植物脱落酸信号转导途径的上游信使  

Upstream Messengers of Abscisic Acid Signaling Pathway in Plant

作　　者：陶怡[1] 王盈阁 李鸿杰[1] 李晚忱[1] 付凤玲[1] 

机构地区：[1]四川农业大学玉米研究所,四川成都611130

出　　处：《核农学报》2016年第9期1722-1730,共9页Journal of Nuclear Agricultural Sciences

基　　金：高等学校博士学科点专项科研基金(20125103110007)

摘　　要：脱落酸(ABA)是一种重要的植物激素,调节多种植物生理过程,并在植物应答逆境胁迫的信号转导中起重要作用。结构分子生物学分析发现,PYL蛋白具有结合ABA的活性中心。在非胁迫条件下,ABA水平较低,2C型蛋白磷酸酶(PP2C)与蔗糖非酵解型蛋白激酶2(SnRK2)结合,催化其去磷酸化而抑制其活性;在胁迫条件下,ABA水平升高,促进PYL与PP2C结合而抑制其磷酸酶活性,SnRK2靠自身磷酸化激活,又催化碱性亮氨酸拉链(b ZIP)、碱性螺旋-环-螺旋(b HLH)等类型转录因子,调控下游抗性相关基因的表达,也可由SnRK2直接催化下游抗性相关蛋白磷酸化。本文概述了在ABA胁迫下,PYL,PP2C和Sn PK2作用机制的相关研究进展,并建议将PYL、PP2C和SnRK2分别称做ABA信号转导途径的直接受体、第二信使和第三信使,建立玉米中复杂的脱落酸信号上淳传递网络。Abscisic acid （ABA） is a phytohormone. It regulates many physiological processes, and also mediates signal transduction in plant responses to inclement environments. Analysis of structural molecular biology elucidated that pyrabactin resistance 1 - like protein （PYL） has an activity center for ABA binding. ABA level ramains low under non- stress inclement environments. Protein phosphatase type 2C （PP2C） binds to sucrose non-fermentingl -related protein kinase 2 （SnRK2） , catalyses its dephosphorylation and inhibits its activity. In inclement environments, increasing ABA promotes PYL to bind to PP2C and inhibits its dephosphorylation activity. SnRK2 is activated by autophosphorylation, catalyses phosphorylation of basic leucine zipper, basic helix-loop-helix and other kinds of transcription factors, and controls the expression of downstream resistance-related genes, or directly catalyses the phosphorylation of downstream resistance-related proteins. This paper summaries the research advances of the mechanism of PYL, PP2C and SnRK2 under the stress of ABA, and suggests to define PYL,PP2C and SnRK2 as the direct perceptor, the second messenger, and the third messenger of ABA signal transduction pathway, respectively and establish complicated abscisic acid of corn upstream signal transmission network.

关 键 词：脱落酸 植物 信号转导 上游信使 

分 类 号：Q946.885.6[生物学—植物学]