Molecular Mechanisms Controlling Endocytic Recycling

控制内吞再循环的分子机制

• 批准号: 7935858
• 负责人: Steven H Caplan
• 金额: $ 21.23万
• 依托单位: UNIVERSITY OF NEBRASKA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-30 至 2011-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7935858
• 关键词: AMPA Receptors; Address; Atherosclerosis; Back; Binding; Biochemical; Biological Assay; Carrier Proteins; Cell Line; Cell membrane; Cell physiology; Cell surface; Cholesterol Homeostasis; Cystic Fibrosis; Data; Development; Diabetes Mellitus; Disease; Early Endosome; Engineering; Epithelial; Event; Familial Hypercholesterolemia; Family; Fibroblasts; Flow Cytometry; Gap Junctions; Glucose Transporter; Goals; Growth Factor Receptors; Hand; Health; Heart Diseases; Insulin; Knock-in Mouse; Knockout Mice; Knowledge; Laboratories; Lead; Link; Long-Term Potentiation; Low Density Lipoprotein Receptor; Major Histocompatibility Complex; Malignant Neoplasms; Mammalian Cell; Mediating; Microscopic; Molecular; Normal Cell; Nutrient; Pancreatic carcinoma; Pathway interactions; Play; Protein Family; Proteins; Publishing; RNA Interference; Recycling; Regulation; Research; Research Personnel; Role; Route; SNAP receptor; Series; Signal Transduction; Silent Mutation; Staging; Synapses; Technology; Testing; Transgenic Organisms; Vesicle; Work; base; glucose transport; innovation; knock-down; malignant breast neoplasm; novel; paralogous gene; programs; protein function; protein transport; rab GTP-Binding Proteins; rab11 protein; rab4 GTP-Binding Proteins; receptor; receptor recycling; success; trafficking; tumor; uptake

DESCRIPTION (provided by applicant): Endocytic recycling is essential for the control of receptors on the plasma membrane in mammalian cells. Consequently, recycling impacts health by regulating crucial cellular events such as signal transduction and proliferation, cholesterol homeostasis, nutrient uptake, and insulin-dependent glucose transport. Thus, understanding the regulation of endocytic events is critical for a wide range of diseases, including malignancies, heart disease and diabetes. Endocytic transport and recycling are controlled by a number of small Rab GTP-binding proteins. Recently, a non-Rab protein called EHD1 has been ascribed a role in regulating recycling at the recycling compartment. However, the mode by which EHD1 coordinates its regulatory activity with Rab-family proteins is not understood. A biochemical approach has identified the divalent Rab4/Rab5 effector prtoein, Rabenosyn-5, as a binding partner for EHD1, and defined a role for it in recycling at the early endosome. The critical task at hand is to understand how trafficking events at the early endosome are linked to those at the recycling compartment, particularly what regulates transport and fusion of early endosome-derived vesicles with the recycling compartment. The first aim will focus on identifying the mechanisms by which proteins are transported from early endosomes to the endocytic recycling compartment, en route to the plasma membrane. The working hypothesis is that the interaction between EHD1 and Rabenosyn-5 is critical for transport of internalized proteins from early endosomes to the recycling compartment. The second aim is based on new data elucidating a physical connection between EHD proteins and a Rab11 effector protein, and proposes to determine the mechanisms by which EHD proteins coordinate endocytic recycling and transport with Rab11 and SNARE proteins. The working hypothesis is that EHD proteins coordinate transport steps with Rab11 and its effectors, and that the SNARE proteins Syntaxin13 and SNAP29 play a critical role in fusion of early endosome-derived vesicles at the recycling compartment. These aims will be accomplished using novel fibroblasts from EHD1-knock-out mice, RNAi- based 'knock-down/knock-in' strategy, and a series of biochemical, flow cytometry and microscopic assays. These studies will significantly enhance our fundamental understanding of the mechanisms regulating recycling and have an important bearing on diseases as diverse as cancer and atherosclerosis and diabetes.

描述（由申请人提供）：内吞回收对于控制哺乳动物细胞中质膜上的受体至关重要。因此，回收利用通过调节关键的细胞事件（例如信号转导和增殖，胆固醇稳态，营养摄取和胰岛素依赖性葡萄糖转运）来影响健康。因此，了解内吞事件的调节对于包括恶性肿瘤，心脏病和糖尿病在内的多种疾病至关重要。内吞运输和回收由许多小的RAB GTP结合蛋白控制。最近，一种称为EHD1的非兔蛋白在调节回收室的回收中起了作用。但是，尚不清楚EHD1与Rab-Family蛋白协调其调节活性的模式。一种生化方法已将二价rab4/rab5效应子prtoein，rabenosyn-5确定为EHD1的结合伴侣，并定义了它在早期内体回收中的作用。手头的关键任务是了解早期内体的贩运事件与回收室中的贩运事件是如何联系的，尤其是在回收隔间的早期内体衍生囊泡的运输和融合中。第一个目的将集中在识别蛋白质从早期内体转移到内吞回收室的机制，该机制是在到质膜的过程中。工作假设是，EHD1和Rabenosyn-5之间的相互作用对于将内部化蛋白从早期内体转移到回收室的运输至关重要。第二个目的是基于阐明EHD蛋白与RAB11效应蛋白之间物理连接的新数据，并提议确定EHD蛋白与RAB11和SNARE蛋白的内吞回收和转运的机制。工作假设是EHD蛋白与RAB11及其效应子协调运输步骤，而SNARE蛋白质语法和SNAP29在回收室中早期内体衍生的囊泡的融合中起关键作用。这些目标将使用来自EHD1敲出小鼠，基于RNAi的“敲门/敲门”策略以及一系列生化，流式细胞术和微观测定的新型成纤维细胞来实现。这些研究将显着增强我们对调节回收的机制的基本理解，并对像癌症，动脉粥样硬化和糖尿病等多样化有关。