WATANABE Akira University of Tokyo Professor, 大学院・理学系, 教授 (70023471)
MATOU Tohro Kyoto University Associate Professor, 農学部, 助教授 (50157393)
MIMURA Toshiu Hitotubashi University Associate Professor, 商学部, 助教授 (20174120)
SATOU Shinobu Tukuba University Associate Professor, 生物科学, 助教授 (70196236)
WADA Masamistu Tokyo Metropolitan University Professor, 理学部, 教授 (60011681)
|Budget Amount *help
¥15,200,000 (Direct Cost: ¥15,200,000)
Fiscal Year 1996: ¥5,500,000 (Direct Cost: ¥5,500,000)
Fiscal Year 1995: ¥9,700,000 (Direct Cost: ¥9,700,000)
The following results were obtained ;
(1) Five glucanases bound to barley cell walls were identified as,  endo-1,3 ; 1,4-glucanase,  endo-1,3-glucanase-1,  endo-1,3-glucanase-2,  exoglucanase-1, and  exoglucanase-2. The enzymes involved in 1,3 ; 1,4-glucan degradation in the cereal plants are  and .
(2) The enzymic activity that converts indoleacetaldehyde to indole-3-acetic acid was found in barley cell walls. The Km was 5muM which is lower than that for the cytoplasmic enzyme with similar activity (31muM). Apoplast of dark grown squash hypocotyls containes the concentration of indole-3-acetic acid 5 times higher than the symplast.
(3) Essential element, boron, which was known to be localized at cell walls, was bound to rhamnogalacturoans by a diol-ester linkage and cross-linked two polysaccharides.
(4) It was suggested that when xyloglucan was breakdown during elongation growth, xyloglucans becomes susceptible to enzyme action after cellulose molecules into which zyloglucan was inserted, was degraded by endoglucanase activity.
(5) In is unlikely that plant has RGD peptide homologs similar to those found on animal cells.
The technique with pH dependent fluorescence dye revealed that the phosphate lever of vacuoles were homeostatically regulted by the cooperative action of mechanism wiht which the cytoplasmic phosphate level was regulated.
These results clearly demonstrate that the apoplast is the site where substances prerequisite for the plant life, such as plant hormones, polysaccharide-related enzymes, or inorganic ions, are dynamically metabolized.