Biogenesis and Conversion of Wood Substance

高等植物木质部的木质化细胞壁由木质物质组成。这项合作研究包括对木材物质的生物发生和其转化利用的研究，19名调查人员分为5个小组。木质部分化和细胞壁木质化的分子研究：在分子水平上对分离的单细胞木质部分化进行了研究，木质素的生物发生及其表达调控基因的研究取得了显著进展。细胞壁结构与细胞壁组分生物发生的关系：在超微结构水平上研究了纤维素微原纤维、基质多糖和木质素的形成和沉积。对细胞壁的木质化过程也进行了生化模拟。木材细胞壁的功能及其形成的物理关系：分析了针叶树和阔叶树的生长应力与木材细胞壁成熟的关系。木质素的可变性和不均匀性：研究了木质素不均匀性的各种原因。木材物质的化学、物理和生物可转化性：报告了化学转化的一个例子和物理转化的一种方法。阐明了木材的生物降解机理。将出版一份包括所有研究工作摘要的报告（日文）。

Wood substance makes lignified cell walls in xylem in higher plants. This co-operative research comprizes studies on biogenesis of wood substance to those on its conversions for use, and 19 investigators were grouped into 5 teams.1. Molecular aspects of xylem differentiation and lignification of cell wall : Xylem differentiation of isolated single cells were studied at molecular level, and studies on genes concerning biogenesis of lignin and on control of its expression were remarkably developed.2. Architecture of cell wall in relation to biogenesis of wall components : Formation and depositions of cellulose microfibrils, matrix polysaccharides and lignins were studied at ultrastructure levels. The process of lignification in the cell wall was also simulated biochemically.3. Function and physics of wood cellwall in relation to its formation : Generation of growth stresses in tree stems were analized in relation to the maturation of wood cell walls in needle- and broard-leaved trees.4. Variability and inhomogeneity of lignin : Various causes of inhomogeneity of lignin were investigated.5. Chemical, physical and biological convertibility of wood substance : An example of chemical conversion and a method of physical conversion were reported. The biological degradation mechanism of wood was clarified.A report which comprises summaries of all research works will be published (in Japanese).