title: Structure and function of gamma-subunit of photoreceptor G-protein (transducin).
abstract: 1. The gamma-subunit of the vertebrate photoreceptor GTP-binding protein (transducin) is S-farnesylated at the C-terminal cysteine residue, with a part of the residue being methyl-esterified at the alpha-carboxyl group. 2. Functionally, the modified cysteine residue is implicated in efficient coupling of the alpha- and beta gamma-subunits, and indispensible for expressing GTP-binding activity. 3. Similar modifications, isoprenylation and methyl-esterification of the C-terminal cysteine residue have been found in a variety of proteins involved in signal transduction and growth regulation processes. However, it seems likely that the physiological roles of the modifications are different for the various proteins.
authors.affiliation: Department of Ophthalmology, Sapporo Medical College, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Ohguro
authors.forename: Y
authors.initials: Y
authors.lastname: Fukada
authors.forename: T
authors.initials: T
authors.lastname: Akino
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D006801:Humans; D008969:Molecular Sequence Data; D015293:Transducin / Q000737:chemistry / Q000502:physiology*
chemical_list: D015293:Transducin