Calcium-Dependent Protein Kinases in Plant Defense Signaling

本研究旨在阐明钙依赖蛋白激酶(CDPKs)介导植物早期防御信号转导的分子机制。最近的发现表明，在植物、昆虫和哺乳动物的先天性免疫反应中，富含亮氨酸重复序列(LRR)的受体在识别病原体相关分子模式(PAMP)方面具有显著的保守性。植物细胞似乎拥有许多传感器来检测非自体PAMP，并发起收敛和特定的防御反应。一个基于不同PAMPs诱导早期防御基因表达的拟南芥叶细胞系统，包括鞭毛蛋白、脂多糖、Harpin(分泌细菌蛋白)、NPP1(表面真菌坏死诱导疫霉蛋白1)和几丁质(真菌细胞壁成分)，将用于研究植物中的先天免疫信号。这项新的研究将集中在阐明一组CDPKs在先天性免疫反应中控制的信号通路。以细胞为基础的系统和反向遗传学极大地促进了功能基因组学方法的应用，以确定多个CDPKs在由不同病原体启动的汇聚和特定信号事件中的确切作用。该项目将为多学科学术环境中的研究员和本科生/研究生提供极好的培训机会，包括社区服务和支持妇女和少数民族科学家的综合方案。PAMP信号转导在天然免疫反应中的分子机制是植物防御中一个非常新的领域。拟南芥细胞系统是近几年发展起来的。这项由美国国家科学基金会赞助的研究计划将在理解植物先天免疫反应方面取得一些重大突破。由于PAMP介导的信号是一种更普遍和保守的防御机制，这项工作可能会创造出新的工具，用于产生对植物中更广泛的病原菌更持久的抗病能力，并改善农业。该项目产生的信息和材料将提供给工厂社区。

The goal of the research project is to elucidate the molecular mechanisms underlying early defense signal transduction mediated by calcium-dependent protein kinases (CDPKs) in plants. Recent discoveries have revealed remarkable conservation in the recognition of pathogen-associated molecular patterns (PAMPs) by leucine-rich-repeat (LRR) receptors in innate immune responses from plants, insects, to mammals. Plant cells appear to possess many sensors to detect non-self PAMPs and launch convergent as well as specific defense responses. An Arabidopsis leaf cell system based on the induction of early defense gene expression by diverse PAMPs, including flagellin, LPS (lipopolysaccharide), harpin (a secreted bacterial protein), NPP1 (a surface fungal necrosis-inducing Phytophthora protein 1) and chitin (a fungal cell-wall component), will be used to study innate immune signaling in plants. The new research will focus on the elucidation of signaling pathways controlled by a group of CDPKs in innate immune responses. The cell-based system and reverse genetics greatly facilitate the application of a functional genomic approach to determine the precise roles of multiple CDPKs in convergent and specific signaling events initiated by diverse pathogens. The project will provide excellent training opportunities for research fellows and undergraduate/graduate students in a multidisciplinary academic environment with integrated programs for community services and for supporting woman and minority scientists. The molecular mechanisms mediating PAMP signaling in innate immune response is a very new area in plant defense. The Arabidopsis cell-based system is recently developed. Some major breakthroughs in the understanding of plant innate immune responses will be generated through this NSF-sponsored research program. Because the PAMP-mediated signaling is a more general and conserved defense mechanism, the work may create new tools for the generation of more durable disease resistance to a broader spectrum of pathogens in plants and improve agriculture. Information and materials generated from this project will be available to the plant community.