Role of oligomeric TDP-43 aggregate intermediates in ALS and frontotemporal dementia

寡聚 TDP-43 聚合中间体在 ALS 和额颞叶痴呆中的作用

基本信息

批准号：
10553253
负责人：
Yuna Ayala
金额：
$ 37.88万
依托单位：
SAINT LOUIS UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-02-01 至 2025-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10553253
关键词：
ALS patients Acceleration Affect Age Alzheimer&apos s Disease Alzheimer&apos s disease patient Amyloid Amyloid beta-Protein Amyotrophic Lateral Sclerosis Antibodies Brain Cell model Cells Characteristics Collaborations Complex Core Assembly Cytoplasm DNA-Binding Proteins Disease Disease Marker Disease Progression Disease model Early Diagnosis Electrophoresis Epitopes Frontotemporal Dementia Future Goals Grant Human In Vitro Injections Lesion Link Mediating Methods Modeling Molecular Mus Mutagens Mutation Nerve Degeneration Neurodegenerative Disorders Parkinson Disease Pathogenesis Pathologic Pathology Patients Process Protein Isoforms Protein Region Proteins Proteolysis RNA RNA Recognition Motif RNA-Binding Proteins Reagent Role Source TDP-43 aggregation Testing Therapeutic Time Tissues Universities Variant Washington Work alpha synuclein combat detection method diagnostic biomarker diagnostic strategy frontotemporal lobar dementia amyotrophic lateral sclerosis gain of function hnRNP A1 in vivo in vivo Model insight link protein nervous system disorder neurotoxicity phosphoneuroprotein 14 prevent protein TDP-43 protein aggregation protein misfolding protein purification proteotoxicity recruit stress granule tau Proteins therapeutically effective tool tool development

项目摘要

The goal of this grant is to elucidate key mechanisms of TDP-43 aggregation by uncovering how this process leads to pathology and neurotoxicity. TDP-43 aggregation is the pathological hallmark of amyotrophic lateral sclerosis (ALS) and half of frontotemporal dementia (FTD) cases. In addition, TDP-43 lesions are a secondary pathology in approximately 50% of Alzheimer's disease. A major goal in combatting ALS and FTD has been to reduce the accumulation of TDP-43 inclusions by developing strategies to prevent or reverse TDP-43 aggregation. Recognizing this, we established strategic methods to study the aggregation of this RNA binding protein using purified TDP-43 and have identified previously unknown aggregate intermediates. These are early stage oligomers that share key characteristics with toxic oligomeric species of well-studied proteins linked to neurodegeneration, including Tau, amyloid-β and α-synuclein. These TDP-43 aggregate intermediates are capable of seeding de novo intracellular TDP-43 aggregation and their formation is accelerated by ALS-linked mutations. Our recent findings provide the unique opportunity to shed light on fundamental mechanisms of TDP-43 aggregation, determine their role in pathogenesis and provide models to block TDP-43 pathology. Aim 1 will establish the presence of TDP-43 oligomers in cellular models of aggregation and in ALS and FTD- derived tissue. In particular, we will examine recruitment of the intermediates to cytoplasmic stress granules, which are protein-RNA rich bodies considered to be crucibles of pathological aggregation. This will be achieved using our established methods of detection and by developing antibodies specific for the intermediate complexes. To establish the role of the newly found TDP-43 intermediates in aggregation and pathogenesis, Aim 2 will define the molecular determinants of assembly and test how disease-associated conditions upregulate this process. After identifying the protein regions mediating oligomerization, we will ask whether aggregation and intracellular seeding function decrease upon disruption of the newly identified epitopes. The ability of TDP-43 aggregates to act as agents of pathological spread in disease is strongly suggested by recent findings that FTD-derived extracts seed and propagate TDP-43 pathology in mouse brain. Aim 3 will test whether TDP-43 aggregates alone can indeed initiate de novo aggregation and propagation of pathology in vivo. We will analyze the spread of TDP-43 pathology upon injection of early and late stage TDP-43 aggregates derived from purified protein in the brain of mice. This will establish whether TDP-43 aggregates, and TDP-43 oligomers in particular, are primary sources of nucleation and neurotoxicity. Furthermore, these studies we will determine whether this propagation directly correlates with increased neurodegeneration. With the successful completion of this grant, we will: a) define fundamental processes in TDP-43 aggregation; b) establish in vitro and in vivo models to forestall neurotoxicity in ALS and FTD; and c) provide unprecedented tools for the development of diagnostic markers of disease.

这笔资助的目标是通过揭示 TDP-43 聚合过程如何进行来阐明该过程的关键机制导致病理学和神经毒性的 TDP-43 聚集是肌萎缩侧索硬化症的病理标志。硬化症 (ALS) 和一半额颞叶痴呆 (FTD) 病例此外，TDP-43 病变是继发性病变。大约 50% 的阿尔茨海默病的病理学是对抗 ALS 和 FTD 的一个主要目标。通过制定预防或逆转 TDP-43 的策略来减少 TDP-43 夹杂物的积累认识到这一点，我们建立了研究这种 RNA 结合聚集的策略方法。使用纯化的 TDP-43 蛋白质并鉴定出以前未知的聚集中间体。早期寡聚体与经过充分研究的蛋白质的有毒寡聚体具有共同的关键特征神经退行性疾病，包括 Tau、β 淀粉样蛋白和 α-突触核蛋白，这些 TDP-43 聚集中间体是能够从头播种细胞内 TDP-43 聚集，并且 ALS 连接加速其形成我们最近的发现为阐明突变的基本机制提供了独特的机会。 TDP-43 聚集，确定其在发病机制中的作用并提供阻断 TDP-43 病理学的模型。 1 将确定 TDP-43 寡聚物在细胞聚集模型以及 ALS 和 FTD 中的存在- 特别是，我们将检查细胞质应激颗粒的中间体的募集，这些富含蛋白质和RNA的体被认为是病理聚集的坩埚。使用我们既定的检测方法并开发针对中间体的特异性抗体来实现确定新发现的 TDP-43 中间体在聚集和发病机制中的作用，目标 2 将定义组装的分子决定因素并测试疾病相关状况如何在确定介导寡聚化的蛋白质区域后，我们会问是否上调该过程。新鉴定的表位被破坏后，聚集和细胞内播种功能就会降低。最近的研究强烈表明 TDP-43 聚集体作为疾病病理传播媒介的能力 Aim 3 将测试 FTD 提取的 TDP-43 病理学结果。 TDP-43 单独聚集是否确实可以引发从头聚集和病理学传播我们将分析注射早期和晚期 TDP-43 后 TDP-43 病理学的传播。来自小鼠大脑中纯化蛋白质的聚集体这将确定 TDP-43 是否聚集，尤其是 TDP-43 寡聚物，是成核和神经毒性的主要来源。我们将通过研究确定这种传播是否与神经变性的增加直接相关。为了成功完成这项资助，我们将： a) 定义 TDP-43 聚合的基本流程；建立体外和体内模型以预防 ALS 和 FTD 的神经毒性；以及 c) 提供前所未有的服务；开发疾病诊断标记物的工具。