PUBLICATION

Involvement of Pax6 and Otx2 in the forebrain-specific regulation of the vertebrate homeobox gene ANF/Hesx1

Authors
Spieler, D., Bäumer, N., Stebler, J., Köprunner, M., Reichman-Fried, M., Teichmann, U., Raz, E., Kessel, M., and Wittler, L.
ID
ZDB-PUB-040429-2
Date
2004
Source
Developmental Biology   269(2): 567-579 (Journal)
Registered Authors
Köprunner, Marion, Raz, Erez, Reichman-Fried, Michal
Keywords
Promoter, Transcription, Prosencephalon, DNA binding, Chick, Zebrafish, Mouse
MeSH Terms
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Basic Helix-Loop-Helix Transcription Factors
  • Chick Embryo
  • Conserved Sequence
  • Eye Proteins
  • Gene Expression Regulation, Developmental
  • Genes, Homeobox*
  • Homeodomain Proteins/chemistry
  • Homeodomain Proteins/genetics*
  • Homeodomain Proteins/physiology*
  • Mice
  • Molecular Sequence Data
  • Nerve Tissue Proteins/physiology*
  • Otx Transcription Factors
  • Paired Box Transcription Factors
  • Promoter Regions, Genetic
  • Prosencephalon/embryology*
  • Prosencephalon/metabolism
  • Repressor Proteins
  • Trans-Activators/physiology*
  • Zebrafish
  • Zebrafish Proteins
PubMed
15110720 Full text @ Dev. Biol.
Abstract
During early vertebrate development, ANF homeobox genes are expressed in the prospective forebrain. Their regulation is essential for correct morphogenesis and function of the prosencephalon. We identified a 1-kb fragment upstream of the chicken GANF gene sufficient to drive lacZ expression in the endogenous expression domain. Concordant with the high conservation of this sequence in five investigated species, this element is also active in the corresponding expression domain of the zebrafish orthologue. In vivo analysis of two in vitro-identified Otx2 binding sites in this conserved sequence revealed their necessity for activation of the chicken ANF promoter. In addition, we identified a Pax6-binding site close to the transcriptional start site that is occupied in vivo by Pax6 protein. Pax6 and GANF exhibit mutually exclusive expression domains in the anterior embryonic region. Overexpression of Pax6 in chick embryos inhibited the endogenous GANF expression, and in Pax6(-/-) mice the expression domain of the murine ANF orthologue Hesx1 was expanded and sustained, indicating inhibitory effects of Pax6 on GANF. However, a mutation of the Pax6 site did not abolish reporter activity from an electroporated vector. We conclude that Otx2 and Pax6 are key molecules involved in conserved mechanisms of ANF gene regulation.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping