title: Identification of a single phosphorylation site within octopus rhodopsin.
abstract: Light-dependent phosphorylation of rhodopsin (Rho) is a first step in the desensitization of the signaling state of the receptor during vertebrate and invertebrate visual transduction. We found that only 358Ser of the photoactivated octopus Rho (oRho*) was phosphorylated by octopus rhodopsin kinase (oRK). Tryptic truncation of the C-terminal PPQGY repeats of oRho that follow the phosphorylation region did not influence spectral or G-protein activation properties of oRho but abolished phosphorylation. Despite significant structural differences between oRK and mammalian RK, these results provide further evidence of the importance of singly phosphorylated species of Rho* in the generation of arrestin binding sites.
authors.affiliation: Department of Ophthalmology, Sapporo Medical University School of Medicine, Japan. ooguro@sapmed.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Ohguro
authors.forename: N
authors.initials: N
authors.lastname: Yoshida
authors.forename: H
authors.initials: H
authors.lastname: Shindou
authors.forename: J W
authors.initials: JW
authors.lastname: Crabb
authors.forename: K
authors.initials: K
authors.lastname: Palczewski
authors.forename: M
authors.initials: M
authors.lastname: Tsuda
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D002417:Cattle; D005136:Eye Proteins; D051606:G-Protein-Coupled Receptor Kinase 1; D008871:Microvilli / Q000201:enzymology; D008969:Molecular Sequence Data; D049831:Octopodiformes; D010766:Phosphorylation; D017956:Photoreceptor Cells, Invertebrate / Q000737:chemistry / Q000378:metabolism*; D011494:Protein Kinases / Q000737:chemistry / Q000378:metabolism*; D017433:Protein Structure, Secondary; D012243:Rhodopsin / Q000378:metabolism*; D014785:Vision, Ocular
chemical_list: D005136:Eye Proteins; D012243:Rhodopsin; D011494:Protein Kinases; D051606:G-Protein-Coupled Receptor Kinase 1