Effect of histone deacetylase inhibitor (Scriptaid) in two - step treatment on histone acetylation and preimplantation development of cloned bovine embryos

Abstract

This study evaluated the effect of Scriptaid (SCR), a novel Histone Deacetylases inhibitor (HDACi) with low toxicity on preimplantation developmental competence of cloned bovine embryos. In the first experiment, the optimal concentration of SCR for treating SCNT embryos was estimated, which was 250nM for 10 hours. The preimplantation development rate was significant higher compare to non-treated group. With that concentration, we used for treating the next step, which was the second experiment, to evalute the development competence when treated embryos with SCR at 72 hours after activated. The results show that Scriptaid could enhance the average intensity of H3K9 acetylation in pronuclear and 8-cell stage embryo. However when treated 2-step with SCR ,could not increase the developmental competent compare to 1-step treatment. It also indicated that highly histone acetylation in cloned bovine embryos could be harmful to development rate of embryos. Average intensity of H3K9 epigenetic marker on two-cell, four-cell, eight-cell stage were also examined the enhancing histone acetylation either the epigenetic reprogramming nucleus on the Somatic Cell Nuclear Transfer (SCNT) embryos, lead us to conclude the time of Zygotic Gene Activation (ZGA) on bovine embryos was happened till around 72 hours after activated.