tailieunhanh - Báo cáo khoa học: "Differentiation of xylem cells in rolC transgenic aspen trees – a study of secondary cell wall development"

Tuyển tập các báo cáo nghiên cứu về lâm nghiệp được đăng trên tạp chí lâm nghiệp quốc tế đề tài: Differentiation of xylem cells in rolC transgenic aspen trees – a study of secondary cell wall development. | 679 Ann. For. Sci. 59 2002 679-685 INRA EDP Sciences 2002 DOI forest 2002056 Original article Differentiation of xylem cells in rolC transgenic aspen trees - a study of secondary cell wall development Claudia Grunwalda Katia Ruelb and Uwe Schmittc Institute for Wood Biology University of Hamburg Leuschnerstr. 91 21031 Hamburg Germany b Centre de Recherches sur les Macromolecules Végétales CERMAV -CNRS BP 53 38041 Grenoble Cedex 9 France c Institute for Wood Biology and Wood Protection Federal Research Centre for Forestry and Forest Products Leuschnerstr. 91 21031 Hamburg Germany Received 16 August 2001 accepted 21 January 2002 Abstract - Xylem cell differentiation of 35S-rolC transgenic aspen was analyzed and compared with wild type trees. The transgenic trees mainly characterized by dwarfism and physiological alterations did not show distinctive differences in the structure and chemical composition of xylem cell walls as compared with the wild type trees. However there was a difference in the dynamics of differentiation. In the transgenics the formation of xylem cells was delayed and the differentiation zone reduced to a few rows. PATAg and KMnO4 staining in electron microscopy as well as UV-microspectrophotometry revealed that in the transgenics during secondary wall formation polysaccharides and lignin were simultaneously deposited close to the cambium. Immunocytochemical techniques have visualized the first deposition of condensed lignin in cell corners and of non-condensed lignin in secondary walls near cell corners. Because of altered formation and differentiation of xylem cells 35S-rolC transgenic aspen may be useful to study factors controlling the differentiation continuum. Populus I rolC wood formation lignification electron microscopy immunogoldlabelling UV-microspectrophotometry Résumé - Differenciation des cellules du xylème chez le peuplier transgénique 35S-rolC - une étude de la formation des parois secondai-res. La differenciation des .