MicroRNA-145 Inhibitor Significantly Improves the Development of Bovine Somatic Cell Nuclear Transfer Embryos In Vitro.

Directly regulating the translation of POU5F1, SOX2, KLF4, and miRNA-145 plays an important role in maintaining the pluripotency of stem cells and the development of early embryos. In the present study, the expression model of miRNA-145 on bovine somatic cell nuclear transfer (SCNT) and in vitro fertilized (IVF) embryos were investigated and compared. Results indicated that (1) the expression level of miRNA-145 was significantly higher in SCNT embryos than that in IVF embryos after the eight-cell stage; (2) miRNA-145 negatively regulated the POU5F1, SOX2, and KLF4 in bovine embryos; (3) decreasing the expression of miRNA-145 by the miRNA-145 inhibitor significantly enhanced the expression of these three genes and the blastocyst formation rate; it also increased the total cell number and inner cell mass ratio of the bovine day 7 SCNT embryos. In conclusion, decreasing miRNA-145 expression might be a feasible means to enhance SCNT efficiency in bovines.