Molecular Cloning of Drosophila Rh6 Rhodopsin: The Visual Pigment of a Subset of R8 Photoreceptor Cells

FEBS Lett. 1997 Apr 7;406(1-2):6-10. doi: 10.1016/s0014-5793(97)00210-x.

Abstract

By screening retinal cDNA libraries for photoreceptor-specifically expressed genes we have isolated and sequenced a cDNA clone encoding the rhodopsin (Rh6) of a subset of R8 photoreceptor cells of the Drosophila compound eye. Compared to the other visual pigments of Drosophila, this rhodopsin is equally homologous to Rh1 and Rh2 (51% amino acid identity) but shows only 32% and 33% amino acid identity with Rh3 and Rh4, respectively. The open reading frame codes for a protein of 369 amino acids (MW = 41691). The primary structure of Rh6 displays sites typical for rhodopsin molecules in general, for example, a chromophore binding site in transmembrane domain VII, sequence motifs in the intracellular loops 2 and 3 required for the binding of a heterotrimeric G-protein, and a glycosylation site near the N-terminus which seems to be important for protein transport and maturation. Since R8 cells are founder cells in the developing compound eye, the isolation of a rhodopsin gene expressed in these cells may aid the understanding of terminal differentiation of photoreceptor cells.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Cloning, Molecular
  • DNA, Complementary
  • Drosophila Proteins*
  • Drosophila melanogaster / genetics*
  • Molecular Sequence Data
  • Photoreceptor Cells, Invertebrate / metabolism*
  • Pigments, Biological / genetics*
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Rhodopsin / genetics*
  • Sequence Homology, Amino Acid

Substances

  • DNA, Complementary
  • Drosophila Proteins
  • Pigments, Biological
  • RNA, Messenger
  • Rh6 protein, Drosophila
  • Rhodopsin

Associated data

  • GENBANK/Z86118