quality of labile SOM. Microbial respiration was more than doubled in October compared to June, confirming that changes in substrate quality and nutrient availability, occurring in the plantation at the beginning and at the end of the vegetative period, influenced the microbial activity in the bulk soil. Furthermore, the microbial respiration response to N fertilization was dependent on the season, with an opposite effect between June and October. The kinetic parameters calculated according to the first-order equation C(m)=C(0)(1-e(-kt)) were unaffected by elevated CO(2) treatment, except C(0)k and MR(basal), that showed a significant reduction, ascribable to (i) a lower quality of labile pools, and (ii) a more efficient microbial biomass in the use of available substrates. The C surplus found in elevated CO(2) soils was indeed immobilized and used for microbial growth, thus excluding a priming effect mechanism of elevated CO(2) on SOM decomposition.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17023027?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Yifru, Dawit D</style></author><author><style face="normal" font="default" size="100%">Nzengung, Valentine A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Uptake of N-nitrosodimethylamine (NDMA) from water by phreatophytes in the absence and presence of perchlorate as a co-contaminant.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental science &amp; technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Environ. Sci. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Dec 1</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">40</style></volume><pages><style face="normal" font="default" size="100%">7374-80</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The uptake and fate of the emerging contaminants N-nitrosodimethylamine (NDMA) and perchlorate in phreatophytes was studied in a hydroponics system under greenhouse conditions. NDMA is a potent carcinogen, and perchlorate disrupts the functioning ofthe human thyroid gland. The rate of removal of NDMA from solution by rooted cuttings of black willow (Salix nigra) and hybrid poplar (Populus deltoides x nigra, DN34) trees varied seasonally, with faster removal in summer months when transpiration rates were highest. A linear correlation between the volume of water transpired and mass of NDMA removed from the root zone was observed, especially at higher NDMA concentrations. In bioreactors dosed with both NDMA (0.7-1.0 mg L(-1)) and perchlorate (27 mg L(-1)), no competitive uptake of NDMA and perchlorate was observed. While NDMA was primarily removed from solution by plant uptake, perchlorate was predominantly removed by rhizodegradation. In the presence of NDMA, a slower rate of rhizodegradation of perchlorate was observed, but still significantly faster than the rate of NDMA uptake. For experiments conducted with radiolabeled NDMA, 46.4 +/- 1.1% of the total 14C-activity was recovered in the plant tissues and 47.5% was phytovolatilized. The 46.4 +/- 1.1% recovered in the plants was distributed as follows: 18.8 +/- 1.4% in leaves, 15.9 +/- 5.9% in stems, 7.6 +/- 3.2% in branches, and 3.5 +/- 3.3% in roots. The poor extractability of NDMA with methanol-water (1:1 v/v) from stem and leaf tissues suggested that some fraction of NDMA was assimilated. The calculated transpiration stream concentration factor (TSCF) of 0.28 +/- 0.06 suggests that NDMA is passively taken up by phreatophytes, and mainly phytovolatilized.</style></abstract><issue><style face="normal" font="default" size="100%">23</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17180991?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Zhang, XinFeng</style></author><author><style face="normal" font="default" size="100%">Hung, Tran Manh</style></author><author><style face="normal" font="default" size="100%">Phuong, Phuong Thien</style></author><author><style face="normal" font="default" size="100%">Ngoc, Tran Minh</style></author><author><style face="normal" font="default" size="100%">Min, Byung-Sun</style></author><author><style face="normal" font="default" size="100%">Song, Kyung-Sik</style></author><author><style face="normal" font="default" size="100%">Seong, Yeon Hee</style></author><author><style face="normal" font="default" size="100%">Bae, KiHwan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Anti-inflammatory activity of flavonoids from Populus davidiana.</style></title><secondary-title><style face="normal" font="default" size="100%">Archives of pharmacal research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Arch. Pharm. Res.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">1102-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">An in vitro bioassay-guide revealed that the methanol (MeOH) extract of the stem bark of Populus davidiana showed considerable inhibitory activity against cyclooxygenase (COX-1, COX-2). Continuous phytochemical study of the MeOH extract of this plant led to the isolation of ten flavonoids; sakuranetin (1), rhamnocitrin (2), 7-O-methylaromadendrin (3), naringenin (4), eriodictyol (5), aromadendrin (6), kaempferol (7), neosakuranin (8), sakuranin (9) and sakurenetin-5,4'-di-beta-D-glucopyranoside (10). Their structures were identified on the basis of their physicochemical and spectroscopic analyses. The isolated compounds, 1-10, were tested for their inhibitory activities against COX-1 and COX-2. Compound 7 was found to have potent inhibitory effect on COX-1 and a moderate effect on COX-2, meanwhile, compounds 1-6 showed moderate inhibition against COX-1 only. Moreover, compounds 5-8 exhibited suppressive effects on xanthine oxidase (XO). These results may explain, in part, the traditional uses of P. davidiana in ethnomedicine.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17225458?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sasaki, Shinya</style></author><author><style face="normal" font="default" size="100%">Baba, Kei'ichi</style></author><author><style face="normal" font="default" size="100%">Nishida, Tomoaki</style></author><author><style face="normal" font="default" size="100%">Tsutsumi, Yuji</style></author><author><style face="normal" font="default" size="100%">Kondo, Ryuichiro</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The cationic cell-wall-peroxidase having oxidation ability for polymeric substrate participates in the late stage of lignification of Populus alba L.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Mol. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">62</style></volume><pages><style face="normal" font="default" size="100%">797-807</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Previously we reported that purified Cell Wall Peroxidase-Cationic (CWPO-C) from poplar callus (Populus alba L.) oxidizes sinapyl alcohol and polymeric substrate unlike other plant peroxidases and proposed that this isoenzyme is a conceivable lignification specific peroxidase. In this study, we cloned full-length cDNA of CWPO-C and investigated the transcription of CWPO-C gene in various organs and the localization of CWPO-C protein in the differentiating xylem of poplar stem.Real-time PCR analyses indicated that CWPO-C gene is constitutively expressed in the developing xylem, leaf, and shoot but not affected by many stress treatments. Immunohistochemical analysis showed that CWPO-C locates in the middle lamellae, cell corners, and secondary cell walls of the fiber cells during the lignification. The intensity of the CWPO-C labeling increased gradually from the cell wall thickening stage to mature stage of fiber cells, which is very consistent with the increase of lignin content in the developing xylem. These results strongly support that CWPO-C is responsible for the lignification of the secondary xylem. Interestingly, immuno-labeling of CWPO-C was also observed inside of the ray parenchyma cells instead no signals were detected within the developing fiber cells. This suggests that CWPO-C is biosynthesized in the parenchyma cells and provided to the middle lamellae, the cell corners, and the cell walls to achieve lignin polymerization.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17004015?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Plomion, Christophe</style></author><author><style face="normal" font="default" size="100%">Lalanne, Céline</style></author><author><style face="normal" font="default" size="100%">Claverol, Stéphane</style></author><author><style face="normal" font="default" size="100%">Meddour, Hakim</style></author><author><style face="normal" font="default" size="100%">Kohler, Annegret</style></author><author><style face="normal" font="default" size="100%">Bogeat-Triboulot, Marie-Béatrice</style></author><author><style face="normal" font="default" size="100%">Barre, Aurélien</style></author><author><style face="normal" font="default" size="100%">Le Provost, Grégoire</style></author><author><style face="normal" font="default" size="100%">Dumazet, Hélène</style></author><author><style face="normal" font="default" size="100%">Jacob, Daniel</style></author><author><style face="normal" font="default" size="100%">Bastien, Catherine</style></author><author><style face="normal" font="default" size="100%">Dreyer, Erwin</style></author><author><style face="normal" font="default" size="100%">de Daruvar, Antoine</style></author><author><style face="normal" font="default" size="100%">Guehl, Jean-Marc</style></author><author><style face="normal" font="default" size="100%">Schmitter, Jean-Marie</style></author><author><style face="normal" font="default" size="100%">Martin, Francis</style></author><author><style face="normal" font="default" size="100%">Bonneu, Marc</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Mapping the proteome of poplar and application to the discovery of drought-stress responsive proteins.</style></title><secondary-title><style face="normal" font="default" size="100%">Proteomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Proteomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">6</style></volume><pages><style face="normal" font="default" size="100%">6509-27</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Poplar is the first forest tree genome to be decoded. As an initial step to the comprehensive analysis of poplar proteome, we described reference 2-D-maps for eight tissues/organs of the plant, and the functional characterization of some proteins. A total of 398 proteins were excised from the gels. About 91.2% were identified by nanospray LC-MS/MS, based on comparison with 260,000 Populus sp. ESTs. In comparison, reliable PMFs were obtained for only 51% of the spots by MALDI-TOF-MS, from which 43% (83 spots) positively matched gene models of the Populus trichocarpa genome sequence. Among these 83 spots, 58% matched with the same proteins as identified by LC-MS/MS, 21.7% with unknown function proteins and 19.3% with completely different functions. In the second phase, we studied the effect of drought stress on poplar root and leaf proteomes. The function of up- and down-regulated proteins is discussed with respect to the physiological response of the plants and compared with transcriptomic data. Some important clues regarding the way poplar copes with water deficit were revealed.</style></abstract><issue><style face="normal" font="default" size="100%">24</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17163438?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Eberhardt, Thomas L</style></author><author><style face="normal" font="default" size="100%">Min, Soo-Hong</style></author><author><style face="normal" font="default" size="100%">Han, James S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Phosphate removal by refined aspen wood fiber treated with carboxymethyl cellulose and ferrous chloride.</style></title><secondary-title><style face="normal" font="default" size="100%">Bioresource technology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Bioresour. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">97</style></volume><pages><style face="normal" font="default" size="100%">2371-6</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Biomass-based filtration media are of interest as an economical means to remove pollutants and nutrients found in stormwater runoff. Refined aspen wood fiber samples treated with iron salt solutions demonstrated limited capacities to remove (ortho)phosphate from test solutions. To provide additional sites for iron complex formation, and thereby impart a greater capacity for phosphate removal, a fiber pretreatment with an aqueous solution of a non-toxic anionic polymer, carboxymethyl cellulose (CMC), was evaluated. Problems with excessive viscosities during the screening of commercially available CMC products led to the selection of an ultra low viscosity CMC product that was still usable at a 4% concentration in water. Soxhlet extractions of chipped aspen wood and refined aspen wood fiber samples showed a higher extractives content for the refined material. Analysis of these extracts by FTIR spectroscopy suggested that the higher extractives content for the refined material resulted from the fragmentation of cell wall polymers (e.g., lignin, hemicelluloses) normally insoluble in their native states. Spectroscopic analysis of CMC and ferrous chloride treated fibers showed that the complex formed was sufficiently stable to resist removal during subsequent water washes. Equilibrium sorption data, which fit better with a Freundlich isotherm model than a Langmuir isotherm model, showed that phosphate removal could be enhanced by the CMC pretreatment. Results suggest that the process outlined may provide a facile means to improve the phosphate removal capacity of biomass-based stormwater filtration media.</style></abstract><issue><style face="normal" font="default" size="100%">18</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16361096?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gregg, Jillian W</style></author><author><style face="normal" font="default" size="100%">Jones, Clive G</style></author><author><style face="normal" font="default" size="100%">Dawson, Todd E</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Physiological and developmental effects of O3 on cottonwood growth in urban and rural sites.</style></title><secondary-title><style face="normal" font="default" size="100%">Ecological applications : a publication of the Ecological Society of America</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ecol Appl</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">16</style></volume><pages><style face="normal" font="default" size="100%">2368-81</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Previously we found that cloned cottonwood saplings (Populus deltoides) grew twice as large in New York, New York, USA, compared to surrounding rural environments and that soils, temperature, CO2, nutrient deposition, and microclimatic variables could not account for the greater urban plant biomass. Correlations between final season biomass and cumulative O3 exposures, combined with twofold growth reductions in an open-top chamber experiment provided strong evidence that higher cumulative O3 exposures in rural sites reduced growth in the country. Here, we assess the field gas exchange, growth and development, and allocation responses underlying the observed growth differences and compare them with isolated O3 responses documented in the open-top chamber experiment. Cottonwoods showed no visible foliar injury, reduced photosynthesis of recently expanded foliage, early leaf senescence, protective reduction in stomatal conductance, or compensatory allocation to shoot relative to root biomass for either the chamber or field experiment. Instead, O3-impacted chamber plants had significantly higher conductance and reduced photosynthesis of older foliage that led to reduced leaf area production and a twofold biomass reduction in the absence of visible injury. Rural-grown field plants showed the same pattern of significantly higher conductance in the absence of concomitant increases in photosynthesis that was indicative of a loss of stomatal control. Incremental changes in foliar production were also significantly inversely related to fluctuations in ambient O3 exposures. The similarity in biomass, gas exchange, phenological, and allocation responses between chamber and field experiments indicate that mechanisms accounting for reduced growth at rural sites were consistent with those in the open-top chamber O3 experiment. This study shows the limitation of visible symptoms as a sole diagnostic factor for documenting detrimental O3 impacts and points toward a new approach to show O3 impacts when visible injury is not present. Namely, O3-impacted vegetation showed an unusual inverse relationship of increased conductance with lower photosynthesis of older foliage that was indicative of a loss of stomatal control. This increased stomatal conductance of O3-impacted vegetation accentuates pollutant flux into affected foliage and has important implications for system water balance during warm, dry portions of the growing season when O3 concentrations are highest.