Floor plate and motor neuron induction by vhh-1, a vertebrate homolog of hedgehog expressed by the notochord.
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.
Roelink
H
H
Howard Hughes Medical Institute, Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York 10032.
Augsburger
A
A
Heemskerk
J
J
Korzh
V
V
Norlin
S
S
Ruiz i Altaba
A
A
Tanabe
Y
Y
Placzek
M
M
Edlund
T
T
Jessell
T M
TM
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
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