Molecular Pathphysiology of FSHD muscular dystrophy via genome-wide approaches

通过全基因组方法研究 FSHD 肌营养不良症的分子病理生理学

基本信息

批准号：
7209944
负责人：
YI-WEN CHEN
金额：
$ 35.69万
依托单位：
CHILDREN'S RESEARCH INSTITUTE
依托单位国家：
美国
项目类别：
财政年份：
2007
资助国家：
美国
起止时间：
2007-03-15 至 2012-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7209944
关键词：
4q35 Adult Affect Age Animal Model Anterior Apoptosis Appearance Belgium Binding Binding Sites Biochemical Biological Assay Biopsy Candidate Disease Gene Cells Chromosomes Clinical Computer software Consensus Creatine Kinase D4Z4 Data Dermatomyositis Development Disease Disease model Doxycycline Duchenne muscular dystrophy EMSA Embryonic Development Embryonic and Fetal Development Evaluation Face Facioscapulohumeral Facioscapulohumeral Muscular Dystrophy Fibroblasts Functional disorder Future Gene Expression Gene Expression Regulation Gene Targeting Genes Genetic Genetic Transcription Genome Goals Hindlimb Homeobox Homeostasis Homologous Gene In Vitro Inflammation Inherited Life Limb Development Limb structure Location Long-Term Effects Lower Extremity Luciferases Mediating Messenger RNA Modeling Molecular Molecular Profiling Molecular Target Monitor Mus Muscle Muscle Fibers Muscle Weakness Muscular Atrophy Muscular Dystrophies Mutagenesis Mutation Myoblasts Myopathy Natural regeneration Neuromuscular Diseases Onset of illness Oxidative Stress Pathogenesis Pathway interactions Patients Phenotype Phosphotransferases Play Predisposition Principal Investigator Process Promoter Regions Reporter Reporter Genes Research Research Personnel Reverse Transcriptase Polymerase Chain Reaction Role Series Serum Shoulder Siblings Site Skeletal Muscle Spinal Staging Testing Tetanus Helper Peptide Tetracycline Tetracyclines Time Tin Transcriptional Activation Transgenic Mice Transgenic Model Transgenic Organisms Triceps Brachii Muscle Ubiquitin Universities Up-Regulation Upper arm Week base chromatin immunoprecipitation day derepression disease phenotype expression vector fusion gene gene function gene induction gene interaction homeobox protein PITX1 homeodomain in vivo injured mouse genome mouse model multicatalytic endopeptidase complex postnatal programs promoter research study response sex transcription factor transgene expression vector wasting

项目摘要

DESCRIPTION (provided by applicant): Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant muscle disorder that is characterized by the progressive weakness and wasting of the muscles from face, upper-arm and shoulder girdle to lower limb. While there is consensus that FSHD is a disorder of transcription and gene regulation, the molecular pathways leading to muscular dystrophy and other unique clinical features of the disease are far from clear. Our preliminary study of whole genome profiles of 125 muscle biopsies representing 12 neuromuscular disorders showed that paired-like homeodomain transcription factor 1 (PITX1) gene was specifically up-regulated in FSHD patients. The significant PITX1 over-expression we observed in FSHD can not be due to inflammation, degeneration/ regeneration, or other "dystrophic" changes in muscle, as no other muscle disease (including juvenile dermatomyositis, Duchenne dystrophy, and others) showed up- regulation. Based on our extensive preliminary data both in vitro and in vivo, we present a model where over-expression of PITX1 in adult muscle invokes key muscle atrophy pathways, and, further, that PITX1 is regulated by DUX4 expression. The goal of this current proposal is to further develop our pathophysiological model to show direct relationships between 4q35 deletions, DUX4, and PITX1. The proposed research relies heavily on temporal series, conducted both in vivo and in vitro. Gene/gene interactions will also be determined. In aim 1, we propose to determine if Pitxl is a direct target of DUX4. We will determine whether a putative DUX4 binding site in the promoter region of Pitxl is functional, and whether it is specifically and directly regulated by DUX4. Additional DUX4 targets will be identified by temporal profiling. Interaction between DUX4 and potential target genes will be determined. In aim 2, we propose to generate and characterize a conditional muscle-specific Pitxl transgenic mouse model. The phenotype will be evaluated for changes in various clinical, functional, biochemical, molecular, and histological parameters. The phenotype of myoblasts, including appearance, proliferation, differentiation and susceptibility to oxidative stress, will also be evaluated. In addition, we will determine whether the disease phenotype is reversible. In aim 3, we will define molecular transcriptional pathways downstream of Pitxl expression using the Pitxl transgenic mouse. Temporal expression profiling will be performed to construct the pathways regulated by Pitxl. Interactions between Pitxl and potential regulatory targets of Pitxl will be further studied. Our preliminary data showed that disease-specific up-regulation of DUX4 and Pitxl and downstream changes of genes involved in muscle wasting might be involved in the pathophysiology of FSHD. The proposed research will identify key players in the pathological cascades of FSHD and define the interactions among them, which could potentially be used for developing treatments of the disease.

描述（由申请人提供）：Faciosculohumeral肌肉营养不良（FSHD）是一种常染色体显性肌肉障碍，其特征是逐渐无力和从脸部，上臂和肩膀束缚到下肢的肌肉。尽管有共识，即FSHD是一种转录和基因调节障碍，但导致肌肉营养不良的分子途径和该疾病的其他独特临床特征远非明显。我们对代表125种神经肌肉疾病的125个肌肉活检的整个基因组轮廓的初步研究表明，在FSHD患者中，对成对的类同源域转录因子1（PITX1）基因特别上调。我们在FSHD中观察到的明显的PITX1过表达不可能是由于炎症，变性/再生或其他肌肉中的其他“营养不良”变化，因为没有其他肌肉疾病（包括其他肌肉疾病（包括少年性皮肤肌炎，杜氏肌疾病症状疾病，其他营养不良症等））表现出了调节。基于我们在体外和体内的广泛初步数据，我们提出了一个模型，其中Pitx1在成人肌肉中的过表达会引起关键的肌肉萎缩途径，此外，PITX1受DUX4表达的调节。当前建议的目的是进一步发展我们的病理生理模型，以显示4q35缺失，DUX4和PITX1之间的直接关系。拟议的研究在很大程度上依赖于时间序列，在体内和体外进行了。基因/基因相互作用也将得到确定。在AIM 1中，我们建议确定PITXL是否是DUX4的直接目标。我们将确定PITXL启动子区域中的假定DUX4结合位点功能是否功能，以及它是否由DUX4进行了专门和直接调节。其他DUX4目标将通过时间分析确定。将确定DUX4与潜在靶基因之间的相互作用。在AIM 2中，我们建议生成和表征有条件的肌肉特异性PITXL转基因小鼠模型。将评估表型的各种临床，功能，生化，分子和组织学参数的变化。还将评估成肌细胞的表型，包括外观，增殖，分化和对氧化应激的敏感性。此外，我们将确定疾病表型是否可逆。在AIM 3中，我们将使用PITXL转基因小鼠在PITXL表达下游的分子转录途径。将进行时间表达分析以构建由PITXL调节的途径。将进一步研究PITXL与PITXL潜在调节目标之间的相互作用。我们的初步数据表明，DUX4和PITXL的疾病特异性上调以及涉及肌肉浪费的基因的下游变化可能与FSHD的病理生理有关。拟议的研究将在FSHD的病理级联中确定关键参与者，并定义它们之间的相互作用，这些相互作用有可能用于开发疾病的治疗方法。