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17205911?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Navrot, Nicolas</style></author><author><style face="normal" font="default" size="100%">Collin, Valérie</style></author><author><style face="normal" font="default" size="100%">Gualberto, José</style></author><author><style face="normal" font="default" size="100%">Gelhaye, Eric</style></author><author><style face="normal" font="default" size="100%">Hirasawa, Masakazu</style></author><author><style face="normal" font="default" size="100%">Rey, Pascal</style></author><author><style face="normal" font="default" size="100%">Knaff, David B</style></author><author><style face="normal" font="default" size="100%">Issakidis, Emmanuelle</style></author><author><style face="normal" font="default" size="100%">Jacquot, Jean-Pierre</style></author><author><style face="normal" font="default" size="100%">Rouhier, Nicolas</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Plant glutathione peroxidases are functional peroxiredoxins distributed in several subcellular compartments and regulated during biotic and abiotic stresses.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">142</style></volume><pages><style face="normal" font="default" size="100%">1364-79</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We provide here an exhaustive overview of the glutathione (GSH) peroxidase (Gpx) family of poplar (Populus trichocarpa). Although these proteins were initially defined as GSH dependent, in fact they use only reduced thioredoxin (Trx) for their regeneration and do not react with GSH or glutaredoxin, constituting a fifth class of peroxiredoxins. The two chloroplastic Gpxs display a marked selectivity toward their electron donors, being exclusively specific for Trxs of the y type for their reduction. In contrast, poplar Gpxs are much less specific with regard to their electron-accepting substrates, reducing hydrogen peroxide and more complex hydroperoxides equally well. Site-directed mutagenesis indicates that the catalytic mechanism and the Trx-mediated recycling process involve only two (cysteine [Cys]-107 and Cys-155) of the three conserved Cys, which form a disulfide bridge with an oxidation-redox midpoint potential of -295 mV. The reduction/formation of this disulfide is detected both by a shift on sodium dodecyl sulfate-polyacrylamide gel electrophoresis or by measuring the intrinsic tryptophan fluorescence of the protein. The six genes identified coding for Gpxs are expressed in various poplar organs, and two of them are localized in the chloroplast, with one colocalizing in mitochondria, suggesting a broad distribution of Gpxs in plant cells. The abundance of some Gpxs is modified in plants subjected to environmental constraints, generally increasing during fungal infection, water deficit, and metal stress, and decreasing during photooxidative stress, showing that Gpx proteins are involved in the response to both biotic and abiotic stress conditions.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17071643?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kosola, Kevin R</style></author><author><style face="normal" font="default" size="100%">Parry, Dylan</style></author><author><style face="normal" font="default" size="100%">Workmaster, Beth Ann A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Responses of condensed tannins in poplar roots to fertilization and gypsy moth defoliation.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">26</style></volume><pages><style face="normal" font="default" size="100%">1607-11</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We examined the effects of fertilization and gypsy moth defoliation on condensed tannin concentration (%CT) of hybrid poplar (Populus x canadensis cv 'Eugeneii') fine roots in the summers of 1997 and 1998. This factorial experiment included two defoliation treatments (defoliated and a foliated control) and fertilization treatments (100 kg nitrogen (N) ha(-1) and an unfertilized control). Gypsy moth (Lymantria dispar L.) populations were experimentally increased to obtain defoliation in the summers of 1996, 1997 and 1998; fertilization subplots were supplemented with NH4NO3 (100 kg N ha(-1)) in the spring of each year. Despite the severity of defoliation, the effects were small, and significant on only two sampling dates: in May 1997, when fine root %CT was 23% lower in the defoliated trees, and in November 1997, when trees in the defoliated unfertilized plots had 35% higher root %CT than trees in all other plots. Defoliation effects on root %CT did not follow the same seasonal pattern as defoliation effects on root starch content, N uptake capacity or leaf %CT. Regulation of root condensed tannin concentration appeared to be partially uncoupled from these traits. The small transient effects on root defense reflect the resilience of this early successional tree to severe early season defoliation.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17169900?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kendrick, Alexander P</style></author><author><style face="normal" font="default" size="100%">Raffa, Kenneth F</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Sources of insect and plant volatiles attractive to cottonwood leaf beetles feeding on hybrid poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of chemical ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Chem. Ecol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">32</style></volume><pages><style face="normal" font="default" size="100%">2585-94</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The cottonwood leaf beetle, Chrysomela scripta, is the most damaging insect affecting the production of Populus, an important source of sustainable forest products and biomass. Currently, there is no simple method for monitoring C. scripta populations, and nothing is known about potential chemical attractants for trapping. We conducted laboratory assays on sources of attraction to C. scripta adults. In olfactometer trials, beetles were attracted to volatiles released from conspecifics feeding on foliage. There was also significant, but lesser, attraction to odor from unwounded foliage, C. scripta alone, and frass. The latter two results indicate the presence of a pheromone. Wounding of foliage by C. scripta, but not by artificial means, enhanced its attractiveness compared to unwounded foliage, even when C. scripta by-products were removed. In direct comparisons, responses to odor from beetle-wounded foliage were not different from responses to odor from beetles feeding on foliage. We tested the attractiveness of volatiles emitted by adults feeding on foliage in the field using modified boll weevil traps. Results confirm that these volatiles are sufficient to increase trap catches in the field. Color is also important, with yellow baited traps catching more beetles than black baited. We propose that original landing by C. scripta is mediated by host odors and visual cues and that subsequent aggregation is enhanced by chemical cues associated with feeding by conspecifics. This may partially explain clustering in the field and likewise be incorporated into sampling schemes needed for integrated pest management.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17089182?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sjödin, Andreas</style></author><author><style face="normal" font="default" size="100%">Bylesjö, Max</style></author><author><style face="normal" font="default" size="100%">Skogström, Oskar</style></author><author><style face="normal" font="default" size="100%">Eriksson, Daniel</style></author><author><style face="normal" font="default" size="100%">Nilsson, Peter</style></author><author><style face="normal" font="default" size="100%">Rydén, Patrik</style></author><author><style face="normal" font="default" size="100%">Jansson, Stefan</style></author><author><style face="normal" font="default" size="100%">Karlsson, Jan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">UPSC-BASE--Populus transcriptomics online.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant journal : for cell and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Dec</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">48</style></volume><pages><style face="normal" font="default" size="100%">806-17</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The increasing accessibility and use of microarrays in transcriptomics has accentuated the need for purpose-designed storage and analysis tools. Here we present UPSC-BASE, a database for analysis and storage of Populus DNA microarray data. A microarray analysis pipeline has also been established to allow consistent and efficient analysis (from small to large scale) of samples in various experimental designs. A range of optimized experimental protocols is provided for each step in generating the data. Within UPSC-BASE, researchers can perform standard and advanced microarray analysis procedures in a user-friendly environment. Background corrections, normalizations, quality-control tools, visualizations, hypothesis tests and export tools are provided without requirements for expert-level knowledge. Although the database has been developed primarily for handling Populus DNA microarrays, most of the tools are generic and can be used for other types of microarray. UPSC-BASE is also a repository of Populus microarray information, providing data from 21 experiments on a total of 407 microarray hybridizations in the public domain of the database. There are also an additional 10 experiments containing 347 hybridizations, where the automatically analysed data are searchable.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17092314?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Pan, Xuejun</style></author><author><style face="normal" font="default" size="100%">Kadla, John F</style></author><author><style face="normal" font="default" size="100%">Ehara, Katsunobu</style></author><author><style face="normal" font="default" size="100%">Gilkes, Neil</style></author><author><style face="normal" font="default" size="100%">Saddler, Jack N</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Organosolv ethanol lignin from hybrid poplar as a radical scavenger: relationship between lignin structure, extraction conditions, and antioxidant activity.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of agricultural and food chemistry</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Agric. Food Chem.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Aug 9</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">54</style></volume><pages><style face="normal" font="default" size="100%">5806-13</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Twenty-one organosolv ethanol lignin samples were prepared from hybrid poplar (Populus nigra xP. maximowiczii) under varied conditions with an experimental matrix designed using response surface methodology (RSM). The lignin preparations were evaluated as potential antioxidants. Results indicated that the lignins with more phenolic hydroxyl groups, less aliphatic hydroxyl groups, low molecular weight, and narrow polydispersity showed high antioxidant activity. Processing conditions affected the functional groups and molecular weight of the extracted organosolv ethanol lignins, and consequently influenced the antioxidant activity of the lignins. In general, the lignins prepared at elevated temperature, longer reaction time, increased catalyst, and diluted ethanol showed high antioxidant activity. Regression models were developed to enable the quantitative prediction of lignin characteristics and antioxidant activity based on the processing conditions.</style></abstract><issue><style face="normal" font="default" size="100%">16</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16881681?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Pan, Xuejun</style></author><author><style face="normal" font="default" size="100%">Gilkes, Neil</style></author><author><style face="normal" font="default" size="100%">Kadla, John</style></author><author><style face="normal" font="default" size="100%">Pye, Kendall</style></author><author><style face="normal" font="default" size="100%">Saka, Shiro</style></author><author><style face="normal" font="default" size="100%">Gregg, David</style></author><author><style face="normal" font="default" size="100%">Ehara, Katsunobu</style></author><author><style face="normal" font="default" size="100%">Xie, Dan</style></author><author><style face="normal" font="default" size="100%">Lam, Dexter</style></author><author><style face="normal" font="default" size="100%">Saddler, Jack</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Bioconversion of hybrid poplar to ethanol and co-products using an organosolv fractionation process: optimization of process yields.</style></title><secondary-title><style face="normal" font="default" size="100%">Biotechnology and bioengineering</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biotechnol. Bioeng.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Aug 5</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">94</style></volume><pages><style face="normal" font="default" size="100%">851-61</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">An organosolv process involving extraction with hot aqueous ethanol has been evaluated for bioconversion of hybrid poplar to ethanol. The process resulted in fractionation of poplar chips into a cellulose-rich solids fraction, an ethanol organosolv lignin (EOL) fraction, and a water-soluble fraction containing hemicellulosic sugars, sugar breakdown products, degraded lignin, and other components. The influence of four independent process variables (temperature, time, catalyst dose, and ethanol concentration) on product yields was analyzed over a broad range using a small composite design and response surface methodology. Center point conditions for the composite design (180 degrees C, 60 min, 1.25% H(2)SO(4), and 60% ethanol), yielded a solids fraction containing approximately 88% of the cellulose present in the untreated poplar. Approximately 82% of the total cellulose in the untreated poplar was recovered as monomeric glucose after hydrolysis of the solids fraction for 24 h using a low enzyme loading (20 filter paper units of cellulase/g cellulose); approximately 85% was recovered after 48 h hydrolysis. Total recovery of xylose (soluble and insoluble) was equivalent to approximately 72% of the xylose present in untreated wood. Approximately 74% of the lignin in untreated wood was recovered as EOL. Other cooking conditions resulted in either similar or inferior product yields although the distribution of components between the various fractions differed markedly. Data analysis generated regression models that describe process responses for any combination of the four variables.