Investigating proteostasis in facioscapulohumeral muscular dystrophy

研究面肩肱型肌营养不良症的蛋白质稳态

• 批准号: 10430945
• 负责人: YI-WEN CHEN
• 金额: $ 18.03万
• 依托单位: CHILDREN'S RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-01 至 2024-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10430945
• 关键词: 4q35; Affect; Aftercare; Algorithms; Antisense Oligonucleotide Therapy; Antisense Oligonucleotides; Cells; Chromosomes; Complex; D4Z4; Data; Defect; Deuterium Oxide; Disease; Disease Progression; Double Effect; Enzyme-Linked Immunosorbent Assay; Epigenetic Process; Facioscapulohumeral Muscular Dystrophy; Gene Expression; Genes; Genetic; Genetic Transcription; Goals; Homeobox; Homeodomain Proteins; Hour; Human; In Vitro; Individual; Inherited; Isotope Labeling; Label; Liquid Chromatography; Metabolic; Molecular; Mus; Muscle; Muscle Cells; Muscular Dystrophies; Mutation; Myoblasts; Myopathy; Pathology; Patients; Peptides; Performance; Post-Transcriptional Regulation; Process; Protein Biosynthesis; Proteins; Regulation; Reporting; Repression; Research; Role; Siblings; Testing; Time; Transcription Process; Treatment Efficacy; Western Blotting; Work; Xenograft procedure; disease phenotype; efficacy evaluation; improved; in vivo; insight; knock-down; mouse model; muscular dystrophy mouse model; nanoscale; protein degradation; protein profiling; proteostasis; response; tandem mass spectrometry; therapeutic development; therapeutic target; treatment effect

ABSTRACT Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant muscle disorder caused by complex genetic and epigenetic mechanisms. Previous studies showed that transcription de- repression of double homeobox protein 4 (DUX4) due to epigenetic changes in the D4Z4 region causes FSHD. The epigenetic changes are caused by either contraction of the D4Z4 array from 11-150 repeat units in unaffected individuals to 1-10 repeat units in roughly 95% of patients (FSHD1), or mutations in epigenetic regulators of the D4Z4 region (FSHD2). The expression of DUX4 leads to downstream molecular and cellular changes, which contribute to disease progression. Previous studies reported defects in protein degradation process in FSHD, however what proteins are affected and whether protein synthesis is affected is not clear. To study the dynamic changes in protein abundance in affected muscle cells, the research team conducted a preliminary study using liquid chromatography - tandem mass spectrometry in combination with metabolic labelling. The study identified distinct protein profiles between the myoblasts from individuals affected by FSHD and their unaffected siblings. We hypothesize that DUX4 expression is responsible for the disturbance of protein homeostasis, which contributes to the downstream molecular and cellular defects observed in FSHD. In the proposed study, we will first study the protein synthesis and degradation in immortalized FSHD myoblasts before and after a DUX4-reducing treatment. In aim 2, we will validate the in vitro findings using a xenograft mouse model. This project will discover proteins that are mis-regulated by degradative processes and synthetic processes in FSHD, which may open new opportunities for therapeutic development. The findings will also provide new insights of the disease mechanisms and evaluate the efficacy of a DUX4-reducing treatment using antisense oligonucleotides targeting the DUX4.

抽象的 Facioscapulohumeral肌肉营养不良（FSHD）是常染色体显性肌肉疾病 由复杂的遗传和表观遗传机制引起。先前的研究表明，转录消除了 由于D4Z4区域的表观遗传变化而导致双重同源蛋白4（DUX4）的抑制 FSHD。表观遗传变化是由D4Z4阵列的任何收缩从11-150重复的收缩引起的 大约95％的患者（FSHD1）中未受影响的个体的单位至1-10个重复单位，或 D4Z4区域的表观遗传调节剂（FSHD2）。 DUX4的表达导致下游 分子和细胞变化，这有助于疾病进展。先前的研究报道 FSHD中蛋白质降解过程的缺陷，但是哪些蛋白质受到影响以及是否影响 蛋白质合成受到影响。研究蛋白质丰度的动态变化 影响肌肉细胞，研究小组使用液相色谱进行了初步研究 - 串联质谱与代谢标记结合。该研究确定了不同的蛋白质 来自FSHD影响的个体的成肌细胞与未受影响的兄弟姐妹之间的概况。我们 假设Dux4表达是造成蛋白质稳态的扰动的原因， 有助于在FSHD中观察到的下游分子和细胞缺陷。在拟议的研究中 我们将首先研究不朽的FSHD成肌细胞中的蛋白质合成和降解 经过DUX4还原处理后。在AIM 2中，我们将使用异种移植小鼠验证体外发现 模型。该项目将发现因降解过程和合成而误导的蛋白质 FSHD中的过程，这可能为治疗开发打开新的机会。调查结果会 还提供有关疾病机制的新见解，并评估DUX4降低的功效 使用针对DUX4的反义寡核苷酸的处理。