PTDINS-4-PHOSPHATE 5-KINASE IN P21RAC SIGNALING

P21RAC 信号传导中的 PTDINS-4-磷酸 5-激酶

• 批准号: 2392287
• 负责人: CHRISTOPHER CARPENTER
• 金额: $ 19.27万
• 依托单位: BETH ISRAEL DEACONESS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-04-01 至 2001-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2392287
• 关键词: actins; alcohol phosphotransferase; biological signal transduction; cell adhesion; cell motility; cytoskeleton; enzyme activity; enzyme mechanism; guanine nucleotide binding protein; guanosinetriphosphatases; intermolecular interaction; membrane activity; molecular cloning; phosphatidylinositols; platelet activation; protein purification; tissue /cell culture

DESCRIPTION: (Adapted from the abstract) The principal goal of this application is to define the role of phosphatidylinositol kinases in signaling by the small GTP-binding protein Rac. Rac is involved in regulating the actin cytoskeleton in membrane ruffling, motility, cell adherence and maintenance of cell shape. The applicant presents evidence that Rac interacts with and may regulate a PI-4 5K and PI-3 kinase (PI 3K) and findings suggesting that Rac's regulation of the cytoskeleton may be mediated by production of specific phospholipids, since phosphatidylinositol-4,5-bisphosphate (PIP2) binds to and regulates function of actin regulatory proteins. Experiments are proposed to determine the role of PI-4 5K in vivo and to determine effects of Rac on this enzyme's activity and localization in cells. The Rac-associated PI-4 5K will be purified and a cDNA clone obtained. The regions of Rac and the kinase necessary for interacting with one another will be identified, and mutants constructed with specific loss of ability to participate in this interaction, for use as dominant negative reagents in studying Rac/PIP2/cytoskeleton signaling. Interactions among Rac, PI-4 5K and other regulatory proteins (RhoGDI, exchange proteins, etc.) will be studied with pure recombinant proteins to determine the mechanism of activation of PIP2 synthesis. In addition, experiments are described to determine whether a Rac/PI 3K complex is necessary for cell adherence and whether PI 3K acts downstream of Rac, using a PI 3K dominant negative construct.

描述：（改编自摘要）本研究的主要目标 应用是定义磷脂酰肌醇激酶在 通过小GTP结合蛋白Rac进行信号传导。 Rac参与了 调节肌动蛋白细胞骨架在膜褶皱，运动，细胞 细胞形状的粘附和维持。 申请人提出 Rac与PI-4 5 K和PI-3相互作用并可能调节PI-4 5 K和PI-3的证据 激酶（PI 3 K）和研究结果表明，Rac的调节， 细胞骨架可以通过产生特异性磷脂来介导， 由于磷脂酰肌醇-4，5-二磷酸（PIP 2）结合并调节 肌动蛋白调节蛋白的功能。 实验被提议为 确定PI-4 5 K在体内的作用，并确定Rac对 这种酶的活性和在细胞中的定位。 Rac相关 纯化PI-4 5 K并获得cDNA克隆。 Rac地区 而相互作用所必需的激酶 鉴定，并构建具有特定丧失能力的突变体， 参与这种相互作用，用作显性阴性试剂 研究Rac/PIP 2/细胞骨架信号。 Rac之间的互动， PI-4 5 K和其他调节蛋白（RhoGDI、交换蛋白等） 将用纯的重组蛋白进行研究，以确定 PIP 2合成的激活机制。 此外，实验还 描述了用于确定Rac/PI 3 K复合物对于细胞增殖是否是必需的。 遵守以及PI 3 K是否使用PI 3 K在Rac下游运行 显性否定结构