The Role of RNA in Tau Aggregation

RNA 在 Tau 聚集中的作用

基本信息

批准号：
9759683
负责人：
Evan T Lester
金额：
$ 3.35万
依托单位：
UNIVERSITY OF COLORADO
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-08-15 至 2023-08-14
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9759683
关键词：
Address Affect Alzheimer&apos s Disease Amyloid beta-Protein Autopsy Binding Biochemical Biological Models Brain Cause of Death Cell Line Cell model Cells Cellular Assay Cellular Stress Cytoplasm Cytoplasmic Granules Data Disease Electron Microscopy Fluorescence Fluorescent in Situ Hybridization Frontotemporal Dementia Frontotemporal Lobar Degenerations Health Human Immunoprecipitation In Situ Hybridization In Vitro Incubated Inflammation Inflammatory Knock-out Lead Link MAPT gene Measures Messenger RNA Microtubule Stabilization Microtubules Modeling Molecular Conformation Mus Mutation Nerve Degeneration Neurodegenerative Disorders Neurons Nuclear Oxidative Stress Patients Pharmacology Physiological Play Prostaglandins Proteins Protocols documentation RNA RNA Binding RNA Stability RNA-Protein Interaction Ribonucleases Ribosomal RNA Role Seeds Small Interfering RNA Small Nuclear RNA Specificity Stress Tauopathies Testing Therapeutic Toxic effect Transcript Transgenic Mice United States Untranslated RNA Virus Diseases biological adaptation to stress chronic traumatic encephalopathy cofactor crosslink experimental study extracellular genetic approach in vivo induced pluripotent stem cell insight neuroinflammation neurotoxic novel therapeutic intervention paired helical filament recruit response sarkosyl single molecule stress granule stressor tau Proteins tau aggregation tau interaction transcriptome sequencing

项目摘要

PROJECT SUMMARY: Tauopathies are a group of neurodegenerative diseases characterized by aggregates of the Microtubule Associated Protein Tau (tau) found in the brains of patients on autopsy. These disorders include Alzheimer's disease (AD), chronic traumatic encephalopathy (CTE), and frontotemporal dementia (FTD). AD alone is the 6th leading cause of death in the US (affecting more than 5.7 million), no cure is currently available, and the number of patients is expected to substantially increase in the coming years. Tauopathies can be caused by mutations in tau that promote its aggregation (as in FTD) or by extracellular stressors that trigger tau aggregation (as in AD and CTE). How extracellular stressors lead to intracellular tau aggregation is unknown. A number of recent observations indicate that stress granules (SGs), a type of cytosolic RNA and protein assembly that forms in response to cellular stress, might be involved in the formation and persistence of tau aggregates and manipulating SGs could indicate new therapeutic strategies. I propose a model where cellular stressors (e.g., neuroinflammation, viral infection, amyloid-b) promote the formation of SGs that recruit tau. SGs create high local concentrations of tau and RNA that nucleate and stabilize tau aggregates and contribute to their toxicity. This model is supported by in vitro and in vivo evidence suggesting that RNA promotes tau aggregation, RNA is sequestered into tau aggregates in AD patient brains, and that reducing SG formation decreases tau toxicity. My preliminary data shows that stress granules induced by the neuroinflammatory compound, prostaglandin J2, colocalize with tau. I have also shown by electron microscopy and thioflavin T fluorescence that incubating RNA with tau in vitro causes the formation of tau aggregates made up of paired helical filaments that contain RNA. Finally, I have shown by RNAseq and by single molecule fluorescence in situ hybridization (smFISH) that in vivo tau aggregates contain a diversity of RNAs (rRNAs, mRNAs, snRNAs, and lncRNAs) and some RNAs are more enriched than others. Aim 1 of this proposal will identify and manipulate the levels of RNAs that are bound by tau in unaggregated and aggregated states in disease relevant model systems. Successful completion of this aim will suggest 1) what set of RNAs act as cofactors for tau aggregation, 2) whether the RNAs in tau aggregates are similar to SGs, and 3) whether sequestration of specific RNAs contributes to tau toxicity. Aim 2 of this proposal will manipulate SG formation and RNA stability and then measure how these manipulations influence tau aggregation. Results of this aim will determine what role RNA and SGs play in the formation and persistence of tau aggregates. Broadly, this proposal aims to test the hypothesis that SGs link extracellular stress and intracellular tau aggregation with the hope of identifying new therapeutic strategies to treat debilitating neurodegenerative diseases such as AD.

项目摘要：Tau蛋白病是一组神经退行性疾病，其特征是以下物质的聚集：尸检患者大脑中发现的微管相关蛋白 Tau (tau)。这些疾病包括阿尔茨海默病 (AD)、慢性创伤性脑病 (CTE) 和额颞叶痴呆 (FTD)。广告仅此一项就成为美国第六大死因（影响超过 570 万人），目前尚无治愈方法，预计未来几年患者数量将大幅增加。 tau 蛋白病可能是由促进其聚集的 tau 蛋白突变（如 FTD）或由触发 tau 蛋白聚集的细胞外应激源（如 AD 和 CTE）。细胞外应激源如何导致细胞内 tau 蛋白聚集尚不清楚。最近的一些观察表明，应力颗粒 (SGs)，一种响应细胞应激而形成的胞质 RNA 和蛋白质组装体，可能参与其中 tau 聚集体的形成和持久性以及操纵 SG 可能预示着新的治疗方法策略。我提出了一个模型，其中细胞应激源（例如神经炎症、病毒感染、淀粉样蛋白-b）促进招募 tau 蛋白的 SG 的形成。 SG 产生局部高浓度的 tau 蛋白和成核 RNA 并稳定 tau 蛋白聚集体并增加其毒性。该模型得到体外和体内的支持有证据表明 RNA 促进 tau 聚集，在 AD 患者中 RNA 被隔离在 tau 聚集体中大脑中，减少 SG 形成可降低 tau 毒性。我的初步数据表明，神经炎症化合物诱导的应激颗粒，前列腺素 J2，与 tau 共定位。我还通过电子显微镜和硫代黄素 T 荧光显示在体外将 RNA 与 tau 蛋白一起孵育会导致由成对的螺旋丝组成的 tau 蛋白聚集体的形成含有RNA的。最后，我通过RNAseq和单分子荧光原位杂交证明了 (smFISH) 体内 tau 聚集体含有多种 RNA（rRNA、mRNA、snRNA 和 lncRNA），并且一些 RNA 比其他 RNA 更富集。该提案的目标 1 将识别和操纵 tau 结合的 RNA 水平疾病相关模型系统中的未聚合和聚合状态。这一目标的顺利完成将建议 1) 哪组 RNA 作为 tau 聚集的辅助因子，2) tau 聚集中的 RNA 是否相似 SGs，以及 3) 特定 RNA 的隔离是否会导致 tau 毒性。该提案的目标 2 将操纵 SG 形成和 RNA 稳定性，然后测量这些操纵如何影响 tau 聚合。这一目标的结果将决定 RNA 和 SG 在形成和持续存在中发挥什么作用。 tau 聚集体。从广义上讲，该提案旨在检验 SG 将细胞外应激与细胞外应激联系起来的假设。细胞内 tau 蛋白聚集，希望找到新的治疗策略来治疗衰弱神经退行性疾病，例如 AD。