Changes in levels of cell wall constituents in wheat seedlings grown under continuous hypergravity conditions
Changes in levels of cell wall constituents in wheat seedlings grown under continuous hypergravity conditions
复制标题
DOI：
10.1016/j.asr.2005.02.066
复制
发表时间：
2005-01-01
期刊：
影响因子：
--
通讯作者：
Hoson, T
中科院分区：
文献类型：
--
作者：
Wakabayashi, K;Soga, K;Hoson, T
研究了连续超重力刺激对小麦幼苗细胞壁组分数量和组成的影响。超重力（300 g）处理3 d后，半纤维素、纤维素等细胞壁多糖的净含量增加，但伸长量降低。结果表明，超重力条件下每单位长度枝条的细胞壁多糖含量增加。半纤维素馏分中含有多糖的中，低分子量范围（5 kDa-1 MDa），并增加响应超重力。此外，阿拉伯糖（Ara）和木糖（Xyl），半纤维素部分的主要糖组分的量，在超重力条件下增加。除了壁多糖，超重力增加细胞壁结合的酚酸，如阿魏酸（FA）和二阿魏酸（DFA）的量。此外，苯丙氨酸解氨酶（PAL，EC 4.3.1.5）的活性在超重力条件下增强。这些结果表明，持续的超重力刺激合成的细胞壁成分，特别是半纤维素阿拉伯聚糖和细胞壁结合的FA和DFA在小麦芽。PAL活性的增加可能促进了FA和DFA的形成。细胞壁结构的这些变化可能涉及在超重力条件下形成刚性和坚韧的细胞壁，从而有助于植物抵抗重力刺激维持其结构的能力。(c)2005年空间研委会。由爱思唯尔有限公司出版。保留所有权利。
Effects of continuous hypergravity stimuli on the amounts and composition of cell wall constituents were investigated in wheat shoots. Hypergravity (300 g) treatment for three days after germination increased the net amount of cell wall polysaccharides such as hemicellulose and cellulose, but reduced the shoot elongation. As a result, the amount of cell wall polysaccharides per unit length of shoot increased under hypergravity. The hemicellulose fraction contained polysaccharides in the middle and low molecular mass range (5 kDa-1 MDa) and increased in response to hypergravity. Also, the amounts of arabinose (Ara) and xylose (Xyl), the major sugar components of the hemicellulose fraction, increased under hypergravity conditions. In addition to wall polysaccharides, hypergravity increased the amounts of cell wall-bound phenolic acids, such as ferulic acid (FA) and diferulic acid (DFA). Furthermore, the activity of phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) was enhanced under hypergravity conditions. These results suggest that continuous hypergravity stimulates the synthesis of cell wall constituents, especially hemicellulosic arabinoxylans and cell wall-bound FA and DFA in wheat shoots. The increased PAL activity may promote the formation of FA and DFA. These changes in cell wall architecture may be involved in making rigid and tough cell walls under hypergravity conditions and thereby contribute to the ability of plant to sustain their structures against gravitational stimuli. (c) 2005 COSPAR. Published by Elsevier Ltd. All rights reserved.