Identifying and understanding the role of repeat RNAs and RAN proteins in Alzheimer's disease

识别和理解重复 RNA 和 RAN 蛋白在阿尔茨海默病中的作用

• 批准号: 10263228
• 负责人: Lien Nguyen
• 金额: $ 7.67万
• 依托单位: UNIVERSITY OF FLORIDA
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-15 至 2023-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10263228
• 关键词: Activities of Daily Living; Affect; Age-Years; Alzheimer' s Disease; Alzheimer' s disease pathology; Alzheimer' s disease patient; Amyloid beta-Protein; Amyloid beta-Protein Precursor; Antibodies; Autophagocytosis; Autopsy; Biological Assay; Biology; Brain; Brain region; C-terminal; C9ORF72; CASP8 gene; Clinical; Cognitive; Complex; DNA Probes; Data; Dementia; Detection; Disease; Double-Stranded RNA; Early Onset Familial Alzheimer' s Disease; Frequencies; Frontotemporal Dementia; General Population; Genes; Genetic; Genomic DNA; Grant; Heterogeneity; High-Throughput Nucleotide Sequencing; Human; Human Genome; Impaired cognition; Induced pluripotent stem cell derived neurons; Inherited; Late Onset Alzheimer Disease; Link; Methods; Modeling; Molecular; Mus; Mutation; Neurodegenerative Disorders; Neurofibrillary Tangles; Neuromuscular Diseases; Pathogenicity; Pathologic; Pathology; Pathway interactions; Patients; Polymers; Proteins; RNA; Repetitive Sequence; Reporting; Risk Factors; Role; Sampling; Senile Plaques; Southern Blotting; Stress; Techniques; Testing; Text; Therapeutic; Tissues; Toxic effect; Toxicity Tests; United States; Variant; abeta accumulation; abeta deposition; abeta toxicity; base; behavioral impairment; disorder control; disorder risk; effective therapy; extracellular; follow-up; frontotemporal lobar dementia-amyotrophic lateral sclerosis; gain of function; hyperphosphorylated tau; individual patient; insight; multicatalytic endopeptidase complex; neuron loss; novel; novel therapeutics; presenilin-1; presenilin-2; protein aggregation; proteostasis; rapid technique; synaptic function; tau Proteins; tau phosphorylation; therapeutic development; therapeutic target

PROJECT SUMMARY/ABSTRACT (30 lines of text): Alzheimer’s disease, the most common form of dementia, is characterized by cognitive decline and impairment of behavioral and functional abilities. Approximate 5.8 million people in the United States are affected by Alzheimer’s disease (AD) and this number is anticipated to triple by 2050. While mutations in amyloid precursor protein (APP) and presenillin (PSEN1 and PSEN2) are known to cause familial early onset AD and the APOE4 variant is a well-known disease risk factor, the genetic contributions to the majority of late onset AD cases are not clear. Additionally, while the accumulation of Aβ plaques and hyperphosphorylated tau are considered to be hallmark features of AD cases, Aβ plaques and tau tangles do not fully explain the clinical features and heterogeneity found in AD patients. The identification of the C9orf72 GGGGCC hexanucleotide repeat expansion as the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia raises an intriguing question whether unidentified repeat expansion mutations contribute to other form of dementia including AD. Additionally, similarities in disease pathology are observed between AD and patients with repeat expansion disorders. These similarities include the accumulation of abnormal proteins, neuronal loss in affected brain regions, and the involvement of stress in worsening disease. While repetitive elements account for a large portion of the human genome, the detection repeat-expansion mutations, especially GC-rich repeat expansions, is challenging. To overcome the difficulties in identifying repeat expansion mutations, I have developed a novel dCas9-based repeat pull-down method (dCas9READ) that allows the isolation of repeat expansion mutations directly from the genomic DNA of individual patients. The objective of this proposal is to test the hypothesis that novel repeat expansion mutations contribute to late onset AD and their repeat containing RNA and RAN products are toxic and contribute to AD pathology. I am excited to report that in an initial screen, 17.5% of human AD autopsy cases tested were positive for RAN protein aggregates and RNA foci. In this grant, I will follow-up on these exciting preliminary data and test this hypothesis that novel repeat expansion mutations contribute to AD in the following specific aims: Aim 1) Will develop a novel dCas9-based technique for rapidly identifying repeat expansions. Aim 2) Will test the hypothesis that novel repeat expansions mutations are present at higher frequencies in late onset AD vs. control samples. Aim 3) Will test the hypothesis that novel repeat expansion mutations are toxic and contribute to AD pathology.

项目摘要/摘要(30行文本)： 阿尔茨海默病是痴呆症最常见的形式，其特征是认知能力下降和功能受损 行为能力和功能能力。美国约有580万人受到 阿尔茨海默病(AD)，这一数字预计到2050年将增加两倍。而淀粉样蛋白的突变 已知前体蛋白(APP)和早老素(PSEN1和PSEN2)可导致家族性早发性AD和 APOE4变异是一种众所周知的疾病风险因素，遗传因素导致了大多数晚发型 广告案例尚不清楚。此外，虽然Aβ斑块和过度磷酸化的tau的积累是 Aβ斑块和tau缠结被认为是AD患者的特征，但不能完全解释临床 阿尔茨海默病患者的特点和异质性。C9orf72 GGGGCC六核苷酸的鉴定 重复扩张是肌萎缩侧索硬化症和额颞部硬化症最常见的遗传原因 痴呆症提出了一个耐人寻味的问题，未知的重复扩增突变是否会导致其他 包括阿尔茨海默病在内的各种形式的痴呆。此外，AD和AD在疾病病理上也有相似之处。 反复扩张性疾病的患者。这些相似之处包括异常蛋白质的积累， 受影响的大脑区域的神经元丢失，以及压力参与了疾病的恶化。虽然是重复的 元素占人类基因组的很大一部分，检测重复扩展突变， 尤其是富含GC的重复扩增，是具有挑战性的。克服识别重复的困难 扩展突变，我开发了一种新的基于dCas9的重复下拉方法(DCas9READ)，它 允许直接从个体患者的基因组DNA中分离重复扩增突变。这个 这项建议的目的是检验新的重复扩增突变导致迟发的假设 发病的AD及其含有RNA和RAN产物的重复序列是有毒的，并有助于AD的病理。我是 兴奋地报告说，在最初的筛查中，17.5%的人类AD尸检病例RAN呈阳性 蛋白质聚集体和RNA焦点。在这笔赠款中，我将跟进这些令人兴奋的初步数据，并测试这一点 假设新的重复扩增突变在以下特定目的中有助于AD：目标1)将 开发一种基于dCas9的新技术，用于快速识别重复扩展。AIM 2)将测试 假设新的重复扩增突变在晚发性阿尔茨海默病患者中出现的频率更高。 对照样品。目标3)将检验这样一种假设，即新的重复扩增突变是有毒的，并有助于 到AD病理学。