Role of organelle dynamics and retrograde signaling during plant innate immunity

细胞器动力学和逆行信号在植物先天免疫过程中的作用

• 批准号: 10380113
• 负责人: Jeffrey L Caplan
• 金额: $ 46.42万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-06-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10380113
• 关键词: Actins; Affect; Animals; Apoptosis; Automobile Driving; Bacteria; Binding; Biological; Biological Models; Cell Death; Cell Nucleus; Cell membrane; Cell surface; Cells; Cellular biology; Chloroplasts; Communicable Diseases; Communication; Cytoskeleton; Cytosol; Development; Flagellin; Generations; Genetic; Genetic Screening; Goals; Hormones; Hydrogen; Hydrogen Peroxide; Hypersensitivity; Image Analysis; Immune; Immune response; Immune signaling; Immunity; Immunologic Receptors; Infection; Innate Immune Response; Kinesin; Label; Leucine-Rich Repeat; MAP Kinase Gene; Measures; Microfilaments; Microtubules; Mitochondria; Modeling; Molecular; Morphology; Motor; Movement; NADPH Oxidase; Nanotubes; Natural Immunity; Nuclear; Nucleotides; Organelles; Pattern; Pattern recognition receptor; Peroxides; Phosphotransferases; Plants; Play; Positioning Attribute; Process; Proteins; Proteomics; Pseudomonas syringae; RIPK1 gene; Reactive Oxygen Species; Regulation; Research; Role; Salicylic Acids; Signal Transduction; Source; System; Testing; Tubular formation; Vertebrates; Virulence; base; extracellular; forward genetics; genetic approach; insight; mutant; novel; organelle movement; pathogen; prevent; receptor; recruit; response; screening; superoxide-generating NADPH oxidase

1 Project Summary 2 This project focuses on the chloroplast as central player in the generation of immune signals and the 3 regulation of programmed cell death (PCD) required for innate immune responses against pathogen infection. 4 Although mitochondria play a central role during mammalian PCD, emerging evidence suggests that in plants 5 chloroplasts have a critical function in executing localized PCD that limits pathogen spread. Chloroplasts in 6 addition to being involved in the generation of immune signals, such as reactive oxygen species (ROS) and the 7 defense hormone salicylic acid (SA), also participate directly in the recognition of pathogens. Interestingly, 8 chloroplasts dynamically change their morphology during immune responses and send out stroma-filled tubular 9 projections called stromules. These induced stromules use the cytoskeleton to extend and then anchor to the 10 nucleus, which facilitate perinuclear clustering of chloroplasts and transport of chloroplast-generated hydrogen 11 peroxide (H2O2) ROS and defense proteins to the nucleus. The overall goal of this application is to use a 12 combination of novel cell biology, genetics, proteomics and computational approaches to unravel the 13 mechanistic basis of stromule formation and their role in driving perinuclear chloroplast clustering and 14 subsequent release of retrograde immune signals from chloroplasts to nuclei. Specifically, Aim 1 will identify 15 and characterize proteins required for stromule formation and stromule-directed chloroplast movement. This 16 includes the kinesin motor required for extension and proteins associated with the outer envelope of stromules 17 that may drive stromule initiation or regulation. An unbiased forward genetic screen will be conducted to 18 identify other stromule specific components. Aim 2 will investigate immune signals required for stromule 19 induction and the release of H2O2 as a specific retrograded chloroplast signal. The role of stromules in 20 amplification of immune signaling consisting of SA and H2O2 signaling will be examined. The relationship of 21 different H2O2 sources, organelle movement and PCD during immune responses will be studied to determine 22 how H2O2 propagates extracellularly to intracellular sources to regulate innate immune responses. The function 23 of stromules and chloroplast positioning during H2O2 signal propagation will be examined using the stromule- 24 specific mutants characterized in Aim 1. Aim 3 will focus on how pathogen effectors affect stromules, 25 organelle, and cytoskeleton dynamics as a virulence strategy. In addition, mechanistic basis of how three 26 effectors disrupt stromules and organelle dynamics will be determined. Understanding the role of different 27 organelles during PCD and innate immunity will provide a unified mechanistic basis of cell death and cell 28 survival process that occur in response to infectious pathogens. The results from our model systems will 29 impact broadly on understanding of organelle-to-nuclear communication that influence innate immunity against 30 infectious diseases.

1个项目摘要 2该项目的重点是叶绿体作为免疫信号的中心参与者和 3对病原体感染的先天免疫反应所需的程序性细胞死亡（PCD）调节。 4尽管线粒体在哺乳动物PCD期间起着核心作用，但新出现的证据表明，在植物中 5个叶绿体在执行局部PCD方面具有关键功能，从而限制病原体扩散。叶绿体中 6还包括参与免疫信号的产生，例如活性氧（ROS）和 7防御激素水杨酸（SA）也直接参与病原体的识别。有趣的是， 8叶绿体在免疫反应过程中动态改变其形态，并发送纤维纤维 9个预测称为Stromules。这些诱导的基因使用细胞骨架延伸，然后锚定在 10个核，促进叶绿体的核周聚类和叶绿体生成的氢的转运 11过氧（H2O2）ROS和防御蛋白到细胞核。该应用程序的总体目标是使用 12新型细胞生物学，遗传学，蛋白质组学和计算方法的结合，以阐明 13茎形成的机理基础及其在驱动核周叶绿体聚类和 14随后释放从叶绿体到核的逆行免疫信号。具体来说，AIM 1将确定 15并表征stom子形成和stromule导向叶绿体运动所需的蛋白质。这 16包括延伸和蛋白质所需的动力素电动机 17可能会驱动基质的启动或调节。公正的前遗传屏幕将进行 18识别其他特定组件。 AIM 2将研究Stromule所需的免疫信号 19诱导和H2O2作为特定逆行叶绿体信号的释放。 stromules在 20将检查由SA和H2O2信号组成的免疫信号的扩增。关系 将研究21种不同的H2O2源，在免疫反应过程中的细胞器运动和PCD以确定 22 H2O2如何在细胞外传播到细胞内来源以调节先天免疫反应。功能 H2O2信号传播期间的23个stromules和叶绿体定位将使用Stromule- 24个特征在AIM 1中的特定突变体。AIM3将集中于病原体效应子如何影响基因杆，， 25细胞器和细胞骨架动力学作为毒力策略。此外，如何三个 26效应子将破坏基因和细胞器动力学。了解不同的角色 27 PCD和先天免疫期间的细胞器将提供细胞死亡和细胞的统一机械基础 28响应感染性病原体而发生的生存过程。我们的模型系统的结果将 29广泛地影响了对细胞器到核交流的理解，这些沟通会影响先天免疫力 30种传染病。