Elucidating the impact of FIC-1/FICD-mediated AMPylation on polyglutamine aggregation dynamics and toxicity

阐明 FIC-1/FICD 介导的 AMPylation 对聚谷氨酰胺聚集动力学和毒性的影响

• 批准号: 10464265
• 负责人: Kate Matthys Van Pelt
• 金额: $ 3.95万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10464265
• 关键词: Adenosine Monophosphate; Affect; Aging; Alleles; Animals; Attenuated; Biochemical; Biological Assay; Buffers; CRISPR interference; Caenorhabditis elegans; Cells; Cellular Structures; Chemicals; Data; Development; Disease; Disease model; Excision; Failure; Family; General Population; Genes; Genetic; Goals; Heat-Shock Proteins 70; Human; Huntington Disease; Huntington gene; In Vitro; Inclusion Bodies; Individual; Inherited; Knock-out; Knowledge; Length; Link; MJD1 protein; Machado-Joseph Disease; Maintenance; Mediating; Mediator of activation protein; Molecular; Molecular Chaperones; Mutagenesis; Neurodegenerative Disorders; Neurons; Orthologous Gene; Pathogenicity; Pathologic; Pathway interactions; Patients; Physiological; Post-Translational Protein Processing; Post-Translational Regulation; Prevalence; Process; Proteins; Quality Control; RNA Interference; Regulation; Reporting; Research; Role; Signal Pathway; Solubility; Stress; Sum; Techniques; Testing; Therapeutic; Therapeutic Intervention; Tissues; Toxic effect; Trinucleotide Repeat Expansion; Type 1 Spinocerebellar Ataxia; Work; arm; base; biological adaptation to stress; disease-causing mutation; follow-up; functional decline; human embryonic stem cell; in vitro Model; knock-down; misfolded protein; mutant; neuron loss; novel; overexpression; polyglutamine; protein aggregation; protein function; protein misfolding; proteostasis; response; stem cells; targeted treatment

PROJECT SUMMARY Huntington’s disease (HD) and spinocerebellar ataxia type 3 (SCA3) are inherited aging-associated diseases that have a devastating impact on patients and family caretakers relative to their prevalence in the general population. These conditions belong to a family of polyglutamine (polyQ) expansion diseases caused by mutations resulting in the pathological expansion of trinucleotide (CAGn) repeats in distinct genes. Increases in CAG repeat length give rise to proteins containing aberrantly expanded polyQ tracts, which interfere with normal protein function and promote misfolding. Toxicity in these diseases is thought to arise in part from the formation of pathological inclusion bodies comprised of aberrantly conformed mutant proteins, a hallmark observed in numerous aging-associated neurodegenerative diseases. Despite extensive efforts to decipher the mechanisms underlying toxicity in polyQ diseases, however, little progress has been made towards identifying targets for therapeutic intervention. Recently, the post-translational modification (PTM), AMPylation, has emerged as a novel regulator of HSP70 family chaperones, crucial components of the cell’s protein quality control machinery that buffer against protein misfolding stress. Protein AMPylation is carried out by the fic-type AMPylase, FICD in humans, and its ortholog FIC-1, in C. elegans, respectively. Work in our lab has established that FIC-1-mediated AMPylation directly alters polyQ aggregation dynamics and toxicity. Further, my preliminary data as presented in this proposal identifies fic-1 deficiency as sufficient to rescue survival of C. elegans expressing aggregation-prone polyQs during development in a polyQ length-dependent manner. Taken together, these findings suggest that the loss of FIC- 1/FICD-mediated AMPylation bolsters proteostasis network capacity to alleviate toxicity induced by polyQ protein aggregation. This project will utilize cross-disciplinary approaches to generate a holistic characterization of FICD/FIC-1- mediated AMPylation in polyQ diseases. To this end, I will harness the powerful genetics of C. elegans to uncover novel pathway(s) that promote survival in the face of pathogenic polyQ aggregation (Aim 1). In tandem, I will employ functional assays in neurons derived from HD and SCA3 patient stem cells to profile how FICD activity affects polyQ aggregation and toxicity in these disease models (Aim 2). The results of these studies will advance our knowledge of how AMPylation regulates proteostasis in polyQ diseases. The ultimate goal of my research is to capitalize on these findings to develop translatable therapeutic approaches for aging-associated diseases.

项目概要 亨廷顿病 (HD) 和脊髓小脑性共济失调 3 型 (SCA3) 是遗传性衰老相关疾病 相对于一般情况而言，这对患者和家庭护理人员具有毁灭性影响 人口。这些病症属于由以下原因引起的聚谷氨酰胺 (polyQ) 扩张疾病家族： 突变导致不同基因中三核苷酸（CAGn）重复的病理性扩展。增加于 CAG 重复长度会产生含有异常扩增的 PolyQ 束的蛋白质，从而干扰正常的 蛋白质功能并促进错误折叠。这些疾病的毒性被认为部分是由形成的 由异常构象的突变蛋白组成的病理包涵体，这是在 许多与衰老相关的神经退行性疾病。尽管为破译机制付出了巨大的努力 然而，在确定 PolyQ 疾病的潜在毒性目标方面进展甚微。 治疗干预。 最近，翻译后修饰 (PTM) AMPylation 已成为 HSP70 的新型调节剂 家族伴侣，细胞蛋白质质量控​​制机制的重要组成部分，可缓冲蛋白质 错误折叠压力。蛋白质 AMP 化由人类的 fic 型 AMP 化酶、FICD 及其直系同源物进行 FIC-1，分别在秀丽隐杆线虫中。我们实验室的工作已证实 FIC-1 介导的 AMPylation 直接改变 PolyQ 聚集动力学和毒性。此外，我在本提案中提供的初步数据表明 fic-1缺陷足以挽救表达易聚集的polyQs的秀丽隐杆线虫的存活 以polyQ长度依赖的方式发展。总而言之，这些发现表明 FIC 的损失 1/FICD 介导的 AMPylation 增强了蛋白质稳态网络能力，以减轻 PolyQ 蛋白诱导的毒性 聚合。 该项目将利用跨学科方法来生成 FICD/FIC-1- 的整体特征 PolyQ 疾病中介导的 AMPylation。为此，我将利用秀丽隐杆线虫强大的遗传学来揭示 在面对致病性 PolyQ 聚集时促进生存的新途径（目标 1）。同时，我将 对 HD 和 SCA3 患者干细胞衍生的神经元进行功能测定，以分析 FICD 活性如何 影响这些疾病模型中的 polyQ 聚集和毒性（目标 2）。这些研究结果将推进 我们对 AMPylation 如何调节 PolyQ 疾病中蛋白质稳态的了解。我研究的最终目标是 利用这些发现来开发针对衰老相关疾病的可转化治疗方法。