title: Analysis of HeyL expression in wild-type and Notch pathway mutant mouse embryos.
abstract: In vertebrates Notch signaling regulates cell fate decisions and boundary formation and it underlies several murine and human diseases. Gene targeting experiments point to key roles of Notch receptors, ligands, modulators and downstream targets in somitogenesis, neurogenesis and vascular development. Here we report the embryonic expression of the hairy-related basic helix-loop-helix gene HeyL in wild-type and Notch pathway mutant mice. We show that HeyL is strongly expressed in the presomitic mesoderm, the somites, the peripheral nervous system and smooth muscle of all arteries. Loss of HeyL expression at the level of nascent somites in Notch1 and Delta-like1 knockout mutants implicates HeyL as a Notch effector during somite formation. Furthermore, HeyL expression in vascular smooth muscle cells and in the thymus strikingly overlaps with that of Notch3, mutations of which underlie the CADASIL vascular disorder.
authors.affiliation: Institute of Physiological Chemistry I, Theodor-Boveri-Institute (Biocenter), University of Wuerzburg, Am Hubland, D-97074, Wuerzburg, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Leimeister
authors.forename: N
authors.initials: N
authors.lastname: Schumacher
authors.forename: C
authors.initials: C
authors.lastname: Steidl
authors.forename: M
authors.initials: M
authors.lastname: Gessler
mesh_terms: D000818:Animals; D005314:Embryonic and Fetal Development / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental; D018257:Helix-Loop-Helix Motifs / Q000235:genetics; D006801:Humans; D017403:In Situ Hybridization; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins / Q000235:genetics*; D051379:Mice; D018345:Mice, Knockout; D009154:Mutation; D051881:Receptor, Notch1; D011956:Receptors, Cell Surface; D014157:Transcription Factors / Q000235:genetics*
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; C497761:NOTCH1 protein, human; C497762:Notch1 protein, mouse; D051881:Receptor, Notch1; D011956:Receptors, Cell Surface; D014157:Transcription Factors; C064045:delta protein