An alternative isoform of RRM2B as a genetic modifier in Huntington's disease

RRM2B 的另一种亚型作为亨廷顿病的遗传修饰剂

基本信息

批准号：
10405581
负责人：
Ihn Sik Seong
金额：
$ 39.48万
依托单位：
MASSACHUSETTS GENERAL HOSPITAL
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：
2020-07-01 至 2025-04-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10405581
关键词：
Affect Age of Onset Alleles Amino Acids Antisense RNA Binding Biochemical Biological Biological Assay Biological Models Biology CAG repeat CRISPR/Cas technology Cell Differentiation process Cell Survival Cell model Cells Cellular Stress Characteristics Chemicals Chromosome 8 Clustered Regularly Interspaced Short Palindromic Repeats Complex DNA Maintenance Data Diphosphates Disease Drug Design Engineering Exons Foundations Future Gene Expression Gene Transfer Genes Genetic Genetic study Goals Haplotypes Homeostasis Human Huntington Disease Huntington gene Inherited Investigation Knock-out Knockout Mice Label Length Light Maintenance Mediating Methods Mitochondria Mitochondrial DNA Mitochondrial DNA depletion syndromes Modification Molecular Mutation Neurodegenerative Disorders Neurons Onset of illness Outcome Oxidoreductase Pathogenesis Pathogenicity Pathologic Pathway interactions Patients Persons Phenotype Play Ploidies Primates Protein Isoforms Proteins Proteomics RRM1 gene Regulation Resources Rest Ribonucleosides Ribonucleotide Reductase Role Sample Size Series Signal Transduction Source Stress TP53 gene Techniques Testing Therapeutic Therapeutic Effect Therapeutic Intervention Time Trinucleotide Repeat Expansion Untranslated RNA Variant Work base biological adaptation to stress design disease phenotype exon skipping expectation experimental study follow-up gene therapy genetic analysis genome wide association study induced pluripotent stem cell innovation insight knock-down mitochondrial dysfunction motor symptom nerve stem cell nervous system disorder neuron loss new technology novel novel therapeutics polyglutamine premature prevent protein complex recognins response small hairpin RNA spatiotemporal stressor therapeutic candidate therapeutic development tool transcriptome ubiquitin-protein ligase

项目摘要

The pathogenic mechanism of Huntington’s disease (HD), a fatal, dominantly inherited neurodegenerative disorder caused by trinucleotide repeat expansion in the huntingtin (HTT) gene, is poorly understood, stymieing therapeutic development. Our overarching goal is to better understand HD pathogenesis and identify targetable pathways for therapeutic intervention by studying genetic modifiers of HD, initially identified by the GeM-HD consortium. The objective of this proposal is to evaluate one HD modifier, ribonucleoside-diphosphate reductase subunit M2 B (RRM2B), by delineating its isoform-specific biological activity on mitochondrial regulation and characterizing its effect on HD pathogenesis. Our hypothesis is that the two SNPs in chr8 GWAS modifier haplotype, rs1037699 and rs5893603, shown to lower RRM2B isoform 2 levels, play a critical role in isoform 2- specific complex(es), altering overall RRM2B activity and HD pathogenesis. Upon completion, this work will validate RRM2B isoform 2 as a modulator of HD pathogenesis and serve as a foundation for novel therapeutic disease-altering strategies as well as providing insight into the fundamental mechanism of HD by: 1) Characterizing isoform-specific RRM2B activity, focusing on its role in mitochondrial regulation, on subcellular localization, stress-response assays, and knockdown experiments in LCLs and human neuronal progenitor cells (hNPCs) and neurons differentiated from our new HTT isogenic series of iPSCs with different CAG sizes (17, 40, 51 and 61); 2) Identifying key cellular protein complexes containing RRM2B isoform 2 in a stress and time dependent manner using APEX-mediated quantitative proteomics; 3) Evaluating potential therapeutic effects by augmenting RRM2B isoform 2 levels in HD patient cells using novel technologies, such as non-coding antisense RNA (SIENUP). Novel techniques and resources include sensitive allele-specific SRM-MS for targeted quantification, recently optimized gene therapy tools, and innovative HD cell model systems, designed to precisely delineate CAG signatures relevant for HD. This proposal will unveil the interface between RRM2B biology and HD pathogenesis, establishing RRM2B as a targetable pathway and potentially revealing other players in the pathogenic cascade. Our expectation is that strategies to upregulate RRM2B isoform 2 level will have a positive effect on HD phenotypes, providing a key candidate for therapeutics. Overall, the positive outcomes of this work will enable us to better understand the effect of genetic modifiers on HD and validate immediate targets for rational drug design, providing additional avenues for future therapeutic strategies.

亨廷顿氏病（HD）的致病机制，这是一种致命的，主要遗传的神经退行性的亨廷顿蛋白（HTT）基因中三核苷酸重复扩张引起的障碍，对治疗发展。我们的总体目标是更好地了解高清发病机理并确定可定位的通过研究HD的遗传修饰剂的热干预途径，最初由GEM-HD鉴定财团。该提案的目的是评估一个HD修饰符，丝双磷酸二磷酸盐还原剂亚基M2 B（RRM2B），通过描述其在线粒体调节和表征其对HD发病机理的影响。我们的假设是CHR8 GWAS修饰符中的两个SNP 单倍型，RS1037699和RS5893603，显示为降低RRM2B同工型2级，在同工型2--中起关键作用特定的复合物（ES）改变了总体RRM2B活性和HD发病机理。完成后，这项工作将验证RRM2B同工型2作为HD发病机理的调节剂，并作为新治疗的基础改变疾病的策略，并提供有关HD基本机制的见解：1）表征同工型特异性RRM2B活性，重点是其在线粒体调节中的作用 LCL和人类神经祖细胞中的定位，应力反应测定和敲低实验（HNPC）和神经元与我们的新型HTT等源性IPSC区分开，具有不同的CAG尺寸（17、40，， 51和61）; 2）在应力和时间下识别含有RRM2B同工型2的钥匙细胞蛋白复合物使用APEX介导的定量蛋白质组学的依赖方式； 3）评估潜在的治疗作用使用新技术，例如非编码反义 RNA（Sienup）。新颖的技术和资源包括针对目标的敏感等位基因特异性SRM-MS 定量，最近优化的基因疗法工具和创新的HD细胞模型系统，旨在精确地描绘了与高清相关的CAG签名。该建议将揭示RRM2B之间的接口生物学和HD发病机理，将RRM2B建立为可靶向途径，并有可能揭示其他病原级联的玩家。我们的期望是，将RRM2B同工2级上调的策略将对HD表型有积极影响，为治疗提供了关键的候选者。总体而言，积极这项工作的结果将使我们能够更好地了解遗传修饰符对HD的影响并验证合理药物设计的直接目标，为未来的治疗策略提供了其他途径。