Regulation of c-Raf-1 by Ras and Growth Factors

Ras 和生长因子对 c-Raf-1 的调节

• 批准号: 7162604
• 负责人: GURI TZIVION
• 金额: $ 25.77万
• 依托单位: WAYNE STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-01-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7162604
• 关键词: Attention; Binding; Biological; Cancerous; Cardiovascular Diseases; Cell Proliferation; Cell physiology; Cells; Complex; Development; Dimerization; Discipline; Disease; Family member; Frequencies; Growth; Growth Factor; Growth Factor Receptors; Human; In Vitro; Inflammation; Inhibitory Concentration 50; Laboratories; Length; MAP Kinase Gene; MEKs; Malignant - descriptor; Malignant Neoplasms; Mediating; Membrane; Methods; Molecular; Mutation; Nuclear; Numbers; Oncogenes; Oncogenic; Pathology; Pathway interactions; Peptides; Pharmacologic Substance; Phosphorylation; Phosphorylation Site; Phosphotransferases; Physiological Processes; Principal Investigator; Process; Proto-Oncogenes; Publishing; Ras/Raf; Rattus; Recruitment Activity; Regulation; Relative (related person); Research; Resources; Role; Signal Transduction; Site; Specificity; Stress; System; Therapeutic Agents; Virus; Work; base; design; desire; drug development; in vivo; inhibitor/antagonist; interest; metaplastic cell transformation; novel; novel strategies; programs; raf Kinases; receptor binding; response; tool; transforming virus; transmission process

The Ras-Raf-MAPK pathway regulates many physiological processes by transmitting signals from membrane- bound receptors to nuclear and cytoplasmic targets that coordinate cellular response to a variety of factors, such as growth, stress, survival and inflammation. Aberrations in this pathway result in abnormal growth and proliferation, and in many cases, cause malignant transformation. The high frequency of activating Ras mutations found in various human cancers, together with the well-documented role of Raf in numerous physiological processes, make the Ras-Raf-MAPK pathway a prime target for drug development for various cancers, inflammation and other aliments, c-Raf-1, a cellular protooncogene also found in transforming viruses, is the primary Ras effector for MAPK activation and is a major and indispensable part of the Ras-MAPK cascade. Although many laboratories have been studying Raf regulation, many aspects of this highly complex mechanism remain unknown. Published work by the applicant and preliminary results presented in this proposal help to unravel several of these aspects and provide a novel approach for inhibiting Raf activity. The objectives of the present application are to further the understanding of Raf regulation, focusing on specific roles of Ras and phosphorylation in Raf regulation, and to develop a useful in vivo Raf inhibitor based on a potent in vitro Raf inhibitor, described in this application. These objectives will be accomplished by pursuing the following three specific alms: 1. Characterize the role of Ras in the Raf-1 activation process. Attention will be given to distinguishing between the role of Ras in recruiting Raf to the membrane and displacing 14-3-3, and to the role of Ras-Ras and Raf-Raf dimerization in the activation process. 2. Determine the role of Raf-1 $471 and T481 sites in Rat regulation and function. This aim will be accomplished by examining the regulation of $471 and T481 phosphorylation and by evaluating the functional significance of their substitution and phosphorylation. 3. Characterize the mechanism underlying Raf inhibition by the Raf-1 inhibitor peptide, and identify peptide-delivery methods allowing inhibition of cellular Raf-1 in vivo. The proposed study will enhance our understanding of Raf regulation by providing molecular details on the role of Ras and newly identified Raf phosphorylation sites in Raf activation. In addition, the proposed study offers the prospect for developing an in vivo Raf inhibitor, which in addition to being a highly useful research tool, would provide a basis for developing therapeutic agents for diseases involving excessive cell proliferation such as cancer and inflammation. I

Ras-Raf-MAPK 通路通过传递来自膜的信号来调节许多生理过程。 将受体与细胞核和细胞质靶标结合，协调细胞对多种因素的反应，例如 生长、压力、生存和炎症。该途径的异常会导致异常生长和增殖， 在许多情况下，会导致恶变。激活 Ras 突变的频率很高 各种人类癌症，以及 Raf 在众多生理过程中的有据可查的作用，使得 Ras-Raf-MAPK 通路是多种癌症、炎症和其他疾病药物开发的主要靶点 c-Raf-1 是一种细胞原癌基因，也存在于转化病毒中，是食物中的主要 Ras 效应子 MAPK 激活是 Ras-MAPK 级联的主要且不可或缺的部分。虽然很多实验室 虽然一直在研究 Raf 调控，但这种高度复杂机制的许多方面仍然未知。已发表 申请人的工作和本提案中提出的初步结果有助于阐明其中几个方面 并提供了抑制 Raf 活性的新方法。本申请的目的是 进一步了解 Raf 调控，重点关注 Ras 和磷酸化的特定作用 Raf 调节，并在有效的体外 Raf 抑制剂的基础上开发有用的体内 Raf 抑制剂， 本申请中描述。这些目标将通过追求以下三个具体目标来实现 施舍： 1. 描述 Ras 在 Raf-1 激活过程中的作用。会注意区分 Ras 在将 Raf 募集至膜并置换 14-3-3 中的作用，以及 Ras-Ras 和 Ras 的作用之间 激活过程中 Raf-Raf 二聚化。 2. 确定 Raf-1 $471 和 T481 位点在大鼠中的作用 调节和功能。这一目标将通过审查 $471 和 T481 的监管来实现 磷酸化并评估其取代和磷酸化的功能意义。 3. 表征 Raf-1 抑制肽抑制 Raf 的机制，并鉴定肽递送 允许体内抑制细胞 Raf-1 的方法。拟议的研究将增强我们对 Raf 的了解 通过提供 Ras 作用的分子细节和 Raf 中新鉴定的 Raf 磷酸化位点来进行调控 激活。此外，拟议的研究为开发体内 Raf 抑制剂提供了前景，该抑制剂 除了作为一种非常有用的研究工具之外，还将为开发治疗药物提供基础 涉及细胞过度增殖的疾病，例如癌症和炎症。 我

项目成果

Identification of Raf-1 S471 as a novel phosphorylation site critical for Raf-1 and B-Raf kinase activities and for MEK binding.

• DOI: 10.1091/mbc.e05-02-0090
• 发表时间: 2005-08
• 期刊: Molecular biology of the cell
• 影响因子: 3.3
• 作者: Jun Zhu;V. Balan;Agnieszka Bronisz;Karina Balan;Hengrui Sun;Deborah T Leicht;Zhijun Luo;J. Qin;J. Avruch;G. Tzivion

Special issue on mitogen-activated protein kinases: New insights into regulation, function and role in human disease.

关于丝裂原激活蛋白激酶的特刊：对人类疾病中的调节、功能和作用的新见解。

• DOI: 10.1016/j.bbamcr.2007.03.005
• 发表时间: 2007
• 期刊: Biochimica et biophysica acta
• 作者: Tzivion,Guri