ROLE OF CELL ADHESION IN BIOLOGICAL SIGNAL TRANSDUCTION

细胞粘附在生物信号转导中的作用

• 批准号: 6238317
• 负责人: GALEN B SCHNEIDER
• 金额: $ 2.26万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-07-01 至 1998-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6238317
• 关键词: affinity chromatography; biological signal transduction; cell adhesion; cell differentiation; dental implants; extracellular matrix; fibroblasts; immunofluorescence technique; immunologic assay /test; immunoprecipitation; osteoblasts; protein purification; protein tyrosine phosphatase; tissue /cell culture; western blottings; wound healing

Focal adhesions (FA) are prominent transmembrane structures of many cells in culture. Individual FA's serve to link the extracellular matrix (ECM) to the actin cytoskeleton, and to initiate a cascade of signalling pathways through integrin receptors. The regulation of these cellular signalling pathways is important with respect to many cellular functions including growth and differentiation, tumorigenesis, wound healing, osseointegration, and the formation of a mineralized matrix. The objective of this study was to evaluate protein tyrosine phosphatase (PTP) activity that may regulate tyrosine phosphorylation in FA's. Using a PTP assay, we have confirmed the observations of Maher (PNAS 90:11177, 1993) that lysates of fibroblasts in suspension have elevated PTP activity when compared with lysates of adherent fibroblasts. Looking for PTP's that may be adhesion regulated, we have identified the cytoplamic PTP, PTPDl, in immunoprecipitates of the FA protein paxillin. We are currently exploring this interaction and the relationship of this PTP to FA's. Microinjection of the cytoplasmic domain of a receptor-type PTP, PTP , (GST fusion protein subclone generously provided by Mathew Thomas, Wash. Univ., St. Louis) into adherent fibroblasts depleted the tyrosine phosphorylation in FA's. However, the FA structure appeared to be stable as judged by staining with anti-vinculin. Our results suggest that the tyrosine phoshorylation in FAs is regulated not only by kinases but also by PTP's.

粘着斑 (FA) 具有突出的跨膜性 培养物中许多细胞的结构。 各个 FA 的作用是将 细胞外基质 (ECM) 到肌动蛋白细胞骨架，并启动 通过整合素受体的信号通路级联。 法规 这些细胞信号传导途径的研究对于许多方面都很重要 细胞功能，包括生长和分化、肿瘤发生、 伤口愈合、骨整合和矿化骨的形成 矩阵。 本研究的目的是评估蛋白质酪氨酸 磷酸酶（PTP）活性可能调节酪氨酸磷酸化 FA 的。 使用 PTP 测定，我们证实了 Maher 的观察结果 (PNAS 90:11177, 1993) 悬浮的成纤维细胞裂解物具有 与贴壁成纤维细胞裂解物相比，PTP 活性升高。 寻找可能受到粘附调节的 PTP，我们已经确定了 FA蛋白桩蛋白的免疫沉淀物中的细胞质PTP，PTPD1。 我们目前正在探索这种相互作用以及这种关系 PTP 到 FA。 受体型细胞质结构域的显微注射 PTP, PTP , (GST 融合蛋白亚克隆由 Mathew 慷慨提供 Thomas，华盛顿大学，圣路易斯）进入贴壁成纤维细胞，耗尽了 FA 中的酪氨酸磷酸化。 然而，FA 结构似乎 通过抗纽蛋白染色判断是否稳定。 我们的结果表明 FA 中的酪氨酸磷酸化不仅受激酶调节 也是通过PTP的。