ZFIN ID: ZDB-PUB-030319-1
Two tcf3 genes cooperate to pattern the zebrafish brain
Dorsky, R.I., Itoh, M., Moon, R.T., and Chitnis, A.
Date: 2003
Source: Development (Cambridge, England)   130(9): 1937-1947 (Journal)
Registered Authors: Chitnis, Ajay, Dorsky, Richard, Itoh, Motoyuki, Moon, Randall T.
Keywords: none
MeSH Terms:
  • Amino Acid Sequence
  • Animals
  • Brain/embryology*
  • Cytoskeletal Proteins
  • HMGB Proteins/genetics*
  • HMGB Proteins/metabolism
  • Molecular Sequence Data
  • Mutation
  • Phenotype
  • Proteins/metabolism
  • RNA, Antisense
  • TCF Transcription Factors
  • Transcription Factor 7-Like 1 Protein
  • Transcription Factors/genetics*
  • Transcription Factors/metabolism
  • Wnt Proteins
  • Zebrafish/embryology*
  • Zebrafish Proteins
PubMed: 12642497 Full text @ Development
Caudalizing factors operate in the context of Wnt/beta-catenin signaling to induce gene expression in discrete compartments along the rostral-caudal axis of the developing vertebrate nervous system. In zebrafish, basal repression of caudal genes is achieved through the function of Headless (Hdl), a Tcf3 homolog. In this study, we show that a second Tcf3 homolog, Tcf3b, limits caudalization caused by loss of Hdl function and although this Lef/Tcf family member can rescue hdl mutants, Lef1 cannot. Wnts can antagonize repression mediated by Tcf3 and this derepression is dependent on a Tcf3 beta-catenin binding domain. Systematic changes in gene expression caused by reduced Tcf3 function help predict the shape of a caudalizing activity gradient that defines compartments along the rostral-caudal axis. In addition, Tcf3b has a second and unique role in the morphogenesis of rhombomere boundaries, indicating that it controls multiple aspects of brain development.