Effects of MicroRNA-27a on Myogenin Expression and Akt/FoxO1 Signal Pathway during Porcine Myoblast Differentiation.

Skeletal myoblast differentiation is controlled by a multitude of transcription factors and signal pathways. Myogenin is a critical transcriptional regulator in the initiation and maintenance of myoblast differentiation. The Akt/FoxO1 signal pathway plays an important role in myoblast differentiation. MicroRNAs are a kind of small noncoding RNAs that have been regarded as important regulators in skeletal muscle cell proliferation and differentiation. The objective of this study was to investigate the effects of microRNA-27a (miR-27a) on myogenin expression and Akt/FoxO1 signal pathway during porcine myoblast differentiation. Here, we found that the expression of miR-27a was gradually diminished at the early differentiation stage and then rebounded. Overexpression of miR-27a suppressed the mRNA and protein expression levels of myogenin during porcine myoblast differentiation, whereas inhibition of miR-27a promoted the mRNA and protein expression levels of myogenin. In addition, overexpression of miR-27a decreased the level of P-Akt/Akt and increased the protein level of FoxO1; however, inhibition of miR-27a increased the level of P-Akt/Akt and decreased the protein level of FoxO1. The present study demonstrated that miR-27a could inhibit myogenin expression and Akt/FoxO1 signal pathway during porcine myoblast differentiation.