| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
|
First published online January 13, 2006; 10.1104/pp.105.072652 Plant Physiology 140:946-962 (2006) © 2006 American Society of Plant Biologists Poplar Carbohydrate-Active Enzymes. Gene Identification and Expression Analyses1,[W]Department of Forest Genetics and Plant Physiology, Umeå Plant Science Center, SE–90183 Umea, Sweden (J.G.-L., N.N., J.T., S.A.-G., B. Sundberg, E.J.M.); Department of Plant Physiology, Umeå Plant Science Center, SE–90187 Umea, Sweden (M.G., B. Segerman, S.K., L.A.K.); Architecture et Fonction des Macromolécules Biologiques, Unité Mixte de Recherche 6098, Centre National de la Recherche Scientifique, Universités Aix-Marseille I and II, 13288 Marseille cedex 9, France (P.M.C., B.H.); Royal Institute of Technology, School of Biotechnology, AlbaNova University Center, SE–10691 Stockholm, Sweden (H.A., S.D., E.M., T.T.T.); and Department of Botany, Stockholm University, 10691 Stockholm, Sweden (S.K.)
Over 1,600 genes encoding carbohydrate-active enzymes (CAZymes) in the Populus trichocarpa (Torr. & 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.
1 This work was supported by grants from the European Commission (to B.H.), Formas (to E.J.M. and B.S.), the Swedish Research Council (L.A.K.), the Wallenberg Foundation, European project Eden (QLK5–CT–2001–00443), the Wood Ultrastructure Research Centre, and the Umeå Plant Science Center Excellence Centre. 2 These authors contributed equally to the paper. 3 Present address: Department of Biology, University of Western Ontario, London, Ontario, Canada N6A 5B7. 4 Present address: Institute of Physical and Chemical Research, Plant Science Center, 1–7–22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230–0045, Japan. 5 Present address: Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, WB420C, Toronto, Canada M5S 3E5. The author responsible for distribution of materials integral to the findings presented in this article in accordance with the policy described in the Instructions for Authors (www.plantphysiol.org) is: Ewa J. Mellerowicz (ewa.mellerowicz{at}genfys.slu.se). [W] The online version of this article contains Web-only data. Article, publication date, and citation information can be found at www.plantphysiol.org/cgi/doi/10.1104/pp.105.072652. * Corresponding author; e-mail ewa.mellerowicz{at}genfys.slu.se; fax 46–90–786–8165. Received October 7, 2005; returned for revision December 21, 2005; accepted December 21, 2005. This article has been cited by other articles:
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| ASPB Publications | PLANT PHYSIOLOGY® | THE PLANT CELL | |
|---|---|---|---|
