title: Pineal opsin: a nonvisual opsin expressed in chick pineal.
abstract: Pineal opsin (P-opsin), an opsin from chick that is highly expressed in pineal but is not detectable in retina, was cloned by the polymerase chain reaction. It is likely that the P-opsin lineage diverged from the retinal opsins early in opsin evolution. The amino acid sequence of P-opsin is 42 to 46 percent identical to that of the retinal opsins. P-opsin is a seven-membrane spanning, G protein-linked receptor with a Schiff-base lysine in the seventh membrane span and a Schiff-base counterion in the third membrane span. The primary sequence of P-opsin suggests that it will be maximally sensitive to approximately 500-nanometer light and produce a slow and prolonged phototransduction response consistent with the nonvisual function of pineal photoreception.
authors.affiliation: Roche Institute of Molecular Biology, Roche Research Center, Nutley, NJ 07110.
authors.forename: M
authors.initials: M
authors.lastname: Max
authors.forename: P J
authors.initials: PJ
authors.lastname: McKinnon
authors.forename: K J
authors.initials: KJ
authors.lastname: Seidenman
authors.forename: R K
authors.initials: RK
authors.lastname: Barrett
authors.forename: M L
authors.initials: ML
authors.lastname: Applebury
authors.forename: J S
authors.initials: JS
authors.lastname: Takahashi
authors.forename: R F
authors.initials: RF
authors.lastname: Margolskee
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D030161:Avian Proteins; D001483:Base Sequence; D005075:Biological Evolution; D001923:Brain Chemistry; D002645:Chickens; D003001:Cloning, Molecular; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000032:analysis / Q000737:chemistry* / Q000235:genetics / Q000502:physiology; D010870:Pineal Gland / Q000737:chemistry*; D017433:Protein Structure, Secondary; D012333:RNA, Messenger / Q000032:analysis; D012160:Retina / Q000737:chemistry; D017299:Rod Opsins / Q000032:analysis / Q000737:chemistry* / Q000235:genetics / Q000502:physiology; D017386:Sequence Homology, Amino Acid
chemical_list: D030161:Avian Proteins; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D017299:Rod Opsins; C090139:OPNP protein, chicken