Kindlin-2 in Cell-Matrix Adhesion and Signaling

描述（由申请人提供）：这个竞争性更新申请的长期目标是阐明细胞-细胞外基质（ECM）粘附和调节的分子基础，以及它们控制细胞行为、组织完整性、生长和再生的机制。申请人和其他人最近的研究表明，kindin -2（也称为Mig-2）是一种广泛表达的膜-细胞骨架连接蛋白，在整合素激活和细胞- ecm粘附中起关键作用。然而，kindin -2如何调节这些过程尚不清楚。基于先前项目期间获得的发现，申请人假设kindin -2通过与膜脂和细胞- ecm粘附的蛋白质成分相互作用来调节这些过程。为了验证这一假设，他提出了以下三个目标的研究。目的1是表征kindin -2与膜脂的相互作用，并评估其在整合素和整合素依赖过程中的调节作用。为此，他将采用遗传、药理学和显性负抑制策略来消除这种相互作用，并确定后果。目的2是确定kindin -2与局灶黏附蛋白相互作用在调节细胞- ecm黏附中的功能。他将确定介导相互作用的位点，并使用“敲入”策略，用缺乏特定蛋白质结合活性的突变体取代野生型kindin -2，并确定结果。目的3是研究kindin -2在肝脏结构、生长和再生中的功能及其与ILK的相互作用，已知这些功能受ECM粘附和ILK信号传导的调节。他将产生肝细胞特异性kindlin-2敲除和敲入小鼠，将野生型kindlin-2替换为缺乏特异性结合活性的kindlin-2突变体，并确定kindlin-2及其相互作用对肝细胞行为、肝脏结构、生长和再生的调节作用。这些研究将填补我们对细胞- ecm粘附和ecm依赖性组织过程调节机制的理解中的重要空白。鉴于细胞- ecm粘附在人类疾病中的重要性，这些研究也可能导致新的方法来控制与异常细胞- ecm粘附和信号相关的疾病。

DESCRIPTION (provided by applicant): The long-term goal of this competing renewal application is to elucidate the molecular basis underlying cell- extracellular matrix (ECM) adhesion and regulation, and the mechanism whereby they control cell behavior, tissue integrity, growth and regeneration. Recent studies by the applicant and others have demonstrated a critical role of kindlin-2 (also known as Mig-2), a widely expressed membrane-cytoskeleton junctional protein, in integrin activation and cell-ECM adhesion. How kindlin-2 regulates these processes, however, is not known. Based on findings obtained during previous project periods, the applicant hypothesizes that kindlin-2 regulates these processes through interacting with membrane lipids and protein components of cell-ECM adhesions. To test this hypothesis, he proposes studies with the following three aims. Aim 1 is to characterize the interaction of kindlin-2 with membrane lipids and assess its role in regulation of integrins and integrin-dependent processes. To this end, he will employ genetic, pharmacological and dominant negative inhibition strategies to ablate this interaction, and determine the consequences. Aim 2 is to determine the functions of kindlin-2 interactions with focal adhesion proteins in regulation of cell-ECM adhesion. He will define the sites mediating the interactions and use a "knock-in" strategy to replace wild type kindlin-2 with mutants lacking specific protein-binding activity and determine the consequences. Aim 3 is to investigate the functions of kindlin-2 and its interplay with ILK in liver structure, growth and regeneration, which are known to be regulated by ECM adhesion and ILK signaling. He will generate hepatocyte-specific kindlin-2 knockout and "knock-in" mice, in which wild type kindlin-2 is substituted with kindlin-2 mutants lacking specific binding activities, and determine contributions of kindlin-2 and its interactions to regulation of hepatocyte behavior, liver structure, growth and regeneration. These studies will fill important gaps in our understanding of the mechanism whereby cell-ECM adhesion and ECM-dependent tissue processes are regulated. Given the importance of cell-ECM adhesion in human diseases, these studies may also lead to novel approaches to control diseases associated with abnormal cell-ECM adhesion and signaling.