Dissectation of an EDM-2-Dependent Signaling Mechanism Mediating Resistance to Hyaloperonospora Parasitica in Arabidopsis

植物病害是造成作物生产严重损失的原因。植物对病原微生物的抗性通常是由抗病基因介导的，抗病基因介导病原体的识别并引发防御反应。准确调控R基因活性水平对其功能至关重要。然而，R基因的调控机制尚不清楚。最近发现的EDM2蛋白是一种控制R基因转录（mRNA合成）的新型调节剂。利用酵母双杂交系统（一种检测蛋白质/蛋白质相互作用的体内试验）筛选出多种与EDM2物理相互作用的蛋白质。结合遗传和生化方法，研究EDM2及其相互作用伙伴在调节R基因活性和抗病中的分子作用。在未经处理和防御激活的植物中，将分析EDM2与其可能的伴侣之间的物理相互作用。编码EDM2及其互作伙伴基因突变的植物系将被测试对R基因活性的影响。此外，这些蛋白与R基因的调控DNA区域的结合将被检查和表征。这些研究将增加我们对R基因调控机制细节的理解，并将提供植物免疫系统几个新成分的详细表征。更广泛的影响：这个项目的一个重要组成部分是本科生的强烈参与，主要来自少数民族。该项目将与加州大学河滨分校植物细胞生物学中心内正在进行的NSF-REU植物细胞生物学项目相关联。此外，该项目将为培养分子遗传学、基因组学和植物病理学等领域的博士后和研究生提供良好的平台。这项研究的结果可能允许设计新的策略，通过操纵EDM2及其相互作用物的功能来提高作物的抗病能力。

Plant diseases are the cause for dramatic losses in crop production. Resistance of plants to pathogenic microorganisms is often mediated by disease resistance (R) genes that mediate recognition of pathogens and trigger defense reactions. Accurate regulation of R gene activity levels is critical for their function. However, mechanisms of R gene regulation are not well understood. The recently identified EDM2 protein is a novel regulator that controls transcription (mRNA synthesis) of R genes. Screens using the yeast two-hybrid system (an in vivo assay detecting protein/protein interactions) identified multiple proteins that physically interact with EDM2. Combining genetic and biochemical methods molecular roles of EDM2 and its interaction partners in regulating R gene activity and disease resistance will be examined. Physical interactions between EDM2 and its putative partners will be analyzed in untreated and defense-activated plants. Plant lines with mutations in the genes encoding EDM2 and its interaction partners will be tested for effects on the activities of R genes. In addition, binding of these proteins to regulatory DNA regions of R genes will be examined and characterized. These studies will increase our understanding of mechanistic details of R gene regulation and will provide a detailed characterization of several novel components of the plant immune system. Broader impacts: An important component of this project is strong involvement of undergraduate students, mainly from minority groups. The project will be linked to the ongoing NSF-REU Plant Cell Biology program within the Center for Plant Cell Biology at UC-Riverside. In addition, the project will provide an outstanding platform for training of postdoctoral scholars and graduate students in the fields of molecular genetics, genomics and phytopathology. Results from this study are likely to allow the design of new strategies to improve disease resistance in crops by manipulating function of EDM2 and its interactors.