Primary structure of crayfish visual pigment deduced from cDNA

AbstractThe primary structure of opsin of the crayfish Procambarus clarkii has been deduced from the cDNA sequence. The opsin is composed of 376 amino acid residues including all the conservative residues characteristic of other members of the rhodopsin family. Comparison of sequences of all known opsins reveals that the major Drosophila rhodopsin is more similar to the crayfish rhodopsin than to the Drosophila UV-sensitive pigments. The phylogenetic trees of invertebrate opsins are constructed