title: Regionalisation of the endoderm progenitors and morphogenesis of the gut portals of the mouse embryo.
abstract: This fate-mapping study reveals that the progenitors of all major parts of the embryonic gut are already present in endoderm of the early-head-fold to early-somite stage (1-9 somites) mouse embryo. The anterior endoderm contributes primarily to the anterior intestinal portal of the early-organogenesis stage (16-19 somites) embryo. Endoderm cells around and lateral to the node are allocated to the open "midgut" region of the embryonic gut. The posterior (post-nodal) endoderm contributes not only to the posterior intestinal portal but also the open "midgut". Descendants of the posterior endoderm span a length of the gut from the level of the 3rd-5th somites to the posterior end of the embryonic gut. The formation of the anterior and posterior intestinal portals is accompanied by similar repertoires of morphogenetic tissue movement. We also discovered that cells on contralateral sides of the anterior endoderm are distributed asymmetrically to the dorsal and ventral sides of the anterior intestinal portal, heralding the acquisition of laterality by the embryonic foregut.
authors.affiliation: Embryology Unit, Children's Medical Research Institute, University of Sydney, Locked Bag 23, Wentworthville, NSW 2145, Australia.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Franklin
authors.forename: Poh Lynn
authors.initials: PL
authors.lastname: Khoo
authors.forename: Heidi
authors.initials: H
authors.lastname: Bildsoe
authors.forename: Nicole
authors.initials: N
authors.lastname: Wong
authors.forename: Samara
authors.initials: S
authors.lastname: Lewis
authors.forename: Patrick P L
authors.initials: PP
authors.lastname: Tam
mesh_terms: D000818:Animals; D002465:Cell Movement / Q000502:physiology; D004707:Endoderm / Q000166:cytology* / Q000502:physiology; D005260:Female; D041981:Gastrointestinal Tract / Q000033:anatomy & histology* / Q000196:embryology*; D008099:Liver / Q000033:anatomy & histology / Q000196:embryology; D051379:Mice; D008815:Mice, Inbred Strains; D009024:Morphogenesis / Q000502:physiology*; D013234:Stem Cells / Q000166:cytology* / Q000502:physiology