Parallel analysis of H3K9ac reveals Dux-dependent 2C activation deficiency in mouse SCNT embryos

Somatic cell nuclear transfer (SCNT) enables gaining of totipotency by reprogramming nuclei of terminally differentiated donor cell. Recent studies have clearly demonstrated that intervention of epigenetic networks can significantly elevate both in vitro and in vivo development potential of NT embryos. Specifically, trichostatin A (TSA), a kind of histone deacetylase inhibitors (HDACi), was proved to functionally works during cloning in various mammal systems. However, how it modulates histone acylation lacks careful illustration. Here, we systematically evaluate the effect and limitation of TSA during SCNT embryo development by generating genome-wide H3K9ac maps. In addition, a Dux-dependent 2-cell (2C) activation deficiency is observed in SCNT embryos as compared with their natural fertilized counterparts. Strikingly, a refined Dux supplement can successfully assist SCNT embryos in overcoming the 2C activation defect and further promotes the overall cloning efficiency. Together, our study for the first time reveals the regulation mechanism of histone marker H3K9ac in SCNT and provides the new insight of Dux during embryogenesis. Examination of H3K9ac in IVF/NF and SCNT mouse preimplantation embryos.