VPA selectively regulates pluripotency gene expression on donor cell and improve SCNT embryo development.

Abstract

SCNT technology has been successfully used to clone a variety of mammals, but the cloning efficiency is very low. This low efficiency is likely due to the incomplete reprogramming of SCNT embryos. Histone modification and DNA methylation may participate in these events. Thus, it would be interesting to attempt to improve the efficiency of SCNT by using a HDACi VPA. In order to guarantee the effect of VPA and reduce its cytotoxicity, a comprehensive analysis of the cell proliferation and histone modification was performed. The results showed that 0.5 and 1mM VPA treatment for 24h were the optimal condition. According to the results, H3K4me3 was increased in 0.5 and 1mM VPA groups, whereas H3K9me2 was significantly decreased. These are the signals of gene-activation. In addition, VPA treatment led to the overexpression of Oct4 and Nanog. These indicated that VPA-treated cells had similar patterns of histone to zygotic embryos, and may be more favorable for reprograming. A total of 833 cloned embryos were produced from the experimental replicates of VPA-treated donor cells. In 1mM treatment group, the blastocyst rates were significantly increased compared with control. At the same time, our findings demonstrated the interrelation between DNA methylation and histone modifications.