Phosphatidylinositol 3-Phosphate in the Regulation of Autophagic Membrane Remodeling

磷脂酰肌醇 3-磷酸在自噬膜重塑调节中的作用

• 批准号: 10506784
• 负责人: Ting-Sung Hsieh
• 金额: $ 10万
• 依托单位: UT SOUTHWESTERN MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-07 至 2024-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10506784
• 关键词: 1-Phosphatidylinositol 3-Kinase; Acute; Address; Advisory Committees; Architecture; Automobile Driving; Autophagocytosis; Autophagosome; Award; Binding; Biochemical; Biogenesis; Biological; Biological Assay; Biophysics; Cell physiology; Cells; Chemicals; Coupled; Data; Diabetes Mellitus; Diffusion; Disease; Disease Outcome; Endoplasmic Reticulum; Ensure; Environment; Event; Functional disorder; Future; Generations; Genetic; Goals; In Vitro; Intracellular Membranes; Lead; Legionella; Legionella pneumophila; Link; Lipids; Lysosomes; Malignant Neoplasms; Mediating; Medical center; Membrane; Membrane Biology; Methods; Modeling; Molecular; N-terminal; Nerve Degeneration; Organelles; Outcome; Pathologic Processes; Pathway interactions; Pattern; Phase; Phosphatidylinositols; Phosphoric Monoester Hydrolases; Phosphotransferases; Physiological Processes; Play; Proteins; Reaction; Regulation; Research; Research Personnel; Research Training; Role; Scientist; Site; Structure; System; Testing; Theoretical model; Therapeutic; Training; Tubular formation; Vesicle; Vps34 Phosphatidylinositol 3 Kinase; biophysical techniques; career; career development; chronic infection; human disease; in silico; innovation; live cell imaging; membrane model; novel therapeutic intervention; optogenetics; pathogen; pathogenic bacteria; phosphatidylinositol 3-phosphate; phosphatidylinositol-3-phosphatase; protein degradation; quantitative imaging; reconstitution; recruit; research and development; skills; spatiotemporal; success; tool

PROJECT SUMMARY/ABSTRACT Autophagy is a fundamental cellular process mediating lysosome-dependent degradation of proteins, organelles, and intracellular pathogens. Dysfunction of autophagy is associated with many diseases, including cancer, neurodegeneration, diabetes, and chronic infections. Better elucidation of the molecular mechanisms for autophagy may inspire new therapeutic approaches to these diseases. Autophagy initiation occurs at endoplasmic reticulum (ER) subdomains enriched with phosphatidylinositol 3-phosphate (PI3P). Autophagy is blocked when depleting or inactivating VPS34, the phosphatidylinositol (PI) 3-kinase responsible for PI3P synthesis during autophagy. Nevertheless, how PI3P contributes to membrane remodeling events crucial for autophagosome biogenesis remains elusive. Much is also unknown about how PI3P synthesis and turnover are orchestrated at autophagy initiation sites. Dr. Hsieh recently discovered that the Legionella PI 3-kinase MavQ generates PI3P on the ER and drives membrane remodeling. He also found that MavQ is coupled with the Legionella PI 3-phosphatase SidP to spatiotemporally modulate PI3P levels at ER subdomains, inducing vesicle/tubule budding. The striking similarity between this pathological process and autophagy initiation prompts Dr. Hsieh to dissect the molecular and physical factors that PI3P brings for autophagic membrane remodeling. Moreover, the current technical hurdles in tackling this question can mostly be cleared by using MavQ and SidP as tools. In Dr. Hsieh’s proposed research, Aim 1 will develop optogenetic methods to control PI3P generation in the cell and determine how PI3P regulates autophagic membrane remodeling using live-cell imaging and systematic genetic perturbations. Aim 2 will combine in vitro biophysical assays, optogenetic control, and quantitative imaging to elucidate how PI3P domain formation leads to membrane remodeling. Aim 3 will reconstitute a reaction-diffusion system in vitro and use this system to determine how PI 3-kinases and phosphatases drive the formation of PI3P-enriched membrane subdomains. Dr. Hsieh’s career goal is to become a leader in cell biophysics and membrane biology, focusing on physiological and pathological processes involving membrane remodeling. Training during the award period will prepare him to lead an independent research group using cell biological, biochemical, and biophysical approaches to understand the mechanistic basis of autophagic membrane remodeling. UT Southwestern Medical Center provides an excellent environment to aid Dr. Hsieh’s proposed research and career development. Dr. Hsieh has also set up an advisory committee consisting of leading scientists with complementary research expertise. Under their guidance, Dr. Hsieh will receive the necessary research training, such as preparing and using various model membrane systems, and further develop professional skills during the award period. These will significantly facilitate Dr. Hsieh's transition into an independent investigator and ensure his future success.

项目摘要/摘要 自噬是一种基本的细胞过程，介导蛋白质，细胞器， 和细胞内病原体。自噬功能障碍与包括癌症在内的许多疾病有关 神经变性，糖尿病和慢性感染。更好地阐明分子机制的 自噬可能会激发这些疾病的新治疗方法。自噬倡议发生在 富含磷脂酰肌醇3-磷酸（PI3P）的内质网（ER）亚域。自噬是 磷脂酰肌醇（PI）3-激酶时，耗尽或灭活VPS34时被阻塞。 自噬过程中的合成。然而，PI3P如何促进膜重塑事件至关重要 自噬体生物发生仍然难以捉摸。关于PI3P的合成和周转方式，也未知很多 在自噬计划网站上精心策划。 Hsieh博士最近发现，pi 3-激酶MAVQ 在ER上生成PI3P并驱动膜重塑。他还发现MAVQ与 Pi 3-磷酸酶SIDP到ER子域的时空调节PI3P水平，诱导的PI3P水平 囊泡/小管芽。这种病理过程与自噬开始之间的惊人相似性 提示HSIEH博士解剖PI3P为自噬膜带来的分子和物理因素 重塑。此外，目前解决此问题的技术障碍可以通过使用 MAVQ和SIDP作为工具。在Hsieh博士提出的研究中，AIM 1将开发用于控制的光遗传学方法 PI3P在细胞中生成并确定PI3P如何使用活细胞调节自噬膜重塑 成像和系统的遗传扰动。 AIM 2将结合体外生物物理测定，光遗传学 对照和定量成像，以阐明PI3P结构域的形成如何导致膜重塑。目的 3将在体外重建一个反应扩散系统，并使用该系统来确定PI 3-激酶和 磷酸酶驱动富含PI3P的膜亚域的形成。 Hsieh博士的职业目标是成为 细胞生物物理学和膜生物学领域的领导者，专注于物理和病理过程 涉及膜重塑。奖励期间的培训将使他为领导独立 研究小组使用细胞生物学，生化和生物物理方法来了解机械 自噬膜重塑的基础。 UT西南医疗中心提供了一个绝佳的环境 帮助Hsieh博士提议的研究和职业发展。 Hsieh博士还成立了咨询委员会 由具有完整研究专业知识的主要科学家组成。在他们的指导下，Hsieh博士将 接受必要的研究培训，例如准备和使用各种模型膜系统，以及 在奖励期间进一步发展专业技能。这些将大大促进Hsieh博士的 过渡到独立的调查员，并确保他未来的成功。