A novel rod-like opsin isolated from the extra-retinal photoreceptors of teleost fish

FEBS Lett. 2000 Feb 25;468(2-3):181-8. doi: 10.1016/s0014-5793(00)01217-5.


We have isolated a novel opsin from the pineal complex of Atlantic salmon (Salmo salar) and from the brain of the puffer fish (Fugu rubripes). These extra-retinal opsins share approximately 74% identity at the nucleotide and amino acid level with rod-opsins from the retina of these species. By PCR, we have determined that the novel rod-like opsin is not expressed in the salmon retina, and the retinal rod-opsin is not expressed in the salmon pineal. Phylogenetic analysis suggests that the rod-like opsins arose from a gene duplication event approximately 205 million years ago, a time of considerable adaptive radiation of the bony fish. In view of the large differences in the coding sequences of the pineal/brain rod-like opsins, their extra-retinal sites of expression, and phylogenetic position we have termed these novel opsins 'extra-retinal rod-like opsins' (ERrod-like opsins). We speculate that the differences between retinal rod-opsins and ERrod-like opsins have arisen from their differing photosensory roles and/or genetic drift after the gene duplication event in the Triassic.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Brain Chemistry
  • Cattle
  • Evolution, Molecular
  • Fishes / genetics*
  • Gene Duplication
  • Gene Library
  • Molecular Sequence Data
  • Photoreceptor Cells, Vertebrate / chemistry*
  • Phylogeny*
  • Pineal Gland / chemistry
  • Retina / chemistry*
  • Retinal Rod Photoreceptor Cells / chemistry
  • Rod Opsins / chemistry*
  • Rod Opsins / genetics*
  • Rod Opsins / isolation & purification
  • Salmo salar / genetics
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Sharks
  • Species Specificity


  • Rod Opsins