Vsx-1 and Vsx-2: differential expression of two paired-like homeobox genes during zebrafish and goldfish retinogenesis

J Comp Neurol. 1997 Nov 24;388(3):495-505. doi: 10.1002/(sici)1096-9861(19971124)388:3<495::aid-cne11>3.0.co;2-l.


Vsx-1 and Vsx-2 are two homeobox genes that were cloned originally from an adult goldfish retinal library. They are members of the paired-like:CVC gene family, which is characterized by the presence of a paired homeodomain and an additional conserved region, termed the CVC domain. To analyze the possible roles for Vsx-1 and Vsx-2 in eye development, we used in situ hybridization to examine their expression patterns in zebrafish and goldfish embryos. Vsx-2 is initially expressed by proliferating neuroepithelial cells of the presumptive neural retina, then it is down-regulated as differentiation begins, and it is finally reexpressed at later stages of differentiation in a subset of cells, presumed to be bipolar cells, in the inner nuclear layer. In contrast, Vsx-1 is expressed only weakly in undifferentiated, presumptive neural retina and is then up-regulated selectively in presumptive bipolar cells at early stages of differentiation (when Vsx-2 is turned off), before decreasing to an intermediate level, which is maintained in the differentiated (adult) retina. The restricted expression patterns of Vsx-2 correspond to the observed phenotypes in mice with the ocular retardation mutation (orJ), further supporting the notion that Vsx-2 and Chx10 are homologues. The sequential complimentary and then corresponding expression patterns of Vsx-1 and Vsx-2 suggest that these similar transcription factors may be recruited for partially overlapping, but distinct, functions during the development of the retina.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Eye / embryology
  • Eye Proteins / genetics*
  • Fish Proteins*
  • Gene Expression Regulation, Developmental / physiology*
  • Genes, Homeobox*
  • Goldfish / embryology
  • Goldfish / genetics*
  • Homeodomain Proteins / genetics*
  • Molecular Sequence Data
  • Retina / embryology
  • Retina / metabolism*
  • Sequence Homology, Amino Acid
  • Zebrafish / embryology
  • Zebrafish / genetics*
  • Zebrafish Proteins*


  • Eye Proteins
  • Fish Proteins
  • Homeodomain Proteins
  • Vsx-2 protein, Carassius auratus
  • Zebrafish Proteins
  • vsx1 protein, zebrafish