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16523526?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Leseberg, Charles H</style></author><author><style face="normal" font="default" size="100%">Li, Aili</style></author><author><style face="normal" font="default" size="100%">Kang, Hui</style></author><author><style face="normal" font="default" size="100%">Duvall, Melvin</style></author><author><style face="normal" font="default" size="100%">Mao, Long</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genome-wide analysis of the MADS-box gene family in Populus trichocarpa.</style></title><secondary-title><style face="normal" font="default" size="100%">Gene</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Gene</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Aug 15</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">378</style></volume><pages><style face="normal" font="default" size="100%">84-94</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Populus trichocarpa (poplar) is distinguished from its herbaceous counterparts Arabidopsis and rice by its woody structure, perennial life cycle, and dioecious, two-whorled flowers. MADS-box genes are known to be involved in many important processes during plant development. Investigation of the poplar genome revealed 105 putative functional MADS-box genes and 12 pseudogenes. These numbers are comparable to those in Arabidopsis. However, poplar has 64 type II MADS-box genes, implying a higher birth rate when compared with Arabidopsis (64 vs.47). In addition to duplications for floral organ identity genes, TM3-like, StMADS11, ANR1 and Bs clades were significantly increased. As indicated by the phylogenetic analysis, there exist at least two MIKC* MADS-box genes in the poplar genome. In contrast, only 41 putative functional type I genes and 9 pseudogenes were found, suggesting that the poplar type I MADS-box genes have experienced a lower rate in both birth and death. Poplar MADS-box genes were distributed on all linkage groups (LGs), except LG XIX. Like other gene families, poplar MADS-box gene family has expanded through tandem gene duplication and segmental duplication events as demonstrated by two genomic regions where clustered MADS-box genes exhibited high similarities in the MADS-box domains. A survey of poplar EST sequences showed that MADS-box genes were expressed in wood and cambium tissues, which are specific to woody plants. The expression of common MADS-box gene in tree-specific tissues suggests that the novel function combinations of a set of genes similar to those in herbaceous plants may account for the development of woody characteristics in poplar.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16831523?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Junghans, U</style></author><author><style face="normal" font="default" size="100%">Polle, A</style></author><author><style face="normal" font="default" size="100%">Düchting, P</style></author><author><style face="normal" font="default" size="100%">Weiler, E</style></author><author><style face="normal" font="default" size="100%">Kuhlman, B</style></author><author><style face="normal" font="default" size="100%">Gruber, F</style></author><author><style face="normal" font="default" size="100%">Teichmann, T</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Adaptation to high salinity in poplar involves changes in xylem anatomy and auxin physiology.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant, cell &amp; environment</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell Environ.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">1519-31</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">To investigate the physiological basis of salt adaptation in poplar, we compared the effect of salt stress on wood anatomy and auxin physiology of the salt-resistant Populus euphratica and salt-sensitive Populus x canescens. Both poplar species showed decreases in vessel lumina associated with increases in wall strength in response to salt, however, in P. euphratica at three-fold higher salt concentrations than in P. x canescens. The predicted hydraulic conductivity of the wood formed under salt stress decreased in P. x canescens, while in P. euphratica, no significant effects of salt on conductivity and transpiration were observed. The concentration of free indole-3-acetic acid (IAA) decreased under salt stress in the xylem of both poplar species, but to a larger extent in P. x canescens than in P. euphratica. Only salt-treated P. euphratica exhibited an increase in IAA-conjugates in the xylem. Genes homologous to the auxin-amidohydrolase ILL3 were isolated from the xylems of P. euphratica and P. x canescens. For functional analysis, the auxin-amidohydrolase from P. x canescens was overexpressed in Arabidopsis. Transgenic Arabidopsis plants were more resistant to salt stress than the wild-type plants. Increased sensitivity of the transgenic Arabidopsis to IAA-Leu showed that the encoded hydrolase used IAA-Leu as a substrate. These results suggest that poplar can use IAA-amidoconjugates in the stem as a source of auxin to balance the effects of salt stress on auxin physiology.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16898015?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ogawa, Yuko</style></author><author><style face="normal" font="default" size="100%">Oku, Hisae</style></author><author><style face="normal" font="default" size="100%">Iwaoka, Emiko</style></author><author><style face="normal" font="default" size="100%">Iinuma, Munekazu</style></author><author><style face="normal" font="default" size="100%">Ishiguro, Kyoko</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Allergy-preventive phenolic glycosides from Populus sieboldii.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of natural products</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Nat. Prod.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">69</style></volume><pages><style face="normal" font="default" size="100%">1215-7</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Allergy-preventive activity was demonstrated for an extract of the bark of Populus sieboldii in a continuing search for allergy-preventive substances from natural sources. By bioassay-directed fractionation of this plant bark, two new phenolic glycosides, siebolside A {2-hydroxy-5-[(benzoyloxy)methyl]phenyl (6'-O-acetyl) beta-D-glucopyranoside} (1) and siebolside B {2-hydroxy-5-[(benzoyloxy)methyl]phenyl beta-D-glucopyranoside} (2), were isolated, together with three known compounds, salicin (3), sakuranin (4), and neosakuranin (5). The structures of 1 and 2 were elucidated by spectroscopic methods. Compounds 1-5 all showed allergy-preventive effects.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16933880?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gehring, Catherine A</style></author><author><style face="normal" font="default" size="100%">Mueller, Rebecca C</style></author><author><style face="normal" font="default" size="100%">Whitham, Thomas G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Environmental and genetic effects on the formation of ectomycorrhizal and arbuscular mycorrhizal associations in cottonwoods.</style></title><secondary-title><style face="normal" font="default" size="100%">Oecologia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Oecologia</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">149</style></volume><pages><style face="normal" font="default" size="100%">158-64</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Although both environment and genetics have been shown to affect the mycorrhizal colonization of host plants, the impacts of these factors on hosts that can be dually colonized by both ectomycorrhizal (EM) and arbuscular mycorrhizal (AM) fungi are less understood. We examined the influence of environment and host crosstype on the EM and AM colonization of cottonwoods (Populus angustifolia and natural hybrids) by comparing levels of colonization of trees growing in common gardens that differed in elevation and soil type. We also conducted a supplemental watering experiment to determine the influence of soil moisture on AM and EM colonization. Three patterns emerged. First, garden location had a significant impact on mycorrhizal colonization, such that EM colonization was 30% higher and AM colonization was 85% lower in the higher elevation garden than the lower elevation garden. Second, crosstype affected total (EM + AM) colonization, but did not affect EM or AM colonization. Similarly, a significant garden x crosstype interaction was found for total colonization, but not for EM or AM colonization. Third, experimental watering resulted in 33% higher EM colonization and 45% lower AM colonization, demonstrating that soil moisture was a major driver of the mycorrhizal differences observed between the gardens. We conclude that environment, particularly soil moisture, has a larger influence on colonization by AM versus EM fungi than host genetics, and suggest that environmental stress may be a major determinant of mycorrhizal colonization in dually colonized host plants.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16642319?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wenes, A-L</style></author><author><style face="normal" font="default" size="100%">Bourguet, D</style></author><author><style face="normal" font="default" size="100%">Andow, D A</style></author><author><style face="normal" font="default" size="100%">Courtin, C</style></author><author><style face="normal" font="default" size="100%">Carré, G</style></author><author><style face="normal" font="default" size="100%">Lorme, P</style></author><author><style face="normal" font="default" size="100%">Sanchez, L</style></author><author><style face="normal" font="default" size="100%">Augustin, S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Frequency and fitness cost of resistance to Bacillus thuringiensis in Chrysomela tremulae (Coleoptera: Chrysomelidae).</style></title><secondary-title><style face="normal" font="default" size="100%">Heredity</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Heredity (Edinb)</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">97</style></volume><pages><style face="normal" font="default" size="100%">127-34</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The &quot;high dose-refuge&quot; (HDR) strategy is commonly recommended and currently used for delaying or preventing pest adaptation to transgenic plants producing Bacillus thuringiensis (Bt) toxins. The efficiency of this strategy depends, among other factors, on the initial frequency of Bt resistance alleles and on the fitness costs associated with these alleles. Two years ago, an allele conferring resistance to Bt poplar was detected in a French population of the poplar pest Chrysomela tremulae F. Although this pest had never been subjected to Bt selection pressure due to human activities, the frequency of this allele was estimated at 0.0037, with a 95% credible (CI) interval of 0.00045-0.0080. We investigated the frequency of this allele in a second sample of C. tremulae collected more than 500 km from the site of the initial population. The estimated frequency in this sample was 0.0113 (95% CI 0.0031-0.0247), reinforcing the conclusion that resistance to Bt plants may be present at detectable frequencies in pest populations before selection resulting from pest management by humans. The frequency of the Bt resistance allele over the two samples was 0.0049 (95% CI 0.0020-0.0091). We also followed five laboratory lines in which the frequency of this allele was initially fixed at 0.500. After five generations maintained on non-Bt poplar leaves, the frequency of this allele decreased in all lines, whereas allelic frequencies at a neutral locus were unaffected. Thus, the Bt resistance allele detected in French populations of C. tremulae is probably associated with a fitness cost.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16705321?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hsu, Chuan-Yu</style></author><author><style face="normal" font="default" size="100%">Liu, Yunxia</style></author><author><style face="normal" font="default" size="100%">Luthe, Dawn S</style></author><author><style face="normal" font="default" size="100%">Yuceer, Cetin</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Poplar FT2 shortens the juvenile phase and promotes seasonal flowering.</style></title><secondary-title><style face="normal" font="default" size="100%">The Plant cell</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Cell</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">18</style></volume><pages><style face="normal" font="default" size="100%">1846-61</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Many woody perennials, such as poplar (Populus deltoides), are not able to form flower buds during the first several years of their life cycle. They must undergo a transition from the juvenile phase to the reproductive phase to be competent to produce flower buds. After this transition, trees begin to form flower buds in the spring of each growing season. The genetic factors that control flower initiation, ending the juvenile phase, are unknown in poplar. The factors that regulate seasonal flower bud formation are also unknown. Here, we report that poplar FLOWERING LOCUS T2 (FT2), a relative of the Arabidopsis thaliana flowering-time gene FT, controls first-time and seasonal flowering in poplar. The FT2 transcript is rare during the juvenile phase of poplar. When juvenile poplar is transformed with FT2 and transcript levels are increased, flowering is induced within 1 year. During the transition between vegetative and reproductive growth in mature trees, FT2 transcripts are abundant during reproductive growth under long days. Subsequently, floral meristems emerge on flanks of the axillary inflorescence shoots. These findings suggest that FT2 is part of the flower initiation pathway in poplar and plays an additional role in regulating seasonal flower initiation that is integrated with the poplar perennial growth habit.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16844908?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Groover, Andrew T</style></author><author><style face="normal" font="default" size="100%">Mansfield, Shawn D</style></author><author><style face="normal" font="default" size="100%">Difazio, Stephen P</style></author><author><style face="normal" font="default" size="100%">Dupper, Gayle</style></author><author><style face="normal" font="default" size="100%">Fontana, Joseph R</style></author><author><style face="normal" font="default" size="100%">Millar, Ryan</style></author><author><style face="normal" font="default" size="100%">Wang, Yvonne</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The Populus homeobox gene ARBORKNOX1 reveals overlapping mechanisms regulating the shoot apical meristem and the vascular cambium.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Mol. