TRANSCRIPTIONAL REPRESSION BY C-SKI AND MELANOMA

C-SKI 和黑色素瘤的转录抑制

• 批准号: 6260080
• 负责人: ESTELA E MEDRANO
• 金额: $ 10万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-04-01 至 2000-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6260080
• 关键词: biological signal transduction; centrosome; gene expression; gene induction /repression; genetic promoter element; genetic transcription; human tissue; melanoma; molecular genetics; neoplasm /cancer genetics; pathologic process; protein binding; protein structure function; tissue /cell culture; transcription factor; transforming growth factors

DESCRIPTION: (adapted from the investigator's abstract) The major goal of this proposal is to define the role of the protein SKI in human melanomas. SKI expression is highly elevated in melanomas compared to normal melanocytes. Their preliminary data demonstrates that SKI participates in the TGF-B signaling pathway and in the DNA damage response. He has found that SKI physically associates with the transcriptional co-activator proteins Smad2 and Smad3, two members of the TFG-B signaling pathway. In addition, forced expression of SKI results in inactivation of G1 checkpoints downstream from the protein p53. He proposes to determine the role of SKI in the TGF-B pathway and to determine the molecular mechanism(s) by which SKI interferes with the DNA-damage response in melanocytes and melanoma cells. Specifically, he will: (1) Define the molecular and biological activities of SKI in the TGF-G pathway by a) analyzing the activities of SKI/Smads complexes on TFG-B responsive promoters; b) determining whether SKI perturbs hetero-oligomer formation between Smad2 and Smad3 and the common-mediator Smad4; c) determining whether forced expression of SKI converts TGF-B-sensitive, normal human melanocytes to TGF-B-resistance and/or whether SKI represses TGF-B-mediated gene activation in vivo. (2) Analyze the molecular mechanism(s) whereby SKI suppresses p21 (Waf-1/SDI/Cip/1) expression. For that, he will determine whether; a) SKI interferes with the DNA-binding activity of the protein p53; b) SKI disrupts association of p53 with transcriptional activators; c) SKI interferes with Smad and p53 activity on the p21 promoter. 3) Explore the long-term consequences of SKI activity by determining whether forced expression of SKI results in chromosome instability in DNA-damaged cells. He will analyze whether these cells show a) abnormal centrosome amplifications; b) changes in Cyclin-Cdk-Cdk-I complexes that predispose cells to unrestricted growth. The studies proposed should underscore the role of SKI as a potent oncogenic protein in human melanomas and lay down foundations for future intervention therapies.

描述：（改编自研究者的摘要）本研究的主要目标 该提案旨在定义蛋白质 SKI 在人类黑色素瘤中的作用。滑雪 与正常黑素细胞相比，黑色素瘤中的表达高度升高。 他们的初步数据表明 SKI 参与 TGF-B 信号通路和 DNA 损伤反应。他发现滑雪 与转录共激活蛋白 Smad2 和 Smad3，TFG-B 信号通路的两个成员。另外，强制 SKI 的表达导致下游 G1 检查点失活 蛋白质p53。他建议确定 SKI 在 TGF-B 途径中的作用并 确定 SKI 干扰的分子机制 黑色素细胞和黑色素瘤细胞中的 DNA 损伤反应。具体来说，他将： (1)定义SKI在TGF-G通路中的分子生物学活性 [0102] a)分析SKI/Smads复合物对TFG-B反应的活性 发起人； b) 确定 SKI 是否干扰异源低聚物的形成 Smad2 和 Smad3 以及共同介体 Smad4 之间； c) 确定是否 SKI 的强制表达将 TGF-B 敏感的正常人黑素细胞转化为 TGF-B 抗性和/或 SKI 是否抑制 TGF-B 介导的基因激活 体内。 (2)分析SKI抑制p21的分子机制 (Waf-1/SDI/Cip/1) 表达式。为此，他将决定是否； a) 滑雪 干扰蛋白质 p53 的 DNA 结合活性； b) 滑雪中断 p53 与转录激活因子的关联； c) SKI 干扰 Smad 和 p21 启动子上的 p53 活性。 3) 通过确定是否可以探索 SKI 活动的长期后果 SKI的强制表达导致DNA损伤的染色体不稳定 细胞。他将分析这些细胞是否表现出 a) 中心体异常 放大； b) 使细胞易感的 Cyclin-Cdk-Cdk-I 复合物的变化 到无限制的增长。 拟议的研究应强调 SKI 作为有效致癌物质的作用 人类黑色素瘤中的蛋白质并为未来的干预奠定基础 疗法。