Study of chloroplast stromules during PCD and inter-organellar communication

PCD 和细胞间通讯过程中叶绿体基质的研究

基本信息

批准号：
9382027
负责人：
Jeffrey L Caplan
金额：
$ 32.22万
依托单位：
UNIVERSITY OF CALIFORNIA AT DAVIS
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-07-15 至 2019-05-19
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9382027
关键词：
Actins Animals Apoptosis Binding Biological Models Carrier Proteins Cell Death Cell Nucleus Cell Survival Cell membrane Cell surface Cellular biology Chloroplasts Communicable Diseases Communication Complex Computing Methodologies Cytoplasm Cytoskeleton Development Disease Flagellin Generations Genetic Goals Growth and Development function Hormones Hydrogen Peroxide Hypersensitivity Immune Immune response Immune signaling Immunity Immunologic Receptors Infection Innate Immune Response Knock-out Leucine-Rich Repeat MAP Kinase Gene Malignant Neoplasms Mammals Mass Spectrum Analysis Measures Membrane Microfilaments Microtubules Mitochondria Modeling Molecular Morphology Movement NADPH Oxidase Natural Immunity Nuclear Nucleotides Organelles Pattern Pattern recognition receptor Phosphotransferases Plants Play Process Proteins Proteomics Publishing RIPK1 gene Reactive Oxygen Species Recruitment Activity Regulation Research Role Salicylic Acids Signal Transduction Signaling Protein Source Testing Tubular formation Vertebrates Virulence base extracellular genetic analysis genetic approach immune function insight mutant novel optogenetics organelle movement pathogen prevent protein biomarkers protein transport receptor response superoxide-generating NADPH oxidase tool

项目摘要

Project Summary This project focuses on chloroplasts as central player in the generation of immune signals and the regulation of programmed cell death (PCD) required for innate immune responses against pathogen infection. Although mitochondria play a central role during mammalian PCD, emerging evidence suggests that in plants chloroplasts have a critical function in executing localized PCD that limits pathogen spread. Chloroplasts in addition to being involved in the generation of immune signals such as reactive oxygen species (ROS) and defense hormone salicylic acid (SA), also participate directly in the recognition of pathogen. Interestingly, the chloroplasts dynamically change their morphology during immune responses and send out tubular projections called stromules. These induced stromules use the cytoskeleton to extend and then anchor to the nucleus, which facilitate perinuclear clustering of chloroplasts and transport chloroplast-generated ROS and defense proteins to the nucleus. The overall goal of this application is to use combination of novel cell biology, genetics, proteomics and computational approaches to unravel the mechanistic basis of stromule driven periunclear chloroplast clustering and determine the identity and function of immune signals released from chloroplasts to nuclei. Specifically, Aim 1 will examine organelle and cytoskeleton dynamics during plant innate immunity. Novel computational methods quantifying stromule features and dynamics will be further developed and applied to understand chloroplasts, their stromules, and cytoskeleton dynamics during innate immunity. Both plant and animal pathogens target the cytoskeleton, and this aim will examine how pathogen effectors alter the cytoskeleton and related organelle dynamics as a virulence strategy. Aim 2 will investigate immune signals required for stromule induction and the release of chloroplast signals. The relationship of different ROS sources, organelle movement and PCD during immune responses will be examined using a combination of genetic tools and the computational methods developed in Aim 1. In Aim 3, known chloroplast-derived immune signals will be characterized and novel protein signals will be identified. The downstream targets of H2O2 in the nucleus will be elucidated and studied. Mass spectrometry will be used to identify proteins that are transported from chloroplasts to nuclei. Genetic approaches will be employed to examine their role during PCD. Lastly, the mechanism of release from chloroplasts during innate immunity will be studied to determine if it is akin to mitochondrial release during apoptosis in mammals. Understanding the role of different organelles during PCD and innate immunity will provide a unified mechanistic basis of cell death and cell survival process that occur in response to infectious pathogens. The results from our model systems will impact broadly on understanding of organelle-to-nuclear communication that influence innate immunity against infectious diseases.

项目摘要该项目的重点是叶绿体作为免疫信号的中心参与者和针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。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。叶绿体中还参与了免疫信号的产生，例如活性氧（ROS）和防御激素水杨酸（SA）也直接参与病原体的识别。有趣的是，叶绿体在免疫反应过程中动态改变其形态并发送管状投影称为stromules。这些诱导的基因群使用细胞骨架延伸，然后锚定在细胞核上，这有助于叶绿体的核周聚类和运输叶绿体生成的ROS和防御蛋白质到细胞核。该应用的总体目标是使用新型细胞生物学，遗传学，蛋白质组学和计算方法，以阐明stromule驱动的毛刺的机理基础叶绿体聚类并确定从叶绿体释放到的免疫信号的身份和功能核。具体而言，AIM 1将检查植物先天免疫期间的细胞器和细胞骨架动力学。量化基质特征和动力学的新型计算方法将得到进一步开发，并且用于了解先天免疫期间的叶绿体，其stromules和细胞骨架动力学。两个都动植物病原体靶向细胞骨架，此目的将检查病原体效应子如何改变细胞骨架和相关细胞器动力学作为毒力策略。 AIM 2将调查免疫信号茎诱导和叶绿体信号的释放所需。不同ROS的关系在免疫反应期间的来源，细胞器的运动和PCD将通过组合进行检查 AIM 1中开发的遗传工具和计算方法。在AIM 3中，已知的叶绿体衍生的免疫信号将被表征，并确定新颖的蛋白质信号。 H2O2的下游目标细胞核将被阐明和研究。质谱法将用于识别运输的蛋白质从叶绿体到核。将采用遗传方法来检查其在PCD中的作用。最后，将研究先天免疫期间叶绿体释放的机理，以确定它是否类似于哺乳动物凋亡期间的线粒体释放。了解PCD中不同细胞器的作用先天免疫将提供统一的机械基础，这是在对感染性病原体的反应。我们的模型系统的结果将广泛影响对了解细胞器到核交流会影响对传染病的先天免疫力。