Roles of ZIC2 in Regulation of Pluripotent Stem Cells

Pioneered by the classical mouse embryonic stem cells (ESCs), various stem cell lines representing the peri- and postimplantation stages of embryogenesis have been established. To gain insight into the gene regulatory network operating in these cells, we first investigated epiblast stem cells (EpiSCs), performing ChIP-seq analysis for five major transcription factors (TFs) involved in epiblast regulation. The analysis indicated that SOX2-POU5F1 TF pairs highlighted in mouse ESCs are not the major players in other stem cells. The major acting transcription factors shift from SOX2/POU5F1 in mouse ESCs to ZIC2/OTX2 in EpiSCs, and this shift is primed in ESCs by binding of ZIC2 at relevant genomic positions that later function as enhancers.