Prior to gastrulation, SOX2 is expressed throughout the epiblast (inferred from mouse embryos). During gastrulation, SOX2 becomes restricted to the anterior epiblast that develops into the anterior neural plate and the anterior part of posterior neural plate and persists in the neural tube (inferred from mouse embryos). SOX2 is considered to be the earliest marker of developing neuroectoderm (inferred from mice in Tang et al. 2015). In the anterior neural plate, first POU5F1, then POU3F1 bind the N2 enhancer with OTX2 and ZIC2 upstream of the SOX2 coding region and activate transcription of SOX2 (inferred from mouse homologs). In posterior neural plate, WNT signaling and FGF signaling act on the N1 enhancer downstream of the SOX2 coding region (inferred from mouse embryos). Forced expression of Sox2 is able to direct mouse embryonic stem cells to differentiate into neuroectoderm (Zhao et al. 2004).