期刊
MOLECULAR PLANT
卷 2, 期 5, 页码 893-903出版社
CELL PRESS
DOI: 10.1093/mp/ssp054
关键词
G-layer; tensile stress; xyloglucan; xyloglucan endotransglucosylase
资金
- Program for the Promotion of Basic Research Activities for Innovative Biosciences (PROBRAIN)
- Japan Society for the Promotion of Science
- KAKENHI [17380108, 19208016, 19580188, 19405030]
- Global Center of Excellence Program [E-04]
- Grants-in-Aid for Scientific Research [17380108, 19405030, 19580188] Funding Source: KAKEN
In response to environmental variation, angiosperm trees bend their stems by forming tension wood, which consists of a cellulose-rich G (gelatinous)-layer in the walls of fiber cells and generates abnormal tensile stress in the secondary xylem. We produced transgenic poplar plants overexpressing several endoglycanases to reduce each specific polysaccharide in the cell wall, as the secondary xylem consists of primary and secondary wall layers. When placed horizontally, the basal regions of stems of transgenic poplars overexpressing xyloglucanase alone could not bend upward due to low strain in the tension side of the xylem. In the wild-type plants, xyloglucan was found in the inner surface of G-layers during multiple layering. In situ xyloglucan endotransglucosylase (XET) activity showed that the incorporation of whole xyloglucan, potentially for wall tightening, began at the inner surface layers S1 and S2 and was retained throughout G-layer development, while the incorporation of xyloglucan heptasaccharide (XXXG) for wall loosening occurred in the primary wall of the expanding zone. We propose that the xyloglucan network is reinforced by XET to form a further connection between wall-bound and secreted xyloglucans in order to withstand the tensile stress created within the cellulose G-layer microfibrils.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据