UROKINASE KRINGLE-MEDIATED VASCULAR REMODELING

尿激酶Kringle介导的血管重塑

• 批准号: 6499500
• 负责人: Douglas Brock Cines
• 金额: $ 4.03万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-02-01 至 2004-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6499500
• 关键词: affinity chromatography; angiogenesis; binding proteins; binding sites; biological signal transduction; cell migration; chemotaxis; confocal scanning microscopy; crosslink; enzyme activity; enzyme mechanism; enzyme structure; expression cloning; immunoprecipitation; intraluminal angioplasty; laboratory rat; low density lipoprotein receptor; muscle cells; protein localization; protein protein interaction; receptor binding; urokinase; vascular smooth muscle; western blottings

Urokinase plasminogen activator (uPA) has been implicated in fibrinolysis and diverse processes that involve cell migration such as atherosclerosis, angiogenesis, wound repair, and tumor metastases. Studies in mice with targeted deletion of the genes for uPA and uPAR indicate that uPA induces transmembrane signaling through pathways discrete from those involved in binding to its glycolipid-anchored receptor (uPAR), but to date the details of this mechanism have not been elucidated. uPA is composed of a receptor-binding growth factor domain, a kringle domain, the function of which is unknown, and a protease domain. Recent studies from our laboratories demonstrate that the kringle of uPA binds to vascular smooth muscle cells (VSMC) and delivers a signal that potentiates uPA-mediated VSMC contraction and cell migration. Further, recognition of the kringle mediates clearance of uPA from cell surfaces, suggesting the kringle domain represents an important control point in VSMC function. We now propose to extend these studies and to examine these newly described properties of the uPA kringle in greater detail through five inter-related specific aims. 1) We will characterize the interaction of the uPA kringle with the low-density lipoprotein receptor/alpha2 macroglobulin receptor which mediates uPA degradation. 2) We will isolate and identify the uPA-kringle binding protein on VSMC. 3) We will examine the kringle-mediated signal transduction pathway in VSMC. 4) We will study the interaction between kringle binding protein-dependent and uPAR-dependent signal transduction events in VSMC using uPA variants capable of activation either or both pathways. 5) We will examine the role of the uPA kringle and kringle binding protein in vascular wall remodeling in a rat model of intravascular trauma. These studies will provide insight into a newly described uPA-mediated signal transduction pathway involved in smooth muscle cell migration and vascular repair. Identification of the kringle binding protein may provide an opportunity to modulate the contribution of vascular smooth muscle cell proliferation and migration to atherosclerosis and restenosis.

尿激酶纤溶酶原激活剂 (uPA) 与纤维蛋白溶解有关 涉及细胞迁移的多种过程，例如动脉粥样硬化， 血管生成、伤口修复和肿瘤转移。对小鼠进行靶向研究 uPA 和 uPAR 基因的缺失表明 uPA 诱导跨膜 通过与参与结合的途径分离的途径发出信号 糖脂锚定受体（uPAR），但迄今为止该机制的细节 尚未阐明。 uPA 由受体结合​​生长因子组成 结构域、功能未知的 kringle 结构域和蛋白酶 领域。我们实验室的最新研究表明， uPA 与血管平滑肌细胞 (VSMC) 结合并传递信号 增强 uPA 介导的 VSMC 收缩和细​​胞迁移。更远， 对 kringle 的识别介导 uPA 从细胞表面的清除， 表明 kringle 结构域是 VSMC 的一个重要控制点 功能。我们现在建议扩展这些研究并检验这些新的 通过五个更详细地描述了 uPA kringle 的属性 相互关联的具体目标。 1）我们将描述uPA的相互作用 具有低密度脂蛋白受体/α2巨球蛋白受体的 kringle 介导 uPA 降解。 2) 我们将分离并鉴定uPA-kringle VSMC 上的结合蛋白。 3）我们将检查 kringle 介导的信号 VSMC 中的转导途径。 4）我们将研究kringle之间的相互作用 VSMC 中结合蛋白依赖性和 uPAR 依赖性信号转导事件 使用能够激活任一途径或两条途径的uPA变体。 5）我们会 检查 uPA kringle 和 kringle 结合蛋白在血管中的作用 血管内创伤大鼠模型中的壁重塑。这些研究将 深入了解新描述的 uPA 介导的信号转导途径 参与平滑肌细胞迁移和血管修复。鉴定 kringle结合蛋白可能提供调节的机会 血管平滑肌细胞增殖和迁移的贡献 动脉粥样硬化和再狭窄。