Dystrophin-like dys-1 gene is expressed and required in muscle tissue, playing a vital role in gravisensing in Caenorhabditis elegans (C. elegans). To date, microRNA (miRNA)-mediated epigenetic mechanism in microgravity-induced muscular atrophy remains to be elucidated. In the present study, we first analyzed mRNA and miRNA expression profiles in space-flown dys-1(cx18) mutants and wild type worms (wt) of C. elegans. The results showed that spaceflight and microgravity have fewer effects on mRNA and miRNA expression in dys-1 mutant than in wt worms. mRNA and miRNA expression patterns of dys-1 mutants were changed by microgravity. Hierarchical clustering analysis showed that the alterations of genes function on neuromuscular system under space environment. Seven miRNAs (cel-miR-52, 56, 81, 82, 84, 124 and 230) have 18 significant anti-correlated target genes under space environment. RT-qPCR analysis confirmed that miR-52 and cdh-3, miR-84 and lin-14, miR-124 and mgl-3 in dys-1 mutants reversely altered under microgravity environment and in simulated microgravity experiment. Locomotion ability was only reduced in F0 wt worms but not in dys-1 mutants as well as their F1 offspring after simulated microgravity. We observed expression alterations of 7 neuromuscular genes (unc-27, nlp-22, flp-1, egl-5, flp-4, mgl-3, unc-94) in F0 wt worms, which might be involved in the regulation of locomotion ability of C. elegans. This study provides important insights to reveal the mechanism in the pathogenesis of muscular atrophy induced by microgravity.

肌营养不良蛋白样dys-1基因在肌肉组织中表达和需要，在秀丽隐杆线虫 (C. elegans)的重力感应中起着至关重要的作用。迄今为止，microRNA (miRNA) 介导的微重力引起的肌肉萎缩的表观遗传机制仍有待阐明。在本研究中，我们首先分析了太空飞行的dys-1(cx18)突变体和秀丽隐杆线虫的野生型蠕虫 (wt) 中的 mRNA 和 miRNA 表达谱。结果表明，与 wt 蠕虫相比，太空飞行和微重力对dys-1突变体中 mRNA 和 miRNA 表达的影响更小。dys-1的mRNA和miRNA表达模式突变体因微重力而改变。层次聚类分析表明基因的改变在空间环境下影响神经肌肉系统。七种miRNA（cel-miR-52、56、81、82、84、124和230）在太空环境下具有18个显着的反相关靶基因。RT-qPCR 分析证实，在微重力环境和模拟微重力实验中，dys-1突变体中的miR-52 和cdh-3、miR-84 和lin-14、miR-124 和mgl-3发生反向变化。运动能力仅在 F0 wt 蠕虫中降低，但在模拟微重力后的dys-1突变体及其 F1 后代中没有。我们观察到 7 个神经肌肉基因的表达改变（unc-27, nlp-22, flp-1, egl-5, flp-4, mgl-3, unc-94 ) 在 F0 wt 蠕虫中，这可能参与了线虫运动能力的调节。这项研究为揭示微重力引起的肌肉萎缩的发病机制提供了重要的见解。