title: Retinylidene proteins: structures and functions from archaea to humans.
abstract: Retinylidene proteins, containing seven membrane-embedded alpha-helices that form an internal pocket in which the chromophore retinal is bound, are ubiquitous in photoreceptor cells in eyes throughout the animal kingdom. They are also present in a diverse range of other organisms and locations, such as archaeal prokaryotes, unicellular eukaryotic microbes, the dermal tissue of frogs, the pineal glands of lizards and birds, the hypothalamus of toads, and the human brain. Their functions include light-driven ion transport and phototaxis signaling in microorganisms, and retinal isomerization and various types of photosignal transduction in higher animals. The aims of this review are to examine this group of photoactive proteins as a whole, to summarize our current understanding of structure/function relationships in the best-studied examples, and to report recent new developments.
authors.affiliation: Department of Microbiology and Molecular Genetics, University of Texas Medical School, Houston, Texas 77030, USA. spudich@utmmg.med.uth.tmc.edu
authors.forename: J L
authors.initials: JL
authors.lastname: Spudich
authors.forename: C S
authors.initials: CS
authors.lastname: Yang
authors.forename: K H
authors.initials: KH
authors.lastname: Jung
authors.forename: E N
authors.initials: EN
authors.lastname: Spudich
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001105:Archaea / Q000378:metabolism*; D019843:Archaeal Proteins / Q000737:chemistry / Q000502:physiology*; D005057:Eukaryotic Cells; D006801:Humans; D008969:Molecular Sequence Data; D012176:Retinoids / Q000737:chemistry; D012243:Rhodopsin / Q000737:chemistry / Q000502:physiology*; D013329:Structure-Activity Relationship
chemical_list: D019843:Archaeal Proteins; D012176:Retinoids; C121835:retinylidene chromophore; D012243:Rhodopsin