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，avr和R这两个基因必须存在。对这种相互作用的最简单的解释是受体-配体模型，其中抗性基因产物（R蛋白）直接或间接地识别由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，导致多种局部和全身防御反应的激活。拟南芥的NDR 1是几个CC/NBS/LRR抗性基因活性所必需的，并且NDR 1的过量表达提供了剂量依赖性的增强的细菌抗性。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。定位在质膜上将使NDR 1与细菌-植物细胞界面紧密接触。本项目的目的是利用遗传学和生物化学相结合的方法来确定NDR 1在拟南芥病原菌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.