一种植物细胞壁松驰蛋白:膨胀素

A Kind of Plant Cell Wall Expansion Protein-Expansin

在植物细胞的生长过程中 ,多糖和蛋白质分泌到细胞壁里层 ,并形成具有一定机械强度的网络 ,这个网络是能伸展的 ,除非细胞停止生长。在细胞的生长过程中 ,一种细胞壁蛋白—膨胀素首次被鉴定出来具有使细胞壁的多糖网络疏松的能力 ,从而使膨压驱动的细胞扩大。膨胀素由两个多基因家族即α -膨胀素和 β -膨胀素多基因家族编码 ,每种基因的表达具有部位和细胞类型的特异性 ,但最新的研究也表明拟南芥中的膨胀素可以分为三个亚家族。越来越多的膨胀素基因从各种植物中鉴定出来 ,系统分析显示它们可能从一个共同的祖先基因进化而来。膨胀素的作用机理研究的还不是很清楚 ,但因为它们具有特别的功能 ,因此展现出良好的工业化应用前景。

Ploysaccharides and proteins are secreted to the inner surface of the growing cell wall,where they assemble into a network that is mechanically strong, yet remains extensive until the cells cease growth.During cell growth,a cell wall protein-expansin was first identified for unlocking the network of polysaccharides, permitting tugor-driven cell enlargement.Expansins are encoded by two multigene families, which are α-expansin and β-expansin multigene families, and each is often expressed in high specific locations and cell types, but latest research also showed that expansins in Arabidopsis can be classified into three subfamilies. More and more expansin genes are identified from all kinds of plant, and phylogenetic analysis suggests that they may evolve from a common ancestral gene.The mechanism of the action of expansins still remains unclear, but based on their specific function, they exhibit a good prospect of application in industry.