Sonic hedgehog is not required for the induction of medial floor plate cells in the zebrafish.
Sonic hedgehog (Shh) is a secreted protein that is involved in the organization and patterning of several tissues in vertebrates. We show that the zebrafish sonic-you (syu) gene, a member of a group of five genes required for somite patterning, is encoding Shh. Embryos mutant for a deletion of syu display defects in patterning of the somites, the lateral floor plate cells, the pectoral fins, the axons of motorneurons and the retinal ganglion cells. In contrast to mouse embryos lacking Shh activity, syu mutant embryos do form medial floor plate cells and motorneurons. Since ectopic overexpression of shh in zebrafish embryos does not induce ectopic medial floor plate cells, we conclude that shh is neither required nor sufficient to induce this cell type in the zebrafish.
Schauerte
H E
HE
Max-Planck-Institut für Entwicklungsbiologie, Spemannstrasse 35/III, Germany.
van Eeden
F J
FJ
Fricke
C
C
Odenthal
J
J
Strähle
U
U
Haffter
P
P
D000818:Animals; D001369:Axons; D019521:Body Patterning; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000096:biosynthesis; D004627:Embryonic Induction; D005123:Eye / Q000196:embryology; D005136:Eye Proteins; D005816:Genetic Complementation Test; D053823:Hedgehog Proteins; D018398:Homeodomain Proteins / Q000096:biosynthesis; D009132:Muscles / Q000166:cytology; D009154:Mutation; D009420:Nervous System / Q000196:embryology*; D009421:Nervous System Malformations; D051762:PAX2 Transcription Factor; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors; D021382:Protein Sorting Signals / Q000235:genetics; D011506:Proteins / Q000378:metabolism*; D012326:RNA Splicing; D012097:Repressor Proteins; D012165:Retinal Ganglion Cells; D017422:Sequence Analysis, DNA; D015398:Signal Transduction; D019170:Somites; D013234:Stem Cells; D015534:Trans-Activators; D014157:Transcription Factors / Q000096:biosynthesis; D015027:Zebrafish / Q000196:embryology*; D029961:Zebrafish Proteins
D004268:DNA-Binding Proteins; D005136:Eye Proteins; D053823:Hedgehog Proteins; D018398:Homeodomain Proteins; D051762:PAX2 Transcription Factor; D000071841:PAX6 Transcription Factor; D051761:Paired Box Transcription Factors; C000605732:Pax6 protein, mouse; D021382:Protein Sorting Signals; D011506:Proteins; D012097:Repressor Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D029961:Zebrafish Proteins; C106185:engrailed homeobox proteins; C497320:pax2a protein, zebrafish; D017868:Cyclic AMP-Dependent Protein Kinases