Molecular Regulation of Exocytosis

胞吐作用的分子调控

• 批准号: 9757773
• 负责人: WEI GUO
• 金额: $ 33.7万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9757773
• 关键词: Address; Back; Binding; Biochemistry; Biophysics; Cell membrane; Cell physiology; Cells; Cellular biology; Complex; Core Assembly; Coupled; Cryoelectron Microscopy; Crystallography; Cytokinesis; Defect; Diabetes Mellitus; Disease; Docking; Dynamin; Embryonic Development; Endosomes; Epithelial; Epithelial Cells; Eukaryotic Cell; Exocytosis; Fluorescence; Foundations; Generations; Genetic Structures; Goals; Golgi Apparatus; Growth; Growth Factor; Hormones; In Vitro; Integrins; Light; Link; Lipids; Liposomes; Malignant Neoplasms; Mediating; Membrane Fusion; Modeling; Molecular; Monomeric GTP-Binding Proteins; Names; Organogenesis; Physiological Processes; Play; Polycystic Kidney Diseases; Positioning Attribute; Process; Proteins; Reagent; Recycling; Regulation; Regulation of Exocytosis; Renal carcinoma; Resolution; Role; SNAP receptor; Saccharomyces cerevisiae; Saccharomycetales; Secretory Vesicles; Signal Transduction; Signaling Molecule; Site; Sorting - Cell Movement; Structure; Synaptic Transmission; System; TFRC gene; Testing; Tubular formation; Tumor Cell Invasion; Vesicle; Work; catalyst; cell growth; cilium biogenesis; experimental study; fly; human disease; insight; interdisciplinary approach; malignant neurologic neoplasms; microscopic imaging; nervous system disorder; neurotransmission; polarized cell; protein complex; reconstitution; response; structural biology

Project Summary Exocytosis is important for the survival, growth and functions of all eukaryotic cells, and is centrally involved in many physiological processes ranging from neurotransmission to organogenesis. Exocytosis is mediated by transport, docking and fusion of secretory vesicles carrying cargos to the plasma membrane. The exocyst is an evolutionarily conserved octameric protein complex essential for exocytosis. Malfunction of the exocyst has been linked to diabetes, Autosomal Polycystic Kidney Diseases and cancer. We have recently solved the structure of the fully assembled exocyst complex by cryo-electron microscopy and identified two four-helix bundles, termed “CorEx”, that potentially mediate the core assembly of the exocyst complex. In this proposal, we will first study the molecular interactions and high-resolution structure of the CorEx taking a multipronged approach that combines biochemistry, biophysics, crystallography, and microscopic imaging. We will also determine the function of the exocyst complex in SNARE assembly and membrane fusion using in vitro reconstituted liposome systems. Finally, we will examine the functional implication of a newly identified interaction between the exocyst and EHD proteins, which function in the generation of tubular vesicular carriers from the endosomal compartments. We will further examine the regulation of the exocyst-EHD interaction by RalA, a small GTPase that controls endosomal recycling to the plasma membrane in response to growth factor signaling. Our work will not only help elucidate the mechanisms of exocytosis at the molecular level, but also shed light to a number of diseases such as diabetes and cancer.

项目摘要 胞吐作用对于所有真核细胞的生存，生长和功能都很重要，并且是 集中参与许多物理过程，从神经传递到 器官发生。胞吞作用是通过秘密蔬菜的运输，对接和融合来介导的 携带赤道到质膜。外囊肿是一种进化配置的八聚体 蛋白质复合物对于胞吐作用必不可少。外囊肿的故障已与糖尿病有关， 常染色体多囊性肾脏疾病和癌症。我们最近解决了 通过冷冻电子显微镜完全组装的胞囊复合物，并鉴定出两个四螺旋 捆绑包，称为“ corex”，可能介导外囊复合体的核心组装。在 该提案，我们将首先研究分子相互作用和高分辨率结构 Corex采用多收益的方法，结合了生物化学，生物物理学，晶体学， 和微观成像。我们还将确定在 使用体外重构的脂质体系统使用圈套组装和膜融合。最后，我们 将研究外囊肿和新近识别的相互作用的功能含义 EHD蛋白，该蛋白在内体的肾小管载体产生中起作用 车厢。我们将进一步研究Rala对胞外EHD相互作用的调节， 一个小的GTPase，该GTPase控制内体回收到质膜，以响应于质膜 生长因子信号传导。我们的工作不仅将有助于阐明胞吞作用的机制 在分子水平上，但也会使许多疾病（例如糖尿病和癌症）发明。