中文摘要：

成功的体细胞核移植（somatic cell nuclear transfer,SCNT）有赖于供体细胞的基因组通过重编程恢复到支持胚胎发育的全能性状态。但是,相比起自然受精后发生的重编程来说,要诱导一个已经分化的供体细胞重编程为全能性状态,往往在时间上和程度上都是迟滞的和不完全的。同时,DNA甲基化状况又是影响克隆胚胎发育和基因表达的关键因素之一。因此,深入研究主导DNA甲基化修饰的分子机理,探讨DNA去甲基化在供体细胞重编程过程中扮演的角色,从而进一步提高供体细胞重编程效率,提高克隆胚的发育潜能,这对于体细胞核移植效率的提高具有重要的意义。

英文摘要：

Reprogramming of a somatic nucleus to a totipotential state of supporting embryonic development is thought to be essential for successful cloning by SCNT （somatic cell nuclear transfer）. Due to the evolved capacity of oocyte in normal fertilization, SCNT-induced reprogramming of a differentiated nucleus to a totipotential state is suboptimal in comparison with adequate and appropriately timed maternal and paternal genome reprogramming ensuing normal fertilization. Meanwhile, DNA-methylation pattern is one of the key factors which affect the development of SCNT-reconstructed embryos and gene expression profile. Hence, thorough understanding of the molecular mechanism underlying DNA-methylation modification and grasp of the knowledge about the role of DNA-demethylation in reprogramming of a donor nucleus, further enhancing the efficacy of this process and the developing potential of SCNT-reconstrncted embryos are likely to have a significant impact on elevating the SCNT efficiency.