title: A gene trap integration provides an early in situ marker for hepatic specification of the foregut endoderm.
abstract: We report the characterization of a gene trap integration that provides an in situ marker for one of the earliest events in liver development. Expression of the reporter gene is observed at the nine-somite stage in the hepatic field of the foregut endoderm. At 10.5 days post-coitus expression is observed exclusively and at high levels in the majority of cells in the developing liver bud. As development proceeds the proportion of expressing cells decreases with expression in adult liver being restricted to a few sporadic cells. This therefore provides the earliest, most specific in situ marker of the hepatic lineage reported to date and will be useful in the further characterization of the inductive events involved in hepatic specification. Molecular characterization of the gene trap insertion suggests that the expression pattern is the result of alternative promoter use in the ankyrin repeat-containing gene, gtar.
authors.affiliation: Centre for Genome Research, University of Edinburgh, Kings Buildings, West Mains Road, EH9 3JQ, Edinburgh, UK.
authors.forename: A J
authors.initials: AJ
authors.lastname: Watt
authors.forename: E A
authors.initials: EA
authors.lastname: Jones
authors.forename: J M
authors.initials: JM
authors.lastname: Ure
authors.forename: D
authors.initials: D
authors.lastname: Peddie
authors.forename: D I
authors.initials: DI
authors.lastname: Wilson
authors.forename: L M
authors.initials: LM
authors.lastname: Forrester
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D019070:Cell Lineage; D003001:Cloning, Molecular; D003433:Crosses, Genetic; D018076:DNA, Complementary / Q000378:metabolism; D004268:DNA-Binding Proteins; D004064:Digestive System / Q000196:embryology*; D004622:Embryo, Mammalian / Q000378:metabolism; D004707:Endoderm / Q000502:physiology*; D005260:Female; D005819:Genetic Markers; D017404:In Situ Hybridization, Fluorescence; D008099:Liver / Q000196:embryology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008957:Models, Genetic; D008969:Molecular Sequence Data; D010641:Phenotype; D011401:Promoter Regions, Genetic; D014176:Protein Biosynthesis; D020033:Protein Isoforms; D011506:Proteins / Q000737:chemistry / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism; D016601:RNA-Binding Proteins; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012260:Ribonucleases / Q000378:metabolism; D013234:Stem Cells / Q000378:metabolism; D013997:Time Factors
chemical_list: C481273:ANKRD17 protein, human; C426849:Ankrd17 protein, mouse; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D005819:Genetic Markers; D020033:Protein Isoforms; D011506:Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D012260:Ribonucleases