The definitive endoderm is the embryonic germ layer that gives rise to the budding endodermal organs including the thyroid, lung, liver and pancreas as well as the remainder of the gut tube. DiI fate mapping and whole embryo culture were used to determine the endodermal origin of the 9.5 days post coitum (dpc) dorsal and ventral pancreas buds. Our results demonstrate that the progenitors of eac...

The kidney and vasculature are intimately linked both functionally and during development, when nephric and blood/vascular progenitor cells occupy adjacent bands of mesoderm in zebrafish and frog embryos. Developmental mechanisms that underlie the differentiation of kidney versus blood/vascular lineages remain unknown. The odd skipped related1 (osr1) gene encodes a zinc-finger transcription fac...

ABSTRACT Anterior mesoderm (AM) and definitive endoderm (DE) progenitors represent the earliest embryonic cell types that are specified during germ layer formation at primitive streak (PS) of mouse embryo. Genetic experiments indicate both lineages segregate from Eomes-expressing in response to different Nodal signaling levels. However, precise spatiotemporal pattern emergence these molecular d...

In this study, the initial specification of foregut endoderm in the chick embryo was analyzed. A fate map constructed for the area pellucida endoderm at definitive streak-stage showed centrally-located presumptive cells of foregut-derived organs around Hensen's node. Intracoelomic cultivation of the area pellucida endoderm at this stage combined with somatic mesoderm resulted in the differentia...

BACKGROUND Retinoic acid (RA) and fibroblast growth factor 4 (FGF4) signaling control endoderm patterning and pancreas induction/expansion. Based on these findings, RA and FGFs, excluding FGF4, have frequently been used in differentiation protocols to direct differentiation of hESCs into endodermal and pancreatic cell types. In vivo, these signaling pathways act in a temporal and concentration-...

The origin of the prelung cells was determined by tracing the movements of [H]thymidinelabelled grafts excised from medium-streak to 4-somite stage chick embryos and transplanted to the epiblast, streak, and endoderm-mesoderm of similarly staged recipient embryos. At the medium-streak stage the prelung endoderm cells are in the anterior third of the primitive streak; they shortly begin to migra...