Myo1c Participates in Podocyte Junction Formation Through Interaction with Neph1

Myo1c 通过与 Neph1 相互作用参与足细胞连接形成

• 批准号: 8444211
• 负责人: DEEPAK NIHALANI
• 金额: $ 3万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-05-15 至 2015-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8444211
• 关键词: ATP phosphohydrolase; Actins; Affect; Back; Belief; Binding; Biochemical; Biological Models; Calmodulin; Cell membrane; Cells; Clinical; Complex; Cytoplasm; Cytoskeleton; Data; Development; Diabetes Mellitus; Disease; Dissociation; End stage renal failure; Event; Family; Filtration; Foot Process; Functional disorder; Hypertension; In Vitro; Injury; Intercellular Junctions; Kidney; Knock-in Mouse; Knockout Mice; Lead; Location; Maintenance; Mediating; Membrane; Microscopy; Modeling; Molecular; Molecular Motors; Morbidity - disease rate; Motor; Mus; Mutate; Mutation; Myosin ATPase; Myosin Type I; Organelles; Outcome; Patients; Phosphorylation; Physiological; Play; Prevention; Process; Protein Binding; Protein translocation; Proteins; Proteinuria; Publishing; Recovery; Renal function; Renal glomerular disease; Research; Role; Signal Transduction; Signaling Protein; Site; Small Interfering RNA; Structure; System; Therapeutic; Tight Junctions; United States; base; cell type; glomerular function; improved; in vivo; member; molecular rearrangement; mortality; mouse model; mutant; nephrin; novel; podocyte; prevent; protein complex; public health relevance; response; restoration; slit diaphragm; tool

DESCRIPTION (provided by applicant): Glomerular diseases that lead to damaging changes in kidney filtration are an increasing cause of ESRD (end stage renal disease) nationwide. Unfortunately, the molecular mechanisms governing the development of ESRD remain poorly understood. Identification of podocyte proteins, including Neph1 and its associated protein complex, that are critical components of kidney filtration was a major advancement in understanding the organization of slit diaphragm. A number of recent studies, including ours, now demonstrate that dynamic interactions between Neph1 and its associated proteins including Grb2, ZO-1, Nephrin and Par3 regulates the actin cytoskeleton at the slit diaphragm. Data also suggest that Neph1 and its complex are frequently found in various sub cellular compartments away from the cell membrane following glomerular injury. Retargeting these proteins back to their membrane filtration slit location is likely to require an active molecular motor-based mechanism. We now have exciting results that identify a novel interaction of Neph1 with Myo1c, a member of the un-conventional Myosin family whose members are ATPase motor proteins that bind to actin and can generate force. Myo1c also has membrane binding and Calmodulin binding domains and has been shown to have a role in membrane cytoskeletal events in diverse cell types. We recently published an article demonstrating that glomerular injury results in mis-localization of the Neph1 complex leading to loss of cell junctions and proteinuria, whereas recovery from injury correlates with the Neph1 complex's return to the cell periphery (Wagner et al., JBC 2008). We believe that the interaction of Neph1 with Myo1c plays a critical role in regulating the organization of the Neph1 complex. In this study we propose to investigate the Neph1 and Myo1c interaction under in-vitro and in- vivo conditions. The specific aims proposed for this study are: 1) Define the physiologic and pathophysiologic organization of Myo1c in podocytes. 2) Determine the significance of Myo1c-Neph1 interaction in the assembly and translocation of Neph1 complex to the filtration slit in response to glomerular injury. 3) Determine the significance of Myo1c and its interaction with Neph1 in maintaining the glomerular function under in-vivo conditions. The results from this study will increase our understanding of how slit diaphragm proteins organize under both physiological and nonphysiological conditions resulting in new avenues of research aimed at improving clinical outcome following glomerular injury. PUBLIC HEALTH RELEVANCE: Glomerular diseases leading to end stage renal disease are major cause of kidney malfunction in United States. Our previous studies have shown that functional and biochemical changes in the proteins that are central to the maintenance of the kidney filtration system leads to the development of glomerular disorders. In this study we will determine the role of a novel protein Myo1c and identify novel targets for use in the development of novel therapies aimed at restoring the selective filtration function of kidneys during various glomerular disorders.

描述（由申请人提供）：导致肾脏过滤变化变化的肾小球疾病是全国ESRD（末期肾脏疾病）的越来越多的原因。不幸的是，涉及ESRD发展的分子机制仍然很少理解。肾脏过滤的关键成分（包括NEPH1及其相关蛋白复合物）的足细胞蛋白的鉴定是理解裂隙膜片组织的主要进步。现在的许多研究，包括我们的研究，现在表明NEPH1及其相关蛋白之间的动态相互作用在内，包括GRB2，ZO-1，Nephrin和Par3调节裂缝隔膜处的肌动蛋白细胞骨架。数据还表明，在肾小球损伤后，在远离细胞膜的各种亚细胞室中经常发现Neph1及其复合物。将这些蛋白质重新定位到其膜过滤缝隙位置可能需要有效的分子运动机制。现在，我们取得了令人兴奋的结果，可以确定Neph1与Myo1c的新型相互作用，Myo1c是非常规肌球蛋白家族的成员，其成员是与肌动蛋白结合并可以产生力的ATPase运动蛋白。 MyO1c还具有膜结合和钙调蛋白结合结构域，并且已被证明在各种细胞类型的膜细胞骨架事件中起作用。我们最近发表了一篇文章，表明肾小球损伤会导致NEPH1复合物的错误定位，从而导致细胞连接和蛋白尿的丧失，而损伤中的恢复与Neph1复合物的恢复相关（Wagner等，JBC 2008）。我们认为，Neph1与Myo1c的相互作用在调节NEPH1复合物的组织中起着至关重要的作用。在这项研究中，我们建议在体外和体内条件下研究NEPH1和MyO1c相互作用。这项研究提出的具体目的是：1）定义足细胞中MyO1C的生理和病理生理组织。 2）确定MyO1C-NEPH1相互作用在响应肾小球损伤的情况下，Neph1复合物的组装和易位到过滤缝隙的显着性。 3）确定MyO1c的显着性及其与NEPH1在维护条件下保持肾小球功能方面的相互作用。这项研究的结果将增加我们对在生理和非生理条件下如何组织隔膜蛋白如何组织的理解，从而导致新的研究途径旨在改善肾小球损伤后的临床结果。 公共卫生相关性：导致末期肾脏疾病的肾小球疾病是美国肾功能故障的主要原因。我们以前的研究表明，蛋白质的功能和生化变化是维持肾脏过滤系统的核心，导致肾小球疾病的发展。在这项研究中，我们将确定一种新型蛋白质myo1c的作用，并确定新型靶标在开发新型疗法中，旨在恢复各种肾小球疾病期间肾脏的选择性过滤功能。