Deciphering the role of Ataxin-2 in amyotrophic lateral sclerosis

解读 Ataxin-2 在肌萎缩侧索硬化症中的作用

基本信息

批准号：
10231019
负责人：
Caitlin Marie Rodriguez
金额：
$ 6.86万
依托单位：
STANFORD 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：
2020-04-01 至 2022-09-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10231019
关键词：
Affect Affinity Chromatography Amyotrophic Lateral Sclerosis Axon Binding Biochemical Biotin CAG repeat Cell Line Cells Cerebral cortex Cessation of life Code Complex Cytoplasmic Granules DNA Defect Development Disease Drosophila genus Enzymes Functional disorder Future Gene Expression Process Genes Genetic Genetic Crosses Genetic Translation Genotype Goals Health Hemagglutinin Human Immunoprecipitation Individual Investigative Techniques Knock-out Knockout Mice Knowledge Length Link Longevity LoxP-flanked allele Maintenance Messenger RNA Modeling Motor Motor Neurons Mus Mutation Nerve Degeneration Neurodegenerative Disorders Neurons Pathology Pathway interactions Peripheral Permeability Peroxidases Phenols Poly(A)-Binding Proteins Population Post-Transcriptional Regulation Process Proteins Proteome RNA RNA Processing RNA metabolism RNA-Binding Proteins Radial Regulation Research RiboTag Ribosomal Proteins Ribosomes Role SCA2 protein Schools Skeletal Muscle Small Interfering RNA Spinal Cord Techniques Technology Testing Therapeutic Tissues Training Transcript Transgenes Transgenic Mice Transgenic Organisms Translating Translations Viral Vector Work Yeasts biological adaptation to stress career case-by-case basis embryonic stem cell experimental study genetic risk factor genome wide screen genome-wide human disease improved in vivo insight interest long term memory mRNA Decay messenger ribonucleoprotein motor neuron degeneration mouse model nanoluciferase nanometer nervous system disorder neuron loss neuronal cell body next generation sequencing novel novel therapeutic intervention polyglutamine protein TDP-43 sciatic nerve sporadic amyotrophic lateral sclerosis stress granule targeted treatment therapeutic development therapeutic target trafficking transcriptomics translation assay whole genome

项目摘要

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease characterized by progressive loss of voluntary muscle control [1]. The Gitler lab—where I will be conducting this research—discovered that a mutation in the ataxin-2 gene (ATXN2) is a relatively common genetic risk factor for ALS[2]. The mutation is an intermediate-length expansion of a CAG repeat in the ATXN2 coding region, leading to longer polyglutamine tracts in the Ataxin-2 protein. Reduction of the wild-type Atxn2 transcript extended survival and reduced pathology in a mouse model of ALS, as did crossing this mouse with the Ataxin-2 knockout mouse [3]. Despite these promising results, little is known about how wild-type Ataxin-2 contributes to ALS. Defects in RNA metabolism has emerged as a central mechanism in ALS[4-6]. Ataxin-2 is a regulator of mRNA translation, however transcripts under its control have only been identified on a case-by-case basis [7-12]. First, I am interested in exploring how knockout of Ataxin-2 elicits deficits in translation, and if this affords motor neurons protection in the transgenic TDP-43 (TDP-43tg/tg) ALS mouse model. I will use the expertise I gained during graduate school to perform genome-wide and biochemical translation assays but combine this with a new set of techniques for investigating mRNA dynamics in complex tissue. I will perform TRAP-seq, a technique for gauging the level of translation on individual transcripts by purifying mRNA bound to translating ribosomes [13]. This will allow me to determine transcripts with differential translation in TDP-43tg/tg mouse motor neurons, and how that is affected by the Ataxin-2 knockout. Ataxin-2 is an integral component of specialized messenger ribonucleoprotein (mRNP) granules and interacts with TDP-43 through RNA association [2, 8, 14]. mRNP granules are involved in the transport of mRNA to various parts of the cell for proper posttranscriptional processing [15, 16]. Deficits in axonal mRNA localization have been detected in both cultured peripheral neurons and mouse embryonic stem cell-derived motor neurons from multiple transgenic ALS mouse models, but never directly from tissue as the technology was not previously available [17, 18]. I will employ a novel technique called APEX-seq to determine the composition of mRNA transcripts spatially constricted to peripheral motor axons in WT and TDP-43tg/tg mice, and how this changes when crossed to the Ataxin-2 knockout[19, 20]. As described in my second aim, I will perform a genome-wide siRNA screen in human cells to discover regulators of Ataxin-2 that will illuminate pathways that work upstream to control its expression. The Gitler lab is proficient in large-scale approaches to identifying disease modifiers [21-23]. The goal of this aim is to harness our results to devise novel therapeutic strategies and to expand my training to include genome-wide screening. This project allows me the opportunity to expand my expertise in the topic of RNA metabolism in neurological disease, the topic I plan to make my career in researching, and to decipher the most promising targets for therapeutic development and future study.

肌萎缩营养性latal硬化症（ALS）是一种毁灭性的神经退行性疾病，其特征是程序性丧失自愿性肌肉[1] He Gitler Lab - 进行此研究 - 发现ataxin-2基因中的突变（ATXN2）是一种相对常见的遗传危险因素对于ALS [2]。 ATAXIN-2在RNA代谢中的缺陷已成为ALS N中的一种中心机制，该机制是逐案的基础[7-12] （TDP-43TG/TG）ALS小鼠模型。通过将mRNA与核糖体翻译为单个转录物上的翻译[13]。通过RNA结合与TDP-43相互作用[2，8，14]或适当的转录后处理[15，16]。从组织中，从组织中偶尔的转基因ALS慕斯从以前不可用[17，18]。在我的第二个目标中，我将在人类细胞中进行A范围的sirna屏幕，以发现gitler s表达的常规，这是识别大规模的方法，我将在我的第二个目标中描述。疾病改性剂[21-23]。疾病，我打算从事研究职业，并破译治疗发展和未来研究的最有希望的目标。