PUBLICATION

Hedgehog signaling is required for primary motoneuron induction in zebrafish

Authors
Lewis, K.E. and Eisen, J.S.
ID
ZDB-PUB-010927-4
Date
2001
Source
Development (Cambridge, England)   128(18): 3485-3495 (Journal)
Registered Authors
Eisen, Judith S., Lewis, Katharine E.
Keywords
Hh; smoothened; motoneuron; syu; smu; cyc; flh; shh; ehh; twhh; morpholino; ventral neural tube; floor plate; spinal cord patterning
MeSH Terms
  • Animals
  • Embryonic Induction*
  • Hedgehog Proteins
  • Homeodomain Proteins/biosynthesis
  • LIM-Homeodomain Proteins
  • Motor Neurons*
  • Muscle Fibers, Slow-Twitch
  • Muscles/embryology
  • Mutation
  • Nerve Tissue Proteins*
  • Oligonucleotides, Antisense
  • Phenotype
  • Signal Transduction
  • Spinal Cord/embryology*
  • Trans-Activators/genetics
  • Trans-Activators/metabolism*
  • Transcription Factors
  • Zebrafish/embryology*
  • Zebrafish Proteins
PubMed
11566854
Abstract
Sonic hedgehog (Shh) is crucial for motoneuron development in chick and mouse. However, zebrafish embryos homozygous for a deletion of the shh locus have normal numbers of motoneurons, raising the possibility that zebrafish motoneurons may be specified differently. Unlike other vertebrates, zebrafish express three hh genes in the embryonic midline: shh, echidna hedgehog (ehh) and tiggywinkle hedgehog (twhh). Therefore, it is possible that Twhh and Ehh are sufficient for motoneuron formation in the absence of Shh. To test this hypothesis we have eliminated, or severely reduced, all three Hh signals using mutations that directly or indirectly reduce Hh signaling and antisense morpholinos. Our analysis shows that Hh signals are required for zebrafish motoneuron induction. However, each of the three zebrafish Hhs is individually dispensable for motoneuron development because the other two can compensate for its loss. Our results also suggest that Twhh and Shh are more important for motoneuron development than Ehh.
Genes / Markers
Figures
Figure Gallery
Expression
Phenotype
Mutation and Transgenics
Human Disease / Model Data
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Errata and Notes