Uncovering an Enzymatic Program that Drives Physiological and Pathological Amyloid Formation.

发现驱动生理和病理淀粉样蛋白形成的酶程序。

• 批准号: 10571966
• 负责人: Michael Bokros
• 金额: $ 9.34万
• 依托单位: UNIVERSITY OF MIAMI SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-01-01 至 2024-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10571966
• 关键词: Age; Aging; Alzheimer' s Disease; Amyloid; Amyloid Fibrils; Amyloid beta-Protein; Amyloid deposition; Amyloid fibers; Biological Process; Biology; Cells; Complement; Data; Dedications; Disease; Disease model; Enzymes; Equilibrium; Family; Link; Liquid substance; Modeling; Organism; Parkinson Disease; Pathologic; Phase; Phase Transition; Physical condensation; Physiological; Poly(A)+ RNA; Process; Property; RNA; RNA Degradation; RNA Folding; Regulation; Research; Ribosomal RNA; Solid; Stimulant; Tail; Testing; Toxic effect; active control; alpha synuclein; amyloid formation; amyloidogenesis; beta pleated sheet; cell assembly; cofactor; combat; exhaust; exosome; genetic manipulation; innovation; novel strategies; nucleotidyltransferase; programs; protein aggregation; protein folding; proteotoxicity

Project Summary Amyloids are β-sheet rich aggregates that accumulate in various proteinopathies. This correlation has led to the association of amyloids with the diseased state. However, organisms across biology utilize amyloids without any apparent detrimental effects. This raises the fundamental question; how do cells assemble non-toxic amyloids as needed? Our lab uncovered an inducible program of physiological amyloidogenesis that converts Nucleoli into Amyloid-bodies. While investigating these amyloid-enriched, solid-like condensates, we identified that Terminal End Nucleotidyltransferase 4b (TENT4b) stimulated the conversion of amyloidogenic liquid-to-solid phase transition. Our preliminary results indicate that TENTs catalyze unusually long poly(A)-rich tails to drive amyloidogenesis. These low-complexity RNA molecules act as linear polyanionic cofactors that stimulate amyloidogenesis. This activity is inhibited by the RNA exosome which degrades tailed RNA. In addition to physiological amyloidogenesis, TENTs also catalyze pathological amyloidogenesis which exhausts toxic oligomeric intermediates in Alzheimer’s and Parkinson’s disease models. Depletion of the RNA exosome that antagonizes TENTs, delays age-associated proteotoxicity in these disease models. These results suggest the following hypothesis for this K99:R00 application: The RNA tailing machinery drives amyloidogenesis to protect against toxic oligomeric intermediates. We plan to test this hypothesis by: Aim 1- investigating the mechanism that drives physiological amyloidogenesis and Aim 2- testing if this machinery protects against pathological amyloid toxicity. This research program reveals the provocative concept that cells possess enzymes dedicated to making non-toxic amyloids, highlighting that cellular amyloidogenesis is an actively controlled process. The cellular use of RNA to actively control protein folding bridges unrelated fields of research and offers new approaches to combat amyloid based disease.

项目摘要 淀粉样蛋白是一种富含β片状的聚集体，在各种蛋白质病中积聚。这种相关性导致了 淀粉样蛋白与疾病状态的关系。然而，整个生物界的生物利用淀粉样蛋白，而不是任何 明显的有害影响。这就提出了一个根本问题：细胞如何组装无毒的淀粉样蛋白？ 根据需要？我们的实验室发现了一种可诱导的生理性淀粉样蛋白发生程序，可将核仁转化为 变成淀粉样体。在研究这些富含淀粉样物质的固体状凝聚体时，我们发现 末端核苷酸转移酶4b(TENT4b)促进淀粉样变性液体向固体转化 相变。我们的初步结果表明，帐篷催化异常长的富含聚(A)的尾巴推动 淀粉样变。这些低复杂性的RNA分子充当线性多阴离子辅助因子，刺激 淀粉样变。这种活性被降解拖尾RNA的RNA外体抑制。除了……之外 生理性淀粉样变，帐篷也催化病理性淀粉样变，从而耗尽有毒物质 阿尔茨海默病和帕金森氏病模型中的寡聚中间体。耗尽RNA外切体 对抗帐篷，延缓这些疾病模型中与年龄相关的蛋白毒性。这些结果表明， 以下为K99：R00应用的假设：RNA拖尾机制驱动淀粉样蛋白发生保护 对抗有毒的低聚中间体。我们计划通过以下方式检验这一假设：目标1--研究机制 这推动了生理性淀粉样蛋白的发生和AIM 2-测试这一机制是否能防止病理性 淀粉样蛋白毒性。这项研究计划揭示了一个具有挑衅性的概念，即细胞拥有专门用于 到制造无毒的淀粉样蛋白，强调细胞淀粉样蛋白的发生是一个主动控制的过程。这个 细胞使用RNA来主动控制蛋白质折叠，为无关的研究领域架起了桥梁，并提供了新的 对抗基于淀粉样蛋白的疾病的方法。