Effects Of Trichostatin A On Development And The Pattern Of Gene Expression In Mouse Preimplantation Embryos

A dramatic reprogramming of gene expression occurs during the maternal-to-zygotic transition, and this reprogramming is likely the molec μ Lar foundation for transforming the highly differentiated gamete into the totipotent blastomeres of the early cleavage stage preimplantation embryo. Histone acetylation is one of epigenetic modifications in chromatin, which can increase the access of transcriptional machinery into DNA by changing the structure of chromatin. Trichostatin A (TSA), one of the inhibitors of HDACs, was used to determine the effects of core histone hyperacetylation on development ability and expression level of relational gene mRNA in different developmental embryos.The resμLts showed that treatment of one-cell embryos with short or long time TSA did not prevent cleavage to the two-cell stage, and brief treatment with TSA did not inhibit cleavage of two-cell embryos to the four-cell stage. The persistent addition of TSA to early two-cell embryos inhibited cleavage to the four-cell stage (p<0.01), whereas its addition to late two-cell embryos did not inhibit cleavage to the four-cell stage but did inhibit further development to the eight-cell stage (p<0.01). However, brief treatment with TSA had no effect on embryo development. The expression levels of eIF-4C and hsp70.1 were increased by persistent treatment with TSA in two-cell embryo (p<0.01), but brief treatment had no effect. Moreover, the expression levels of eIF-4C and hsp70.1 in four-cell stage embryo were improved by persistent treatment (p<0.01), which was added at the time of not only early 2-cell stage but also late 2-cell stage. There is an increase in acetylation of histone H4 on lysine 12 following treatment of one-cell and two-cell embryo with persistant TSA.In conclusion, mouse embryo development and the expression level of eIF-4C and hsp70.1 during genome reprogramming can be influenced by hyeracetylation induced with TSA. And further studies are needed to reveal the functions of eIF-4C and hsp70.1 as the critical genes during cleavage of two-cell embryos to the four-cell stage.