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">61</style></volume><pages><style face="normal" font="default" size="100%">917-32</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Secondary growth is supported by a dividing population of meristematic cells within the vascular cambium whose daughter cells are recruited to differentiate within secondary phloem and xylem tissues. We cloned a Populus Class 1 KNOX homeobox gene, ARBORKNOX1 (ARK1), which is orthologous to Arabidopsis SHOOT MERISTEMLESS (STM). ARK1 is expressed in the shoot apical meristem (SAM) and the vascular cambium, and is down-regulated in the terminally differentiated cells of leaves and secondary vascular tissues that are derived from these meristems. Transformation of Populus with either ARK1 or STM over-expression constructs results in similar morphological phenotypes characterized by inhibition of the differentiation of leaves, internode elongation, and secondary vascular cell types in stems. Microarray analysis showed that 41% of genes up-regulated in the stems of ARK1 over-expressing plants encode proteins involved in extracellular matrix synthesis or modification, including proteins involved in cell identity and signaling, cell adhesion, or cell differentiation. These gene expression differences are reflected in alterations of cell wall biochemistry and lignin composition in ARK1 over-expressing plants. Our results suggest that ARK1 has a complex mode of action that may include regulating cell fates through modification of the extracellular matrix. Our findings support the hypothesis that the SAM and vascular cambium are regulated by overlapping genetic programs.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16927204?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ferreira, Sílvia</style></author><author><style face="normal" font="default" size="100%">Hjernø, Karin</style></author><author><style face="normal" font="default" size="100%">Larsen, Martin</style></author><author><style face="normal" font="default" size="100%">Wingsle, Gunnar</style></author><author><style face="normal" font="default" size="100%">Larsen, Peter</style></author><author><style face="normal" font="default" size="100%">Fey, Stephen</style></author><author><style face="normal" font="default" size="100%">Roepstorff, Peter</style></author><author><style face="normal" font="default" size="100%">Salomé Pais, Maria</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Proteome profiling of Populus euphratica Oliv. upon heat stress.</style></title><secondary-title><style face="normal" font="default" size="100%">Annals of botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Ann. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Aug</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">98</style></volume><pages><style face="normal" font="default" size="100%">361-77</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Populus euphratica is a light-demanding species ecologically characterized as a pioneer. It grows in shelter belts along riversides, being part of the natural desert forest ecosystems in China and Middle Eastern countries. It is able to survive extreme temperatures, drought and salt stress, marking itself out as an important plant species to study the mechanisms responsible for survival of woody plants under heat stress.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16740589?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Saura-Valls, Marc</style></author><author><style face="normal" font="default" size="100%">Fauré, Régis</style></author><author><style face="normal" font="default" size="100%">Ragàs, Sergi</style></author><author><style face="normal" font="default" size="100%">Piens, Kathleen</style></author><author><style face="normal" font="default" size="100%">Brumer, Harry</style></author><author><style face="normal" font="default" size="100%">Teeri, Tuula T</style></author><author><style face="normal" font="default" size="100%">Cottaz, Sylvain</style></author><author><style face="normal" font="default" size="100%">Driguez, Hugues</style></author><author><style face="normal" font="default" size="100%">Planas, Antoni</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Kinetic analysis using low-molecular mass xyloglucan oligosaccharides defines the catalytic mechanism of a Populus xyloglucan endotransglycosylase.</style></title><secondary-title><style face="normal" font="default" size="100%">The Biochemical journal</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Biochem. J.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Apr 1</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">395</style></volume><pages><style face="normal" font="default" size="100%">99-106</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Plant XETs [XG (xyloglucan) endotransglycosylases] catalyse the transglycosylation from a XG donor to a XG or low-molecular-mass XG fragment as the acceptor, and are thought to be important enzymes in the formation and remodelling of the cellulose-XG three-dimensional network in the primary plant cell wall. Current methods to assay XET activity use the XG polysaccharide as the donor substrate, and present limitations for kinetic and mechanistic studies of XET action due to the polymeric and polydisperse nature of the substrate. A novel activity assay based on HPCE (high performance capillary electrophoresis), in conjunction with a defined low-molecular-mass XGO {XG oligosaccharide; (XXXGXXXG, where G=Glcbeta1,4- and X=[Xylalpha1,6]Glcbeta1,4-)} as the glycosyl donor and a heptasaccharide derivatized with ANTS [8-aminonaphthalene-1,3,6-trisulphonic acid; (XXXG-ANTS)] as the acceptor substrate was developed and validated. The recombinant enzyme PttXET16A from Populus tremula x tremuloides (hybrid aspen) was characterized using the donor/acceptor pair indicated above, for which preparative scale syntheses have been optimized. The low-molecular-mass donor underwent a single transglycosylation reaction to the acceptor substrate under initial-rate conditions, with a pH optimum at 5.0 and maximal activity between 30 and 40 degrees C. Kinetic data are best explained by a ping-pong bi-bi mechanism with substrate inhibition by both donor and acceptor. This is the first assay for XETs using a donor substrate other than polymeric XG, enabling quantitative kinetic analysis of different XGO donors for specificity, and subsite mapping studies of XET enzymes.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16356166?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gierlinger, Notburga</style></author><author><style face="normal" font="default" size="100%">Schwanninger, Manfred</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Chemical imaging of poplar wood cell walls by confocal Raman microscopy.</style></title><secondary-title><style face="normal" font="default" size="100%">Plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">140</style></volume><pages><style face="normal" font="default" size="100%">1246-54</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Confocal Raman microscopy was used to illustrate changes of molecular composition in secondary plant cell wall tissues of poplar (Populus nigra x Populus deltoids) wood. Two-dimensional spectral maps were acquired and chemical images calculated by integrating the intensity of characteristic spectral bands. This enabled direct visualization of the spatial variation of the lignin content without any chemical treatment or staining of the cell wall. A small (0.5 microm) lignified border toward the lumen was observed in the gelatinous layer of poplar tension wood. The variable orientation of the cellulose was also characterized, leading to visualization of the S1 layer with dimensions smaller than 0.5 mum. Scanning Raman microscopy was thus shown to be a powerful, nondestructive tool for imaging changes in molecular cell wall organization with high spatial resolution.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16489138?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Poland, Therese M</style></author><author><style face="normal" font="default" size="100%">Haack, Robert A</style></author><author><style face="normal" font="default" size="100%">Petrice, Toby R</style></author><author><style face="normal" font="default" size="100%">Miller, Deborah L</style></author><author><style face="normal" font="default" size="100%">Bauer, Leah S</style></author><author><style face="normal" font="default" size="100%">Gao, Ruitong</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Field evaluations of systemic insecticides for control of Anoplophora glabripennis (Coleoptera: Cerambycidae) in China.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of economic entomology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Econ. Entomol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">99</style></volume><pages><style face="normal" font="default" size="100%">383-92</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae), a pest native to China and Korea, was discovered in North America in 1996. Currently, the only reliable strategy available for eradication and control is to cut and chip all infested trees. We evaluated various doses of the systemic insecticides azadirachtin, emamectin benzoate, imidacloprid, and thiacloprid for control of A. glabripennis in naturally infested elms (Ulmus spp.), poplars (Populus spp.), and willows (Salix spp. ) in China between 2000 and 2002. Significantly more dead A. glabripennis adults were found beneath elm and poplar trees treated with imidacloprid (in 2000 and 2001) or thiacloprid (in 2001) and beneath willow trees injected with imidacloprid or thiacloprid (in 2002) compared with control trees. In 2000, 4 mo after injection, the density of live A. glabripennis was significantly reduced in poplar trees treated with imidacloprid (90%) and in willow trees treated with imidacloprid (83%) or emamectin benzoate (71%) compared with controls. In 2001, 9 mo after injection, the density of live A. glabripennis was significantly reduced in poplar (76%) and willow (45%) trees treated with imidacloprid compared with control trees. Similarly, percentage mortality of all life stages of A. glabripennis feeding within trees was significantly higher on poplar trees 4 mo after injection with imidacloprid (64%) in 2000 and on elms (55%) and poplars (63%) 9 mo after injection with imidacloprid in 2001 compared with control trees. Imidacloprid residue levels in leaves and twigs collected at various times from 1 d to 9 mo after injection ranged from 0.27 to 0.46 ppm. Injecting A. glabripennis-infested trees with imidacloprid can result in significant mortality of adults during maturation feeding on leaves and twigs and of all life stages feeding within infested trees. Imidacloprid is translocated rapidly in infested trees and is persistent at lethal levels for several months. Although, injection with imidacloprid does not provide complete control of A. glabripennis, systemic insecticides may prove useful as part of an integrated eradication or management program.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16686136?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Bangert, R K</style></author><author><style face="normal" font="default" size="100%">Turek, R J</style></author><author><style face="normal" font="default" size="100%">Rehill, B</style></author><author><style face="normal" font="default" size="100%">Wimp, G M</style></author><author><style face="normal" font="default" size="100%">Schweitzer, J A</style></author><author><style face="normal" font="default" size="100%">Allan, G J</style></author><author><style face="normal" font="default" size="100%">Bailey, J K</style></author><author><style face="normal" font="default" size="100%">Martinsen, G D</style></author><author><style face="normal" font="default" size="100%">Keim, P</style></author><author><style face="normal" font="default" size="100%">Lindroth, R L</style></author><author><style face="normal" font="default" size="100%">Whitham, T G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A genetic similarity rule determines arthropod community structure.</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Ecol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">15</style></volume><pages><style face="normal" font="default" size="100%">1379-91</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We define a genetic similarity rule that predicts how genetic variation in a dominant plant affects the structure of an arthropod community. This rule applies to hybridizing cottonwood species where plant genetic variation determines plant-animal interactions and structures a dependent community of leaf-modifying arthropods. Because the associated arthropod community is expected to respond to important plant traits, we also tested whether plant chemical composition is one potential intermediate link between plant genes and arthropod community composition. Two lines of evidence support our genetic similarity rule. First, in a common garden experiment we found that trees with similar genetic compositions had similar chemical compositions and similar arthropod compositions. Second, in a wild population, we found a similar relationship between genetic similarity in cottonwoods and the dependent arthropod community. Field data demonstrate that the relationship between genes and arthropods was also significant when the hybrids were analysed alone, i.e. the pattern is not dependent upon the inclusion of both parental species. Because plant-animal interactions and natural hybridization are common to diverse plant taxa, we suggest that a genetic similarity rule is potentially applicable, and may be extended, to other systems and ecological processes. For example, plants with similar genetic compositions may exhibit similar litter decomposition rates. A corollary to this genetic similarity rule predicts that in systems with low plant genetic variability, the environment will be a stronger factor structuring the dependent community. Our findings argue that the genetic composition of a dominant plant can structure higher order ecological processes, thus placing community and ecosystem ecology within a genetic and evolutionary framework. A genetic similarity rule also has important conservation implications because the loss of genetic diversity in one species, especially dominant or keystone species that define many communities, may cascade to negatively affect the rest of the dependent community.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16626460?