C. elegans Model for Neurodegenerative Diseases of Aging

A.摘要 衰老是退行性疾病的主要风险因素，并与累积的蛋白质损伤和 细胞功能衰退。我们之前的工作证明，聚集倾向蛋白的表达 在线虫中，神经退行性疾病的模型会引发一连串的蛋白质损伤，导致 其他亚稳态蛋白质的错误折叠。使用一种计算方法，我们证明了存在风险的蛋白质 聚合不是随机性的，而是具有共同的序列元素，这些元素预测了它们的内在 亚稳性和聚集性。此外，各种神经元和非神经元中的错误折叠和聚集 组织在整个生命周期中并不是零星的，而是在线虫中更早的时候出现。 成年期与可诱导的细胞应激反应的稳健性急剧下降相吻合。在这 值得推广应用，我们建议测试的假设是蛋白质组的组成。和 急性和慢性疾病加速了衰老过程中可溶和不溶物种平衡的改变。 蛋白毒性应激，并通过选择性诱导蛋白平衡网络和寿命途径进行保护。这 将使用两个互补的模型系统进行演示：使用线虫的有机方法 为衰老提供了精确的模型，并有能力测试控制蛋白平衡和寿命的遗传路径， .和成人原代细胞和可诱导的多能细胞，以评估衰老蛋白质组的变化 控制这些过程的机制是保守的。目的是：(1)评估特异度 以及蛋白质组聚集在急、慢性蛋白毒性应激和衰老中的选择性。我们会 在线虫成虫和衰老的多个时间点进行蛋白质组学分析，并对可溶性的 在急性(热休克)和慢性(表达 聚谷氨酰胺。和tau)蛋白毒性应激。转变为聚集状态的蛋白质将通过以下方式进行验证 生成相应的一系列转基因蛋白-GFP报告系并用于评估折叠 在活体动物的不同间隔和组织中的过渡。人类比较蛋白质组学分析 来自不同年龄的捐赠者的原代细胞将揭示相同的蛋白质或 途径在溶解度和聚集性方面经历了类似的变化。蛋白质组数据将与 相应的一组RNA-SEQ数据，并用于开发模型以确定蛋白质组风险、失败或 可以在组织水平上评估保护，以建立对整个蛋白质组的组织理解 网络。(2)确定蛋白质组稳定性是否可以通过调节 蛋白质代谢网络和寿命途径。我们将决定对可溶的和 增强或抑制PN的不同臂的聚集蛋白质组。例如通过结构性激活 或抑制热休克反应和细胞器展开的蛋白质反应。同样，是 通过激活或抑制调节的寿命通路，对蛋白质组产生相同或不同的后果 通过热量限制、生殖系干细胞信号、胰岛素信号和热休克反应，以及‘(3) 建立应激和衰老蛋白质组的多维系统网络图。发展，发展 使用来自目标1和目标2的数据的蛋白质组动态随时间变化的可视图像。 蛋白质组和PN表达的档案数据。这张地图将被用来预测蛋白质， 受老化和压力影响并受伴侣网络和 PN.

A. Summary Aging is a major risk factor for degenerative diseases, and associated with cumulative protein damage and the decline of cellular function. Our previous work demonstrated that the expression of aggregation-prone proteins in C. elegans models of neurodegenerative disease initiates a cascade of protein damage that results in misfolding of other metastable proteins. Using a computation approach, we showed that proteins at-risk for aggregation are not randonri, but rather have in common sequence elements that predict their intrinsic metastability and tendency to aggregate. Moreover, misfolding and aggregation in various neuronal and nonneuronal tissues is not sporadic throughout lifespan, but rather occurs at a much earlier point in C. elegans adulthood coincident with a dramatic decline in the robustness of inducible cell stress responses. In this MERIT extension application, we propose to test the hypothesis that the composition of the proteome. and alterations in the balance of soluble and insoluble species during aging are accelerated by acute and chronic proteotoxic stress and protected by selective induction of proteostasis network and lifespan pathways. This will be demonstrated using two complementary model systems: an organismal approach using C. elegans that affords a precise model for aging and the ability to test genetic pathways that control proteostasis and lifespan, .and adult human primary cells and inducible pluripotent cells to assess whether changes in the aging proteome and mechanisms that control these processes are conserved. The Aims are: (1) Assessing the specificity and selectivity of proteome aggregation in acute and chronic proteotoxic stress and aging. We will perform a proteomic analysis at multiple points of C. elegans adulthood and aging, and quantify the soluble and aggregated fractions in animals challenged by acute (heat shock) and chronic (expression of polyglutamine. Aß, and tau) proteotoxic stress. Proteins that shift to the aggregated state will be validated by generating a corresponding series of transgenic protein-GFP reporter lines and used to assess folding transitions in different compartments and tissues in living animals. Comparative proteomic analysis of human primary cells from donors over a wide range of chronological age will reveal whether the same proteins or pathways undergo similar changes in solubility and aggregation. The proteomic data will be integrated with a corresponding set of RNA-seq data and used to develop models to establish whether proteomic risk, failure, or protection can be assessed at the tissue-level to establish an organismal understanding of proteome-wide networks. (2) Establishing whether proteome stability can be selectively altered by regulation of the proteostasis networif and lifespan pathways. We will determine the consequences to the soluble and aggregated proteome of enhancing or inhibiting different arms of the PN. for example by constitutive activation or inhibition of the heat shock response and the organellar unfolded protein responses. Likewise, are the consequences to the proteome the same or distinct, by activating or inhibiting the lifespan pathways regulated by caloric restriction, germline stem cell signaling, insulin-signaling, and the heat shock response, and '(3) Developing a multi-dimensional systems network map of the stressed and aging proteome. To develop a visual image of proteome dynamics over chronological age using data from Aims 1 and 2. together with archival data on expression of the proteome and the PN. This map will be used to predict the proteins, compartments, or tissues that are affected by aging and stress, and protected by chaperone networks and the PN.