Xhex-expressing endodermal tissues are essential for anterior patterning in Xenopus.
Two regions expressing Hex in the early gastrula contribute to organizing the anterior of the vertebrate embryo. In Xenopus, these include the anterior yolky endoderm and the suprablastoporal endoderm (SBE), which is fated to form the epithelial lining of the gut. These tissues may correspond to the anterior visceral endoderm and anterior definitive endoderm of amniotes. Genetic studies in mice have demonstrated the important roles of these tissues in producing anterior identity in the adjacent neural ectoderm. In Xenopus, both the anterior endoderm and the SBE have anterior inducing properties; furthermore, the SBE can organize a full anterior-posterior axis. Inhibition of Xhex function shows that both these Xhex-expressing endodermal tissues are required for anterior development in Xenopus.
Smithers
Lucy E
LE
Section of Gene Function and Regulation, Institute of Cancer Research, 237 Fulham Road, London SW3 6JB, UK.
Jones
C Michael
CM
D000818:Animals; D001483:Base Sequence; D019521:Body Patterning; D004064:Digestive System / Q000196:embryology; D004707:Endoderm / Q000378:metabolism*; D004848:Epithelium / Q000196:embryology; D018507:Gene Expression Regulation, Developmental; D018398:Homeodomain Proteins / Q000096:biosynthesis*; D017403:In Situ Hybridization; D051379:Mice; D018345:Mice, Knockout; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D016376:Oligonucleotides, Antisense / Q000494:pharmacology; D010957:Plasmids / Q000378:metabolism; D014176:Protein Biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D014157:Transcription Factors; D014981:Xenopus; D029867:Xenopus Proteins
C513080:Hhex protein, mouse; D018398:Homeodomain Proteins; D016376:Oligonucleotides, Antisense; D014157:Transcription Factors; D029867:Xenopus Proteins; C513078:hhex protein, Xenopus