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ralph, Steven</style></author><author><style face="normal" font="default" size="100%">Oddy, Claire</style></author><author><style face="normal" font="default" size="100%">Cooper, Dawn</style></author><author><style face="normal" font="default" size="100%">Yueh, Hesther</style></author><author><style face="normal" font="default" size="100%">Jancsik, Sharon</style></author><author><style face="normal" font="default" size="100%">Kolosova, Natalia</style></author><author><style face="normal" font="default" size="100%">Philippe, Ryan N</style></author><author><style face="normal" font="default" size="100%">Aeschliman, Dana</style></author><author><style face="normal" font="default" size="100%">White, Rick</style></author><author><style face="normal" font="default" size="100%">Huber, Dezene</style></author><author><style face="normal" font="default" size="100%">Ritland, Carol E</style></author><author><style face="normal" font="default" size="100%">Benoit, François</style></author><author><style face="normal" font="default" size="100%">Rigby, Tracey</style></author><author><style face="normal" font="default" size="100%">Nantel, André</style></author><author><style face="normal" font="default" size="100%">Butterfield, Yaron S N</style></author><author><style face="normal" font="default" size="100%">Kirkpatrick, Robert</style></author><author><style face="normal" font="default" size="100%">Chun, Elizabeth</style></author><author><style face="normal" font="default" size="100%">Liu, Jerry</style></author><author><style face="normal" font="default" size="100%">Palmquist, Diana</style></author><author><style face="normal" font="default" size="100%">Wynhoven, Brian</style></author><author><style face="normal" font="default" size="100%">Stott, Jeffrey</style></author><author><style face="normal" font="default" size="100%">Yang, George</style></author><author><style face="normal" font="default" size="100%">Barber, Sarah</style></author><author><style face="normal" font="default" size="100%">Holt, Robert A</style></author><author><style face="normal" font="default" size="100%">Siddiqui, Asim</style></author><author><style face="normal" font="default" size="100%">Jones, Steven J M</style></author><author><style face="normal" font="default" size="100%">Marra, Marco A</style></author><author><style face="normal" font="default" size="100%">Ellis, Brian E</style></author><author><style face="normal" font="default" size="100%">Douglas, Carl J</style></author><author><style face="normal" font="default" size="100%">Ritland, Kermit</style></author><author><style face="normal" font="default" size="100%">Bohlmann, Jörg</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genomics of hybrid poplar (Populus trichocarpax deltoides) interacting with forest tent caterpillars (Malacosoma disstria): normalized and full-length cDNA libraries, expressed sequence tags, and a cDNA microarray for the study of insect-induced defences </style></title><secondary-title><style face="normal" font="default" size="100%">Molecular ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Ecol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">15</style></volume><pages><style face="normal" font="default" size="100%">1275-97</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">As part of a genomics strategy to characterize inducible defences against insect herbivory in poplar, we developed a comprehensive suite of functional genomics resources including cDNA libraries, expressed sequence tags (ESTs) and a cDNA microarray platform. These resources are designed to complement the existing poplar genome sequence and poplar (Populus spp.) ESTs by focusing on herbivore- and elicitor-treated tissues and incorporating normalization methods to capture rare transcripts. From a set of 15 standard, normalized or full-length cDNA libraries, we generated 139,007 3'- or 5'-end sequenced ESTs, representing more than one-third of the c. 385,000 publicly available Populus ESTs. Clustering and assembly of 107,519 3'-end ESTs resulted in 14,451 contigs and 20,560 singletons, altogether representing 35,011 putative unique transcripts, or potentially more than three-quarters of the predicted c. 45,000 genes in the poplar genome. Using this EST resource, we developed a cDNA microarray containing 15,496 unique genes, which was utilized to monitor gene expression in poplar leaves in response to herbivory by forest tent caterpillars (Malacosoma disstria). After 24 h of feeding, 1191 genes were classified as up-regulated, compared to only 537 down-regulated. Functional classification of this induced gene set revealed genes with roles in plant defence (e.g. endochitinases, Kunitz protease inhibitors), octadecanoid and ethylene signalling (e.g. lipoxygenase, allene oxide synthase, 1-aminocyclopropane-1-carboxylate oxidase), transport (e.g. ABC proteins, calreticulin), secondary metabolism [e.g. polyphenol oxidase, isoflavone reductase, (-)-germacrene D synthase] and transcriptional regulation [e.g. leucine-rich repeat transmembrane kinase, several transcription factor classes (zinc finger C3H type, AP2/EREBP, WRKY, bHLH)]. This study provides the first genome-scale approach to characterize insect-induced defences in a woody perennial providing a solid platform for functional investigation of plant-insect interactions in poplar.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16626454?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ye, Zheng-Hua</style></author><author><style face="normal" font="default" size="100%">York, William S</style></author><author><style face="normal" font="default" size="100%">Darvill, Alan G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Important new players in secondary wall synthesis.</style></title><secondary-title><style face="normal" font="default" size="100%">Trends in plant science</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Trends Plant Sci.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">11</style></volume><pages><style face="normal" font="default" size="100%">162-4</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Secondary walls in wood are the most abundant biomass produced by plants. Understanding how plants make wood is not only of interest in basic plant biology but also has important implications for tree biotechnology. Three recent papers report exciting findings regarding a group of novel glycosyltransferases (GTs) involved in secondary wall synthesis. Because little is known about genes involved in the synthesis of wood polysaccharides other than cellulose, the identification of these GTs is a breakthrough in the molecular dissection of wood formation.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16537114?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Cline, Morris G</style></author><author><style face="normal" font="default" size="100%">Thangavelu, Mirunalni</style></author><author><style face="normal" font="default" size="100%">Dong-Il, Kim</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">A possible role of cytokinin in mediating long-distance nitrogen signaling in the promotion of sylleptic branching in hybrid poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of plant physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Plant Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">163</style></volume><pages><style face="normal" font="default" size="100%">684-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Nitrogen fertilization of roots enhances shoot growth in plants and cytokinins are known to initiate bud outgrowth in shoots. Is it possible that root-derived cytokinins may play a role in long-distance signaling for nitrogen availability in the promotion of sylleptic branching in hybrid poplar? Nitrogen fertilization in the form of 5 mM NH4NO3, KNO3 or NH4Cl was applied to roots of three hybrid poplar clones exhibiting contrasting degrees of sylleptic branching. Cytokinin (0.1-1 mM benzyladenine, BA) was applied directly to lateral buds of shoots. Glutamate, asparagine and glutamine were also applied as drops to buds or as foliar sprays. NH4NO3, KNO3 and NH4Cl all usually enhanced sylleptic branching within a week in the high sylleptic clone (11-11) but in four out of five trials there was no effect in the low sylleptic clone (47-174). NH4NO3 added directly to buds had no effect. Also, glutamate, asparagine and glutamine had no effect. However, 1 mM BA promoted lateral bud outgrowth in all three clones. These results are consistent with the long-distance nitrogen signaling hypothesis of Forde and Sakakibara wherein nitrogen is transduced to cytokinin via enhanced ipt activity in the roots and is translocated up the shoot with the subsequent promotion of leaf/bud outgrowth.</style></abstract><issue><style face="normal" font="default" size="100%">6</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16546001?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lipson, David A</style></author><author><style face="normal" font="default" size="100%">Blair, Michelle</style></author><author><style face="normal" font="default" size="100%">Barron-Gafford, Greg</style></author><author><style face="normal" font="default" size="100%">Grieve, Kathrine</style></author><author><style face="normal" font="default" size="100%">Murthy, Ramesh</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Relationships between microbial community structure and soil processes under elevated atmospheric carbon dioxide.</style></title><secondary-title><style face="normal" font="default" size="100%">Microbial ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Microb. Ecol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">51</style></volume><pages><style face="normal" font="default" size="100%">302-14</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">There is little current understanding of the relationship between soil microbial community composition and soil processes rates, nor of the effect climate change and elevated CO(2) will have on microbial communities and their functioning. Using the eastern cottonwood (Populus deltoides) plantation at the Biosphere 2 Laboratory, we studied the relationships between microbial community structure and process rates, and the effects of elevated atmospheric CO(2) on microbial biomass, activity, and community structure. Soils were sampled from three treatments (400, 800, and 1200 ppm CO(2)), a variety of microbial biomass and activity parameters were measured, and the bacterial community was described by 16S rRNA libraries. Glucose substrate-induced respiration (SIR) was significantly higher in the 1200 ppm CO(2) treatment. There were also a variety of complex, nonlinear responses to elevated CO(2). There was no consistent effect of elevated CO(2) on bacterial diversity; however, there was extensive variation in microbial community structure within the plantation. The southern ends of the 800 and 1200 ppm CO(2) bays were dominated by beta-Proteobacteria, and had higher fungal biomass, whereas the other areas contained more alpha-Proteobacteria and Acidobacteria. A number of soil process rates, including salicylate, glutamate, and glycine substrate-induced respiration and proteolysis, were significantly related to the relative abundance of the three most frequent bacterial taxa, and to fungal biomass. Overall, variation in microbial activity was better explained by microbial community composition than by CO(2) treatment. However, the altered diversity and activity in the southern bays of the two high CO(2) treatments could indicate an interaction between CO(2) and light.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16598634?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Wei, Hao</style></author><author><style face="normal" font="default" size="100%">Meilan, Richard</style></author><author><style face="normal" font="default" size="100%">Brunner, Amy M</style></author><author><style face="normal" font="default" size="100%">Skinner, Jeffrey S</style></author><author><style face="normal" font="default" size="100%">Ma, Caiping</style></author><author><style face="normal" font="default" size="100%">Strauss, Steven H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Transgenic sterility in Populus: expression properties of the poplar PTLF, Agrobacterium NOS and two minimal 35S promoters in vegetative tissues.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">26</style></volume><pages><style face="normal" font="default" size="100%">401-10</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Transgenic sterility is a desirable trait for containment of many kinds of transgenes and exotic species. Genetically engineered floral sterility can be imparted by expression of a cytotoxin under the control of a predominantly floral-tissue-specific promoter. However, many otherwise desirable floral promoters impart substantial non-floral expression, which can impair plant health or make it impossible to regenerate transgenic plants. We are therefore developing a floral sterility system that is capable of attenuating undesired background vegetative expression. As a first step towards this goal, we compared the vegetative expression properties of the promoter of the poplar (Populus trichocarpa Torr. &amp; Gray) homolog of the floral homeotic gene LEAFY (PTLF), which could be used to impart male and female flower sterility, to that of three candidate attenuator-gene promoters: the cauliflower mosaic virus (CaMV) 35S basal promoter, the CaMV 35S basal promoter fused to the TMV omega element and the nopaline synthase (NOS) promoter. The promoters were evaluated via promoter::GUS gene fusions in a transgenic poplar hybrid (Populus tremula L. x P. alba L.) by both histochemical and fluorometric GUS assays. In leaves, the NOS promoter conveyed the highest activity and had a mean expression level 5-fold higher than PTLF, whereas the CaMV 35S basal promoter fused to the omega element and the CaMV 35S basal promoter alone directed mean expression levels that were 0.5x and 0.35x that of PTLF, respectively. Differential expression in shoots, leaves, stems and roots was observed only for the NOS and PTLF promoters. Strongest expression was observed in roots for the NOS promoter, whereas the PTLF promoter directed highest expression in shoots. The NOS promoter appears best suited to counteract vegetative expression of a cytotoxin driven by the PTLF promoter where 1:1 toxin:attenuator expression is required.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16414919?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Millard, Peter</style></author><author><style face="normal" font="default" size="100%">Wendler, Renate</style></author><author><style face="normal" font="default" size="100%">Grassi, Giacomo</style></author><author><style face="normal" font="default" size="100%">Grelet, Gwen-Aelle</style></author><author><style face="normal" font="default" size="100%">Tagliavini, Massimo</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Translocation of nitrogen in the xylem of field-grown cherry and poplar trees during remobilization.</style></title><secondary-title><style face="normal" font="default" size="100%">Tree physiology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Tree Physiol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">26</style></volume><pages><style face="normal" font="default" size="100%">527-36</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Studies of small trees growing in pots have established that individual amino acids or amides are translocated in the xylem sap of a range of tree species following bud burst, as a consequence of nitrogen (N) remobilization from storage. This paper reports the first study of N translocation in the xylem of large, deciduous, field-grown trees during N remobilization in the spring. We applied 15N fertilizer to the soil around 10-year-old Prunus avium L. and Populus trichocharpa Torr. &amp; Gray ex Hook var. Hastata (Dode) A. Henry x Populus balsamifera L. var. Michauxii (Dode) Farwell trees before bud burst to label N taken up by the roots. Recovery of unlabeled N in xylem sap and leaves was used to demonstrate that P. avium remobilizes N in both glutamine (Gln) and asparagine (Asn). Sap concentrations of both amides rose sharply after bud burst, peaking 14 days after bud burst for Gln, and remaining high some 45 days for Asn. There was no 15N enrichment of either amide until 21 days after bud burst. In the Populus trees, nearly all the N was translocated in the sap as Gln, the concentration of which peaked and then declined before the amide was enriched with 15N, 40 days after bud burst. Xylem sap of clonal P. avium trees was sampled at different positions in the crown to assess if the amino acid and amide composition of the sap varied within the crown. Sap was sampled during remobilization (when the concentration of Gln was maximal), at the end of remobilization and at the end of the experiment (68 days after bud burst). Although the date of sampling had a highly significant effect on sap composition, the effect of position of sampling was marginal. The results are discussed in relation to N translocation in adult trees and the possibility of measuring N remobilization by calculating the flux of N translocation in the xylem.