DUXA regulates the early development of porcine cloned embryos

Abnormal zygotic genome activation (ZGA) during the early development of somatic cell nuclear transfer (SCNT) embryos is one of the main reasons for the low cloning efficiency. The double homeobox (DUX) family, which includes important transcription factors in mammals, has been shown to play an important role in the ZGA process in mice. However, the role of DUXA, a member of the DUX family, in the early development of porcine somatic cloned embryos is unknown. Here, CRISPR/Cas9 gene editing and lentiviral infection technologies were used to construct stable DUXA knockout and overexpression cell lines for the production of SCNT embryos. Compared with that of wild-type (WT) SCNT embryos, the blastocyst rate of DUXA knockout embryos was significantly lower (P < 0.05), whereas the blastocyst rate of DUXA-overexpressing embryos was significantly greater (P < 0.05). Moreover, RT‒qPCR results revealed that DUXA knockout significantly reduced the expression levels of ZGA-related genes (TDG, SNAI1, RSRP1, TFAP2C, ZSCAN4, LEUTX, and KLF17) (P < 0.05). Additionally, in DUXA-overexpressing embryos, the mRNA levels of TDG, SNAI1, RSRP1, and TFAP2C significantly decreased (P < 0.05), whereas the ZSCAN4, LEUTX, and KLF17 mRNA levels increased (P < 0.05). These findings suggest that DUXA regulates the early development of porcine SCNT embryos by modulating the expression of ZGA-related genes. This research provides significant insights into the potential mechanisms of early embryo loss in porcine SCNT.