摘要
尽管在多种哺乳动物种系中成功制备了体细胞克隆后代 ,但当前的克隆技术仍有许多亟待解决的问题。体细胞核移植胚胎大多存在许多发育异常 ,造成了妊娠早期高流产率和出生后高死亡率。有研究认为 ,克隆胚胎发育障碍的一个重要的原因是供体细胞的遗传重编程不完全。哺乳动物种系中 ,DNA甲基化是胚胎发育期转录调节的必需步骤 ,除了单拷贝基因序列外 ,在基因组很多的区域都可以观测到克隆胚胎的异常甲基化。此外 ,克隆胚胎的基因印迹也存在异常。
Although the cloned animals have been successfully generated in a number of mammalian species,there are still many problems about this technology.The developmental aberrancies include a high rate of abortion during early gestation and high rate of perinatal death.The main cause of these problems may be attributed to the epigenetic reprogramming of somatic donor genome.During mammalian embryonic development,DNA methylation is an essential process in the regulation of transcription.There are many aberrant methylation in various genomic regions of cloned embryos.The gene imprinting of cloned embryos are also abnormal.
基金
国家高技术发展计划 ( 863 )重大专项 (编号 :2 0 0 2AA2 0 662 1)基金资助~~
关键词
体细胞核移植
重编程
印迹
甲基化
somatic nuclear transfer
nuclear reprogramming
imprinting
methylation