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16414931?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Gilchrist, Erin J</style></author><author><style face="normal" font="default" size="100%">Haughn, George W</style></author><author><style face="normal" font="default" size="100%">Ying, Cheng C</style></author><author><style face="normal" font="default" size="100%">Otto, Sarah P</style></author><author><style face="normal" font="default" size="100%">Zhuang, Jun</style></author><author><style face="normal" font="default" size="100%">Cheung, Dorothy</style></author><author><style face="normal" font="default" size="100%">Hamberger, Björn</style></author><author><style face="normal" font="default" size="100%">Aboutorabi, Fariba</style></author><author><style face="normal" font="default" size="100%">Kalynyak, Tatyana</style></author><author><style face="normal" font="default" size="100%">Johnson, Lee</style></author><author><style face="normal" font="default" size="100%">Bohlmann, Joerg</style></author><author><style face="normal" font="default" size="100%">Ellis, Brian E</style></author><author><style face="normal" font="default" size="100%">Douglas, Carl J</style></author><author><style face="normal" font="default" size="100%">Cronk, Quentin C B</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Use of Ecotilling as an efficient SNP discovery tool to survey genetic variation in wild populations of Populus trichocarpa.</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular ecology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mol. Ecol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">15</style></volume><pages><style face="normal" font="default" size="100%">1367-78</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Abstract Ecotilling was used as a simple nucleotide polymorphism (SNP) discovery tool to examine DNA variation in natural populations of the western black cottonwood, Populus trichocarpa, and was found to be more efficient than sequencing for large-scale studies of genetic variation in this tree. A publicly available, live reference collection of P. trichocarpa from the University of British Columbia Botanical Garden was used in this study to survey variation in nine different genes among individuals from 41 different populations. A large amount of genetic variation was detected, but the level of variation appears to be less than in the related species, Populus tremula, based on reported statistics for that tree. Genes examined varied considerably in their level of variation, from PoptrTB1 which had a single SNP, to PoptrLFY which had more than 23 in the 1000-bp region examined. Overall nucleotide diversity, measured as (Total), was relatively low at 0.00184. Linkage disequilibrium, on the other hand, was higher than reported for some woody plant species, with mean r2 equal to 0.34. This study reveals the potential of Ecotilling as a rapid genotype discovery method to explore and utilize the large pool of genetic variation in tree species.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16626459?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Liu, Gui-Feng</style></author><author><style face="normal" font="default" size="100%">Cheng, Gui-Lan</style></author><author><style face="normal" font="default" size="100%">Jiang, Jing</style></author><author><style face="normal" font="default" size="100%">Bai, Shuang</style></author><author><style face="normal" font="default" size="100%">Yu, Ying</style></author><author><style face="normal" font="default" size="100%">Cai, Zhi-Jun</style></author><author><style face="normal" font="default" size="100%">Dong, Jing-Xiang</style></author><author><style face="normal" font="default" size="100%">Li, Shu-Juan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">[The transformation of betA gene into the pollen plantlets of Populus simonii x P. nigra].</style></title><secondary-title><style face="normal" font="default" size="100%">Zhi wu sheng li yu fen zi sheng wu xue xue bao = Journal of plant physiology and molecular biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Zhi Wu Sheng Li Yu Fen Zi Sheng Wu Xue Xue Bao</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006 Apr</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">32</style></volume><pages><style face="normal" font="default" size="100%">163-8</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In this study, betA gene was introduced into the pollen plantlets of Populus simonii x P. nigra using Agrobacterium-mediated transformation. The four kanamycine-resistant plants obtained were identified as transgenic plants by PCR detection and the results were all positive. The result of quantitative real-time PCR detection showed that the betA gene was transcribed and expressed in all the transformed plants, but the transcript levels are different. Test of salt-tolerance of the transgenic plants showed that 80%-00% of transgenic plants were rooted while 0 of non-transgenic plants were rooted at 0.55% NaCl stress, and 0 of transgenic plants were rooted at 0.70%-0.80% NaCl stress. The betaine content analysis showed the betaine content of the transgenic plants are obviously higher than that in non-transgenic plants, so transformation betA gene raised the salt tolerance to the transgenic plants.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16622314?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Beauchamp, Vanessa B</style></author><author><style face="normal" font="default" size="100%">Stromberg, Juliet C</style></author><author><style face="normal" font="default" size="100%">Stutz, Jean C</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Arbuscular mycorrhizal fungi associated with Populus-Salix stands in a semiarid riparian ecosystem.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">170</style></volume><pages><style face="normal" font="default" size="100%">369-80</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">This study examined the activity, species richness, and species composition of the arbuscular mycorrhizal fungal (AMF) community of Populus-Salix stands on the Verde River (Arizona, USA), quantified patterns of AMF richness and colonization along complex floodplain gradients, and identified environmental variables responsible for structuring the AMF community. Samples from 61 Populus-Salix stands were analyzed for AMF and herbaceous composition, AMF colonization, gravimetric soil moisture, soil texture, per cent organic matter, pH, and concentrations of nitrate, bicarbonate phosphorus and exchangeable potassium. AMF species richness declined with stand age and distance from and elevation above the channel and was positively related to perennial species cover and richness and gravimetric soil moisture. Distance from and elevation above the active channel, forest age, annual species cover, perennial species richness, and exchangeable potassium concentration all played a role in structuring the AMF community in this riparian area. Most AMF species were found across a wide range of soil conditions, but a subset of species tended to occur more often in hydric areas. This group of riparian affiliate AMF species includes several not previously encountered in the surrounding Sonoran desert.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16608461?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Donaldson, Jack R</style></author><author><style face="normal" font="default" size="100%">Kruger, Eric L</style></author><author><style face="normal" font="default" size="100%">Lindroth, Richard L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Competition- and resource-mediated tradeoffs between growth and defensive chemistry in trembling aspen (Populus tremuloides).</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">169</style></volume><pages><style face="normal" font="default" size="100%">561-70</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Costs of defense are thought to maintain genetic variations in the expression of defense within plant populations. As with many plant species, aspen exhibits considerable variation in allocation to secondary metabolites. This study examined the independent and interactive effects of genotype, soil fertility and belowground competition on defensive chemistry and growth in trembling aspen (Populus tremuloides). Four aspen genotypes were grown with high and low soil fertility, and with and without root competition. Physiological, morphological and allocational determinants of growth were measured to identify growth-defense tradeoffs. Nutrient limitation and competition decreased growth, leaf mass ratio, leaf nitrogen concentration and photosynthesis, and increased root : shoot ratio and leaf condensed tannin concentrations. The competition treatment also resulted in increased leaf phenolic glycoside (PG) concentrations. Aspen growth was negatively correlated with PG concentrations under low fertility with competition. The relationship between growth and its major determinants was also negatively related to foliar condensed tannins expressed as a proportion of tree mass, indicating an additional indirect cost of allocation to secondary metabolites.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16411958?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ko, Jae-Heung</style></author><author><style face="normal" font="default" size="100%">Prassinos, Constantinos</style></author><author><style face="normal" font="default" size="100%">Han, Kyung-Hwan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Developmental and seasonal expression of PtaHB1, a Populus gene encoding a class III HD-Zip protein, is closely associated with secondary growth and inversely correlated with the level of microRNA (miR166).</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">169</style></volume><pages><style face="normal" font="default" size="100%">469-78</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In contrast to our knowledge of the shoot apical meristem, our understanding of cambium meristem differentiation and maintenance is limited. Class III homeodomain leucine-zipper (HD-Zip) proteins have been shown to play a regulatory role in vascular differentiation. The hybrid aspen (Populus tremulaxPopulus alba) class III HD-Zip transcription factor (PtaHB1) and microRNA 166 (Pta-miR166) family were cloned from hybrid aspen using a combination of in silico and polymerase chain reaction methods. Expression analyses of PtaHB1 and Pta-miR166 were performed by Northern blot analysis. The expression of PtaHB1 was closely associated with wood formation and regulated both developmentally and seasonally, with the highest expression during the active growing season. Also, its expression was inversely correlated with the level of Pta-miR166. Pta-miR166-directed cleavage of PtaHB1 in vivo was confirmed using modified 5'-rapid amplification of cDNA ends (RACE). The expression of Pta-miR166 was much higher in the winter than in the growing seasons, suggesting seasonal and developmental regulation of microRNA in this perennial plant species.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16411950?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Choi, Catherine</style></author><author><style face="normal" font="default" size="100%">Liu, Zhenlan</style></author><author><style face="normal" font="default" size="100%">Adams, Keith L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Evolutionary transfers of mitochondrial genes to the nucleus in the Populus lineage and coexpression of nuclear and mitochondrial Sdh4 genes.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">172</style></volume><pages><style face="normal" font="default" size="100%">429-39</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The transfer of mitochondrial genes to the nucleus is an ongoing evolutionary process in flowering plants. Evolutionarily recent gene transfers provide insights into the evolutionary dynamics of the process and the way in which transferred genes become functional in the nucleus. Genes that are present in the mitochondrion of some angiosperms but have been transferred to the nucleus in the Populus lineage were identified by searches of Populus sequence databases. Sequence analyses and expression experiments were used to characterize the transferred genes. Two succinate dehydrogenase genes and six mitochondrial ribosomal protein genes have been transferred to the nucleus in the Populus lineage and have become expressed. Three transferred genes have gained an N-terminal mitochondrial targeting presequence from other pre-existing genes and two of the transferred genes do not contain an N-terminal targeting presequence. Intact copies of the succinate dehydrogenase gene Sdh4 are present in both the mitochondrion and the nucleus. Both copies of Sdh4 are expressed in multiple organs of two Populus species and RNA editing occurs in the mitochondrial copy. These results provide a genome-wide perspective on mitochondrial genes that were transferred to the nucleus and became expressed, functional genes during the evolutionary history of Populus.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17083674?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rouhier, Nicolas</style></author><author><style face="normal" font="default" size="100%">Couturier, Jérémy</style></author><author><style face="normal" font="default" size="100%">Jacquot, Jean-Pierre</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genome-wide analysis of plant glutaredoxin systems.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of experimental botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Exp. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">57</style></volume><pages><style face="normal" font="default" size="100%">1685-96</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The recent release of the first tree genome (Populus trichocarpa) has allowed a comparison to be made of the multigenic glutaredoxin (Grx) and glutathione reductase (GR) families of this tree with those of other sequenced organisms and especially of the two other fully sequenced plant species, Arabidopsis thaliana and Oryza sativa. Grxs are small proteins involved in disulphide bridge or protein-glutathione adduct reduction, and they are maintained in a reduced form using glutathione and an NADPH-dependent GR. While the P. trichocarpa and O. sativa genomes are nearly five times larger than that of A. thaliana, they contain approximately 45 000 and 37 500 genes compared with the 25 500 genes of A. thaliana. On the one hand, the GR gene composition varies little between species and the gene structures are relatively conserved. On the other hand, the Grx gene family can be divided into three subgroups and the gene content is larger in P. trichocarpa (36 genes) compared with A. thaliana and O. sativa (31 and 27 genes, respectively). This could be partly explained by the occurrence of more duplication events, and this is especially true for one of the three identified Grx subgroups (subgroup III). The expression of most of these genes was confirmed by analysing expressed sequence tags present in various databases. In addition, the expression of Grx of subgroups I and II was examined by RT-PCR in various poplar organs. A complete classification based essentially on gene structure and sequence identity is proposed.