维持胚胎干细胞多能性和自我更新的转录因子Oct-4/Nanog以及相关的调控网络

Two vital transcriptional factors Oct-4 and Nanog to keep the pluripotency and self-renewal of stem cells and related regulation network

Oct-4和Nanog是两种维持干细胞多能性和自我更新的转录因子,它们通过结合靶基因调控区,选择性地抑制分化基因表达或促进多能性基因表达。它们通常只在多能干细胞中表达,在分化细胞中不表达。在不同的发育阶段,它们的表达量受到特异调控,并且分别与Sox-2、FoxD3等其他转录因子以及LIF、BMP等胞外信号通路互相作用,形成一个复杂的转录调节crosstalk网络,在特异时空激活或抑制靶基因的转录;通过互相制约最终决定干细胞是保持多能性还是分化,以及向哪个方向分化。此外,Oct-4和Nanog对体细胞重编程为多能细胞也有重要作用。

Oct-4 and Nanog are two critical transcriptional factors to keep pluripotency and self-renewal of stem cells in vivo and in vitro, and they usually express only in pluripotent cells and not in differentiated cells. They bind to the regulatory regions of targeted gene and often interact with other transcriptional factors and extracellular signal path components, such as Sox-2, FoxD3, LIF and BMP in specific tissues or developmental stages. So that all of these constitute a transcriptional erosstalk, and finally determine the cells destiny： keeping pluripotency or turning to differentiation.