MAP Kinase Regulation of Substrate Proteins

底物蛋白的 MAP 激酶调节

• 批准号: 7668422
• 负责人: Kerry Kornfeld
• 金额: $ 25.36万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-01-01 至 2011-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7668422
• 关键词: Address; Affinity; Animals; Area; Binding; Biochemical; Biological Assay; Caenorhabditis elegans; Cell Proliferation; Cells; Complex; DNA Binding; Development; Disease; Docking; Enzymes; Equilibrium; Extracellular Signal Regulated Kinases; Gene Expression; Gene Targeting; Genetic Techniques; Genetic Transcription; Goals; Human; Knowledge; Laboratories; Language; Lead; Lobular Neoplasia; Logic; MAP Kinase Signaling Pathways; MEKs; Malignant Neoplasms; Mediating; Medical Research; Methods; Mitogen-Activated Protein Kinases; Modeling; Mutation; NuRD complex; Nucleosomes; Oncogenic; Pathway interactions; Phosphorylation; Proliferating; Proteins; Ras Signaling Pathway; Ras/Raf; Reagent; Recruitment Activity; Regulation; Repression; Research; Research Personnel; Signal Pathway; Signal Transduction; Signaling Protein; Site; Systems Analysis; Techniques; Testing; Transcription Coactivator; Vertebrates; base; chromatin remodeling; effective therapy; elk-1 protein; gene repression; histone methyltransferase; innovation; neoplastic cell; novel; novel therapeutics; programs; transcription factor; tumor

DESCRIPTION (provided by applicant): The Ras - ERK MAP kinase signaling pathway is critical for establishing cell fates during development. Importantly, mutations that activate the Ras pathway are a prevalent cause of human tumors. A major gap in our current understanding of this pathway is how activation of ERK alters the balance in gene expression to promote cell proliferation. Our long term goal is to understand how the Ras signaling pathway switches the activity of transcription factors so that they promote cell proliferation. We will address this by analyzing transcription factors that respond to Ras-mediated signaling in C. elegans and vertebrates. Understanding how the Ras pathway controls gene expression in development and disease in an important objective of medical research, since the information may lead to new and effective therapies for tumors caused by activated Ras signaling. Our preliminary results have defined exciting new mechanisms for the regulation of the LIN-1 transcription factor by Ras-mediated signaling and support two innovative hypotheses. (1) The LIN-1 transcription factor is post translationally modified by SUMO. Sumoylated LIN-1 represses transcription by interacting with MEP-1, DAS-1 and MAS-1, proteins involved in chromatin remodeling. (2) Activated ERK switches LIN-1 from a sumoylated, transcriptional represser that inhibits cell proliferation to a phosphorylated, transcriptional activator that induces cell proliferation. To test these hypotheses, we propose three specific aims. Aims 1 and 2: We will use biochemical techniques to define domains and specific residues of MEP-1, MAS-1 and DAS-1 that interact with LIN-1. We will characterize the relevance and specific functions of these interactions in intact animals. These studies will define the mechanisms of SUMO-mediated transcriptional repression and the significance of one DNA binding transcription factor recruiting three different transcriptional repressers. Aim 3: We will determine how ERK switches the activity of LIN-1. These studies will elucidate the mechanisms and logic of a switch that is critical for cell fate determination during development. The results of these studies will significantly advance the understanding of how ETS transcription factors are regulated, how SUMO mediates transcriptional repression, and how ERK promotes cell proliferation, and address critical gaps in our current knowledge of these important areas. This switch may also respond to oncogenic signaling pathways, and these studies will provide information that can result in new therapeutic strategies for blocking the proliferation of tumor cells in humans. Lay language: This research will reveal how tumor cells proliferate and suggest new strategies for treating human cancer.

描述（由申请方提供）：Ras-ERK MAP激酶信号通路对于在发育期间确定细胞命运至关重要。重要的是，激活Ras通路的突变是人类肿瘤的普遍原因。我们目前对这一通路的理解的一个主要差距是ERK的激活如何改变基因表达的平衡以促进细胞增殖。我们的长期目标是了解Ras信号通路如何转换转录因子的活性，从而促进细胞增殖。我们将通过分析C.线虫和脊椎动物。了解Ras通路如何控制发育和疾病中的基因表达是医学研究的一个重要目标，因为这些信息可能会导致新的有效治疗由激活的Ras信号转导引起的肿瘤。我们的初步研究结果已经确定了令人兴奋的新机制，通过Ras介导的信号转导调节LIN-1转录因子，并支持两个创新的假设。(1)LIN-1转录因子被SUMO后修饰。SUMO化的LIN-1通过与MEP-1、DAS-1和MAS-1（参与染色质重塑的蛋白质）相互作用来抑制转录。(2)活化的ERK将LIN-1从抑制细胞增殖的类小泛素化的转录阻遏物转换为诱导细胞增殖的磷酸化的转录激活物。为了验证这些假设，我们提出了三个具体目标。目的1和2：我们将使用生物化学技术来确定MEP-1，MAS-1和DAS-1与LIN-1相互作用的结构域和特定残基。我们将在完整的动物中描述这些相互作用的相关性和特定功能。这些研究将确定SUMO介导的转录抑制的机制和一个DNA结合转录因子招募三个不同的转录抑制因子的意义。目的3：我们将确定ERK如何切换LIN-1的活性。这些研究将阐明开关的机制和逻辑，这对于发育过程中细胞命运的决定至关重要。这些研究的结果将大大推进ETS转录因子是如何调节的理解，SUMO如何介导转录抑制，以及ERK如何促进细胞增殖，并解决我们目前对这些重要领域的知识的关键差距。这种开关也可能对致癌信号通路产生反应，这些研究将提供信息，可以导致新的治疗策略，用于阻断人类肿瘤细胞的增殖。这项研究将揭示肿瘤细胞如何增殖，并为治疗人类癌症提出新的策略。