</style></abstract><issue><style face="normal" font="default" size="100%">8</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16720602?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Tsai, Chung-Jui</style></author><author><style face="normal" font="default" size="100%">Harding, Scott A</style></author><author><style face="normal" font="default" size="100%">Tschaplinski, Timothy J</style></author><author><style face="normal" font="default" size="100%">Lindroth, Richard L</style></author><author><style face="normal" font="default" size="100%">Yuan, Yinan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Genome-wide analysis of the structural genes regulating defense phenylpropanoid metabolism in Populus.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">172</style></volume><pages><style face="normal" font="default" size="100%">47-62</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Salicin-based phenolic glycosides, hydroxycinnamate derivatives and flavonoid-derived condensed tannins comprise up to one-third of Populus leaf dry mass. Genes regulating the abundance and chemical diversity of these substances have not been comprehensively analysed in tree species exhibiting this metabolically demanding level of phenolic metabolism. Here, shikimate-phenylpropanoid pathway genes thought to give rise to these phenolic products were annotated from the Populus genome, their expression assessed by semiquantitative or quantitative reverse transcription polymerase chain reaction (PCR), and metabolic evidence for function presented. Unlike Arabidopsis, Populus leaves accumulate an array of hydroxycinnamoyl-quinate esters, which is consistent with broadened function of the expanded hydroxycinnamoyl-CoA transferase gene family. Greater flavonoid pathway diversity is also represented, and flavonoid gene families are larger. Consistent with expanded pathway function, most of these genes were upregulated during wound-stimulated condensed tannin synthesis in leaves. The suite of Populus genes regulating phenylpropanoid product accumulation should have important application in managing phenolic carbon pools in relation to climate change and global carbon cycling.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16945088?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lang, Christina</style></author><author><style face="normal" font="default" size="100%">Schulze, Jutta</style></author><author><style face="normal" font="default" size="100%">Mendel, Ralf-R</style></author><author><style face="normal" font="default" size="100%">Hänsch, Robert</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">HaloTag: a new versatile reporter gene system in plant cells.</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of experimental botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Exp. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">57</style></volume><pages><style face="normal" font="default" size="100%">2985-92</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">HaloTag Interchangeable Labeling Technology (HaloTag) was originally developed for mammalian cell analysis. In this report, the use of HaloTag is demonstrated in plant cells for the first time. This system allows different fluorescent colours to be used to visualize the localization of the non-fluorescent HaloTag protein within living cells. A vector was constructed which expresses the HaloTag protein under the control of the 35S promoter of cauliflower mosaic virus. The functionality of the HaloTag construct was tested in transient assays by (i) transforming tobacco protoplasts and (ii) using biolistic transformation of intact leaf cells of tobacco and poplar plants. Two to fourteen days after transformation, the plant material was incubated with ligands specific for labelling the HaloTag protein, and fluorescence was visualized by confocal laser scanning microscopy. The results demonstrate that HaloTag technology is a flexible system which generates efficient fluorescence in different types of plant cells. The ligand-specific labelling of HaloTag protein was not hampered by the plant cell wall.</style></abstract><issue><style face="normal" font="default" size="100%">12</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16873446?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Liphadzi, S</style></author><author><style face="normal" font="default" size="100%">Kirkham, M B</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Heavy metal displacement in EDTA-assisted phytoremediation of biosolids soil.</style></title><secondary-title><style face="normal" font="default" size="100%">Water science and technology : a journal of the International Association on Water Pollution Research</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Water Sci. Technol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">54</style></volume><pages><style face="normal" font="default" size="100%">147-53</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Chelating agents are added to soil to solubilise the metals for enhanced phytoextraction. Yet no studies follow the displacement and leaching of heavy metals in soil with biosolids following solubilisation with chelates. The objective of this work was to determine the mobility of heavy metals in biosolids in a soil from a sludge farm that had received biosolids for 25 years. The soil was placed in columns in a greenhouse. Columns either had a plant (poplar) or no plant. After the poplar seedlings had grown for 144 d, the tetrasodium salt of the chelating agent EDTA was irrigated onto the surface of the soil at a rate of 1 g per kg of soil. Drainage water was analysed for three toxic heavy metals and four essential heavy metals. Without EDTA, concentrations of the seven heavy metals in the leachate from columns with or without plants were low or below detection limits. With or without plants, the EDTA mobilised all heavy metals and increased their concentration in drainage water. Without plants, the concentrations of Cd, Cu, Fe, and Zn in the leachate from columns with EDTA were above drinking-water standards. The presence of poplar plants in the soil reduced the concentrations of Cu, Fe, and Zn in the leachate so it fell within drinking-water standards. Concentrations of Cd and Pb in the leachate remained above drinking-water standards with or without plants.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17087380?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Vandepoele, Klaas</style></author><author><style face="normal" font="default" size="100%">Casneuf, Tineke</style></author><author><style face="normal" font="default" size="100%">Van de Peer, Yves</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Identification of novel regulatory modules in dicotyledonous plants using expression data and comparative genomics.</style></title><secondary-title><style face="normal" font="default" size="100%">Genome biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Genome Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">7</style></volume><pages><style face="normal" font="default" size="100%">R103</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Transcriptional regulation plays an important role in the control of many biological processes. Transcription factor binding sites (TFBSs) are the functional elements that determine transcriptional activity and are organized into separable cis-regulatory modules, each defining the cooperation of several transcription factors required for a specific spatio-temporal expression pattern. Consequently, the discovery of novel TFBSs in promoter sequences is an important step to improve our understanding of gene regulation.</style></abstract><issue><style face="normal" font="default" size="100%">11</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17090307?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Monclus, Romain</style></author><author><style face="normal" font="default" size="100%">Dreyer, Erwin</style></author><author><style face="normal" font="default" size="100%">Villar, Marc</style></author><author><style face="normal" font="default" size="100%">Delmotte, Francis M</style></author><author><style face="normal" font="default" size="100%">Delay, Didier</style></author><author><style face="normal" font="default" size="100%">Petit, Jean-Michel</style></author><author><style face="normal" font="default" size="100%">Barbaroux, Cécile</style></author><author><style face="normal" font="default" size="100%">Le Thiec, Didier</style></author><author><style face="normal" font="default" size="100%">Bréchet, Claude</style></author><author><style face="normal" font="default" size="100%">Brignolas, Franck</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Impact of drought on productivity and water use efficiency in 29 genotypes of Populus deltoides x Populus nigra.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">169</style></volume><pages><style face="normal" font="default" size="100%">765-77</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We examined the relationships among productivity, water use efficiency (WUE) and drought tolerance in 29 genotypes of Populus x euramericana (Populus deltoides x Populus nigra), and investigated whether some leaf traits could be used as predictors for productivity, WUE and drought tolerance. At Orléans, France, drought was induced on one field plot by withholding water, while a second plot remained irrigated and was used as a control. Recorded variables included stem traits (e.g. biomass) and leaf structural (e.g. leaf area) and functional traits [e.g. intrinsic water use efficiency (Wi) and carbon isotope discrimination (Delta)]. Productivity and Delta displayed large genotypic variability and were not correlated. Delta scaled negatively with Wi and positively with stomatal conductance under moderate drought, suggesting that the diversity for Delta was mainly driven by stomatal conductance. Most of the productive genotypes displayed a low level of drought tolerance (i.e. a large reduction of biomass), while the less productive genotypes presented a large range of drought tolerance. The ability to increase WUE in response to water deficit was necessary but not sufficient to explain the genotypic diversity of drought tolerance.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16441757?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Yoon, Jong Moon</style></author><author><style face="normal" font="default" size="100%">Van Aken, Benoit</style></author><author><style face="normal" font="default" size="100%">Schnoor, Jerald L</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Leaching of contaminated leaves following uptake and phytoremediation of RDX, HMX, and TNT by poplar.</style></title><secondary-title><style face="normal" font="default" size="100%">International journal of phytoremediation</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Int J Phytoremediation</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">8</style></volume><pages><style face="normal" font="default" size="100%">81-94</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The uptake and fate of 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) by hybrid poplars in hydroponic systems were compared and exposed leaves were leached with water to simulate potential exposure pathways from groundwater in the field. TNT was removed from solution more quickly than nitramine explosives. Most of radioactivity remained in root tissues for 14C-TNT, but in leaves for 14C-RDX and 14C-HMX. Radiolabel recovery for TNT and HMX was over 94%, but that of RDX decreased over time, suggesting a loss of volatile products. A considerable fraction (45.5%) of radioactivity taken up by whole plants exposed to 14C-HMX was released into deionized water, mostly as parent compound after 5 d of leaching. About a quarter (24.0%) and 1.2% were leached for RDX and TNT, respectively, mostly as transformed products. Leached radioactivity from roots was insignificant in all cases (&lt; 2%). This is the first report in which small amounts of transformation products of RDX leach from dried leaves following uptake by poplars. Such behavior for HMX was reported earlier and is reconfirmed here. All three compounds differ substantially in their fate and transport during the leaching process.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16615309?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Nicole, Marie-Claude</style></author><author><style face="normal" font="default" size="100%">Hamel, Louis-Philippe</style></author><author><style face="normal" font="default" size="100%">Morency, Marie-Josée</style></author><author><style face="normal" font="default" size="100%">Beaudoin, Nathalie</style></author><author><style face="normal" font="default" size="100%">Ellis, Brian E</style></author><author><style face="normal" font="default" size="100%">Séguin, Armand</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">MAP-ping genomic organization and organ-specific expression profiles of poplar MAP kinases and MAP kinase kinases.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC genomics</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Genomics</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">7</style></volume><pages><style face="normal" font="default" size="100%">223</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">As in other eukaryotes, plant mitogen-activated protein kinase (MAPK) cascades are composed of three classes of hierarchically organized protein kinases, namely MAPKKKs, MAPKKs, and MAPKs. These modules rapidly amplify and transduce extracellular signals into various appropriate intracellular responses. While extensive work has been conducted on the post-translational regulation of specific MAPKKs and MAPKs in various plant species, there has been no systematic investigation of the genomic organization and transcriptional regulation of these genes.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16945144?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Major, Ian T</style></author><author><style face="normal" font="default" size="100%">Constabel, C Peter</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Molecular analysis of poplar defense against herbivory: comparison of wound- and insect elicitor-induced gene expression.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title><alt-title><style face="normal" font="default" size="100%">New Phytol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">172</style></volume><pages><style face="normal" font="default" size="100%">617-35</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In order to characterize defense responses of hybrid poplar (Populus trichocarpax P. deltoides), we profiled leaf transcript patterns elicited by wounding and by regurgitant from forest tent caterpillar (FTC; Malacosoma disstria), a Lepidopteran defoliator of poplars. Macroarrays were used to compare transcript profiles. Both FTC-regurgitant (FTC-R) and mechanical wounding with pliers elicited expression of a variety of genes, and for these genes our analysis indicated that these treatments induced qualitatively similar responses. Similarly, a comparison of responses of directly treated and systemically induced leaves indicated extensive overlap in the sets of induced genes. FTC-R was found to contain the insect-derived elicitor volicitin. The simulated herbivory treatments resulted in the induction of genes involved in poplar defense and secondary metabolism. We also identified wound-responsive genes with roles in primary metabolism, including a putative invertase, lipase, and acyl-activating enzyme; some of these genes may have roles in defense signaling. In addition, we found three unknown genes containing a ZIM motif which may represent novel transcription factors.