Regulation of IL7R splicing by DDX39B and its role in Multiple Sclerosis

DDX39B 对 IL7R 剪接的调节及其在多发性硬化症中的作用

基本信息

批准号：
8974742
负责人：
Gaddiel Galarza Munoz
金额：
$ 5.7万
依托单位：
UNIVERSITY OF TEXAS MED BR GALVESTON
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-06-01 至 2017-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8974742
关键词：
Alleles Alternative Splicing Animal Model Autoimmune Diseases Autoimmunity Binding Biochemical Genetics Bioinformatics Boxing Cells Chronic Code Collaborations Complex Demyelinations Development Disease Disease Outcome Elements Etiology Exons Family Family member Gene Expression Gene Expression Profiling Genes Genetic Genotype Goals Health Human IL7R gene Immunoprecipitation In Vitro Individual Interleukin 7 Receptor Interleukin-7 Length Life Link Messenger RNA Molecular Multiple Sclerosis Neuraxis Neurologic Dysfunctions Nonsense-Mediated Decay Pathogenesis Patients Play Polypyrimidine Tract-Binding Protein Positioning Attribute Predisposition Production Protein Isoforms Proteins RNA RNA Helicase RNA Processing RNA Splicing Regulation Regulator Genes Reporter Repression Research Risk Risk Factors Role Signal Pathway Single Nucleotide Polymorphism Spliceosomes Susceptibility Gene Testing Therapeutic Therapeutic Intervention Tissue-Specific Gene Expression Trans-Activators Transcription Initiation Site Work base crosslink curative treatments disabling disease effective therapy exon skipping genetic approach in vivo neuron loss novel protein complex receptor research study

项目摘要

DESCRIPTION (provided by applicant): Multiple Sclerosis (MS) is an autoimmune disorder of the central nervous system typified by axonal demyelination and neuronal death. To date, there is no effective treatment to cure the disease, and the available therapies do not alter the outcome of the disease. The development of better therapeutic options requires in-depth understanding of the molecular mechanisms leading to disease development and progression. Our group previously discovered a single nucleotide polymorphism (SNP, rs6897932) within exon 6 of the IL-7 receptor alpha chain (IL7R) that is strongly associated with the risk of developing MS. Our group further showed that the MS-associated allele of the SNP increases skipping of exon 6 both in vitro and in vivo, leading to increased production of a secreted receptor (sIL7R) that is unable to activate the IL-7 signaling pathway. Importantly, sIL7R has been linked to the disease in both human patients and animal models. These results directly implicate splicing of IL7R to the pathogenesis of MS, and posit the trans-acting factors controlling its splicing as candidate MS susceptibility genes. I have uncovered two of the trans-factors controlling IL7R exon 6 splicing: the RNA helicase DDX39B, which activates exon inclusion, and the polypyrimidine tract binding protein (PTBP1), which represses it. Furthermore, we uncovered several SNPs in the DDX39B gene region that are associated with MS, thereby establishing DDX39B is itself a risk factor for MS. None of the associated SNPs are located within the coding sequence of the gene, suggesting that one or more of these SNPs may contribute to the disease association by modifying DDX39B expression. Through bioinformatics and gene expression analyses, I have uncovered mRNA isoforms encoding either the full-length protein or a novel short protein, and several mRNA isoforms that are candidate targets for nonsense-mediated decay. Importantly, I have established two of the SNPs could alter expression levels of these isoforms. The goal of this proposal is to provide functional links connecting DDX39B to the pathogenesis of MS. Specifically, I aim to: 1) elucidate its role in the regulation of IL7R exon 6 splicing; 2) understand the functional roles of the different protein isoforms; and 3) uncover the SNPs responsible for its association with MS. I will combine biochemical and genetic approaches to elucidate the mechanism by which DDX39B activates exon 6 splicing, and to characterize the functional roles of the protein isoforms. I will test the impact of selected SNPs on DDX39B expression by combining in vivo gene expression analysis and functional studies using reporter minigenes. Successful completion of this research will advance our current understanding of the molecular underpinnings of MS, in particular by functionally linking DDX39B to the pathogenesis of MS, and providing a functional characterization of the DDX39B gene. Given that DDX39B has been associated with numerous autoimmune disorders, our results could be relevant to the mechanistic etiology of other autoimmune diseases.

描述（由申请人证明）：多发性硬化症（MS）是中枢神经系统的自身免疫性疾病，迄今为止，没有有效治疗该疾病的治疗方法，并且可用的疗法不会改变其结果疾病。更好的治疗选择需要深入了解疾病发展和进展的分子机制。（IL7R）与在体外和体内均进一步发展我们的小组的风险密切相关，从而增加了分泌受体的产生SE的结果直接暗示了IL7R的剪接与控制其候选者MS的发病机理，该MS SUSCOVERCOVER COVERIAD ORCONTISE IL7R外显子6剪接：RNA DDX39B，激活外显酰胺含量，以及polypyrimide Tract Tract Tract Tract Tract结合蛋白（PTBP1）（PTBP1）它。我们在与MS OCIDED SNP相关的DDX39B基因中发现了SNP，这表明这些SNP可以通过修改DDX39B Express来促进这些SNP的效果。，我已经建立了X39b的两个SNP，以表达X39B的发病机理，我的目标是：1）阐明是在调节IL7R外显子6剪接中的作用； 3）与MS相结合的SNP结合了DDX39B激活外显子6的生化和遗传方法，以使用Reporter Minigenez的MS，MIS，蛋白质分析和功能研究。特别是通过将DDX39B连接到MS的发病机理，并提供了DDX39B基因的功能表征。