Endoplasmic Reticulum Thiol Redox State and Unfolded Protein Response in Aging

个人描述(申请人提供)：我的长期目标是了解衰老的基本机制，我坚定地致力于作为一名独立研究人员的学术生涯。这份建议描述了一项为期5年的综合培训计划，旨在促进我的职业发展，并过渡到老龄化研究领域的终身教职。该提案的指导阶段将在Vadim Gladyshev博士和Gary Ruvkun博士的共同指导下进行，Vadim Gladyshev博士是氧化还原生物学和比较基因组学方面的知名专家，Gary Ruvkun博士是衰老、遗传学和新陈代谢生物学的先驱研究员。此外，由约瑟夫·洛斯卡尔佐博士、Gokhan Hotamisligil博士和廖荣立博士组成的由内质网展开蛋白质应激反应、氧化还原信号和荧光激活细胞分选分析方面专业知识的知名医学科学家组成的顾问小组将提供进一步的科学和职业指导。计划的职业发展活动将在布里格姆妇女医院和哈佛医学院进行，这两个医院提供了良好的研究和培训环境。研究计划：内质网应激和蛋白质错误折叠已被证明在衰老和各种与年龄相关的疾病的发病机制中发挥重要作用，如糖尿病、癌症和神经退行性变。细胞通过激活一种称为未折叠蛋白反应(UPR)的进化保守的保护机制来适应错误折叠蛋白在内质网中的积累。这个信号通路通过降解错误折叠的蛋白质、抑制翻译、促进蛋白质折叠和分泌来恢复ER的动态平衡。尽管UPR功能障碍越来越被认为是年龄相关疾病的病理生理学因素，但UPR信号在调节寿命方面的作用尚不清楚。这项提议将检验这样一种假设，即无论是从药物上还是从基因上调节UPR信号，都可以激活保护性细胞应激反应，并介导寿命延长。我们的初步数据表明，由于内质网中个别蛋白质折叠和成熟因子的选择性失活而导致的“温和的”内质网应激，导致UPR信号的结构性上调，从而延长了萌芽酵母的寿命。我们还发现，这些ER/分泌途径突变体的寿命延长依赖于功能性ER应激传感器蛋白Ire1p，并与ER过氧化有关，这表明ER中的氧化还原状态与UPR信号密切相关，是酿酒酵母寿命的重要决定因素。基于这些发现，我们建议解决以下具体问题：(I)UPR和ER氧化还原状态调节长寿的机制是什么？(Ii)内质网中蛋白质的折叠能力和氧化还原状态是如何随年龄变化的？(3)能否用小分子化合物对UPR进行调节，以提高其抗内质网应激能力，调节衰老过程？

DESCRIPTION (provided by applicant): My long-term goals are focused on understanding the basic mechanisms of aging and I am strongly committed to pursuing an academic career as an independent investigator. This proposal describes a comprehensive 5-year training program for my career development and transition to a tenure-track faculty position in the field of aging research. The mentored phase of the proposal will be carried out under the mentorship of Dr. Vadim Gladyshev, a well-established expert in redox biology and comparative genomics, and the co-mentorship of Dr. Gary Ruvkun, a pioneering researcher in the biology of aging, genetics and metabolism. Additionally, an advisory panel of established medical scientists with expertise in the ER unfolded protein stress response, redox signaling, and fluorescence activated cell sorting analysis consisting of Drs. Joseph Loscalzo, Gokhan Hotamisligil and Ronglih Liao will provide further scientific and career guidance. The planned career development activities will be carried out at the Brigham and Women's Hospital and Harvard Medical School, which provide an excellent research and training environment. Research plan: ER stress and protein misfolding have been shown to play an important role in aging and pathogenesis of various age-related diseases, such as diabetes, cancer and neurodegeneration. Cells adapt to accumulation of misfolded proteins in the ER by activating an evolutionary conserved protective mechanism known as the unfolded protein response (UPR). This signaling pathway restores ER homeostasis by degrading misfolded proteins, inhibiting translation, and facilitating protein folding and secretion. Although UPR dysfunction is increasingly recognized as a contributing factor to the pathophysiology of age-related diseases, the role of UPR signaling in regulating lifespan is not known. This proposal will test the hypothesis that modulating UPR signaling, either pharmacologically or genetically, can activate protective cellular stress responses and mediate lifespan extension. Our preliminary data demonstrate that constitutive up-regulation of the UPR signaling due to "mild" ER stress caused by selective inactivation of individual protein folding and maturation factors in the ER leads to increased longevity in budding yeast. We also found that extended lifespan in these ER/secretory pathway mutants is dependent on functional ER stress sensor protein, Ire1p, and is associated with ER hyperoxidation, suggesting that redox status in the ER is closely interlinked with the UPR signaling and is an important determinant of S. cerevisiae lifespan. Building upon these findings, we propose to address the following specific questions: (i) What are the mechanisms by which UPR and ER redox state regulate longevity? (ii) How protein folding capacity and redox state in the ER change with age? (iii) Can modulation of the UPR with small molecule compounds be used to improve ER stress resistance and regulate aging process?