MODULATION OF ALPHA 5 BETA 1 INTEGRIN

ALPHA 5 BETA 1 整合素的调节

• 批准号: 6525439
• 负责人: DAVID E BOETTIGER
• 金额: $ 28.86万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-08-01 至 2003-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6525439
• 关键词: actins; bioengineering /biomedical engineering; biological signal transduction; biomechanics; biomedical equipment development; cell adhesion; chemical models; crosslink; fibronectins; integrins; measurement; mechanical pressure; physical model; protein isoforms; receptor binding; tissue /cell culture

DESCRIPTION (Adapted from applicant's abstract): Alpha5beta1 is a member of the integrin family of cell adhesion receptors which serve both the mechanical function of adhering cells and a signaling function in the control of many cell processes. It is likely that the mechanical and signaling aspects of alpha5beta1 function are linked since some alpha5beta1 signaling functions cannot be replaced by ligand binding alone. To examine the mechanical aspects of alpha5beta1 function and regulation of alpha5beta1 mediated cell adhesion, a spinning disc device has been engineered to provide a measurement of the force required to detach cells from a substrate. By applying concepts from chemical binding analysis it has been possible to convert the adhesion data to a model of monovalent receptor-ligand binding and demonstrate that there is a linear relationship between the number of integrin-extracellular matrix bonds and the force required to detach the cell. The proposal considers models to explain activation of alpha5beta1 binding to fibronectin: agonist activation, induced-fit activation, clustering activation, and tension activation. Each of these models makes different predictions for ligand, cytoskeletal, and energy requirements. These requirements would be tested using biochemical predictions. Inhibitors, and genetic analysis of fibronectin mutants, beta1 cytoplasmic domain splice variants, and beta1 cytoplasmic domain mutants. The analysis views the adhesion connection as one from fibronectin to alpha5beta1 to actin cytoskeleton and these connections, either ligand binding or cytoskeletal binding, can control the adhesion strength. Procedures have been developed to assay these connections separately. Their approach would be extended to the examination of long term (or steady-state) adhesion, including analysis of the increase in the number of alpha5beta1 receptors bound, and the role of clustering n the adhesion strengthening-cell spreading process.

描述（改编自申请人的摘要）：Alpha5beta1 是 细胞粘附受体的整合素家族，其既服务于机械 粘附细胞的功能和控制许多细胞的信号传导功能 流程。机械和信号方面很可能 由于某些 alpha5beta1 信号传导功能，因此 alpha5beta1 功能相互关联 不能仅通过配体结合来替代。检查机械方面 α5β1 功能和 α5β1 介导的细胞粘附的调节， 旋转盘装置被设计用于提供力的测量 将细胞从基质上分离所需的。通过应用化学概念 结合分析可以将粘附数据转换为模型 的单价受体-配体结合并证明存在线性 整合素-细胞外基质键的数量与 分离细胞所需的力。该提案考虑模型来解释 α5β1 与纤连蛋白结合的激活：激动剂激活， 诱导拟合激活、聚类激活和张力激活。每一个 这些模型对配体、细胞骨架和能量做出不同的预测 要求。这些要求将使用生化预测进行测试。 纤连蛋白突变体的抑制剂和遗传分析，β1 细胞质 结构域剪接变体和 beta1 胞质结构域突变体。分析 将粘附连接视为从纤连蛋白到 α5β1 到肌动蛋白的一个连接 细胞骨架和这些连接，无论是配体结合还是细胞骨架 粘合，可控制粘合强度。已制定程序以 分别分析这些连接。他们的方法将扩展到 长期（或稳态）粘附力的检查，包括分析 结合的 α5β1 受体数量增加，以及 粘附强化细胞扩散过程中的聚集。