REGULATION OF PAXILLIN SIGNALING

描述：桩蛋白是一种70 kDa的蛋白质，定位于局灶性粘连， 细胞与基质的附着点。酪氨酸 桩蛋白和p125FAK（另一种粘着斑蛋白）的磷酸化， 受到多种病毒和细胞因子的刺激最近 研究，由申请人作为博士后研究员进行，表明 p125 FAK与桩蛋白相互作用，pp125 FAK可以磷酸化 桩蛋白这项研究的中心假设是， pp125FAK介导的桩蛋白酪氨酸磷酸化调节细胞凋亡 通过募集含有SH2的蛋白质形成信号复合物。 有四个具体目标。pp125FAK和桩蛋白内的序列 介导蛋白质：蛋白质相互作用的蛋白质将使用 酵母双杂交方法（Aim I）。接下来，Src和FAK介导的 桩蛋白上的磷酸化将通过突变酪氨酸而改变， 苯丙氨酸，以及突变的桩蛋白结合 将评估已知蛋白质的SH2结构域（Aim II）。在Aim III中， 将检测已知和未知的与桩蛋白结合的蛋白质。 最后，含有桩蛋白的信号复合物的重要性将 通过破坏结合到 酪氨酸磷酸化桩蛋白。对细胞转化的影响， 将研究细胞迁移。

DESCRIPTION: Paxillin is a 70 kDa protein localized to focal adhesions, points of attachment of the cell to the substratum. Tyrosine phosphorylation of paxillin and p125FAK, another focal adhesion protein, is stimulated by a number of different viral and cellular agents. Recent studies, performed by the applicant as a Postdoctoral Fellow, indicate that p125FAK and paxillin interact, and that pp125FAK can phosphorylate paxillin. The central hypothesis of the proposed research is that pp125FAK mediated tyrosine phosphorylation of paxillin regulates the formation of signaling complexes, by recruiting SH2 containing proteins. Four specific Aims are described. Sequences within pp125FAK and paxillin which mediate protein:protein interaction will be defined using the yeast two-hybrid method (Aim I). Next, the sites of Src and FAK-mediated phosphorylation on paxillin will be altered by mutating tyrosines to phenylalanines, and the ability of the mutated paxillin proteins to bind SH2 domains of known proteins will be assessed (Aim II). In Aim III, proteins that bind to paxillin, both known and unknown will be examined. Finally, the importance of paxillin containing signaling complexes will be determined by disrupting SH2-containing protein complexes bound to tyrosine phosphorylated paxillin. The effects on cell transformation and cell migration will be studied.