title: Floor plate and motor neuron induction by vhh-1, a vertebrate homolog of hedgehog expressed by the notochord.
abstract: The differentiation of distinct cell types in the ventral neural tube depends on local inductive signals from the notochord. We have isolated a vertebrate homolog of the Drosophila segment polarity gene hedgehog (hh) from zebrafish and rat, termed vhh-1. vhh-1 is expressed in the node, notochord, floor plate, and posterior limb bud mesenchyme. Each of these cell groups has floor plate inducing activity, suggesting that the vhh-1 gene may encode a floor plate-inducing molecule. Widespread expression of rat vhh-1 in frog embryos leads to ectopic floor plate differentiation in the neural tube. In vitro tests for the signaling functions of vhh-1 demonstrate that COS cells expressing the rat vhh-1 gene induce floor plate and motor neuron differentiation in neural plate explants. vhh-1 may, therefore, contribute to the floor plate and motor neuron inducing activities of the notochord.
authors.affiliation: Howard Hughes Medical Institute, Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York 10032.
authors.forename: H
authors.initials: H
authors.lastname: Roelink
authors.forename: A
authors.initials: A
authors.lastname: Augsburger
authors.forename: J
authors.initials: J
authors.lastname: Heemskerk
authors.forename: V
authors.initials: V
authors.lastname: Korzh
authors.forename: S
authors.initials: S
authors.lastname: Norlin
authors.forename: A
authors.initials: A
authors.lastname: Ruiz i Altaba
authors.forename: Y
authors.initials: Y
authors.lastname: Tanabe
authors.forename: M
authors.initials: M
authors.lastname: Placzek
authors.forename: T
authors.initials: T
authors.lastname: Edlund
authors.forename: T M
authors.initials: TM
authors.lastname: Jessell
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002454:Cell Differentiation; D002642:Chick Embryo; D017931:DNA Primers / Q000737:chemistry; D029721:Drosophila Proteins; D004627:Embryonic Induction; D005121:Extremities / Q000196:embryology; D015870:Gene Expression; D053823:Hedgehog Proteins; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D009046:Motor Neurons / Q000166:cytology; D009420:Nervous System / Q000196:embryology*; D011506:Proteins / Q000737:chemistry / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D012995:Solubility; D015534:Trans-Activators; D014982:Xenopus laevis; D015027:Zebrafish / Q000235:genetics; D029961:Zebrafish Proteins
chemical_list: D017931:DNA Primers; D029721:Drosophila Proteins; D053823:Hedgehog Proteins; D011506:Proteins; D012333:RNA, Messenger; C524053:Shha protein, zebrafish; D015534:Trans-Activators; D029961:Zebrafish Proteins; C077245:hh protein, Drosophila