A novel subtype of G-protein-coupled receptor kinase, GRK7, in teleost cone photoreceptors

FEBS Lett. 1998 Mar 13;424(3):159-64. doi: 10.1016/s0014-5793(98)00162-8.


Two kinds of retinal cDNA fragments (OIGRK-R and -C) encoding the putative G-protein-coupled receptor kinases (GRKs) were isolated from medaka, Oryzias latipes. OIGRK-R appears to be closely related to the rhodopsin kinase (RK) found in the outer segments of mammalian photoreceptors, but the deduced amino acid sequence of OIGRK-C shows less than 50% identity to those of GRKs known to date, suggesting that OIGRK-C is a novel GRK subtype (GRK7). The mRNA of OIGRK-R is detectable in rods, and that of OIGRK-C is found in all four types of cone photoreceptor. The C-terminal of OIGRK-R has a consensus sequence for farnesylation, whereas, surprisingly, OIGRK-C has a consensus sequence for geranylgeranylation. Our result are consistent with the concept that lower vertebrates have rod- and cone-specific opsin kinases.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • DNA, Complementary / isolation & purification
  • In Situ Hybridization / methods
  • Lizards / physiology
  • Molecular Sequence Data
  • Oryzias / physiology*
  • Phylogeny
  • Protein-Serine-Threonine Kinases*
  • Receptor Protein-Tyrosine Kinases / genetics*
  • Receptor Protein-Tyrosine Kinases / metabolism*
  • Retina / enzymology
  • Retinal Cone Photoreceptor Cells / enzymology*
  • Retinal Rod Photoreceptor Cells
  • Salamandridae / physiology
  • Sequence Homology, Amino Acid


  • DNA, Complementary
  • Receptor Protein-Tyrosine Kinases
  • Protein-Serine-Threonine Kinases

Associated data

  • GENBANK/AB009568
  • GENBANK/AB009569
  • GENBANK/AB009570
  • GENBANK/AB009571
  • GENBANK/AB009572
  • GENBANK/AB009573