Characerization of NDR1 in Arabidopsis thaliana

描述（由申请人提供）：在20世纪40年代，Flor提出了现在经典的基因对基因模型来解释植物对细菌病原体抗性的分子基础。简而言之，该模型表明，为了使植物对给定的病原体具有抗性，必须同时存在avr和R两个基因。对这种相互作用最简单的解释是受体-配体模型，即抗性基因产物（R蛋白）直接或间接识别细菌无毒基因产物指定的配体。受体对配体的识别被认为启动信号转导级联，导致各种局部和全身防御反应的激活。拟南芥的几种CC/NBS/LRR抗性基因的活性都需要NDR1，并且NDR1的过表达提供了剂量依赖性的细菌抗性增强。计算机分析表明NDR 1可能是gpi锚定蛋白，因此可能是质膜定位的。在质膜上定位将使NDR1与细菌-植物细胞界面密切接触。本项目的目标是利用遗传和生化方法的结合来确定NDR1在拟南芥病原体诱导的防御反应中所起的作用。

DESCRIPTION (provided by applicant): In the 1940s, Flor proposed the now classic gene-for-gene model to explain the molecular basis of a plant's resistance to a bacterial pathogen. In short, this model suggests that in order for a plant to be resistant to a given pathogen, both genes, avr and R, must be present. The simplest explanation for this interaction is the receptor-ligand model, whereby the resistance gene products (R proteins) recognize, either directly or indirectly, the ligands specified by the bacterial avirulence gene products. Recognition of the ligand by the receptor is thought to initiate a signal transduction cascade leading to the activation of a variety of local and systemic defense responses. NDR1 of Arabidopsis is required for the activity of several CC/NBS/LRR resistance genes, and over-expression of NDR1 provides a dose-dependent enhanced bacterial resistance. Computer analyses suggest that NDR 1 may be a GPI-anchored protein, and as such, may be plasma membrane-localized. Localization at the plasma membrane would place NDR1 in intimate contact with the bacteria-plant cell interface. The goal of this project is to utilize a combination of genetic and biochemical approaches to identify the role NDR1 plays in the pathogen-induced defense response in Arabidopsis.