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.