Oct4调节胚胎干细胞全能性扩增的研究进展

Progress on totipotent proliferation of embryonic stem cell regulated by Oct4

Oct4是一种POU转录因子 ,属于Ⅴ类POU蛋白 ,在小鼠全能胚胎干细胞和生殖系干细胞表达。在早期鼠胚中 ,只有在ICM变成滋养层阶段 ,Oct4为维持其全能表型而发挥作用。Oct4表达可能是由位置效应引起的 ,还与特异调节Oct4活性的元件 ,如近端、远端增强子元件有关。Oct4对转录的调节分为抑制转录和转录激活两种。Oct4的激活有 3种模式 :远端依赖性共激活 ,构象依赖性共激活 。

The Oct4,a POU transcription factor belongs to class Ⅴ of POU proteins, is expressed in mouse totipotent embryonic stem and germ cells. Oct4 plays a critical role in maintaining pluripotency of stem cell when it differentiates into a trophectoderm lineage at early stage of mouse embryo. Oct4 expression appears to be regulated by a positional effect as well as specific regulating elements of Oct4 such as proximal enhancer (PE) and distal enhancer (DE). Oct4 has both repression and activation effects in regulating transcription,and the activation has 3 models: distance dependent transactivation, conformational transactivation and Oct4 dimers dependent transactivation.