title: cash4, a novel achaete-scute homolog induced by Hensen's node during generation of the posterior nervous system.
abstract: In vertebrate embryos, the precursor cells of the central nervous system (CNS) are induced by signaling from the organizer region. Here we report the isolation of a novel vertebrate achaete-scute homolog, cash4, which is expressed in the presumptive posterior nervous system in response to such signaling. cash4 is first expressed in epiblast cells flanking the late-phase organizer (Hensen's node), which retains its ability to induce cash4 during regression to the caudal end of the embryo. We show that these node-derived signals can be mimicked in vivo by the activity of fibroblast growth factor (FGF). We demonstrate that cash4 can substitute for the achaete/scute genes in the fly and that it also has proneural activity in vertebrate embryos. Together these results suggest that cash4 functions as a proneural gene downstream of node-derived signals (including FGF) to promote the formation of the neural precursors that will give rise to the posterior CNS in the chick embryo.
authors.affiliation: Developmental Genetics, Imperial Cancer Research Fund, London, UK.
authors.forename: D
authors.initials: D
authors.lastname: Henrique
authors.forename: D
authors.initials: D
authors.lastname: Tyler
authors.forename: C
authors.initials: C
authors.lastname: Kintner
authors.forename: J K
authors.initials: JK
authors.lastname: Heath
authors.forename: J H
authors.initials: JH
authors.lastname: Lewis
authors.forename: D
authors.initials: D
authors.lastname: Ish-Horowicz
authors.forename: K G
authors.initials: KG
authors.lastname: Storey
mesh_terms: D000595:Amino Acid Sequence; D000663:Amphibians / Q000196:embryology / Q000235:genetics; D000818:Animals; D030161:Avian Proteins; D051792:Basic Helix-Loop-Helix Proteins; D002454:Cell Differentiation / Q000235:genetics; D002490:Central Nervous System / Q000196:embryology*; D002642:Chick Embryo / Q000166:cytology / Q000502:physiology*; D003001:Cloning, Molecular; D018076:DNA, Complementary; D004268:DNA-Binding Proteins / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D004330:Drosophila / Q000196:embryology / Q000235:genetics; D029721:Drosophila Proteins; D004625:Embryo, Nonmammalian / Q000502:physiology; D004627:Embryonic Induction / Q000235:genetics; D005314:Embryonic and Fetal Development / Q000235:genetics; D005346:Fibroblast Growth Factors / Q000494:pharmacology; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism
chemical_list: D030161:Avian Proteins; D051792:Basic Helix-Loop-Helix Proteins; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D005346:Fibroblast Growth Factors; D011994:Recombinant Proteins; D014157:Transcription Factors; C099107:CASH-1 protein, Gallus gallus; C105240:CASH4 protein, Gallus gallus; C089199:ac protein, Drosophila; C089197:sc protein, Drosophila