title: Guanosine 3',5'-cyclic nucleotide binding proteins of bovine retina identified by photoaffinity labeling.
abstract: Cyclic GMP-binding proteins present in membrane fractions of bovine retina and, in particular, rod outer segments (ROS) were identified by photoaffinity labeling with 8-azido-[32P]cGMP. Two soluble proteins and two membrane-associated proteins were specifically labeled. The soluble proteins, 93 and 72 kDa, corresponded respectively to the alpha subunit of ROS cGMP phosphodiesterase and cGMP-dependent protein kinase. One of the two membrane-associated proteins, 53 kDa, was present in all particulate retinal fractions. Its function is unknown. It is distinct from cAMP-dependent protein kinase or the 63-kDa cGMP-activated channel from ROS. The second membrane-associated protein, 37 kDa, was present only in fractions that did not contain ROS. The molecular mass of this protein was similar to that of a cGMP-binding protein previously attributed to rod cells.
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology, Cambridge 02139.
authors.forename: D A
authors.initials: DA
authors.lastname: Thompson
authors.forename: H G
authors.initials: HG
authors.lastname: Khorana
mesh_terms: D000345:Affinity Labels / Q000378:metabolism*; D000818:Animals; D001386:Azides / Q000378:metabolism*; D002352:Carrier Proteins / Q000302:isolation & purification / Q000378:metabolism*; D002417:Cattle; D002846:Chromatography, Affinity; D002918:Chymotrypsin; D006152:Cyclic GMP / Q000031:analogs & derivatives* / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D047908:Intracellular Signaling Peptides and Proteins; D046911:Macromolecular Substances; D008970:Molecular Weight; D010449:Peptide Mapping; D010786:Photoreceptor Cells / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000378:metabolism; D012160:Retina / Q000378:metabolism*; D012374:Rod Cell Outer Segment / Q000378:metabolism*
chemical_list: D000345:Affinity Labels; D001386:Azides; D002352:Carrier Proteins; D047908:Intracellular Signaling Peptides and Proteins; D046911:Macromolecular Substances; D011956:Receptors, Cell Surface; C022994:cyclic GMP-binding protein; C063422:8-azidoguanosine cyclic monophosphate; D002918:Chymotrypsin; D006152:Cyclic GMP