Effector Recognition and Molecular Activation of an Arabidopsis NLR Immune Receptor Specifying Disease Resistance to Hyaloperonospora arabidopsidis

拟南芥 NLR 免疫受体的效应子识别和分子激活，指定对拟南芥膜孢菌的抗病性

• 批准号: 1146793
• 负责人: Brian Staskawicz
• 金额: $ 70万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-15 至 2016-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1146793&HistoricalAwards=false
• 关键词: Effector; Recognition; Molecular; Activation; Arabidopsis

Plants face continuous attacks by pathogenic microbes and rely on a sophisticated immune system to ward them off. Central to this immune system are intracellular resistance proteins that recognize microbe-derived effector proteins and induce physiological changes in the plant cell that ultimately lead to localized cell death and containment of the invading pathogen. This project aims at investigating in more detail one such resistance protein/effector pair RPP1/ATR1 in the model system Arabidopsis/downy mildew and to gain a better understanding of the molecular events involved in effector recognition and resistance protein activation. The investigators will use genetic and biochemical approaches to obtain definitive evidence for direct interaction between RPP1 and ATR1. Isolation of pure protein extracts of resistance proteins has been challenging, thus the investigators will employ in planta expression systems to obtain enough RPP1 protein to perform direct interaction studies with ATR1 through co-crystallization and protein pull-down experiments. Random mutagenesis of both resistance and effector proteins will provide an exhaustive map of amino acid residues that are crucial for the interaction of these proteins. Precise timing and localization of resistance proteins is imperative during an immune response. RPP1 contains signal sequences that target the protein to the nucleus and/or membrane. In this project the investigators will determine the effect of mutating these signal sequences on RPP1-mediated resistance. Finally, resistance protein activation will be studied using biochemical approaches to identify proteins associating with RPP1 prior to and upon effector recognition. Taken together, results from this project will enhance our basic understanding of plant disease resistance signaling, which may ultimately be translated into agricultural research and result in more sustainable approaches of crop protection. The project will provide training for pre- and post-doctoral fellows as well as undergraduate students.

植物面临着病原微生物的持续攻击，并依靠复杂的免疫系统来抵御它们。该免疫系统的核心是细胞内抗性蛋白，其识别微生物衍生的效应蛋白并诱导植物细胞中的生理变化，最终导致局部细胞死亡和对入侵病原体的遏制。本项目旨在更详细地研究拟南芥/霜霉病模型系统中的一个这样的抗性蛋白/效应子对RPP 1/ATR 1，并更好地了解效应子识别和抗性蛋白激活所涉及的分子事件。研究人员将使用遗传和生物化学方法来获得RPP 1和ATR 1之间直接相互作用的确切证据。分离抗性蛋白的纯蛋白提取物具有挑战性，因此研究人员将采用植物表达系统获得足够的RPP 1蛋白，通过共结晶和蛋白下拉实验与ATR 1进行直接相互作用研究。抗性和效应蛋白的随机诱变将提供对这些蛋白的相互作用至关重要的氨基酸残基的详尽图谱。在免疫应答期间，抗性蛋白的精确定时和定位是必要的。RPP 1含有将蛋白质靶向细胞核和/或细胞膜的信号序列。在这个项目中，研究人员将确定这些信号序列突变对RPP 1介导的抗性的影响。最后，抗性蛋白的激活将使用生物化学方法进行研究，以确定与RPP 1相关的蛋白质之前和之后的效应识别。总之，该项目的结果将增强我们对植物抗病信号的基本理解，最终可能转化为农业研究，并导致更可持续的作物保护方法。该项目将为博士前和博士后研究员以及本科生提供培训。