Role of the Tail Domain in Vinculin Function

尾部结构域在纽蛋白功能中的作用

• 批准号: 7933650
• 负责人: Sharon L Campbell
• 金额: $ 11.1万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-16 至 2011-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7933650
• 关键词: Actinin; Actins; Adherens Junction; Adhesions; Binding; Binding Sites; Biochemical; Biological; Biological Process; Body part; C-terminal; Cadherins; Cell Adhesion Molecules; Cell Line; Cell Shape; Cell Survival; Cells; Complex; Cytoskeletal Proteins; Cytoskeleton; Data; Defect; Embryo; Embryonic Development; Exhibits; Extracellular Matrix; F-Actin; Focal Adhesions; Goals; Head; Inositol; Integrins; Ligand Binding; Ligands; Lipids; Location; Mechanics; Mediating; Membrane; Modeling; Molecular; Molecular Conformation; Movement; Mus; N-terminal; Nature; PTK2 gene; Phenotype; Phosphatidylinositol 4,5-Diphosphate; Phospholipid Interaction; Phospholipids; Phosphorylation; Phosphorylation Site; Play; Polymers; Process; Property; Proteins; Regulation; Regulatory Element; Reporting; Role; Scaffolding Protein; Signal Transduction; Site; Structure; Tail; Talin; Testing; Tumor Suppressor Proteins; Variant; Vinculin; abstracting; base; cancer cell; cell motility; design; gene function; human disease; insight; migration; mutant; novel therapeutic intervention; numb protein; paxillin; receptor; scaffold; tumorigenic

DESCRIPTION (provided by applicant): This proposal is focused on vinculin, a cytoskeletal protein that is a prominent component of focal adhesions and adherens junctions. Vinculin is critical for cell migration, cell survival and embryogenesis and disruption of vinculin expression in mice results in an embryonic lethal phenotype. Vinculin functions as a mechanical linker between transmembrane integrin receptors and the actin cytoskeleton through association with cell adhesion molecules. Release of autoinhibitory head/tail interactions is believed to activate vinculin's function as a scaffold protein to facilitate assembly of multi-protein networks important for modulation of cytoskeleton structure and for downstream signaling. Although vinculin binds to a large number of cytoskeletal proteins, in many cases, we do not understand the nature of the interaction or functional significance. For example, the role of paxillin interactions and with the vinculin tail (Vt) domain in vinculin function is not known. In addition, several functional roles for acidic phospholipids (PL) have been proposed, including the involvement of acidic PLs in the activation process as well in regulating vinculin function once vinculin is activated. While recent studies suggest that vinculin/PL interactions promote uncoupling of adhesion sites from the actin cytoskeleton, our preliminary data indicates that these studies were conducted with mutants that are likely to multiple defects, including PL binding. Thus, while acidic PLs, specifically inositol 4, 5 bisphosphate, is believed to play an important role in vinculin regulation and function, its role remains unclear. Our efforts will focus on NMR, biophysical, biochemical and cell biological studies of vinculin, with the primarily focus on the role of ligand interactions with Vt. We will investigate the structural features of Vt, interactions of wt Vt with acidic PLs and paxillin, and explore the importance of these interactions in the biological function of vinculin. The specific aims of this proposal are to investigate the: 1) Regulation of vinculin through PL binding. 2) Structural basis for Vt/paxillin complex formation and the role of these interactions in controlling vinculin function. PUBLIC HEALTH RELEVANCE Vinculin is an essential protein involved controlling cell shape and motility, in part by anchoring actin polymers to the membrane. This function also extends to cancer cells, by regulating their movement and proliferation to other parts of the body. Hence, not too surprising, vinculin exhibits properties of a tumor suppressor protein. The activity of vinculin is controlled by regulating auto-inhibitory or `self' interactions between its head and tail domain. The goal of this effort is to characterize tail domain interactions with select proteins and lipids, to better understand how these binding interactions regulate vinculin activity and function. Results obtained from these studies may aid in developing novel therapeutic approaches for counteracting aberrant vinculin activity in human disease.

描述（由申请人提供）：该提案集中在Vinculin上，Vinculin是一种细胞骨架蛋白，是焦点粘附和粘附连接的重要组成部分。 vinculin对于小鼠的细胞迁移，细胞存活和胚胎发生以及小鼠表达的破坏至关重要，导致胚胎致死表型。通过与细胞粘附分子相关的跨膜整合素受体和肌动蛋白细胞骨架之间的机械连接器。据信自身抑制性头/尾相互作用的释放可以激活Vinculin作为脚手架蛋白的功能，以促进对调节细胞骨架结构和下游信号传导重要的多蛋白网络的组装。尽管Vinculin与大量细胞骨架蛋白结合，但在许多情况下，我们不了解相互作用或功能意义的性质。例如，尚不清楚Paxillin相互作用以及与vinculin尾巴（VT）结构域在Vinculin功能中的作用。此外，已经提出了酸性磷脂（PL）的几种功能作用，包括一旦激活Vinculin，酸性PL参与激活过程中，以及调节Vinculin功能。尽管最近的研究表明，源自肌动蛋白细胞骨架的粘附位点的粘附位点的解偶联，但我们的初步数据表明，这些研究是用可能具有多种缺陷（包括PL结合）的突变体进行的。因此，虽然酸性PL，特别是肌醇4、5双磷酸盐，据信在Vinculin调节和功能中起重要作用，但其作用尚不清楚。我们的努力将重点放在NMR，生物物理，生化和细胞生物学研究中，主要集中在配体与VT的作用上。我们将研究VT的结构特征，WT VT与酸性PLS和帕克西林的相互作用的相互作用，并探讨这些相互作用在这些相互作用中的重要性。该提案的具体目的是研究：1）通过PL结合对vinculin进行调节。 2）VT/paxillin复合物形成的结构基础以及这些相互作用在控制Vinculin功能中的作用。公共卫生相关性Vinculin是一种必不可少的蛋白质，涉及控制细胞形状和运动性，部分是通过将肌动蛋白聚合物固定在膜上。该功能还通过调节其运动和增殖到身体其他部位，从而扩展到癌细胞。因此，不足为奇的是，Vinculin具有抑制肿瘤蛋白的特性。 Vinculin的活性通过调节其头部和尾部域之间的自身抑制或“自我”相互作用来控制。这项工作的目的是表征与精选蛋白质和脂质的尾域相互作用，以更好地理解这些结合相互作用如何调节Vinculin的活性和功能。从这些研究中获得的结果可能有助于开发新型的治疗方法，以抵消人类疾病中异常的Vinculin活性。