辅助NLRs Nrc2和Nrc3与Prf/Pto相互依赖,并激活MAPK信号,以诱导番茄的免疫力
Ning Zhang1,2, Joyce Gan1, Lauren Carneal1
1Boyce Thompson Institute for Plant Research, Ithaca, New York, 14853, USA.
The Plant journal : for cell and molecular biology
|October 16, 2023
概括
番茄助手NLRs Nrc2和Nrc3对于植物对Pseudomonas syringae的免疫力至关重要. 这些蛋白质与传感器NLR Prf和Pto kinase起作用,在MAPK信号的上游作用,激活防御反应.
科学领域:
- 植物免疫力 植物免疫力
- 分子植物微生物相互作用.
- 植物细胞的信号传递.
背景情况:
- 植物细胞内免疫受体,核酸结合,富含白素的重复蛋白 (NLRs),检测病原体效应物并触发NLR触发的免疫力 (NTI).
- 最近的研究表明",传感器"NLR与"助手"NLR合作激活植物免疫力.
- 番茄 (Solanum lycopersicum) 是 Pseudomonas syringae pv. 的一种细菌病原体. 番茄 (Pst) 是研究植物防御机制的模型病原体.
研究的目的:
- 为了研究两个辅助NLRs,Nrc2和Nrc3,在番茄对Pst.免疫力中的作用.
- 阐明Nrc2和Nrc3在Prf/Pto介导免疫通路中的功能机制.
- 确定Nrc2和Nrc3在导致工厂防御的信号级联中的位置.
主要方法:
- 生成的番茄突变体缺乏Nrc2和/或Nrc3 (nrc2,nrc3,nrc2/nrc3) 的发生.
- 评估了植物对表达效应因子AvrPto和AvrPtoB.的Pst菌株的敏感性.
- 分析了通过各种免疫受体变体和下游信号组件 (MAPK激活) 诱导编程细胞死亡 (PCD).
主要成果:
- nrc2/nrc3双突变完全失去了Prf/Pto介导的NTI对Pst,而nrc3和nrc2突变分别表现出中等和轻度的敏感性.
- Nrc2和Nrc3在Prf/Pto介导免疫中具有添加作用.
- 在nrc2/3突变体中,由AvrPtoB,Pto或Prf诱导的PCD被废除,AvrPto的MAPK激活被废除,表明Nrc2/Nrc3在MAPK信号的上游起作用.
结论:
- Nrc2和Nrc3是必不可少的辅助NLRs,它们与NLR Prf和Pto激酶的传感器一起起作用,在番茄免疫中对Pst.
- 这些辅助NLRs在MAPK信号通路上游起作用,在启动植物防御反应方面发挥着关键作用.
- Nrc2和Nrc3特别参与Prf/Pto介导的免疫,但不参与Ptr1介导的耐药性,突出显示了该途径的特异性.
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