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

• 批准号: 7887764
• 负责人: Steven H Caplan
• 金额: $ 28.87万
• 依托单位: UNIVERSITY OF NEBRASKA MEDICAL CENTER
• 依托单位国家: 美国
• 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/7887764
• 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; 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

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）：控制受体定位到质膜的核心是正常细胞功能的核心，并且失调是诸如动脉粥样硬化，糖尿病和癌症等疾病的根本原因。质膜上的受体水平取决于内在化的速率和回收回到细胞表面。我们和其他人最近将含有蛋白质EHD1的新型EPS15同源性（EH）域确定为内吞回收途径的关键成分。 EHD介导的功能的生理重要性已清楚地证明，因为EHD1功能的丧失导致许多关键受体的回收受损。该项目的长期目标是了解控制细胞内运输和蛋白质运输到质膜的基本机制，重点是理解EHD结构影响其功能的模式。该提案的中心假设是，EHD1（EH-1）EH域的静电表面电荷及其C末端EHD旁系同源物负责与含NPF蛋白质伴侣和磷酸磷酸磷酸固醇的相互作用的选择性，并且这些相互作用对于这些相互作用对于内皮细胞转运的调节很重要。我们基于强大的初步数据为假设提供了令人信服的证据，即EH-1与含有NPF基序的蛋白质选择性相互作用，然后是一系列带负电荷的残基。此外，我们的新初步数据还通过证明EH-1能够与磷脂酰肌醇部分直接相互作用来反映EHD/磷酸固醇相互作用的功能重要性，并且需要这种相互作用来允许将EHD1定位到肾小管和vesicular膜结构。 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.从这项研究中获得的知识将提供有关C末端EHD蛋白与内体膜并协调回收控制的模式的关键新信息。这将导致对调节受体回收的内吞机制的显着增强，并将对健康和疾病产生重要影响。 公共卫生相关性：控制受体定位到质膜是正常细胞功能的核心，失调是诸如动脉粥样硬化，糖尿病和癌症等多样性疾病的根本原因。进行该建议将获得的知识将导致对调节受体回收的内吞机制的明显增强，并将对健康和疾病产生重要影响。