Identifying the molecular mechanisms of GEMIN5 mutations in a novel cerebellar ataxia syndrome

鉴定新型小脑共济失调综合征中 GEMIN5 突变的分子机制

基本信息

批准号：
10753403
负责人：
Udai B Pandey
金额：
$ 53.97万
依托单位：
UNIVERSITY OF PITTSBURGH AT PITTSBURGH
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-09-15 至 2028-06-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10753403
关键词：
Affect Age of Onset Alternative Splicing Animals Applications Grants Ataxia Atrophic Behavior Biochemical Biogenesis Biological Biological Assay Biological Models Brain CRISPR/Cas technology Cells Cerebellar Ataxia Clinical Coenzyme Q10 Complex DNA Defect Developmental Delay Disorders Disease Drosophila genus Family Fibroblasts Foundations GEMIN5 gene Genetic Guide RNA Heterozygote Homologous Gene Human In Vitro Individual Induced pluripotent stem cell derived neurons Infant Intervention Lead Light Longevity Mitochondria Modeling Molecular Morphology Motor Motor Neuron Disease Motor Neurons Mus Mutation Neurologic Neurons Pathogenesis Pathogenicity Pathway interactions Patients Physiological Process Proteins Proteomics RNA Splicing RNA-Binding Proteins Reporting Respiration Rigor Mortis Role SMN protein (spinal muscular atrophy)SMN1 gene Small Nuclear Ribonucleoproteins Spinal Muscular Atrophy Spliceosomes Symptoms Syndrome Testing Time Transcript Transgenic Mice Transgenic Model Translations Variant autosome clinically relevant disease-causing mutation fly genetic variant human disease in vivo knock-down loss of function mRNA Precursor mitochondrial dysfunction motor disorder motor neuron degeneration mouse model mutant novel pharmacologic polysome profiling premature protein complex protein expression protein function protein protein interaction snRNP Structural Core Protein transcriptome sequencing translatome

项目摘要

Abstract GEMIN5, an RNA-binding protein, is essential for assembly of the Survival Motor Neuron (SMN) complex. GEMIN5 facilitates the formation of small nuclear ribonucleoproteins (snRNPs; the building blocks of spliceosomes). We identified novel autosomal recessive variants in the GEMIN5 gene in multiple patients presenting with motor dysfunction, ataxia, and cerebellar atrophy. Our proposed studies are aimed to understand the molecular mechanisms of mutant GEMIN5 responsible for causing the neurological abnormalities in our patients. We found that patient a significant decrease in GEMIN5 protein levels and reduced protein stability in patient iPSC neurons suggesting a possible loss of function mechanism. Our in vitro assembly assay showed that GEMIN5 variants perturb snRNP assembly formation. To understand the consequences of loss of function GEMIN5, we knockdown endogenous rigor mortis, the Drosophila homologue of human GEMIN5, in Drosophila. Knockdown of rigor mortis (rig) caused motor dysfunction, reduced life span and developmental delay. Interestingly, we observed that CoQ10 levels were significantly reduced in human patient cells and our drosophila model. Treatment with CoQ10 reduced the disease course in human GEMIN5 patients. We generated a mouse model of Gemin5 using CRISPR/cas9 and found early lethality in mice. Our proposed studies are aimed to understand the molecular mechanisms of GEMIN5 by 1) conducting functional analysis of mutant GEMIN5 patient neurons; 2) examining if GEMIN5 variants cause mitochondrial dysfunctions in vivo and iPSC neurons; and 3) investigating the mechanisms of GEMIN5 mutations in mouse models. We expect to identify the molecular pathways that are perturbed in human patients.

抽象的 Gemin5是一种RNA结合蛋白，对于存活运动神经元（SMN）的组装至关重要复杂的。 Gemin5促进了小核核糖核蛋白的形成（SNRNPS；剪接体的基础）。我们确定了新颖的常染色体隐性变体多个患有运动功能障碍，共济失调和小脑的患者的Gemin5基因萎缩。我们提出的研究旨在了解突变gemin5的分子机制负责导致我们患者的神经异常。我们发现患者A 双子座蛋白水平的显着降低和患者IPSC的蛋白质稳定性降低神经元表明可能丧失功能机制。我们的体外组装测定法表明gemin5变体扰动SNRNP组装形成。理解功能损失的后果，gemin5，我们敲除内源性严谨的莫蒂斯，果蝇中的人双子座的果蝇同源物。敲击严格的莫蒂斯（钻机）引起运动功能障碍，减少寿命和发育延迟。有趣的是，我们观察到人类患者细胞和我们的患者细胞中的COQ10水平显着降低果蝇模型。用COQ10治疗减少了人双子座的疾病病程患者。我们使用CRISPR/CAS9生成了Gemin5的鼠标模型，发现早期致死性在老鼠中。我们提出的研究旨在了解双子座的分子机制通过1）进行突变双子双子座患者神经元的功能分析； 2）检查是否 GEMIN5变体在体内和IPSC神经元中引起线粒体功能障碍； 3）研究小鼠模型中Gemin5突变的机制。我们希望确定人类患者受干扰的分子途径。