Coordinated regulation of MAP kinase signaling by ubiquitination

通过泛素化协调调节 MAP 激酶信号传导

基本信息

批准号：
8223685
负责人：
Jillian Heyward Hurst
金额：
$ 2.61万
依托单位：
UNIV OF NORTH CAROLINA CHAPEL HILL
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-02-01 至 2012-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8223685
关键词：
Address Apoptosis Behavior Cardiac Cell Proliferation Cells Competence Complex Cullin Proteins Data Diabetes Mellitus Disease Environment Enzymes Eukaryota Eukaryotic Cell Event F Box Domain Feedback G-Protein-Coupled Receptors GTP-Binding Proteins Gene Expression Genetic Transcription Heterotrimeric GTP-Binding Proteins Immune System Diseases Immunoblotting In Vitro Libraries Link Lupus Malignant Neoplasms Mass Spectrum Analysis Mediating Membrane Protein Traffic Methods Mitogen-Activated Protein Kinase Kinases Mitogen-Activated Protein Kinases Modeling Morphology Mutate Mutation Myopathy Organism Output Parkinson Disease Partner in relationship Pathway interactions Pheromone Phosphorylation Phosphorylation Site Phosphotransferases Post-Translational Protein Processing Proteins Regulation Relative (related person)Role Saccharomyces cerevisiae Saccharomycetales Scaffolding Protein Series Signal Pathway Signal Transduction Signal Transduction Pathway Signaling Protein Site Specificity Substrate Specificity System Testing Ubiquitin Ubiquitin-Activating Enzymes Ubiquitin-Conjugating Enzymes Ubiquitination Virus Diseases Yeasts base combat human disease migration nervous system disorder protein protein interaction public health relevance research study response ubiquitin-protein ligase

项目摘要

DESCRIPTION (provided by applicant): Ubiquitination is a posttranslational modification that instigates proteasomal degradation of its target proteins. In recent years, the function of ubiquitination has expanded to include roles in membrane trafficking, protein-protein interactions, gene transcription, and kinase activation. Three enzymes mediate ubiquitination: the E1 ubiquitin-activating enzyme, the E2 ubiquitin-conjugating enzyme, and the E3 ubiquitin ligase, which determines the specificity of ubiquitination. Mutations of Skp1/Cullin/F-box E3 ubiquitin ligase complexes (SCF) have been linked to many human diseases, including multiple forms of cancer, immune disorders such as diabetes and lupus, neurological disorders like Parkinson's disease, viral infections, and cardiac myopathies. Our lab has recently demonstrated that a functional SCF complex is required for proper pheromone response in the budding yeast S. cerevisiae. The yeast pheromone response pathway is one of the best-characterized signal transduction pathways, consisting of a canonical G-protein coupled receptor (GPCR), heterotrimeric G- protein, and mitogen-activated protein kinase (MAPK) signaling cascade. Moreover, this signaling pathway has been used to identify multiple cell signaling mechanisms that are conserved in virtually all eukaryotes. We and others have demonstrated that the SCF complex is required for ubiquitination of multiple signaling components within the pheromone response pathway, including the G1 subunit Gpa1, the MAPK kinase Ste7, the scaffold protein Ste5, and the effector Far1. Further, we have recently generated data in our lab demonstrating that ubiquitination alters the selectivity of Ste7 activation of the downstream MAPKs Fus3 and Kss1. Based on these data, we hypothesize that SCF-mediated ubiquitination of Ste7 regulates its ability to selectively activate downstream signaling proteins. We further hypothesize that SCF is a master regulator of the MAPK signaling cascade, acting simultaneously on multiple pathway components to dictate overall pathway output. This hypothesis will be addressed through the following specific aims: Aim #1: Determine how ubiquitination modulates the activity and specificity of the pheromone pathway MAPKK Ste7. Aim #2: Systematically identify all proteins in the pheromone response pathway that are ubiquitinated by the SCF E3 ubiquitin ligase complex. The proposed studies will define how ubiquitination influences the signaling behavior of a target protein, determine the contribution of ubiquitination to overall signaling pathway output, and expand our understanding of how the highly-conserved MAPK cascade is regulated. PUBLIC HEALTH RELEVANCE: Cellular signaling pathways regulate how cells respond to their environment. Incorrect cellular signaling causes many human diseases including cancer, immune disorders like diabetes and lupus, and neurological disorders such as Parkinson's disease. This proposal aims to identify a new mechanism that regulates cellular signaling and possibly reveal new ways to modulate signaling pathways to combat disease.

描述（由申请人提供）：泛素化是一种翻译后修饰，可引发其靶蛋白的蛋白酶体降解。近年来，泛素化的功能已扩展到包括膜运输、蛋白质-蛋白质相互作用、基因转录和激酶激活中的作用。三种酶介导泛素化：E1 泛素激活酶、E2 泛素结合酶和 E3 泛素连接酶，它决定泛素化的特异性。 Skp1/Cullin/F-box E3 泛素连接酶复合物 (SCF) 的突变与许多人类疾病有关，包括多种癌症、糖尿病和狼疮等免疫疾病、帕金森病等神经系统疾病、病毒感染和心肌病。我们的实验室最近证明，芽殖酵母酿酒酵母中适当的信息素反应需要功能性 SCF 复合物。酵母信息素响应途径是最具特征的信号转导途径之一，由典型的 G 蛋白偶联受体 (GPCR)、异三聚体 G 蛋白和丝裂原激活蛋白激酶 (MAPK) 信号级联组成。此外，该信号传导途径已用于识别几乎所有真核生物中保守的多种细胞信号传导机制。我们和其他人已经证明，SCF 复合物是信息素响应途径内多个信号成分泛素化所必需的，包括 G1 亚基 Gpa1、MAPK 激酶 Ste7、支架蛋白 Ste5 和效应器 Far1。此外，我们最近在实验室中生成的数据表明，泛素化改变了下游 MAPK Fus3 和 Kss1 的 Ste7 激活的选择性。基于这些数据，我们假设 SCF 介导的 Ste7 泛素化调节其选择性激活下游信号蛋白的能力。我们进一步假设 SCF 是 MAPK 信号级联的主要调节器，同时作用于多个通路组件以决定整体通路输出。这一假设将通过以下具体目标得到解决：目标#1：确定泛素化如何调节信息素途径 MAPKK Ste7 的活性和特异性。目标#2：系统地识别信息素响应途径中被 SCF E3 泛素连接酶复合物泛素化的所有蛋白质。拟议的研究将定义泛素化如何影响靶蛋白的信号行为，确定泛素化对整体信号通路输出的贡献，并扩大我们对高度保守的 MAPK 级联如何调节的理解。公共卫生相关性：细胞信号通路调节细胞对其环境的反应。不正确的细胞信号传导会导致许多人类疾病，包括癌症、糖尿病和狼疮等免疫疾病以及帕金森病等神经系统疾病。该提案旨在确定一种调节细胞信号传导的新机制，并可能揭示调节信号传导途径以对抗疾病的新方法。