Understanding SHRF, an RNA exosome-linked disease with multi-organ involvement

了解 SHRF，一种与 RNA 外泌体相关的多器官受累疾病

基本信息

批准号：
10305689
负责人：
Bingwei Lu
金额：
$ 23.61万
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：
2020-12-01 至 2022-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10305689
关键词：
9q34 Address Affect Animal Model Atrophic Autophagocytosis Biological Models Biology Birth Brain imaging Cell Culture Techniques Cell Nucleus Cell model Cell physiology Cerebellar Cortex Chromosomes Complex Defect Dentate nucleus Disease Disease model Drosophila genus Engineering Enzymes Eukaryotic Cell Exhibits Face Facies Funding Opportunities Genes Genetic Genomics Hearing Human Inferior Institutes Intellectual functioning disability KH Domain Knowledge Label Lead Light Link Maintenance Malignant Neoplasms Mammalian Cell Mission Modeling Muscle Mutation Neonatal Neurodegenerative Disorders Neurons Olives - dietary Pathogenesis Patients Peroxidases Pontine structure Pontocerebellar hypoplasia Positioning Attribute Post-Transcriptional Regulation Process Proteins Pulmonary Fibrosis RNA RNA Binding RNA-Binding Proteins Regulation Research Retinitis Pigmentosa Rewards Ribonucleases Risk Role Signal Pathway Structure Testing Tissues Transcript United States National Institutes of Health Visual Visual impairment ascorbate base body system cell type disease phenotype exosome experience fetal fly hearing impairment in vivo induced pluripotent stem cell insight keratinocyte myelination nervous system development new technology novel scaffold

项目摘要

Project Summary Short stature, hearing loss, retinitis pigmentosa, and distinctive facies (SHRF) is a rare autosomal recessive disorder characterized by short stature, brachydactyly, dysmorphic facial features, hearing loss, and visual impairment. Patients also exhibit mild intellectual disability. SHRF is caused by homozygous or compound heterozygous mutation in the EXOSC2 gene, which encodes a subunit of the RNA exosome complex, a conserved multi-subunit ribonucleolytic complex that controls the 3´ to 5´ processing and degradation of various RNAs in all eukaryotic cells. Nine subunits (EXOSC1-9) form a catalytically inert core that serves as a scaffold for two ribonuclease subunits (EXOSC10 and Dis3). EXOSC2 and EXOSC3 are S1 and KH domain containing RNA-binding proteins that form the exosome cap structure. Intriguingly, despite the sequence similarity and similar positions in the exosome structure occupied by EXOSC2 and EXOSC3, mutations in these subunits result in distinct diseases, with mutations in EXOSC2 causing SHRF and mutations in EXOSC3 causing Pontocerebellar Hypoplasia type 1b (PCH1b), a rare autosomal recessive neonatal/fetal neurodegenerative disease characterized by hypoplasia and atrophy of the cerebellar cortex, dentate nuclei, pontine nuclei and inferior olives. That mutation in core subunits of a seemingly universally required RNA exosome complex can result in distinct diseases reflects inherent complexity in the organization, function, and regulation of this fundamental machinery of post-transcriptional gene regulation. But our understanding of the mechanistic basis underlying these processes is very limited. We hypothesize that RNA exosome subunits are assembled into different subcomplexes with different RNA substrate engagements, and that these subcomplexes may function in a tissue or cell type-specific manner. To test this hypothesis, we propose to employ the recently developed proximity labeling using the engineered enzyme ascorbate peroxidase 2 (APEX2) to systematically identify proteins and RNAs in the immediate proximity of EXOSC2 in mammalian cell culture models, including iPSC-derived neuronal and muscle models, and in vivo Drosophila models. The functional involvement of newly identified factors in exosome biology and SHRF pathogenesis will be tested in Drosophila models. Successful execution of this project will not only lead to new knowledge on the composition, regulation, and tissue-specific requirement of the RNA exosome complex, but also shed light on the pathogenesis of RNA exosome-linked diseases, from SHRF, PCH, SMA and pulmonary fibrosis to cancer, diseases affecting multiple body systems. It is therefore expected that findings from this study will be applicable to the missions of multiple NIH Institutes or Centers (ICs), one of the stated Research Objectives of this R21 funding opportunity.

项目摘要身材矮小，听力损失，色素性视网膜炎和独特的设施（SHRF）是罕见的常染色体隐性疾病的特征是身材矮小，腕足，营养不良的面部特征，听力丧失和视觉损害。患者还表现出轻度的智力障碍。 SHRF是由纯合或化合物引起的 exosc2基因中的杂合突变，该突变编码RNA外泌体复合物的亚基A 保守的多含量核糖核解水解复合物，控制3´至5´处理和降解所有真核细胞中的各种RNA。九个亚基（exosc1-9）形成了一种催化惰性核心，作为一个两个核糖核酸酶亚基的支架（Exosc10和dis3）。 exosc2和exosc3是S1和KH域包含形成外泌体帽结构的RNA结合蛋白。有趣的是，dospite序列 exosc2和exosc3占据的外泌体结构中的相似性和相似位置，突变中的突变这些亚基导致不同的疾病，exosc2中的突变导致SHRF和EXOSC3中的突变引起pontocerebellar发育不全1B（PCH1B），这是一种罕见的常染色体隐性新生儿/胎儿由小脑皮质下促炎和萎缩的神经退行性疾病，齿状核，蓬丁核和下橄榄。看似普遍需要的RNA的核心亚基中的突变外泌体复合物可以导致不同的疾病反映组织，功能和调节转录后基因调节的基本机制。但是我们对这些过程的机械基础非常有限。我们假设RNA外泌体亚基是与不同的RNA底物交战组装成不同的子复合物，这些子复合物可能以组织或细胞类型特异性方式起作用。为了检验这一假设，我们建议采用最近开发的使用工程酶抗坏血酸过氧化物酶2 （APEX2）系统地识别哺乳动物exosc2近距离的蛋白质和RNA 细胞培养模型，包括IPSC衍生的神经元和肌肉模型，以及体内果蝇模型。这新鉴定的外泌体生物学和SHRF发病机理中新确定的因素的功能参与将在果蝇模型。该项目的成功执行不仅会导致有关该项目的新知识 RNA外泌体复合物的组成，调节和组织特异性需求，但也浮出水面从SHRF，PCH，SMA和肺纤维化到癌症的RNA外泌体连接疾病的发病机理，影响多个身体系统的疾病。因此，预计这项研究的发现将是适用于多个NIH机构或中心（ICS）的任务，这是这个R21资金机会。