Regulation of EHD protein function by molecular partner interactions

通过分子伴侣相互作用调节 EHD 蛋白功能

基本信息

批准号：
8274823
负责人：
Steven H Caplan
金额：
$ 28.59万
依托单位：
UNIVERSITY OF NEBRASKA MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-06-01 至 2014-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8274823
关键词：
Address Area Asparagine Atherosclerosis Back Binding Biochemical Biological Assay C-terminal Carrier Proteins Cell membrane Cell physiology Cell surface Cells Charge Data Development Diabetes Mellitus Disease Early Endosome Electrostatics Epithelial Event Familial Hypercholesterolemia Goals Growth Factor Receptors Health Knowledge Lead Low Density Lipoprotein Receptor Malignant Neoplasms Mediating Membrane Membrane Lipids Molecular N-terminal NMR Spectroscopy Normal Cell Pancreatic carcinoma Pathway interactions Phenylalanine Phosphatidylinositol 4,5-Diphosphate Phosphatidylinositols Physiological Proline Protein Family Protein Region Proteins Recycling Regulation Research Solutions Structure Surface Techniques Testing Tubular formation Work base genetic regulatory protein innovation insight malignant breast neoplasm novel paralogous gene phosphatidylinositol 4-phosphate protein function public health relevance rab4 GTP-Binding Proteins receptor receptor recycling trafficking tumor

项目摘要

DESCRIPTION (provided by applicant): Control of receptor localization to the plasma membrane is central to normal cell function, and dysregulation is the underlying cause for diseases as diverse as atherosclerosis, diabetes and cancer. Receptor levels on the plasma membrane are dependent upon the rates of internalization and recycling back to the cell surface. We and others have recently identified a novel Eps15 homology (EH)-domain containing protein, EHD1, as a critical component of the endocytic recycling pathway. The physiologic importance of EHD-mediated function has been clearly demonstrated, as loss of EHD1 function leads to impaired recycling of many critical receptors. The long- term goals of this project are to understand the fundamental mechanisms controlling intracellular trafficking and transport of proteins to the plasma membrane, with emphasis on understanding the mode by which EHD structure impacts its function. The central hypothesis of this proposal is that the electrostatic surface charge of the EH-domain of EHD1 (EH-1) and its C-terminal EHD paralogs is responsible for the selectivity of interactions with NPF-containing protein partners and phosphoinositides, and that these interactions are important for the regulation of endocytic transport. We provide compelling evidence for our hypothesis based on our strong preliminary data that EH-1 selectively interacts with proteins containing NPF motifs followed by a cluster of negatively charged residues. In addition, our new preliminary data also reflect the functional importance of the EHD/phosphoinositide interactions by demonstrating that EH-1 is capable of interacting directly with phosphatidylinositol moieties, and that this interaction is required to allow localization of EHD1 to tubular and vesicular membrane structures. Our Specific Aims for the proposal are: 1) To identify the molecular and structural basis for the selectivity of C-terminal EH-domains for specific NPF-containing proteins, and 2) To elucidate the specific phosphoinositide(s) that are enriched/comprise EHD tubular membranes and determine the significance of EHD/phosphoinositide binding in the regulation of endocytic trafficking. The knowledge to be obtained from this study will provide critical new information on the mode by which the C-terminal EHD proteins associate with endosomal membranes and coordinate control of recycling. This will lead to a significantly enhanced understanding of the endocytic mechanisms that regulate receptor recycling, and will have an important bearing on health and disease. PUBLIC HEALTH RELEVANCE: Control of receptor localization to the plasma membrane is central to normal cell function, and dysregulation is the underlying cause for diseases as diverse as atherosclerosis, diabetes and cancer. The knowledge to be gained from undertaking this proposal will lead to a significantly enhanced understanding of the endocytic mechanisms that regulate receptor recycling, and will have an important bearing on health and disease.

描述（由申请人提供）：对质膜受体定位的控制是正常细胞功能的核心，而失调是动脉粥样硬化、糖尿病和癌症等多种疾病的根本原因。质膜上的受体水平取决于内化和再循环回细胞表面的速率。我们和其他人最近发现了一种新的包含 Eps15 同源 (EH) 结构域的蛋白质 EHD1，它是内吞循环途径的关键组成部分。 EHD 介导的功能的生理重要性已得到明确证明，因为 EHD1 功能的丧失会导致许多关键受体的再循环受损。该项目的长期目标是了解控制细胞内蛋白质运输和运输到质膜的基本机制，重点是了解 EHD 结构影响其功能的模式。该提议的中心假设是 EHD1 (EH-1) 的 EH 结构域及其 C 端 EHD 旁系同源物的静电表面电荷负责与含 NPF 的蛋白质伴侣和磷酸肌醇相互作用的选择性，并且这些相互作用对于内吞运输的调节很重要。我们基于强有力的初步数据为我们的假设提供了令人信服的证据，即 EH-1 选择性地与含有 NPF 基序的蛋白质相互作用，后跟一组带负电的残基。此外，我们的新初步数据还反映了 EHD/磷酸肌醇相互作用的功能重要性，证明 EH-1 能够直接与磷脂酰肌醇部分相互作用，并且这种相互作用是允许 EHD1 定位到管状和囊泡膜结构所必需的。我们该提案的具体目标是：1) 确定 C 端 EH 结构域对特定含 NPF 的蛋白质的选择性的分子和结构基础，以及 2) 阐明富集/包含的特定磷酸肌醇EHD 肾小管膜并确定 EHD/磷酸肌醇结合在内吞运输调节中的重要性。从这项研究中获得的知识将为 C 端 EHD 蛋白与内体膜结合并协调回收控制的模式提供重要的新信息。这将显着增强对调节受体再循环的内吞机制的理解，并对健康和疾病产生重要影响。公共健康相关性：对质膜受体定位的控制对于正常细胞功能至关重要，而失调是动脉粥样硬化、糖尿病和癌症等多种疾病的根本原因。从实施该提案中获得的知识将显着增强对调节受体再循环的内吞机制的理解，并将对健康和疾病产生重要影响。