Dissection of AvrBsT-BST defense pathway in Arabidopsis

拟南芥 AvrBsT-BST 防御途径的剖析

• 批准号: 7494942
• 负责人: Mary Beth MUDGETT
• 金额: $ 25.89万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-30 至 2009-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7494942
• 关键词: Affect; Animals; Arabidopsis; Bacteria; Bacterial Proteins; Cell Communication; Cells; Cleaved cell; Cysteine Protease; Data; Disease; Disease Resistance; Dissection; Endopeptidases; Family; Genes; Genetic Screening; Goals; Growth; Infection; Maps; Microbe; Molecular; Numbers; Pathogenesis; Pathway interactions; Peptide Hydrolases; Physiology; Plant Physiology; Plants; Post-Translational Protein Processing; Protein Isoforms; Proteins; Proteolysis; Resistance; Role; Signal Transduction; Signal Transduction Pathway; Specificity; Staging; Stress; Symptoms; System; Type III Secretion System Pathway; Ubiquitin; Virulence; Work; Xanthomonas; Xanthomonas campestris; base; defense response; genetic analysis; genetic regulatory protein; insight; mutant; pathogen; response

Bacterial pathogens of plant and animals use the type III secretion (T3S) system and effector protein substrates to alter eukaryotic physiology to promote bacterial multiplication and host colonization. The large repertoire of T3S effectors (~20-30 proteins) in plant pathogenic bacteria predicts that multiple nodes in plant signaling cascades are being targeted. The identity of the plant targets and the biochemical mechanisms by which these T3S effector proteins manipulate plant physiology however are poorly understood. Extensive phenotypic studies support the concept that many of the T3S effectors suppress the plant immune system to colonize tissues. This illuminates the importance of basal defense responses and resistance (R) protein- mediated innate immune responses in controlling the outcome of bacterial infections in the plant kingdom. Understanding how plant immunity is regulated and how bacterial pathogens manipulate their hosts is fundamental knowledge required for the prevention and elimination of plant disease. The long-term goal of this project is elucidate how plants integrate lipid signals to respond to bacterial infection. Two conserved eukaryotic proteins - SOBER1, a lipase and CIP, a putative apolipoprotein - have been identified and shown to be important regulators of innate immune responses in plants. Genetic and biochemical studies will be performed using the Arabidopsis pathosystem to characterize SOBER1 and CIP substrate specificity and to determine the mechanisms by which these proteins control phospholipid metabolism and signaling during bacterial infection. Studies will also be aimed to determine the biochemical mechanisms by which the pathogen T3S effector AvrBsT perturbs lipid homeostasis within infected plant cells. This work is expected to provide fundamental insight to the biochemical mechanisms used by plants to control lipid metabolism and signaling in response to pathogen attack. The growing body of evidence suggesting an interplay between lipid metabolism and immunity in both plants and animals indicates that fundamental knowledge about how lipid signals are initiated and terminated will be essential to fully understand how the immune system is regulated in eukaryotes.

动植物的细菌病原体使用 III 型分泌 (T3S) 系统 效应蛋白底物改变真核生理学以促进细菌 繁殖和宿主定植。 T3S 效应器的大量曲目（~20-30 植物病原菌中的蛋白质）预测植物信号传导中的多个节点 级联正在成为目标。植物靶标的身份和生化 然而，这些 T3S 效应蛋白操纵植物生理的机制 人们了解甚少。广泛的表型研究支持这样的概念：许多 T3S 效应子抑制植物免疫系统在组织中定殖。这 阐明基础防御反应和抵抗 (R) 蛋白的重要性 - 介导的先天免疫反应控制细菌感染的结果 植物王国。了解植物免疫是如何调节的以及细菌是如何调节的 病原体操纵宿主是预防所需的基础知识 和消除植物病害。 该项目的长期目标是阐明植物如何将脂质信号整合到 对细菌感染作出反应。两种保守的真核蛋白 - SOBER1，一种脂肪酶 和 CIP（一种推定的载脂蛋白）已被鉴定并被证明很重要 植物先天免疫反应的调节剂。遗传和生化研究将 使用拟南芥病理系统来表征 SOBER1 和 CIP 底物特异性并确定这些蛋白质控制的机制 细菌感染期间的磷脂代谢和信号传导。研究也将 旨在确定病原体 T3S 效应子的生化机制 AvrBsT 扰乱受感染植物细胞内的脂质稳态。这项工作预计将 提供对植物用于控制的生化机制的基本见解 响应病原体攻击的脂质代谢和信号传导。不断成长的身体 有证据表明两种植物的脂质代谢和免疫之间存在相互作用 动物表明有关脂质信号如何启动的基本知识 和终止对于充分了解免疫系统是如何调节的至关重要 在真核生物中。