The microRNAs (miRNAs) play an important role in regulating myogenesis by targeting mRNA. However, the understanding of miRNAs in skeletal muscle development and diseases is unclear. In this study, we firstly performed the transcriptome profiling in differentiating C2C12 myoblast cells. Totally, we identified 187 miRNAs and 4260 mRNAs significantly differentially expressed that were involved in myoblast differentiation. We carried out validation of microarray data based on 5 mRNAs and 5 miRNAs differentially expressed and got a consistent result. Then we constructed and validated the significantly up- and down-regulated mRNA-miRNA interaction networks. Four interaction pairs (miR-145a-5p-Fscn1, miR-200c-5p-Tmigd1, miR-27a-5p-Sln and miR-743a-5p-Mob1b) with targeted relationships in differentiated myoblast cells were demonstrated. They are all closely related to myoblast development. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated cell cycle signals important for exploring skeletal muscle development and disease. Functionally, we discovered that miR-743a targeting gene Mps One Binder Kinase Activator-Like 1B (Mob1b) gene in differentiated C2C12. The up-regulated miR-743a can promote the differentiation of C2C12 myoblast. While the down-regulated Mob1b plays a negative role in differentiation. In addition, the expression profile of miR-743a and Mob1b are consistent with skeletal muscle recovery after Cardiotoxin (CTX) injury. Our study revealed that miR-743a-5p regulates myoblast differentiation by targeting Mob1b involved in skeletal muscle development and regeneration. Our findings made a further exploration for mechanisms in myogenesis and might provide potential possible miRNA-based target therapies for skeletal muscle regeneration and disease in the near future.

microRNAs (miRNAs) 通过靶向 mRNA 在调节肌生成中发挥重要作用。然而，对骨骼肌发育和疾病中的 miRNA 的理解尚不清楚。在这项研究中，我们首先在 C2C12 成肌细胞的分化中进行了转录组分析。总共，我们确定了 187 个 miRNA 和 4260 个显着差异表达的与成肌细胞分化有关的 mRNA。我们基于5个mRNA和5个差异表达的miRNA对微阵列数据进行了验证，得到了一致的结果。然后我们构建并验证了显着上调和下调的 mRNA-miRNA 相互作用网络。四个相互作用对（miR-145a-5p- Fscn1、 miR-200c-5p- Tmigd1、 miR-27a-5p- Sln和 miR-743a-5p-Mob1b ) 在分化的成肌细胞中具有靶向关系。它们都与成肌细胞的发育密切相关。基因本体论 (GO) 和京都基因和基因组百科全书 (KEGG) 分析表明细胞周期信号对于探索骨骼肌发育和疾病很重要。在功能上，我们发现 miR-743a 在分化的 C2C12 中靶向基因 Mps One Binder Kinase Activator-Like 1B ( Mob1b ) 基因。上调的 miR-743a 可以促进 C2C12 成肌细胞的分化。而下调的Mob1b在分化中起负面作用。此外，miR-743a 和Mob1b的表达谱与心脏毒素（CTX）损伤后的骨骼肌恢复一致。我们的研究表明，miR-743a-5p 通过靶向参与骨骼肌发育和再生的 Mob1b 来调节成肌细胞分化。我们的研究结果进一步探索了肌生成的机制，并可能在不久的将来为骨骼肌再生和疾病提供潜在的基于 miRNA 的靶向治疗。