Effect of Xist Gene Repression on Early Development of Bovine SCNT Embryos

doi:10.13560/j.cnki.biotech.bull.1985.2015.01.033

Abstract

Abstract: Xist is an X-inactivation related gene that produces a noncoding RNA, and it is one of the first imprinted genes to be expressed in the early embryo with expression beginning at zygotic genome activation. This experiment aimed at investigating Xist repression in fetal bovine fibroblast by TALE-REPRESSOR（TALER）which contains mCherry as reporter, and the impact of Xist repression on early development of cloned cattle embryos using the transfected cells as nuclei donor. The results showed TALER repressed Xist gene expression by 93.85% in fluorescence-activated sorted cells compared with wild type fibroblast, indicating the TALER vector designed in this experiment effectively suppressed expression of Xist. The mCherry positive cells were selected for somatic cell nuclear transfer（SCNT）. The 2-cell, 8-cell, morula and blastocyst rates of suppressed group vs. control group were 78.8% vs 75.1%（P>0.05）, 54.4% vs. 50.6%（P>0.05）, 12.3% vs. 27.8%（P<0.01）and 0 vs. 26.6%（P<0.01）, respectively. These results indicated that TALER vectors effectively inhibited Xist gene expression in female fetal bovine fibroblast. Suppression of Xist gene promotes the 2-8 cell embryonic development of cloned embryo, however, development of morula/blastocyst decreased significantly. Therefore, the mechanism by which Xist gene expression regulates early embryonic development of cloned embryos needs further investigation.

Key words: Xist gene, TALER vector, fetal bovine fibroblast, early embryonic development

Liu Liming, Sun Wei, Zhang Jindun, Zhao Lixia, Li Shuyu, Wang Biao, Chen Yanglin, Hu Shuxiang, Wu Baojiang, Li Xihe. Effect of Xist Gene Repression on Early Development of Bovine SCNT Embryos[J]. Biotechnology Bulletin, 2015, 31(1): 214-219.

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