MITOGENIC AND ONCOGENIC REGULATION OF ERK/RSK SIGNALING

ERK/RSK 信号传导的有丝分裂和致癌调控

• 批准号: 2622577
• 负责人: JOHN BLENIS
• 金额: $ 40.76万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-02-08 至 2003-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2622577
• 关键词: 3T3 cells; HeLa cells; biological signal transduction; cell cell interaction; cell growth regulation; cytogenetics; enzyme activity; enzyme inhibitors; flow cytometry; gene expression; immunoprecipitation; laboratory mouse; mitogen activated protein kinase; mitogens; monoclonal antibody; oncogenes; phosphorylation; protein structure function; protein tyrosine phosphatase; regulatory gene; site directed mutagenesis; tissue /cell culture

Cytoplasmic and receptor tyrosine kinases, Ras small G proteins, heterotrimeric G proteins, and tumor promoting phorbol esters are among the major regulators of various signaling systems that modulate cell growth, differentiation and development. Inappropriate regulation can result in a variety of diseases due to improper differentiation/development or malignant transformation. One of these signaling systems, often referred to as the MAP kinase pathway, is composed of a regulated serine/threonine kinase module, downstream of the c-Ras protooncogene. Presented simply, this module consists of the protooncogene c-Raf - greater than the dual-specificity kinase MEK - greater than the mitogen-activated kinase, ERK. An ERK-activated kinase, RSK, lies downstream of the ERKs. ERK and RSK translocate to the nucleus in response to mitogens, providing a mechanism for signal transduction from the cytoplasm to nucleus. The research proposed in this application addresses issues regarding the regulation of ERK/RSK activation and downstream signaling. The first objective is to characterize novel inputs into the ERK pathway, downstream of Ras, Raf and MEK, that play an important role in the activation kinetics of ERK and RSK, and subsequent nuclear signaling. An activity that is inactivated upon mitogen stimulation and that negatively regulates the ERKs has been previously identified. Experiments are proposed to biochemically or molecularly identify ERK phosphatases or noncatalytic inhibitors that exhibit the properties of this inhibitor. Candidate molecules will also be examined. The second objective of this proposal is to thoroughly characterize the regulation and biological function of RSK, about which little is known. Experiments proposed to characterize RSK include: structure/function of analysis, identification and mutational analysis of novel, ERK-mediated, and auto phosphorylation sites, characterization of dominant-negative RSK alleles and either effects of downstream targets, the mechanism of RSK nuclear translocation, the regulation of gene expression by RSK, and the role of RSK in regulating cell proliferation. The third major objective of this proposal characterizes nuclear signal transduction by ERK and RSK. The focus of this aim will be on the characterization of c-Fos phosphorylation by ERK and RSK, and the subsequent recruitment of a novel Fos kinase activity. Experiments described are aimed at identifying the Fos kinase using biochemical or molecular approaches. Candidate molecules will also be examined.

细胞质和受体酪氨酸激酶，Ras小G蛋白， 异源三聚体G蛋白和促进肿瘤的佛波酯是其中之一。 调节细胞的各种信号系统的主要调节器 生长、分化和发育。不适当的监管可以 因使用不当而导致多种疾病 分化/发展或恶性转化。 其中一 信号系统，通常被称为MAP激酶途径， 由调节的丝氨酸/苏氨酸激酶模块组成，下游为 c-Ras原癌基因 简单地说，该模块包括 原癌基因c-Raf -大于双特异性激酶MEK - 比丝裂原活化激酶ERK更强。 ERK激活的 激酶RSK位于ERK的下游。 ERK和RSK易位至 细胞核对有丝分裂原的反应， 从细胞质到细胞核的转导。该研究在 本申请解决了关于ERK/RSK调节的问题 激活和下游信号传导。 第一个目标是表征ERK的新输入 Ras、Raf和MEK的下游通路，在 ERK和RSK的活化动力学以及随后的核 信号 一种在有丝分裂原刺激后失活的活性， 负调节ERK的基因已经被发现。 实验提出了生物化学或分子鉴定ERK 磷酸酶或非催化抑制剂，其表现出 这种抑制剂。还将检查候选分子。 本提案的第二个目标是彻底描述 RSK的生物学功能和调控机制尚不清楚。 提出表征RSK的实验包括： 分析、鉴定和突变分析新的ERK介导的， 和自身磷酸化位点，显性阴性的表征 RSK等位基因和下游靶点的作用， RSK核转位，RSK对基因表达的调节， RSK在调节细胞增殖中的作用。 该提案的第三个主要目标是核信号 通过ERK和RSK转导。 这一目标的重点将是 ERK和RSK对c-Fos磷酸化的表征， 随后募集新的Fos激酶活性。 实验 所描述的目的是使用生物化学或生物化学方法鉴定Fos激酶， 分子方法 还将检查候选分子。