一个flg22诱导的,G蛋白依赖网络中的酸化动态揭示了AtRGS1酸酶
Justin M Watkins1, Christian Montes2, Natalie M Clark2
1Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.
Molecular & cellular proteomics : MCP
|December 22, 2023
概括
植物免疫反应涉及到快速的蛋白质变化,特别是G蛋白信号传递. 一种蛋白质酸酶2A复合体,PP2A(ATBα),调节AtRGS1的降解,维持先天免疫信号传递.
科学领域:
- 植物分子生物学 植物分子生物学
- 植物免疫学 植物免疫学
- 细胞信号传递 细胞信号传递
背景情况:
- 与微生物相关的分子模式flg22触发了植物的免疫反应.
- 旗素感应涉及旗素敏感2 (FLS2) 和异三基G蛋白合信号通路.
研究的目的:
- 在flg22感知时调查Arabidopsis根细胞中的蛋白质和蛋白质变化.
- 阐明异构三基G蛋白复合体及其相互作用体在flg22诱导的信号传递中的作用.
- 为了确定Arabidopsis thalianaG信号1 (AtRGS1) 蛋白质稳定性和信号的G信号1 (AtRGS1) 调节者的关键调节者.
主要方法:
- 野生类型 (WT) 和突变的阿拉比多普西斯根细胞的定量蛋白质组学和光蛋白质组学分析.
- 在异构三分子G蛋白相互作用组内对蛋白质-蛋白质相互作用的分析.
- 基因操纵 (ATBα的零突变) 和蛋白质内细胞分裂和降解的评估.
主要成果:
- flg22治疗诱导了Arabidopsis根细胞中蛋白质丰度和酸化的巨大变化.
- 这些变化集中在异构三级G蛋白相互作用体和免疫网络枢纽中.
- 大约95%的G蛋白相互作用体中的酸化变化取决于功能性的G蛋白复合体.
- 蛋白酸酶2A (PP2A) 复合体,特别是它的ATBα子单元,与AtRGS1.1相互作用.
- 失去ATBα会导致AtRGS1内细胞和蛋白质体降解的增加,从而降低AtRGS1水平.
结论:
- PP2A(ATBα) 综合体是flg22诱导的先天性免疫信号的关键调节者.
- 以酸化为依赖的内分细胞和由PP2A(ATBα) 降解AtRGS1的蛋白质体,维持异构三级G蛋白复合体的激活.
- 这种机制对于调节植物天生的免疫力学的动态至关重要.
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