In early embryogenesis, the posteroventral foregut endoderm gives rise 22 to the budding endodermal organs including the liver, ventral pancreas and gallbladder 23 during early somitogenesis. Despite the detailed fate maps of the liver and pancreatic 24 progenitors in the mouse foregut endoderm, the exact location of the gallbladder 25 progenitors remains unclear. In this study, we performed a ...

move inwards on the surface of, yet solid, oral endoderm. On the basis of this movement, ectoderm cells become the basal layer, whereas endoderm cells become the apical layer of the definite oral epithelium. As a direct consequence, the endoderm cells are observed even at an outer lip surface outside of mouth, as well as significantly contribute to tooth anlagen. This alternative mode of axolot...

move inwards on the surface of, yet solid, oral endoderm. On the basis of this movement, ectoderm cells become the basal layer, whereas endoderm cells become the apical layer of the definite oral epithelium. As a direct consequence, the endoderm cells are observed even at an outer lip surface outside of mouth, as well as significantly contribute to tooth anlagen. This alternative mode of axolot...

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...

At E4.0 the inner cell mass of the mouse blastocyst consists of a core of embryonic ectoderm cells surrounded by an outer layer of primitive (extraembryonic) endoderm, which subsequently gives rise to both visceral endoderm and parietal endoderm. Shortly after blastocyst implantation, the solid mass of ectoderm cells is converted by a process known as cavitation into a pseudostratified columnar...

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-...

To study the developmental origin of the pancreas we used DiI crystals to mark regions of the early chick endoderm: this allowed correlations to be established between specific endoderm sites and the positions of their descendants. Endodermal precursor cells for the stomach, pancreas and intestine were found to segregate immediately after completion of gastrulation. Transplantation experiments ...

The homeobox gene Hex is expressed in the anterior visceral endoderm (AVE) and rostral definitive endoderm of early mouse embryos. Later, Hex transcripts are detected in liver, thyroid and endothelial precursor cells. A null mutation was introduced into the Hex locus by homologous recombination in embryonic stem cells. Hex mutant embryos exhibit varying degrees of anterior truncation as well as...

In order to determine the origin of blood cells we performed embryonic grafts of different portions of mesoderm from various locations between diploid and tetraploid embryos at the tail-bud stage. The tetraploid animals were the hosts. The size differences between tetraploid and diploid cells made identification possible by direct microscopic examination of blood smears. In a previous report we...