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.

项目概要 淀粉样蛋白是富含 β-折叠的聚集体，在各种蛋白质病中积累。这种相关性导致了 淀粉样蛋白与疾病状态的关联。然而，跨生物学的生物体利用淀粉样蛋白而没有任何 明显的有害影响。这就提出了一个基本问题：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生理性淀粉样蛋白生成的诱导程序，可以将核仁转化为淀粉样蛋白。 进入淀粉样蛋白体。在研究这些富含淀粉样蛋白的固体状冷凝物时，我们发现 末端核苷酸转移酶 4b (TENT4b) 刺激淀粉样蛋白液体到固体的转化 相变。我们的初步结果表明，TENT 催化异常长的富含多聚 (A) 的尾巴来驱动 淀粉样蛋白生成。这些低复杂性 RNA 分子充当线性聚阴离子辅助因子，刺激 淀粉样蛋白生成。这种活性受到 RNA 外泌体的抑制，RNA 外泌体会降解带尾的 RNA。此外 生理性淀粉样蛋白生成，TENT 还催化病理性淀粉样蛋白生成，从而耗尽有毒物质 阿尔茨海默病和帕金森病模型中的寡聚中间体。 RNA 外泌体的耗尽 在这些疾病模型中拮抗 TENT，延缓与年龄相关的蛋白质毒性。这些结果表明 对于此 K99:R00 应用，有以下假设：RNA 加尾机制驱动淀粉样蛋白生成以保护 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 驱动生理性淀粉样蛋白生成和目标 2-测试该机制是否可以防止病理性淀粉样变 淀粉样蛋白毒性。该研究项目揭示了一个令人兴奋的概念，即细胞拥有专用酶 制造无毒淀粉样蛋白，强调细胞淀粉样蛋白生成是一个主动控制的过程。这 细胞利用 RNA 主动控制蛋白质折叠，将不相关的研究领域联系起来，并提供了新的 对抗基于淀粉样蛋白的疾病的方法。