NANOSCALE: Structural Changes in Fibronectin Binding Domains upon Adsorption to Well-Defined Surface Chemistries

纳米尺度：吸附到明确的表面化学物质后纤连蛋白结合域的结构变化

• 批准号: 9986549
• 负责人: Andres Garcia
• 金额: $ 20万
• 依托单位: Georgia Tech Research Corporation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-03-01 至 2002-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9986549&HistoricalAwards=false
• 关键词: NANOSCALE; Structural; Changes; Fibronectin; Binding

Cell adhesion to proteins adsorbed onto material surfaces is critical to numerous biomedical and biotechnological applications, including biomaterials, tissue engineering, and in vitro cell culture systems. Cell attachment to extracellular proteins is primarily mediated by the integrin family of cell surface receptors. Integrins bind to specific amino acid sequences in extracellular matrix components. For example, integrin a5b1 binds to the PHSRN and RGD domains in fibronectin (Fn). This interaction is controlled by the relative structural orientation of these two domains, which are 3-4 nm apart. Each domain independently contributes little to binding, but in combination, they synergistically bind to the receptor to produce significant increases in adhesion. Moreover, upon adsorption to surfaces, Fn undergoes structural changes that modify a5b1 binding, suggesting changes in the relative orientation of these binding domains.This project focuses on modeling the adsorption of a well-characterized fragment of Fn (FnIII7-10), which contains the PHSRN and RGD binding sites, onto self-assembled monolayers of alkanethiols presenting well-defined surface chemistries (CH3, NH2, COOH, and OH). Specifically, innovative experimental and computational approaches are integrated to model changes in the relative orientation of the PHSRN and RGD domains and the relationship between these structural changes and integrin binding. First, the conformation of adsorbed FnIII7-10 will be characterized using monoclonal antibodies and structural and thermodynamic information obtained from molecular simulations. The functional binding of integrin a5b1 to adsorbed FnIII7-10, characterized by adhesion strength and relative binding affinity, will then be analyzed and correlated to the structural parameters. By integrating experimental and computational approaches, this analysis will provide a mechanistic understanding of protein-surface interactions and the role of adsorption-induced structural changes in protein function. Finally, the proposed research will provide an analytical framework that is applicable to other protein/surface

细胞粘附到材料表面吸附的蛋白质对于许多生物医学和生物技术应用至关重要，包括生物材料、组织工程和体外细胞培养系统。 细胞与细胞外蛋白质的附着主要由细胞表面受体的整合素家族介导。 整合素与细胞外基质成分中的特定氨基酸序列结合。 例如，整合素 a5b1 与纤连蛋白 (Fn) 中的 PHSRN 和 RGD 结构域结合。 这种相互作用是由这两个域的相对结构方向控制的，这两个域相距 3-4 nm。 每个结构域独立地对结合贡献很小，但组合起来，它们协同结合受体，从而显着增加粘附力。 此外，吸附到表面后，Fn 会发生结构变化，从而修改 a5b1 结合，表明这些结合域的相对方向发生变化。该项目重点是对 Fn (FnIII7-10) 的充分表征片段的吸附进行建模，其中包含PHSRN 和 RGD 结合位点，在链烷硫醇的自组装单层上，呈现明确的表面化学性质（CH3、NH2、COOH 和 OH）。 具体来说，创新的实验和计算方法被整合起来，以模拟 PHSRN 和 RGD 结构域相对方向的变化以及这些结构变化和整合素结合之间的关系。 首先，将使用单克隆抗体以及从分子模拟获得的结构和热力学信息来表征吸附的 FnIII7-10 的构象。 然后将分析整合素 a5b1 与吸附的 FnIII7-10 的功能结合，以粘附强度和相对结合亲和力为特征，并将其与结构参数相关联。 通过整合实验和计算方法，该分析将对蛋白质-表面相互作用以及吸附诱导的结构变化在蛋白质功能中的作用提供机械理解。 最后，拟议的研究将提供一个适用于其他蛋白质/表面的分析框架