Analysis of Cyclin E1 Functions in Porcine Preimplantation Embryonic Development by Fluorescence Microscopy

Abstract Cyclin E1 (CCNE1) is a core component of cell cycle regulation that drives the transition into the S phase. CCNE1 plays critical roles in cell cycle, cell proliferation, and cellular functions. However, the function of CCNE1 in early embryonic development is limited. In the present study, the function and expression ofCcne1in porcine early parthenotes were examined. Immunostaining experiments showed that CCNE1 localized in the nucleus, starting at the four-cell stage. Knockdown ofCcne1by double-stranded RNA resulted in the failure of blastocyst formation and induced blastocyst apoptosis.Ccne1depletion increased expression of the pro-apoptotic geneBax, and decreased the expression ofOct4and the rate of inner cell mass (ICM)/trophectoderm formation. The results indicated that CCNE1 affects blastocyst formation by inducing cell apoptosis and ICM formation during porcine embryonic development.