Pluripotent lineages in the mouse embryo A Morula B Early blastocyst C Late blastocyst D Egg cylinder stage Oct3/4 Inner cell mass Nanog Epiblast Primitive Germ cell (ICM) ectone line Somatic cell Visceral lineages Ectoderm endoderm Blastocyst Endoderm cavity Primitive Parietal Gata6 endoderm endoderm Proamniotic Trophectoderm Extraembryonic cavity Cdx2 ectodermPluripotentlineages in the mouse embryo