57 GENE EXPRESSION PATTERN OF MINIATURE PIG SOMATIC CELL NUCLEAR TRANSFER EMBRYOS TREATED WITH THE HISTONE DEACETYLASE INHIBITOR SCRIPTAID

Abstract

It was recently shown that treatment of cloned embryos with histone deacetylase inhibitors improves efficiency for the success rate of developmental potential to term in several species. The objective of the present study was to investigate the influence of the histone deacetylase inhibitor Scriptaid (Sc) on in vitro development in early porcine SCNT embryos and on their gene expression pattern. Based on the findings of previous porcine studies (Zhao et al. 2009), the reconstructed oocytes were treated with 500 nM Scriptaid for 14 to 16 h after post-fusion activation (6-DMAP/demecolcine). In our preliminary study, blastocyst rate significantly increased in the Sc-treated group, compared with the control group (25.1 ± 2.8% and 13.8 ± 1.9%, respectively, P < 0.05). We determined gene expression using quantitative real-time RT-PCR. The results showed that OCT3/4 gene was expressed at a similar level in in vivo and SCNT blastocysts with/without Sc. IGF2 and H19 genes tended to be highly expressed in both SCNT blastocysts with (1.6-fold and 3.1-fold, respectively) and without (2.0-fold and 5.8-fold, respectively) Sc than that of the in vivo blastocysts. We found differences in imprinted gene expression patterns between in vivo and cloned blastocysts. Expression of H19 and IGF2 in SCNT blastocysts after Scriptaid treatment decreased towards the expression levels of in vivo blastocysts. These results indicated that Scriptaid treatment in SCNT embryos may also have beneficial effects on in vitro developmental competence as well as their gene expression pattern.