The Effects of Trichostatin A on mRNA Expression of Chromatin Structure-, DNA Methylation-, and Development-Related Genes in Cloned Mouse Blastocysts

摘要

Trichostatin A (TSA) is the most potent histone deacetylase (HDAC) inhibitor known. Wenpreviously reported that treatment of mouse somatic cell nuclear-transferred (SCNT) oocytesnwith TSA significantly increased the blastocyst rate, blastocyst cell number, and full-term development.nHow TSA enhances the epigenetic remodeling ability of somatic nuclei and thenexpression of development-related genes, however, is not known. In the present study, wencompared the expression patterns of nine genes involved in chromatin structure and DNAnmethylation, and seven development-related genes in blastocysts developed from SCNTnoocytes treated with and without TSA, and in blastocysts developed in vivo and in vitro usingnreal-time reverse transcription-polymerase chain reaction. In vivo-recovered blastocystsnand blastocysts developed from TSA-treated SCNT oocytes exhibited similar expression patternsnfor Hdac1, 2, and 3, CBP, PCAF, and Dnmt3b genes compared with in vitro-developednblastocysts and blastocysts developed from SCNT oocytes without TSA treatment. There werensignificantly lower expression levels of Hdac1 and Hdac2 transcripts in TSA-treated and innvivo-recovered blastocysts than in TSA-untreated and in vitro-developed blastocysts. Thenfinding that TSA treatment of SCNT oocytes significantly upregulated Sox2 and cMyc transcriptsnin blastocysts indicated that both transcripts are TSA-responsive genes. Thus, TSAntreatment of mouse SCNT oocytes decreased the expression of chromatin structure- and DNAnmethylation-related genes, and increased the expression of Sox2 and cMyc genes in blastocysts.nSuch modifications might be a reason for the high developmental potential of mousenSCNT oocytes treated with TSA.