Early Endodermal Lineage Markers

Pluripotent embryonic stem (ES) cells give rise to both extraembryonic primitive endoderm and definitive endoderm. Primitive endoderm cells arise from ES cells expressing high levels of the markers GATA-4 and GATA-6, and GATA-4 remains a stable marker of lineage-committed primitive endodermal cells. Cells of the definitive endodermal lineage are fated to form the inner lining of the gut and related organs such as the liver and pancreas. During gastrulation, establishment of the definitive endoderm is dependent upon the activity of transcription factors, including members of the SOX and forkhead domain (Fox) families, which also serve as markers of definitive endoderm.