Molecular mechanisms that regulate vesicle formation and transport

调节囊泡形成和运输的分子机制

• 批准号: 10333222
• 负责人: Anjon Audhya
• 金额: $ 54.92万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-02-01 至 2025-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10333222
• 关键词: Animals; Biochemistry; Biogenesis; Biological Models; Caenorhabditis elegans; Cell Differentiation process; Cell Proliferation; Cells; Cellular biology; Complex; Cytoplasm; Defect; Diabetes Mellitus; Diffusion; Disease; Endoplasmic Reticulum; Endosomes; Eukaryotic Cell; Future; Genes; Genetic; Goals; Golgi Apparatus; Homeostasis; Image; Immune System Diseases; Intervention; Intracellular Membranes; Laboratories; Lead; Link; Lipids; Location; Lysosomes; Malignant Neoplasms; Mediating; Membrane; Methodology; Molecular; Movement; Mutation; Nerve Degeneration; Neurodegenerative Disorders; Organelles; Pathway interactions; Play; Process; Protein Sortings; Proteins; Receptor Signaling; Regulation; Research; Resolution; Sorting - Cell Movement; System; Transmembrane Transport; Tumor Suppression; Vesicle; Work; insight; intracellular protein transport; protein degradation; protein transport; structural biology; therapeutic target; trafficking

PROJECT SUMMARY How the intracellular membrane system of eukaryotic cells is configured and maintained is a fundamental problem in cell biology. Deficiencies in this organization often lead to disease. The overarching goal of my laboratory is to define the molecular mechanisms that regulate membrane dynamics, including vesicle biogenesis, organelle trafficking, and protein sorting in the early secretory and endocytic pathways of metazoan cells. We aim to determine how normal membrane transport contributes to cellular homeostasis and understand the molecular basis for disease states that emerge when trafficking pathways are disrupted. Using a combination of model systems, structural biology, biochemistry, genetics, and high-resolution subcellular imaging, our studies focus on two essential trafficking pathways necessary for protein and lipid export from the endoplasmic reticulum (ER) and protein turnover within lysosomes via a multivesicular endosome (MVE) intermediate. Mutations in several factors that regulate these processes have been implicated in cancer, diabetes, immune dysfunction, and neurodegeneration. Thus, deciphering the fundamental principles underlying the regulation of ER export and MVE biogenesis should facilitate the future identification of therapeutic targets for disease intervention. One major focus of my research has been elucidating how the early secretory pathway is organized. Our findings revealed the existence of a conserved membrane interface, which links subdomains on the endoplasmic reticulum (ER) that produce COPII-coated transport carriers to juxtaposed ER-Golgi intermediate compartments (ERGIC). We identified Trk-fused gene (TFG) as a key constituent of this interface and have shown that its inhibition uncouples ER and ERGIC membranes and leads to the isotropic diffusion of COPII-coated carriers, reducing the efficiency of cargo secretion. My second research focus is aimed at understanding the mechanisms that direct the formation of MVEs, which bud intralumenal vesicles (ILVs) into their interior to sequester membrane-associated cargoes from the cytoplasm. Eventual fusion of MVEs with lysosomes results in the degradation of ILVs and their associated proteins, which plays a key role in tumor suppression by governing the capture and sequestration of signaling receptors. Using C. elegans, we have developed a new, highly simplified, and genetically tractable system to investigate how components of the endosomal sorting complex required for transport (ESCRT) machinery enables the movement of endocytosed cargo to MVEs and ILVs in the context of an intact, developing animal. Our future work will continue to capitalize on evolving methodologies to further establish how COPII-mediated transport and ESCRT-mediated MVE biogenesis are properly regulated. A better understanding of these processes will yield key insights into the homeostatic controls that sustain normal protein trafficking in the secretory and endocytic pathways during cell proliferation and differentiation.

项目摘要 真核细胞的细胞内膜系统如何配置和维护是基本的 细胞生物学问题。该组织的缺陷通常会导致疾病。我的总体目标 实验室要定义调节膜动力学的分子机制，包括囊泡 生物发生，细胞器贩运和蛋白质分类在后生的早期分泌和内吞途径中 细胞。我们旨在确定正常的膜运输如何对细胞稳态造成贡献并了解 疾病的分子基础指出，在贩运途径时出现。使用组合 模型系统，结构生物学，生物化学，遗传学和高分辨率亚细胞成像，我们的研究 专注于蛋白质和脂质从内质网所需的两种必需的运输途径 （ER）和蛋白质周转，通过多个内体（MVE）中间体内部溶酶体内部。突变 调节这些过程的几个因素与癌症，糖尿病，免疫功能障碍有关， 和神经变性。因此，解释了ER出口监管的基本原则 MVE生物发生应促进对疾病干预的治疗靶标的未来鉴定。一 我的研究的主要重点是阐明了早期分泌途径的组织方式。我们的发现 揭示了存在保守的膜界面的存在，该膜界面连接了内质上的子域 网状（ER），生产涂层的传输载体与并置的ER-Golgi中间隔间 （ERGIC）。我们将TRK融合基因（TFG）识别为该界面的关键组成部分，并表明它 抑制作用的ER和ERGIC膜，并导致Copii涂层载体的各向同性扩散， 降低货物分泌的效率。我的第二个研究重点旨在了解机制 指导MVE的形成，将其芽内囊泡（ILV）芽到其内部到隔离 来自细胞质的膜相关货物。 MVE与溶酶体的最终融合会导致 ILV及其相关蛋白的降解，该蛋白在肿瘤抑制中起着关键作用 捕获和隔离信号受体。使用秀丽隐杆线虫，我们开发了一种新的，高度简化的， 和遗传上可牵引的系统，以研究内体分类复合物的组件如何需要 运输（ESCRT）机械使内吞货物的移动到MVE和ILV。 完整的动物。我们未来的工作将继续利用不断发展的方法，以进一步 确定如何适当调节COPII介导的转运和ESCRT介导的MVE生物发生。更好 了解这些过程将产生对维持正常蛋白质的稳态控制的关键见解 在细胞增殖和分化过程中，贩运分泌和内吞途径。