Early Ectodermal Lineage Markers

The ectoderm is the first germ layer to emerge during gastrulation. Early ectodermal lineage cells can be identified by the expression of markers such as the transcription factor, Otx2. Subsequent activation of specific gene expression profiles induces further ectodermal lineage restriction. For example, FGF signaling and Pax6 expression in pluripotent stem cells induce early neuroectoderm differentiation, while BMP-4 treatment induces surface ectoderm differentiation in human pluripotent stem cells.