ZFIN ID: ZDB-PUB-980820-3
Molecular identification of spadetail: regulation of zebrafish trunk and tail mesoderm formation by T-box genes
Griffin, K.J.P., Amacher, S.L., Kimmel, C.B., and Kimelman, D.
Date: 1998
Source: Development (Cambridge, England)   125: 3379-3388 (Journal)
Registered Authors: Amacher, Sharon, Griffin, Kevin, Kimelman, David, Kimmel, Charles B.
Keywords: spadetail; brachyury; no tail; tbx6; posterior development; FGF; zebrafish; T-box
MeSH Terms:
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cloning, Molecular
  • DNA Primers/genetics
  • DNA-Binding Proteins/genetics
  • DNA-Binding Proteins/physiology
  • Fetal Proteins*
  • Fibroblast Growth Factors/physiology
  • Gene Expression Regulation, Developmental
  • In Situ Hybridization
  • Mesoderm/cytology
  • Mesoderm/physiology
  • Models, Genetic
  • Molecular Sequence Data
  • Mutation
  • Phenotype
  • Polymerase Chain Reaction
  • Sequence Homology, Amino Acid
  • Signal Transduction
  • T-Box Domain Proteins
  • Tail/embryology
  • Transcription Factors/genetics*
  • Transcription Factors/physiology
  • Vertebrates/embryology
  • Vertebrates/genetics
  • Zebrafish/embryology*
  • Zebrafish/genetics*
  • Zebrafish/physiology
  • Zebrafish Proteins*
PubMed: 9693141
Inhibition of fibroblast growth factor (FGF) signaling prevents trunk and tail formation in Xenopus and zebrafish embryos. While the T-box transcription factor Brachyury (called no tail in zebrafish) is a key mediator of FGF signaling in the notochord and tail, the pathways activated by FGF in non-notochordal trunk mesoderm have been uncertain. Previous studies have shown that the spadetail gene is required for non-notochordal trunk mesoderm formation; spadetail mutant embryos have major trunk mesoderm deficiencies, but relatively normal tail and notochord development. We demonstrate here that spadetail encodes a T-box transcription factor with homologues in Xenopus and chick. Spadetail is likely to be a key mediator of FGF signaling in trunk non-notochordal mesoderm, since spadetail expression is regulated by FGF signaling. Trunk and tail development are therefore dependent upon the complementary actions of two T-box genes, spadetail and no tail. We show that the regulatory hierarchy among spadetail, no tail and a third T-box gene, tbx6, are substantially different during trunk and tail mesoderm formation, and propose a genetic model that accounts for the regional phenotypes of spadetail and no tail mutants.