</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17096789?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Meilan, Richard</style></author><author><style face="normal" font="default" size="100%">Ma, Caiping</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Poplar (Populus spp.).</style></title><secondary-title><style face="normal" font="default" size="100%">Methods in molecular biology (Clifton, N.J.)</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Methods Mol. Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">344</style></volume><pages><style face="normal" font="default" size="100%">143-51</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Although species within the genus Populus are, in general, easier to transform and regenerate in vitro than most other trees, many poplar species are very recalcitrant. Many protocols that previously have been reported were developed for a specific genotype or species. Thus, it has often been necessary to re-optimize a protocol each time research is initiated with a new genotype. The method presented in this chapter has been effective for a wide variety of poplar genotypes.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17033059?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">García-Lorenzo, Maribel</style></author><author><style face="normal" font="default" size="100%">Sjödin, Andreas</style></author><author><style face="normal" font="default" size="100%">Jansson, Stefan</style></author><author><style face="normal" font="default" size="100%">Funk, Christiane</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Protease gene families in Populus and Arabidopsis.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC plant biology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">BMC Plant Biol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">6</style></volume><pages><style face="normal" font="default" size="100%">30</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Proteases play key roles in plants, maintaining strict protein quality control and degrading specific sets of proteins in response to diverse environmental and developmental stimuli. Similarities and differences between the proteases expressed in different species may give valuable insights into their physiological roles and evolution.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17181860?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ferrieri, Abigail P</style></author><author><style face="normal" font="default" size="100%">Thorpe, Michael R</style></author><author><style face="normal" font="default" size="100%">Ferrieri, Richard A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Stimulating natural defenses in poplar clones (OP-367) increases plant metabolism of carbon tetrachloride.</style></title><secondary-title><style face="normal" font="default" size="100%">International journal of phytoremediation</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Int J Phytoremediation</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">8</style></volume><pages><style face="normal" font="default" size="100%">233-43</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Groundwater contamination by carbon tetrachloride (CCl4) presents a health risk as a potential carcinogen and pollutant that is capable of depleting the ozone layer. Although use of poplar trees in a phytoremediation capacity has proven to be cost effective for cleaning contaminated sites, minimizing leaf emission of volatile contaminants remains a pressing issue. We hypothesized that recently fixed carbon plays a key role in CCl4 metabolism in planta yielding nonvolatile trichloroacetic acid (TCA) and that the extent of this metabolism can be altered by heightening plant defenses. Labeling intact leaves with (11)CO2 (t 1/2 20.4 m) can test this hypothesis, because the extremely short half-life of the tracer reflects only those processes involving recently fixed carbon. Using radio-HPLC analysis, we observed [(11)C]TCA from leaf extract from poplar clones (OP-367) whose roots were exposed to a saturated solution of CCl4 (520 ppm). Autoradiography of [(11)C]photosynthate showed increased leaf export and partitioning to the apex within 24 h of CCl4 exposure, suggesting that changes in plant metabolism and partitioning of recently fixed carbon occur rapidly. Additionally, leaf CCl4 emissions were highest in the morning, when carbon pools are low, suggesting a link between contaminant metabolism and leaf carbon utilization. Further, treatment with methyljasmonate, a plant hormone implicated in defense signal transduction, reduced leaf CCl4 emissions two-fold due to the increased formation of TCA.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/17120527?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Miyazawa, Shin-Ichi</style></author><author><style face="normal" font="default" size="100%">Livingston, Nigel J</style></author><author><style face="normal" font="default" size="100%">Turpin, David H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Stomatal development in new leaves is related to the stomatal conductance of mature leaves in poplar (Populus trichocarpaxP. deltoides).</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of experimental botany</style></secondary-title><alt-title><style face="normal" font="default" size="100%">J. Exp. Bot.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">57</style></volume><pages><style face="normal" font="default" size="100%">373-80</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In general, stomatal density (SD) decreases when plants are grown at high CO2 concentrations. Recent studies suggest that signals produced from mature leaves regulate the SD of expanding leaves. To determine the underlying driver of these signals in poplar (Populus trichocarpaxP. deltoides) saplings, a cuvette system was used whereby the environment around mature (lower) leaves could be controlled independently of that around developing (upper) leaves. A series of experiments were performed in which the CO2 concentration, vapour pressure deficit (D), and irradiance (Q) around the lower leaves were varied while the (ambient) conditions around the upper leaves were unchanged. The overall objective was to break the nexus between leaf stomatal conductance and transpiration and photosynthesis rates of lower leaves and determine which, if any, of these parameters regulate stomatal development in the upper expanding leaves. SD, stomatal index (SI), and epidermal cell density (ED) were measured on the adaxial and abaxial surfaces of fully expanded upper leaves. SD and SI decreased with increasing lower leaf CO2 concentration (150-780 ppm) at both ambient (1.3-1.6 kPa) and low (0.7-1.0 kPa) D. SD and SI at low D were generally higher than at ambient D. By contrast, ED was relatively insensitive to both vapour pressure and CO2 concentration. When lower leaves were shaded, upper leaf SD, SI, and ED decreased but did not change with varying CO2 concentration. These results suggest that epidermal cell development and stomatal development are regulated by different physiological mechanisms. SI of the upper leaves was positively and highly correlated (r2&gt;0.84) with the stomatal conductance of the lower leaves independent of their net photosynthesis and transpiration rates, suggesting that the stomatal conductance of mature leaves has a regulatory effect on the stomatal development of expanding leaves.</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16172139?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Oliva, J M</style></author><author><style face="normal" font="default" size="100%">Manzanares, P</style></author><author><style face="normal" font="default" size="100%">Ballesteros, I</style></author><author><style face="normal" font="default" size="100%">Negro, M J</style></author><author><style face="normal" font="default" size="100%">González, A</style></author><author><style face="normal" font="default" size="100%">Ballesteros, M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Application of Fenton's reaction to steam explosion prehydrolysates from poplar biomass.</style></title><secondary-title><style face="normal" font="default" size="100%">Applied biochemistry and biotechnology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Appl. Biochem. Biotechnol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2005</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2005 Spring</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">121-124</style></volume><pages><style face="normal" font="default" size="100%">887-99</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The application of Fenton's reaction to enhance the fermentability of prehydrolysates obtained from steam explosion pretreatment of poplar biomass was studied. Reaction conditions of temperature and H2O2 and Fe(II) concentrations were studied. The fermentability of prehydrolysate treated by Fenton's reaction was tested by using different inoculum sizes of thermotolerant strain Kluyveromyces marxianus CECT 10875. The highest percentages of toxic compound degradation (ranging from 71 to 93% removal) were obtained at the highest H2O2 concentration tested (50 mM). However, a negative effect on fermentability was observed at this H2O2 concentration at the lower inoculum loading. An increase in inoculum size to 0.6 g/L resulted in an enhanced ethanol fermentation yield of 95% relative to control.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/15930568?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Chung, Yun-Chin</style></author><author><style face="normal" font="default" size="100%">Bakalinsky, Alan</style></author><author><style face="normal" font="default" size="100%">Penner, Michael H</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Enzymatic saccharification and fermentation of xylose-optimized dilute acid-treated lignocellulosics.</style></title><secondary-title><style face="normal" font="default" size="100%">Applied biochemistry and biotechnology</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Appl. Biochem. Biotechnol.</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2005</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2005 Spring</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">121-124</style></volume><pages><style face="normal" font="default" size="100%">947-61</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The cellulose reactivity of two lignocellulosic feedstocks, switchgrass and poplar, was evaluated under straight saccharification (SS) and simultaneous saccharification and fermentation (SSF) conditions following dilute sulfuric acid pretreatments designed for optimum xylose yields. The optimum pretreatment conditions, within the constraints of the experimental system (Parr batch reactor), were 1.2% acid, 180 degrees C, and 0.5 min for switchgrass and 1% acid, 180 degrees C, and 0.56 min for poplar. The cellulase enzyme preparation was from Trichoderma reesei and fermentations were done with Saccharomyces cerevisiae. Time courses for SS were monitored as the sum of glucose and cellobiose; those for SSF as the sum of glucose, cellobiose, and ethanol. Percentage conversions under SS conditions were 79.1% and 91.4% for the pretreated poplar and switchgrass feedstocks, respectively. Analogous values under SSF conditions were 73.0% and 90.3% for pretreated poplar and switchgrass, respectively.</style></abstract><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/15930573?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Johnson, Jason A</style></author><author><style face="normal" font="default" size="100%">Harrington, Thomas C</style></author><author><style face="normal" font="default" size="100%">Engelbrecht, C J B</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Phylogeny and taxonomy of the North American clade of the Ceratocystis fimbriata complex.</style></title><secondary-title><style face="normal" font="default" size="100%">Mycologia</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Mycologia</style></alt-title></titles><dates><year><style  face="normal" font="default" size="100%">2005</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2005 Sep-Oct</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">97</style></volume><pages><style face="normal" font="default" size="100%">1067-92</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Ceratocystis fimbriata is a widely distributed, plant pathogenic fungus that causes wilts and cankers on many woody hosts. Earlier phylogenetic analyses of DNA sequences revealed three geographic clades within the C. fimbriata complex that are centered respectively in North America, Latin America and Asia. This study looked for cryptic species within the North American clade. The internal transcribed spacer regions (ITS) of the rDNA were sequenced, and phylogenetic analysis indicated that most isolates from the North American clade group into four host-associated lineages, referred to as the aspen, hickory, oak and cherry lineages, which were isolated primarily from wounds or diseased trees of Populus, Carya, Quercus and Prunus, respectively. A single isolate collected from P. serotina in Wisconsin had a unique ITS sequence. Allozyme electromorphs also were highly polymorphic within the North American clade, and the inferred phylogenies from these data were congruent with the ITS-rDNA analyses. In pairing experiments isolates from the aspen, hickory, oak and cherry lineages were interfertile only with other isolates from their respective lineages. Inoculation experiments with isolates of the four host-associated groupings showed strong host specialization by isolates from the aspen and hickory lineages on Populus tremuloides and Carya illinoensis, respectively, but isolates from the oak and cherry lineages did not consistently reveal host specialization. Morphological features distinguish isolates in the North American clade from those of the Latin American clade (including C. fimbriata sensu stricto). Based on the phylogenetic evidence, interfertility, host specialization and morphology, the oak and cherry lineages are recognized as the earlier described C. variospora, the poplar lineage as C. populicola sp. nov., and the hickory lineage as C. caryae sp. nov. A new species associated with the bark beetle Scolytus quadrispinosus on Carya is closely related to C. caryae and is described as C. smalleyi.</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom1><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16596958?dopt=Abstract</style></custom1></record><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Cseke, Leland J</style></author><author><style face="normal" font="default" size="100%">Cseke, Sarah Beth</style></author><author><style face="normal" font="default" size="100%">Ravinder, Namritha</style></author><author><style face="normal" font="default" size="100%">Taylor, Lorelei C</style></author><author><style face="normal" font="default" size="100%">Shankar, Anupama</style></author><author><style face="normal" font="default" size="100%">Sen, Banalata</style></author><author><style face="normal" font="default" size="100%">Thakur, Ramesh</style></author><author><style face="normal" font="default" size="100%">Karnosky, David F</style></author><author><style face="normal" font="default" size="100%">Podila, Gopi K</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">SEP-class genes in Populus tremuloides and their likely role in reproductive survival of poplar trees.</style></title><secondary-title><style face="normal" font="default" size="100%">Gene</style></secondary-title><alt-title><style face="normal" font="default" size="100%">Gene</style></alt-title></titles><d
