Photoreceptor subtype specification: from flies to humans

Semin Cell Dev Biol. 2001 Dec;12(6):509-18. doi: 10.1006/scdb.2001.0275.


Multiple cell types often differentiate from a pluripotent cell. These cells may then further diversify as distinct subtypes. The visual system provides an ideal model for studying subtype specification as various photoreceptors acquire different functions based on the type of opsin they express. Opsin expression is mostly controlled through transcriptional mechanisms that are evolutionary conserved from Drosophila to humans. In addition, it appears that, from a "default" developmental state, distinct "acquired" photoreceptor states develop upon receiving intrinsic or extrinsic signals. This review discusses factors involved in opsin gene regulation and how their integration may explain how subtype specificity is achieved.

Publication types

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

MeSH terms

  • Animals
  • Drosophila / embryology
  • Drosophila / genetics
  • Gene Expression Regulation
  • Humans
  • Locus Control Region / physiology
  • Morphogenesis
  • Photoreceptor Cells / embryology*
  • Photoreceptor Cells / growth & development
  • Photoreceptor Cells, Vertebrate / physiology
  • Rod Opsins / genetics*


  • Rod Opsins