Division of roles among members of the XTH gene family in plants
Division of roles among members of the XTH gene family in plants
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DOI：
10.1080/11263500500055924
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发表时间：
2005-03-01
期刊：
影响因子：
2
通讯作者：
Nishitani, K
中科院分区：
文献类型：
--
作者：
Nishitani, K
木葡聚糖内切转葡糖基酶/水解酶（XTH）基因家族编码负责木葡聚糖的水解和/或分子接枝的一类酶，并且被认为对于植物细胞壁的纤维素木葡聚糖框架的构建和重构是必需的。个别XTH基因转录本在植物中，特别是在拟南芥和水稻中的表达分析表明，该基因家族的大多数成员表现出不同的器官特异性和激素信号的反应方面的表达谱。进一步的表达分析，使用转基因植物携带各种XTH启动子：：GUS融合基因已披露严格和特定的细胞类型依赖的表达模式内各自的器官。这意味着该基因家族的每个成员在特定发育阶段的特定组织中分别负责由特定信号集调节的特定过程。通过将该基因表达模型应用于细胞壁动力学所需的其他基因家族，提出了细胞壁类型特异性酶组假说。这一假说表明，单个细胞壁类型是由一组蛋白质的协同作用形成和维持的，这些蛋白质由参与细胞壁形成的几十个基因家族中的选定成员组成。这一假说还认为，有一个主基因定义细胞壁类型，从而在一组蛋白质中引导单个酶，以构建某种类型的细胞壁。
The xyloglucan endotransglucosylase/hydrolase (XTH) gene family encodes a class of enzymes responsible for the hydrolysis and/or molecular grafting of xyloglucan, and is considered essential for the construction and restructuring of the cellulose xyloglucan framework of plant cell walls. Expression analyses of individual XTH gene transcripts in plants, particularly in Arabidopsis and rice, show that most members of this gene family exhibit distinct expression profiles in terms of organ specificity and responses to hormonal signals. Further expression analyses using transgenic plants carrying various XTH promoter::GUS fusion genes have disclosed strict and specific cell-type-dependent expression patterns within respective organs. This implies that each member of this gene family is individually responsible for a specific process regulated by a specific set of signals in a specific tissue at a specific stage of development. By applying this gene expression model to other gene families required for cell wall dynamics, a cell wall-type specific enzyme-set hypothesis has been proposed. This hypothesis suggests that individual cell wall-types are formed and maintained by the concerted action of sets of proteins that consist of selected members from several dozen gene families that are involved in the formation of cell walls. This hypothesis also holds that there is a master gene(s) that defines cell wall-type, and thereby conducts individual enzymes, within a set of proteins, to construct a certain type of cell wall.