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

基本信息

批准号：
10055279
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
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-09-15 至 2022-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10055279
关键词：
Activities of Daily Living Affect Age-Years Alzheimer&apos s Disease Alzheimer&apos s disease pathology Alzheimer&apos 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&apos s Disease Frequencies Frontotemporal Dementia General Population Genes Genetic Genomic DNA Grant Heterogeneity High-Throughput Nucleotide Sequencing Human Human Genome Impaired cognition Inherited Late Onset Alzheimer Disease Link Methods Modeling Molecular Mus Mutation Neurodegenerative Disorders Neurofibrillary Tangles Neuromuscular Diseases Neurons 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 induced pluripotent stem cell 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

项目摘要

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）：阿尔茨海默病是最常见的痴呆症，其特点是身体衰退和损伤美国大约有 580 万人受到影响。阿尔茨海默病 (AD) 的数量预计到 2050 年将增加两倍。而淀粉样蛋白突变已知前体蛋白 (APP) 和早老素（PSEN1 和 PSEN2）会导致家族性早发性 AD 和 APOE4 变异是众所周知的疾病危险因素，遗传因素对大多数迟发型发病有贡献此外，AD 病例尚不清楚，但 Aβ 斑块和过度磷酸化 tau 蛋白的积累尚不清楚。 Aβ 斑块和 tau 蛋白缠结被认为是 AD 病例的标志性特征，但并不能完全解释临床症状 AD 患者中发现的特征和异质性 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叶硬化症最常见的遗传原因痴呆症提出了一个有趣的问题：未识别的重复扩增突变是否会导致其他疾病此外，AD 和 AD 之间在疾病病理学上也有相似之处。这些相似之处包括异常蛋白质的积累，受影响大脑区域的神经元损失，以及压力导致疾病恶化。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的重复扩展，要克服识别重复的困难是具有挑战性的。扩展突变，我开发了一种新颖的基于 dCas9 的重复下拉方法（dCas9READ）允许直接从个体患者的基因组 DNA 中分离重复扩增突变。该提案的目的是检验新的重复扩展突变导致晚期的假设发病的 AD 及其重复含有 RNA 和 RAN 产物是有毒的，会导致 AD 病理。很高兴地报告，在初步筛查中，17.5% 的人类 AD 尸检病例 RAN 检测呈阳性在这笔资助中，我将跟踪这些令人兴奋的初步数据并对其进行测试。假设新的重复扩展突变在以下特定目标中有助于 AD：目标 1) 将开发一种基于 dCas9 的新型技术，用于快速识别重复扩展。目标 2) 将测试假设新的重复扩展突变在晚发性 AD 中出现的频率比在晚发性 AD 中出现的频率更高。目标 3) 将检验新的重复扩增突变是有毒的并有助于这一假设。 AD 病理学。