ILK Signaling in Renal Growth and Matrix Deposition

描述（由申请人提供）：肾脏（如肾小球系膜）细胞粘附、生长和细胞外基质沉积在终末期肾衰竭的进展中至关重要。这个竞争性延续应用的长期目标是阐明肾细胞控制这些过程的分子机制。在这个竞争性延续应用中提出的研究集中在整合素连接激酶（ILK）的作用上，ILK是细胞-基质接触位点的关键组成部分，在肾小球系膜细胞行为的调节中。目的1是验证PINCH/ILKICH-ILKBP复合物在肾小球系膜细胞-基质接触部位提供整合素和肌动蛋白细胞骨架之间的关键连接，从而调节系膜细胞的粘附、生长和纤维连接蛋白基质沉积的假设。破坏PINCH/ILKICH-ILKBP复合物形成的显性阴性抑制剂将通过腺病毒感染引入原代系膜细胞，并确定其对系膜细胞粘附、增殖和纤维连接蛋白基质沉积的影响。目的2是验证PINCH-RP（一种新发现的PINCH-RP相关蛋白，其在肾小球系膜细胞中的表达受葡萄糖调节）是系膜细胞中P1INCH/ILKICH-ILKBP复合物组装和功能的自然负调节因子的假设。分子和细胞方法的结合将用于确定P1NCH-RP在系膜细胞中的功能。目的3是对Mig-2进行分子表征，Mig-2是一种新发现的与PINCH/ILKICH-ILKBP复合物共定位并物理关联的蛋白，并确定其是否作为促进ILK复合物在系膜细胞中的定位和功能的正调节因子。这些研究将促进我们对控制肾小球系膜细胞粘附、生长和细胞外基质沉积的分子机制的认识。它们可能会导致新的治疗方法的发展，以控制与异常肾细胞粘附、增殖和细胞外基质沉积密切相关的终末期肾衰竭。

DESCRIPTION (provided by applicant): Renal (e.g., glomerular mesangial) cell adhesion, growth and extracellular matrix deposition are crucially involved in the progression of end-stage renal failure. The long-term goal of this competing continuation application is to elucidate the molecular mechanism by which renal cells control these processes. The studies proposed in this competing continuation application focus on the role of integrin-linked kinase (ILK), a key component of cell-matrix contact sites, in the regulation of glomerular mesangial cell behavior. Aim 1 is to test the hypothesis that a PINCH/ILKICH-ILKBP complex provides a key connection between integrins and the actin cytoskeleton at glomerular mesangial cell-matrix contact sites and thereby regulates mesangial cell adhesion, growth and fibronectin matrix deposition. Dominant negative inhibitors that disrupt the formation of the PINCH/ILKICH-ILKBP complex will be introduced into primary mesangial cells by adenoviral infection and their effects on mesangial cell adhesion, proliferation and fibronectin matrix deposition will be determined. Aim 2 is to test the hypothesis that PINCH-RP, a newly identified PiNCH-related protein whose expression in glomerular mesangial cells is regulated by glucose, is a naturally occurring negative regulator of the assembly and functions of the P1INCH/ILKICH-ILKBP complex in mesangial cells. A combination of molecular and cellular approaches will be used to determine the functions of P1NCH-RP in mesangial cells. Aim 3 is to molecularly characterize Mig-2, a newly identified protein that co-localizes and physically associates with the PINCH/ILKICH-ILKBP complex, and to determine whether it functions as a positive regulator facilitating the localization and functions of the ILK complex in mesangial cells. These studies will advance our knowledge on the molecular mechanisms that govern glomerular mesangial cell adhesion, growth and extracellular matrix deposition. They could potentially lead to development of novel therapeutic approaches to control end-stage renal failure that is intimately associated with abnormal renal cell adhesion, proliferation and extracellular matrix deposition.