Fibronectin and Platelet Function

纤连蛋白和血小板功能

• 批准号: 7819162
• 负责人: DEANE Fremont MOSHER
• 金额: $ 0.74万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-06-01 至 2009-10-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7819162
• 关键词: Accounting; Adhesions; Adhesives; Biochemical; Blood Platelets; Cell Surface Proteins; Cell surface; Collagen; Development; Factor XIIIa; Fibrin; Fibrinogen; Fibroblasts; Fibronectins; In Vitro; Integrins; Laminin; Ligands; Mediating; Membrane Proteins; Methods; Microscopic; Molecular; Mutagenesis; N-terminal; Plasma; Proteins; Proteomics; Signal Pathway; Site; Stretching; Structure; Surface; System; Thrombus; VWF gene; Vitronectin; crosslink; tool; von Willebrand Factor

DESCRIPTION (provided by applicant): The aims of this resubmitted competitive renewal follow on results demonstrating that the ability of adherent platelets to assemble plasma fibronectin is determined by the ligands that mediate platelet adhesion. Thus, platelets adherent of fibrinogen, vitronectin, or von Willebrand factor are suppressed in their ability to assemble fibronectin whereas platelets adherent to fibrin, laminin, collagen, or fibronectin itself assemble fibronectin robustly. Further, assembly of fibronectin by platelets in an ex vivo flow system is a strong determinant of the extent of platelet thrombus formation on matrices of fibrin or collagen. The hypotheses are (i) platelet integrins and other cell surface proteins recognize critical features of adhesive ligands, initiating subtly different signaling pathways that support or suppress subsequent assembly of fibronectin by adherent platelets; (ii) as yet unappreciated differences in the microscopic and biochemical consequences of platelet adhesion correlate with the ability of adherent platelets to assemble fibronectin; and (iii) the N- terminal portion of fibronectin interacts specifically with unstructured stretches of certain proteins, among which are the cell surface molecules on adherent platelets and fibroblasts that drive fibronectin assembly. Specific aims are to: 1. Identify features of fibronectin, fibrinogen/fibrin, vitronectin, and von Willebrand factor that account for their supportive or suppressive activity. 2. Characterize differences other than ability to assemble fibronectin that distinguish platelets adherent to supportive and suppressive ligands. 3. Discover the molecular features of fibronectin assembly sites present on adherent assembly- competent platelets and absent on adherent assembly-incompetent platelets. Methods to accomplish these aims include in vitro mutagenesis to dissect the structure/function of the supportive and suppressive adhesive ligands, microscopic and proteomic characterization of assembly- competent and assembly-incompetent adherent platelets, utilization of a reversible cross-linking strategy to identify the platelet surface proteins that interact with supportive and suppressive adhesive ligands, and development of activated blood coagulation Factor XIII as a tool to identify the platelet surface molecules that initiate fibronectin assembly.

描述（由申请人提供）：本次重新提交的竞争性更新的目的在于证明粘附血小板组装血浆纤连蛋白的能力是由介导血小板粘附的配体决定的。因此，粘附纤维蛋白原、玻连蛋白或血管性血友病因子的血小板组装纤连蛋白的能力受到抑制，而粘附到纤维蛋白、层粘连蛋白、胶原或纤连蛋白本身的血小板则牢固地组装纤连蛋白。此外，在离体流动系统中血小板对纤连蛋白的组装是纤维蛋白或胶原基质上血小板血栓形成程度的重要决定因素。这些假设是：（i）血小板整合素和其他细胞表面蛋白识别粘附配体的关键特征，启动细微不同的信号通路，支持或抑制粘附血小板随后组装纤连蛋白； (ii) 血小板粘附的微观和生化后果与粘附血小板组装纤连蛋白的能力相关的差异尚未得到认识； (iii)纤连蛋白的N端部分与某些蛋白质的非结构化片段特异性相互作用，其中包括粘附血小板和成纤维细胞上驱动纤连蛋白组装的细胞表面分子。具体目标是： 1. 确定纤连蛋白、纤维蛋白原/纤维蛋白、玻连蛋白和冯维勒布兰德因子的特征，以解释其支持或抑制活性。 2. 除了组装纤连蛋白的能力之外，表征差异，以区分粘附于支持性配体和抑制性配体的血小板。 3. 发现具有粘附组装能力的血小板上存在的纤连蛋白组装位点以及不具有粘附组装能力的血小板上不存在的纤连蛋白组装位点的分子特征。实现这些目标的方法包括体外诱变以剖析支持性和抑制性粘附配体的结构/功能、组装能力和组装不能力粘附血小板的微观和蛋白质组学表征、利用可逆交联策略来识别血小板与支持性和抑制性粘附配体相互作用的表面蛋白，以及开发活化的凝血因子 XIII 作为识别启动纤连蛋白组装的血小板表面分子的工具。