INTEGRIN AND VIRAL TRANSFORMATION

整合素和病毒转化

• 批准号: 2700423
• 负责人: DAVID E BOETTIGER
• 金额: $ 28.5万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-05-01 至 2000-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2700423
• 关键词: Rous sarcoma virus; acidity /alkalinity; biological signal transduction; cell adhesion; cell cycle; cell transformation; chick embryo; contact inhibition; extracellular matrix; extracellular matrix proteins; fibroblasts; gene expression; growth factor; guanine nucleotide binding protein; immunofluorescence technique; integrins; mitogens; monoclonal antibody; northern blottings; oncogenes; phosphorylation; receptor binding; regulatory gene; synchronous cell division; tissue /cell culture

Transformation of cells by Rous sarcoma virus is dependent on the expression of virus encoded src gene. Experiments using microinjection or co-expression of dominant negative ras or raf genes has suggested that the mechanism by which v-src transforms cells involves ras and raf mediated signal transduction. But these conditions not only suppress v-src induced cell transformation, they also suppress normal cell proliferation. An alternative view is that v-src functions through its interaction with molecules involved in cell adhesion and determination of cell shape. The difficulty with this view is that there is little functional data to support it and the potential mechanisms by which cell adhesion may alter cell gene expression and cell proliferation are at a very early stage of development. The objective of this proposal is to fill this void and test the hypothesis that v-src operates by interfering with normal cell signaling pathways which are linked to cell adhesion and particularly to integrin family receptors. To test this proposition, we will reexamine two old model systems for cell transformation from the perspective of a possible link between v-src dependent cell proliferation and v-src mediated modulation of integrin mediated cell adhesion. (i) Deprivation of serum causes cells to arrest in Go. Activation of v-src in the arrested cells induces cell proliferation. The role of integrins in the establishment of the quiescent state and the potential requirement for integrin modulation to reinitiate cell proliferation will be tested. Does v-src induced proliferation depend on its effect to weaken integrin extracellular matrix links? (ii) Transformed fibroblasts are able to proliferate in suspension whereas normal fibroblasts require an adhesive substrate. The role of integrins in supplying this adhesion signal and the possibility that v-src disrupts this signal will be examined using cell cycle analysis, functional analysis of adhesion requirements and genetic manipulation.

劳斯肉瘤病毒对细胞的转化取决于 病毒编码的src基因的表达。 使用显微注射或 显性失活 ras 或 raf 基因的共表达表明 v-src转化细胞的机制涉及ras和raf介导 信号转导。 但这些条件不仅抑制 v-src 诱导 细胞转化的同时，它们还抑制正常细胞增殖。 一个 另一种观点是 v-src 通过与 参与细胞粘附和细胞形状决定的分子。 这 这种观点的困难在于，几乎没有什么功能数据可以证明这一点。 支持它以及细胞粘附可能改变的潜在机制 细胞基因表达和细胞增殖处于非常早期的阶段 发展。 该提案的目的是填补这一空白并测试 v-src 通过干扰正常细胞发挥作用的假设 与细胞粘附相关的信号通路，特别是 整合素家族受体。 为了测试这个命题，我们将重新检查细胞的两个旧模型系统 从v-src之间可能存在联系的角度进行改造 依赖性细胞增殖和 v-src 介导的整合素调节 介导的细胞粘附。 (i) 剥夺血清会导致细胞停滞 在围棋中。停滞细胞中 v-src 的激活诱导细胞 增殖。 整合素在建立静止状态中的作用 整合素调节重新启动的状态和潜在要求 将测试细胞增殖。 v-src 诱导的增殖是否依赖于 其削弱整合素细胞外基质连接的作用？ (二) 转化的成纤维细胞能够在悬浮液中增殖，而 正常的成纤维细胞需要粘附基质。 整合素的作用 提供这种粘附信号以及 v-src 破坏的可能性 将使用细胞周期分析、功能分析来检查该信号 粘附要求和遗传操作。