Mechanisms of cytosolic proteostasis in yeast

酵母细胞质蛋白稳态机制

• 批准号: 9763213
• 负责人: KEVIN ANTHONY MORANO
• 金额: $ 2.46万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCI CTR HOUSTON
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-04-16 至 2022-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9763213
• 关键词: ATPase Domain; Aging; Alzheimer' s Disease; Animal Model; Binding Sites; Biochemical; Biogenesis; Buffers; Cell Aging; Cell physiology; Cells; Chelating Agents; Chronic; Competence; Cysteine; Cytoplasmic Protein; Data; Diabetes Mellitus; Disease; Electron Transport Complex III; Ensure; Equilibrium; Experimental Models; Feedback; Future; Genetic Transcription; Glutathione; Goals; Guanine Nucleotide Exchange Factors; Health; Heat-Shock Response; Human; Huntington Disease; Inflammation; Investigation; Laboratories; Lead; Link; Maintenance; Mediating; Mediator of activation protein; Metabolic Diseases; Modeling; Modification; Molecular Chaperones; Nerve Degeneration; Neurodegenerative Disorders; Nucleotides; Oxidants; Oxidation-Reduction; Oxidative Stress; Oxides; Parkinson Disease; Pathway interactions; Play; Production; Proliferating; Proteins; Proteomics; Publishing; Quality Control; Reactive Oxygen Species; Reagent; Regulation; Reperfusion Injury; Research Proposals; Role; Saccharomyces cerevisiae; Saccharomycetales; Signal Transduction; Stress; Sulfhydryl Compounds; System; TXN gene; Testing; Therapeutic Intervention; Time; Tissues; Transcriptional Regulation; Work; Xenobiotics; Yeast Model System; Yeasts; adduct; base; biological adaptation to stress; cytotoxicity; experience; genetic approach; genetic manipulation; heat shock transcription factor; human disease; oxidation; oxidative damage; protein aggregation; protein misfolding; proteostasis; response; sensor; stress reactivity; therapeutic development; transcription factor; tumor growth; yeast genetics

Nearly 50 major diseases ranging from diabetes to neurodegenerative disorders including Alzheimer’s (AD), Parkinson’s (PD) and Huntington’s (HD) diseases have been linked to protein misfolding and aggregation. Cells grow and proliferate under the constant threat of damage from endogenous reactive oxygen species (ROS), exogenous oxidants and reactive electrophiles. Cytosolic protein cysteines are almost exclusively maintained in the reduced state, and cysteine oxidation caused by oxidative stress is predicted to result in significant misfolding and aggregation. However, relatively little is known about the consequences of redox imbalance on protein homeostasis (proteostasis). Furthermore, the roles of cellular reduction-oxidation (redox) buffering pathways, including the thioredoxin and glutathione systems, in maintaining cytosolic proteostasis are not well understood. We seek to understand the interplay between cytoprotective stress response pathways and the machinery employed to maintain proteostasis. Published and preliminary results detailed in the proposal lead us to hypothesize that induction of the cytoprotective heat shock response (HSR) by redox imbalance is mediated in part by a cysteine switch in the principal protein chaperone Hsp70 (Ssa1 in budding yeast) and that thiol redox buffering plays a significant role in maintenance of cytosolic proteostasis. The primary objectives of this renewal application are to determine the impacts of thiol-reactive stress on cytoplasmic protein biogenesis and protein quality control and to elucidate the regulatory interactions between oxidant and unfolded protein responses, through three distinct lines of investigation. In Specific Aim 1 we will define the mechanism by which the key molecular chaperone Ssa1/Hsp70 regulates the HSR through modulation of transcriptional activity by the master heat shock transcription factor Hsf1. Specific Aim 2 will investigate the consequences of thiol- reactive stress on Ssa1/Hsp70 activity and cellular functions, including how the Ssa1/Hsp70 redox switch regulates the HSR, and determine the roles of the highly conserved redox buffering systems in mediating thiol-reactive stress. In Specific Aim 3, we will determine the impacts of protein thiol modification on general cytosolic proteostasis using proteomic and genetic approaches. The work outlined in this proposal will reveal the mechanistic connections between cellular redox and protein quality control networks by exploiting the tractable yeast model system. These results in turn will guide future development of therapeutic interventions targeting ROS- and protein quality control-based disorders.

从糖尿病到神经退行性疾病的近50种主要疾病 包括阿尔茨海默氏症（AD），帕金森氏症（PD）和亨廷顿（HD）疾病 与蛋白质错误折叠和聚集有关。细胞在 内源性活性氧（ROS），外源性造成损害的恒定威胁 氧化剂和反应性电力。胞质蛋白质半胱氨酸几乎完全是 保持在降低的状态，由氧化应激引起的半胱氨酸氧化为 预测会导致重大错误折叠和聚集。但是，相对较少是 知道氧化还原不平衡对蛋白质稳态的后果 （proteostasis）。此外，细胞还原氧化（氧化还原）缓冲的作用 维持胞质的途径，包括硫氧还蛋白和谷胱甘肽系统 蛋白质症尚不清楚。我们试图了解 细胞保护应力反应途径和机械努力维护 蛋白毒酸。提案中详细介绍的已发布和初步结果使我们达到了 假设氧化还原诱导了细胞保护热冲击反应（HSR） 不平衡的部分是由主要蛋白链中的半胱氨酸开关介导的 HSP70（芽酵母中的SSA1），硫醇氧化还原缓冲在 维持胞质蛋白抑制剂。此更新应用程序的主要目标 确定硫醇反应胁迫对细胞质蛋白生物发生的影响 和蛋白质质量控​​制并阐明氧化剂之间的调节相互作用 和未展开的蛋白质反应，通过三种不同的研究线。具体 AIM 1我们将定义关键分子伴侣SSA1/HSP70的机制 通过主热量调节转录活性来调节HSR 冲击转录因子HSF1。具体目标2将研究硫醇的后果 SSA1/HSP70活性和细胞功能的反应性应力，包括如何 SSA1/HSP70氧化还原开关调节HSR，并确定高度的作用 保守的氧化还原缓冲系统在介导硫醇反应胁迫中。在特定的目标3中 我们将确定蛋白质硫醇修饰对一般胞质的影响 使用蛋白质组学和遗传方法的蛋白质静脉曲张。该提案中概述的工作 将揭示细胞氧化还原与蛋白质质量控​​制之间的机械连接 通过利用可牵引酵母模型系统的网络。这些结果反过来将指导 针对ROS和蛋白质质量的治疗干预措施的未来开发 基于控制的疾病。