KINASE MEDIATED SIGNALING IN THE RICE DEFENSE RESPONSE

受体激酶(RKS)在血管紧张素转换酶的作用机制中起着重要作用。 生物体对环境信号的感知和反应；调节 动物和植物的生长和发育。的长期目标是 建议的项目是引出监管的信号交易级联 由RKS。这些信息将增强我们对细胞 在动物中转化和致癌，并导致发育 在植物中控制疾病的环境安全策略。 拟议项目的短期目标是确定因果关系 病原菌诱导水稻受体样蛋白激活之间的关系 KK、Xa21以及下游的防御反应。基于信息 根据动物系统中的受体酪氨酸激酶，我们假设 Xa21催化结构域在Xa21介导的信号转导中起关键作用 转导和特定残基作为细胞内结合位点 蛋白质。然后这些蛋白质可以直接或间接转导不同的 防御反应。我们还假设病原体可能会分泌 进入宿主细胞的影响信号转导途径的因素。 在部分支持这些假设的情况下，我们发现 细胞内结构域在体外可以自我磷酸化，这是一种 病原菌GTP结合蛋白与水稻过氧化氢酶的特异性相互作用 随着Xa21在植物中发生抗性反应。为了测试这些 在假设条件下，我们建议实现以下目标：1.确认 磷酸化在Xa21介导的抗病中的重要作用。 2.鉴定和鉴定与Xa21相互作用的水稻蛋白- 激活剂。3.鉴定防御反应和防御相关基因 在Xa21介导的防御途径中的表达。4.确定 XOO/GBP相互作用的生物学意义。取得的成就 拟议的目标将首次导致建立 植物受体激酶与相关受体之间的因果关系 下游响应。

Receptor kinases (RKs) play an important role in the mechanisms witch which organisms perceive and respond to environmental signals; regulating growth and development in both animals and plants. The long-term goal of the proposed project is to elicit the signal transaction cascade regulated by RKs. This information will enhance our understanding of cellular transformation and carcinogenesis in animals and lead to the development of environmentally safe strategies for disease control in plants. The short-term goal of the proposed project is to establish the causal connection between pathogen induced activation of the rice receptor-like kinase, XA21, and the downstream defense responses. Based on information from receptor tyrosine kinases in animal systems, we hypothesize that the catalytic domain of XA21 plays a key role in XA21-mediated signal transduction and that specific residues as binding sites for intracellular proteins. These proteins may then directly or indirectly transduce various defense responses. We also hypothesize that the pathogen may secrete factors into the host cell that influence the signal transduction pathway. In partial support of these hypotheses, we have found that the intracellular domain can autophosphorylate itself in vitro, that a pathogen GTP-binding protein and a rice catalase interact specifically with the XA21 in plants undergoing a resistance response. To test these hypotheses, we propose to carry out the following objectives: 1. Confirm the essential role of phosphorylation in XA21-mediated disease resistance. 2. Identify and characterize rice proteins that interact with the Xa21- kinase. 3. Characterize the defense response and defense-related gene expression in the XA21-mediated defense pathway. 4. Determine the biological significance of the xoo/GBP interaction. Accomplishments of the proposed objectives will, for the first time, lead to the establishment of the causal connection between a plant receptor kinase and the associated downstream response.