title: Expression of the chick Sizzled gene in progenitors of the cardiac outflow tract.
abstract: The secreted Frizzled receptor related proteins (Sfrp's) belong to a protein family that comprises antagonists and modifiers of Wnt and BMP signalling. Here we report the isolation and expression pattern of the Sfrp gene "Sizzled" in the chick. Sizzled genes, as well as the closely related crescent genes, exist in the genomes of fishes, frogs and chicks, but not of mammals. The chicken Sizzled gene (Szl) is initially expressed in the anterior endoderm of gastrulating and early head fold embryos. An additional, separate expression domain develops at the posterior end of the embryo from the head process stage onwards. Szl transcripts are then detected in precardial mesodermal cells, are transiently transcribed in the straight heart tube, and later prominently in the splanchnic mesoderm surrounding the arterial pole of the developing heart, the anterior heart field. These cells are subsequently recruited to form the cardiac outflow tract. cSzl expression is downregulated when the septation of the outflow tract by neural crest derived cells begins.
authors.affiliation: Research Group Developmental Biology, Max-Planck-Institute for Biophysical Chemistry, Göttingen, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Wittler
authors.forename: Michael
authors.initials: M
authors.lastname: Saborowski
authors.forename: Michael
authors.initials: M
authors.lastname: Kessel
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D030161:Avian Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D002642:Chick Embryo; D015870:Gene Expression; D006321:Heart / Q000196:embryology*; D008969:Molecular Sequence Data; D009206:Myocardium / Q000166:cytology / Q000378:metabolism; D010802:Phylogeny; D012333:RNA, Messenger / Q000378:metabolism; D017386:Sequence Homology, Amino Acid
chemical_list: D030161:Avian Proteins; D012333:RNA, Messenger