Discovering small molecules activators of stress responsive signaling

项目主任/主要研究者（Lasl，Fitst，MItldle）：Morimoto，Richard I.，PL Project 4-Kelly，Jeffery W. 项目总结（见说明书）： 蛋白质稳态或蛋白质稳态的维持涉及平衡蛋白质的生物合成、折叠， 囊泡运输、降解等，我们假设这对健康老龄化至关重要。由于要求 在亚细胞区室上维持随着衰老和由于环境压力的蛋白质稳态变化， 应激反应信号通路已经进化为快速调节亚细胞蛋白质稳态网络 能力满足需求。在此，我们重点介绍了细胞报告基因的开发和利用 筛选发现可以选择性激活应激反应信号通路的小分子。一 提出了一种双发光报告细胞系，用于发现臂选择性未折叠蛋白反应 影响内质网中蛋白质稳态的激活剂。一种基于细胞的热休克反应 （影响胞质蛋白质稳态）激活剂报告基因筛选产生了许多小分子先导物 并且从臂选择性UPR激活剂筛选中也预期相同的结果。一个计划是概述辨别 应激反应信号通路激活这些先导物的选择性，以建立它们的治疗指数， 以确定所选激活因子的转录和蛋白质组学变化，并确定和验证 高等级激活器的目标。我们还建议利用小分子调节的不稳定的 结构域-FOXO转录因子融合体，以开发一种灵敏的和选择性的基于细胞的报告基因测定法， 最终筛选FOXO信号传导的小分子活化剂。FOXO影响新陈代谢， 蛋白质稳定控制选择性应激反应信号通路激活剂将使其成为可能， 该项目的其他研究人员将了解哪些亚细胞区室对 维持蛋白质稳态，促进健康衰老。细胞和动物中的细胞器选择性蛋白稳态增强 模型，再加上系统生物学表征的蛋白质稳态网络作为一个功能的老化 和活化剂处理应该提供一个明确的答案，关于细胞器特异性的影响， 蛋白质稳态对健康寿命的影响，个体无疾病的生命期-由于增强的 蛋白质组的适应性。 相关性（参见说明）： 在项目4中产生的分子及其在测试假设中的利用， 蛋白质组在生物体的寿命是至关重要的健康跨度代表了一个范式转变老化 迄今为止，研究主要集中在基因组不稳定性上。

Program Director/Principal Investigator (Lasl, Fitst, MItldle): Morimoto, Richard I., PL Project 4-Kelly, Jeffery W. PROJECT SUMMARY (See inslrucUons): The maintenance of protein homeostasis, or proteostasis, involves balancing protein biosynthesis, folding, vesicular trafficking, degradation, etc., which we hypothesize is critical for healthy aging. Since the demands on subcellular compartments to maintain proteostasis change with aging and due to environmental stresses, stress-responsive signaling pathways have evolved to quickly adjust subcellular proteostasis network capacity to meet demand. Herein, we focus on the development and utilization of cell-based reporter screens to discover small molecules that can activate stress-responsive signaling pathways selectively. A dual luminescence reporter cell line is proposed to discover arm-selective unfolded protein response activators affecting proteostasis in the endoplasmic reticulum. A prior cell-based heat shock response (influencing cytosolic proteostasis) activator reporter screen has generated numerous small molecule leads and the same is expected from the arm-selective UPR activator screen. A plan is outlined to discern the stress responsive signaling pathway activation selectivity of these leads, to establish their therapeutic index, to identify the transcriptional and proteomic changes of select activators, and to identify and validate the target(s) of the highly ranked activators. We also propose to utilize small molecule-regulated destabilized domain-FOXO transcription factor fusions to deveiop a sensitive and selective cell-based reporter assay for eventual screening of small molecule activators of FOXO signaling. FOXO influences metabolic and proteostatic control. Selective stress-responsive signaling pathway activators will make it possible for the other investigators in this program project to learn which subcellular compartments are most important to maintain proteostasis in for healthy aging. Organelle-selective proteostasis enhancement in cell and animal models, coupled with the systems biology characterization of the proteostasis network as a function of aging and activator treatment should provide a clear answer regarding the influence of organelle-specific proteostasis on healthspan, the period of life where individuals are disease free-owing to the enhanced fitness of the proteome. RELEVANCE (See inslrucUons): The molecules produced in Project 4 and their utilization in testing the hypothesis that maintenance of the proteome over the lifespan of an organism is critical for healthspan represents a paradigm shift in aging research, which heretofore has largely focused on genome instability.