NANOG-OCT4-SOX2 Regulatory Module in Human Embryonic Stem Cells (dataset 4). Homo sapiens

The transcription factors Nanog, Oct4 and Sox2 are the master regulators of pluripotency in mouse embryonic stem cells (mESCs), however, their functions in human ESCs (hESCs) have not been rigorously defined. Here we show that the requirements for NANOG, OCT4 and SOX2 in hESCs differ from those in mESCs. Both NANOG and OCT4 are required for self-renewal and repress differentiation. OCT4 controls both extraembryonic and epiblast-derived cell fates in a BMP4-dependent manner. OCT4-depleted hESCs commit to trophectoderm and primitive endoderm in the presence of BMP4, but undergo neuroectoderm differentiation in the absence of BMP4. NANOG represses neuroectoderm and neural crest commitment, but has little or no effect on the other lineages. We find that SOX2 is not required for self-renewal because it is redundant with SOX3, which is induced in SOX2-depleted hESCs. Simultaneous depletion of both SOX2 and SOX3 induces differentiation into the primitive streak. Unexpectedly, we identify significant variability in the usage of pluripotency factors by individual hESC lines, suggesting that the pluripotency network is remodelled to support a continuum of developmental states. Our study revises the general view of how NANOG, OCT4 and SOX2 orchestrate self-renewal in hESCs. Overall design: Total RNA obtained from EF1a-control-, OE-NANOG-, OE-OCT4- or OE-SOX2-transduced hESCs.

转录因子（transcription factor）Nanog、Oct4及Sox2是小鼠胚胎干细胞（mouse embryonic stem cells, mESCs）多能性的核心调控因子，然而它们在人类胚胎干细胞（human ESCs, hESCs）中的功能尚未得到严谨界定。
本研究证实，hESCs中NANOG、OCT4及Sox2的必需性与mESCs存在显著差异。NANOG与OCT4均为维持hESCs自我更新所必需，且可抑制细胞分化。OCT4以骨形态发生蛋白4（bone morphogenetic protein 4, BMP4）依赖的方式，调控胚外及上胚层来源的细胞命运：在BMP4存在的条件下，OCT4敲减的hESCs会定向分化为滋养外胚层与原始内胚层；而在BMP4缺失时，则会向神经外胚层分化。NANOG可抑制神经外胚层及神经嵴的细胞定向，但对其他细胞谱系几乎无影响。
研究发现，SOX2并非维持hESCs自我更新所必需，因其与SOX3存在功能冗余——在SOX2敲减的hESCs中，SOX3的表达会被诱导上调。
同时敲减SOX2与SOX3会诱导hESCs向原条层分化。
出乎意料的是，我们发现不同hESC细胞系对多能性因子的使用存在显著差异，这提示多能性调控网络发生重塑，以支持一系列连续的发育状态。
本研究修正了学界关于NANOG、OCT4及Sox2如何协同调控hESCs自我更新的普遍认知。
整体实验设计：提取自转导EF1a对照、过表达NANOG（OE-NANOG）、过表达OCT4（OE-OCT4）或过表达Sox2（OE-SOX2）的hESCs的总RNA。