ILK SIGNALING--RENAL CELL GROWTH AND MATRIX DEPOSITION

肾细胞增殖和细胞外基质异常 蓄积是糖尿病肾病的致病因素。长期的 我们研究的目的是阐明分子信号转导。 调节肾细胞增殖和细胞外的机制 基质沉积。纤维连接蛋白(FN)是肾脏的重要组成部分 细胞外基质。纤维连接蛋白基质沉积是由 特异性FN结合整合素，并且基质沉积过程可以 受控制整合素活性的信号通路调节。 整合素连接的激酶，一种与整合素有关的丝氨酸/苏氨酸激酶 信号转导，参与FN基质沉积的调节和 细胞增殖。ILK在模型细胞系统中的过表达 刺激FN基质沉积。此外，ILK在系膜细胞中的表达 血管紧张素II和高糖使细胞数量增加。 整合素连接的激酶可能与IRS-1信号转导有关 LIM蛋白PINCH介导的相互作用途径和一种新的 Sh2/SH3含有与Nck同源的蛋白质(指定为 NCK-2)。这项研究项目旨在批判性地评估 ILK信号在调节肾细胞增殖和FN中的作用 基质沉积。首先，ILK将在系膜细胞中过度表达 DNA转移方法及其对整合素活化和纤维连接蛋白的影响 将确定基质沉积情况。第二，两国之间的互动 ILK、PINCH、NCK-2和IRS-1将在体外和细胞内进行分析，以及 将产生抑制特定相互作用的试剂。 最后，特定蛋白质--蛋白质的功能意义 肾FN基质沉积与细胞增殖的相互作用 通过将抑制性试剂引入肾脏来测定 系膜和间质成纤维细胞。 拟议的研究将阐明ILK信号的作用。 肾细胞增殖与纤维连接蛋白基质的调控途径 沉积，并有可能转化为新的治疗方法 控制基质沉积和细胞增殖的方法， 因此，糖尿病肾病的转归。

Abnormalities in renal cell proliferation and extracellular matrix accumulation are causal factors of diabetic nephropathy. The long-term objective of our research is to elucidate the molecular signaling mechanisms that regulate renal cell proliferation and extracellular matrix deposition. Fibronectin (Fn) is an important component of renal extracellular matrices. Fibronectin matrix deposition is initiated by specific Fn binding integrins, and the matrix deposition process can be regulated by signaling pathways that control the integrin activities. Integrin-linked kinase, a serine/threonine kinase implicated in integrin signaling, is involved in the regulation of Fn matrix deposition and cell proliferation. Overexpression of ILK in a model cell system stimulated Fn matrix deposition. Moreover, ILK expression in mesangial cells was increased in response to angiotensin II and high glucose. Integrin-linked kinase is potentially linked to the IRS-1 signaling pathways via interactions mediated by the LIM protein PINCH and a novel SH2/SH3 containing protein that is homologous to Nck (designated as Nck-2). This research project is designed to critically evaluate the role of ILK signaling in regulating renal cell proliferation and Fn matrix deposition. First, ILK will be over-expressed in mesangial cells by DNA transfer methods and its effect on integrin activation and Fn matrix deposition will be determined. Second, the interactions between ILK, PINCH, Nck-2 and IRS-1 will be analyzed in vitro and in cells, and reagents that inhibit the specific interactions will be generated. Finally, the functional significance of the specific protein-protein interactions in renal Fn matrix deposition and cell proliferation will be determined by introducing the inhibitory reagents into renal mesangial and interstitial fibroblastic cells. The proposed studies will elucidate the role of the ILK signaling pathway in regulation of renal cell proliferation and Fn matrix deposition, and may potentially translate into novel therapeutic approaches to control matrix deposition and cell proliferation and, consequently, the outcome of diabetic nephropathy.