Characterization of Lamprey Rhodopsin by Isolation from Lamprey Retina and Expression in Mammalian Cells

Abstract— A visual pigment was extracted from lamprey retina and was expressed in cultured mammalian cells (293S) using a cDNA fragment isolated from lamprey retina. The extracted pigment, a putative lamprey rhodopsin, had an absorption maximum at 503 nm. The recombinant lamprey rhodopsin, reconstituted with 11- cis -retinal, showed an absorption maximum at about 500 nm. Both pigments reacted with an anti-bovine rhodopsin antibody (Rh29), which recognizes the short photoreceptor cells in lamprey retina. Unlike rhodopsins of higher vertebrates, the lamprey rhodopsin bleached gradually in the presence of 100 m M hydroxylamine even in the dark. Our results suggest that, despite its high similarities with other vertebrate rhodopsins, lamprey rhodopsin has a character different from those of higher vertebrates.