p47 binding partners in endothelial cell function

描述（由申请人提供）：在许多人类血管疾病的进化过程中，血管内皮的表型发生了巨大的变化，在胚胎血管发育过程中发生了概括的变化。类似于上皮细胞到间质细胞的转换，激活迁移和增殖途径，在肿瘤或伤口愈合的血管生成反应中以及炎症损伤后血管的恢复过程中都可以看到。这种内皮细胞迁移和增殖的耦合反映了细胞命运决定和细胞骨架力学在功能、生化和空间水平上的联系。特别是迁移细胞表现出显著的近端信号蛋白的亚细胞极化，这些信号蛋白控制着细胞骨架动力学以及生存和增殖途径。值得注意的是，内源性产生的活性氧化剂已被证明集中在迁移内皮细胞的前沿，并且似乎是运动和有丝分裂信号传导所必需的。这些观察结果表明，内皮细胞氧化酶可能类似地靶向前缘结构，并且这种精确的靶向可能对保持氧化相关信号的保真度至关重要。然而，这种假定的亚细胞氧化酶定位的分子基础和生物学原理实际上是未知的。在之前的资助期内，我们确定了主要NADPH氧化酶适配器p47phox的一些蛋白质结合伙伴，并证明了几种蛋白质-蛋白质相互作用在指定氧化相关信号传导到特定信号传导模块中的参与。在本应用中，我们建议通过显微、生化和功能研究的结合，详细研究这些相互作用在改变内皮表型中的作用。与公共卫生的相关性：在美国，导致死亡的主要原因是癌症和心血管疾病，这些疾病涉及血管内皮表型的根本变化。我们建议详细研究这些变化的生化基础的一个方面，以期逆转或防止这些变化。该应用程序是R01-HL67256的竞争性更新。

DESCRIPTION (provided by applicant): The phenotype of the vascular endothelium changes dramatically in the evolution of a number of human vascular diseases, recapitulating changes seen during embryonic vascular development. A switch similar to the epithelial-to-mesenchymal transition, activating migration and proliferation pathways, is seen during the angiogenic response to tumors or healing wounds and also during the restitution of vessels following inflammatory injury. This coupling of endothelial cell migration and proliferation reflects the linkage between cell fate decisions and cytoskeletal mechanics at functional, biochemical, and spatial levels. Migrating cells in particular display striking subcellular polarization of proximal signaling proteins which govern cytoskeletal dynamics as well as survival and proliferation pathways. Notably, endogenously- produced reactive oxidants have been shown to concentrate at the leading edge of migrating endothelial cells, and appear to be necessary for both locomotion and mitogenic signaling. These observations suggest that the endothelial cell oxidase may be similarly targeted to leading edge structures, and that such precise targeting may be essential to preserve the fidelity of oxidant-related signals. However, the molecular basis and biological rationale for such putative subcellular oxidase localization is virtually unknown. During the prior funding period, we identified a number of protein binding partners of the principal NADPH oxidase adapter, p47phox, and demonstrated the involvement of several protein-protein interactions in specifying oxidant-related signaling to specific signaling modules. In this application, we propose to examine in detail the role of these interactions in changing the endothelial phenotype, using a combination of microscopic, biochemical, and functional studies. Relevance to Public Health: Diseases that account for the leading causes of death in the United States, among them cancer and cardiovascular disease, involve fundamental changes in the phenotype of the vascular endothelium. We propose to investigate in detail one facet of the biochemical basis for these changes, in hopes of reversing or preventing these changes. This application is a competing renewal of R01-HL67256.