Regulation of Syntrophin Function

肌营养不良蛋白功能的调节

• 批准号: 7735467
• 负责人: STANLEY C FROEHNER
• 金额: $ 34.58万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-04-01 至 2014-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7735467
• 关键词: Address; Amino Acids; Arrhythmia; Beta Cell; Binding; Binding Proteins; Binding Sites; Biochemical; Brain; Brain Edema; C-terminal; Cardiac; Cell Culture Techniques; Cell membrane; Cells; Characteristics; Chimera organism; Co-Immunoprecipitations; Complex; Cyclic GMP-Dependent Protein Kinases; Cytoplasm; Diabetes Mellitus; Disease; Dissociation; Duchenne muscular dystrophy; Dystrophin; Epilepsy; Epitopes; Exercise; Exhibits; Family; Family member; Fatigue; Figs - dietary; G-Protein-Coupled Receptors; Goals; Health; IA-2 protein; Immunofluorescence Immunologic; In Situ; In Vitro; Ion Channel; Ions; Ligands; Link; Lipids; Measurement; Measures; Membrane; Methods; Modification; Molecular; Mus; Muscle; Muscle function; Muscular Dystrophies; Mutant Strains Mice; Mutate; Mutation; Myopathy; Names; Nitric Oxide Synthase Type I; PH Domain; Phosphatidylinositols; Phosphorylation; Phosphorylation Site; Phosphotransferases; Physiological; Potassium; Predisposition; Process; Protein Binding; Protein Dephosphorylation; Protein Family; Protein Isoforms; Proteins; Protocols documentation; Regulation; Reporting; Role; SHPS-1 protein; Sarcolemma; Sarcoplasmic Reticulum; Scaffolding Protein; Secretory Vesicles; Signal Transduction; Signaling Protein; Skeletal Muscle; Sodium; Specificity; Staging; Stroke; Structure; Tail; Testing; Transgenic Mice; Transgenic Organisms; Trauma; Utrophin; adapter protein; aquaporin 4; base; cell type; dystrobrevin; human disease; in vivo; member; mutant; platelet protein P47; prevent; protein complex; public health relevance; research study; scaffold; syntrophin; syntrophin alpha1; water channel

DESCRIPTION (provided by applicant): The syntrophins are a family of adapter proteins that bind numerous signaling proteins and link them to the dystrophin protein complex (DPC). All five syntrophins share a common domain structure: a PDZ domain (which binds signaling proteins), two PH domains and a C-terminal region unique to the syntrophins (the SU domain). Syntrophin-associated signaling proteins include ion and water channels, neuronal nitric oxide synthase (nNOS), protein and lipid kinases, transporters and G-protein coupled receptors. This proposal will focus on the regulation of nNOS and aquaporin-4 (AQP4) interaction with alpha-syntrophin in skeletal muscle. Recent studies have shown that nNOS is critically important to muscle function and health. Loss of nNOS increases the susceptibility of muscle to exercise-induced fatigue, perhaps due in part to defective vasoregulation. The goal of this proposal is to determine the molecular mechanisms that regulate the interaction of alpha-syntrophin with dystrophin (via the PH2-SU domains) and with nNOS and AQP4 (via the PH1-PDZ domains). Based on recent studies showing that phosphorylation/dephosphorylation of beta2-syntrophin regulates interaction with a key PDZ ligand, we propose a comprehensive approach to identify phosphorylation sites on alpha- syntrophin and determine if phosphorylation status regulates syntrophin binding to dystrophin and to its PDZ ligands. Mutants of alpha-syntrophin that mimic or prevent phosphorylation will be analyzed for interaction with dystrophin and nNOS biochemically and in cell culture. Ultimately, mutated alpha-syntrophins will be studied in vivo in transgenic mice. These studies include nNOS targeting and physiological function of skeletal muscle. New transgenic results demonstrate that the PH1 domain is important in the association of nNOS with the DPC and the sarcolemma. We will examine the role of phosphatidylinositol lipids and PH1 binding proteins in this regulatory mechanism. The DPC is capable of binding four syntrophins, thus forming a scaffold for functionally interdependent signaling proteins. Deciphering the role of phosphorylation and phosphatidylinositol binding in this process is essential to understanding the signaling function of the DPC and its role in muscle diseases. PUBLIC HEALTH RELEVANCE: Syntrophins are a family of proteins that are part of the dystrophin complex. Abnormalities in the dystrophin complex cause many forms of muscular dystrophy, including Duchenne MD. Syntrophins are also involved in many other human diseases, including cardiac arrhythmia, brain edema cause by trauma or stroke, epilepsy, and diabetes. Our long term goal is to understand the function of the syntrophins in cell signaling and how abnormalities cause disease.

描述（由申请人提供）：综合蛋白是结合大量信号蛋白并将其链接到肌营养不良蛋白蛋白复合物（DPC）的衔接蛋白家族。所有五个综合症都具有共同的结构结构：PDZ结构域（结合信号蛋白），两个pH结构域和一个独特的综合症（SU结构域）的C末端区域。综合素相关的信号蛋白包括离子和水通道，神经元氧化物合酶（NNOS），蛋白质和脂质激酶，转运蛋白和G蛋白偶联受体。该提案将重点介绍NNOS和Aquaporin-4（AQP4）与骨骼肌中α-促链蛋白的相互作用。最近的研究表明，NNOS对肌肉功能和健康至关重要。 NNOS的丧失增加了肌肉对运动引起的疲劳的敏感性，这可能部分归因于血管调节缺陷。该提案的目的是确定调节α-链球菌与肌营养不良蛋白（通过pH2-SU结构域）以及NNOS和AQP4（通过pH1-PDZ结构域）相互作用的分子机制。基于最近的研究表明，β2-促链蛋白的磷酸化/去磷酸化调节与关键PDZ配体的相互作用，我们提出了一种综合方法来鉴定α-综合蛋白上的磷酸化位点并确定磷酸化状态是否调节磷酸化的状态是否可以调节与pdstrophin and pdz ligands cyntrophin结合。将分析模仿或预防磷酸化的α-链球菌突变体，以与肌营养不良蛋白和NNOS生化和细胞培养中的相互作用。最终，将在转基因小鼠的体内研究突变的α-伴侣蛋白。这些研究包括NNOS靶向和骨骼肌的生理功能。新的转基因结果表明，PH1结构域在NNOS与DPC和肌膜的关联中很重要。我们将研究磷脂酰肌醇脂质和PH1结合蛋白在该调节机制中的作用。 DPC能够结合四种综合素，从而形成了功能相互依存的信号蛋白的支架。解读磷酸化和磷脂酰肌醇在此过程中的作用对于理解DPC的信号传导及其在肌肉疾病中的作用至关重要。公共卫生相关性：综合蛋白是蛋白质家族，是肌营养不良蛋白络合物的一部分。肌营养不良蛋白复合物的异常引起许多形式的肌肉营养不良，包括Duchenne MD。综合症还参与了许多其他人类疾病，包括心律不齐，脑水肿导致创伤或中风，癫痫和糖尿病。我们的长期目标是了解综合症在细胞信号传导中的功能以及异常如何引起疾病。