RNA Processing-Mediated Mechanisms of CNS Dysfunction in Myotonic Dystrophy

强直性肌营养不良中 CNS 功能障碍的 RNA 加工介导机制

• 批准号: 10651422
• 负责人: GARY J BASSELL
• 金额: $ 7.29万
• 依托单位: UNIVERSITY OF FLORIDA
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10651422
• 关键词: 3' Untranslated Regions; Adult; Affect; Alternative Splicing; Animal Model; Antisense Oligonucleotides; Autopsy; Behavioral; Biological Markers; Biology; Brain; Brain imaging; CUG repeat; Cerebrospinal Fluid; Childhood; Clinical Trials; Cognitive; Complex Mixtures; Defect; Diagnosis; Disease; Disease Marker; Disease Progression; Dissection; Dominant Genetic Conditions; Dopamine D2 Receptor; Down Syndrome; Drowsiness; Equilibrium; Event; Excitatory Synapse; Exhibits; Exons; FDA approved; Fatigue; Fragile X Syndrome; Functional disorder; Future; Gene Expression Profiling; Genetic Diseases; Glutamates; Goals; Heart; Human; Huntington Disease; Image; Impairment; Inherited; Inhibitory Synapse; Knockout Mice; Lead; Link; Measures; Mediating; Methods; Modality; Modeling; Molecular; Mus; Muscle; Muscle Weakness; Muscle function; Myotonia; Myotonic Dystrophy; NMDA receptor A1; Neuraxis; Neurons; Neurotransmitters; Patients; Persons; Pharmaceutical Preparations; Phenotype; Physiological; Play; Polyadenylation; Post-Transcriptional Regulation; Prevalence; Protein Isoforms; Protein Kinase; Proteins; Public Health; RNA; RNA Processing; RNA Splicing; RNA-Binding Proteins; Raclopride; Research; Role; Skeletal Muscle; Sleep disturbances; Spliced Genes; Symptoms; Synapses; Therapeutic; Tissues; Transcript; Transgenic Mice; Vertebrates; Work; autism spectrum disorder; base; behavioral phenotyping; biomarker development; biomarker-driven; brain dysfunction; brain tissue; cell type; clinical phenotype; efficacy evaluation; experience; gamma-Aminobutyric Acid; gene therapy; genome-wide; human data; improved; insight; molecular phenotype; mouse model; nervous system disorder; neurophysiology; novel therapeutic intervention; receptor; restoration; synaptic function; targeted agent; targeted treatment; transcriptome; transcriptome sequencing; wasting

Myotonic dystrophy (dystrophia myotonica, DM) is an autosomal dominant genetic disease, with a diagnosed prevalence of 1:8000 people worldwide, that affects multiple tissues of the body, including skeletal muscle, heart, and related to this proposal, the central nervous system (CNS). DM1 is caused by expanded CTG repeats in the 3' UTR of dystrophia myotonica protein kinase (DMPK). There is substantial evidence in mouse DM1 models and human DM1 postmortem tissue to support an RNA-mediated disease mechanism where toxic intranuclear CUG RNA foci sequester Muscleblind (MBNL) RNA binding proteins that normally play crucial roles to regulate various aspects of post-transcriptional gene regulation. A major gap in our understanding is that we do not know which RNA processing defects underlie specific impairments in DM1 brain function. Recent work together with our new findings suggests that missplicing of RNAs encoding synaptic proteins is responsible for CNS dysfunction in DM1. Our central hypothesis is that CNS phenotypes are directly attributed to loss of MBNL mediated RNA processing and that restoration of MBNL activity and/or splicing can restore brain function. Our goal is to gain a thorough understanding of RNA processing-mediated mechanisms of CNS dysfunction in DM1 and use this to develop and rigorously evaluate novel therapeutic strategies. The overall objectives of this proposal are to use both candidate and genome wide approaches, applied to MBNL KO mice and a new AAV9 based neuronal mouse model, compared to RNAseq analysis of human postmortem brain, to evaluate the role of specific splicing events to drive symptoms, and to comprehensively identify changes in missplicing and RNA processing. Aim 1 will characterize how dysregulation of GABRG2, GRIN1, and SNAP25 splicing events is linked to molecular, cellular, and behavioral phenotypes observed in DM1. Aim 2 will develop a new AAV9 based mouse model to elucidate the set of RNA processing events in neurons that cause DM1 phenotypes, through transcriptional profiling and overlap of human DM brains with DM mouse model brains. Aim 3 will assess the extent to which antisense oligonucleotides or MBNL expression can rescue molecular, cellular, physiologic and behavioral phenotypes in DM1 mouse models. These studies will provide new mechanistic insights into how perturbations to specific RNA processing events can lead to CNS symptoms in myotonic dystrophy, and provide a broader comprehensive view of all transcriptome changes occurring in the DM CNS. The proposed work is significant, as no molecular changes have been linked to any phenotypes in the DM CNS. This provides the framework for future therapeutic efforts aimed at correcting CNS defects.

强直性肌营养不良（dystrophicamyotonica，DM）是一种常染色体显性遗传病， 全球患病率为1：8000，影响身体的多个组织，包括骨骼肌， 心脏，以及与此建议相关的中枢神经系统（CNS）。DM 1由CTG扩张引起 在强直性肌营养不良症蛋白激酶（DMPK）的3' UTR中的重复序列。有大量证据表明， DM 1模型和人DM 1死后组织来支持RNA介导的疾病机制，其中 毒性核内CUG RNA灶隔离肌盲（MBNL）RNA结合蛋白， 在调节转录后基因调控的各个方面发挥重要作用。我们的一个主要差距是 我们的理解是，我们不知道哪些RNA加工缺陷是DM 1中特定损伤的基础 大脑功能最近的工作与我们的新发现一起表明，RNA编码的错误剪接 突触蛋白负责DM 1中的CNS功能障碍。我们的中心假设是中枢神经系统的表型 直接归因于MBNL介导的RNA加工的丧失和MBNL活性的恢复和/或 拼接可以恢复大脑功能我们的目标是彻底了解RNA加工介导的 DM 1中CNS功能障碍的机制，并利用这一点来开发和严格评估新的治疗方法， 战略布局该提案的总体目标是使用候选方法和全基因组方法， 应用于MBNL KO小鼠和新的基于AAV 9的神经元小鼠模型，与使用RNAseq分析比较， 人类死后大脑，以评估特定剪接事件驱动症状的作用，并 全面识别错误剪接和RNA加工的变化。目标1将描述如何 GABRG 2、GRIN 1和SNAP 25剪接事件的失调与分子、细胞和行为有关 在DM 1中观察到的表型。目的2将建立一种新的基于AAV 9的小鼠模型，以阐明RNA组 在神经元中处理导致DM 1表型的事件，通过转录谱分析和重叠， 人DM脑与DM小鼠模型脑。目标3将评估反义核酸在多大程度上 寡核苷酸或MBNL表达可以挽救细胞中的分子、细胞、生理和行为表型。 DM 1小鼠模型。这些研究将提供新的机制的见解如何扰动到特定的 RNA加工事件可导致强直性肌营养不良的CNS症状，并提供更广泛的 DM CNS中发生的所有转录组变化的全面视图。拟议的工作意义重大， 因为没有分子变化与DM CNS中的任何表型相关。这提供了框架， 旨在纠正CNS缺陷的未来治疗努力。