title: Evidence for ATP-ase activity of arrestin from bovine photoreceptors.
abstract: In vertebrate photoreceptors the soluble protein arrestin (45 kDa) is involved in controlling the light dependent activity of receptor proteins such as transducin or the cGMP-phosphodiesterase. Arrestin has further been identified as the retinal-S-antigen which is assumed to cause the autoimmune disease uveitis. In a first communication a binding of the nucleotide ATP to arrestin was described. In this subsequent study it is shown that arrestin is also able to hydrolyse ATP at a rate of (5.1 +/- 0.3) x 10(-3) U/mg.min with C1/2 = 93 +/- 5 nM and a Hill coefficient n = 1.8 +/- 0.1 at pH 7.2 and 20 degrees C. These findings suggest a new insight into the process of regulating photoreceptor activity.
authors.affiliation: Max-Volmer-Institute, Technical University Berlin, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Glitscher
authors.forename: H
authors.initials: H
authors.lastname: Rüppel
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism; D000494:Allosteric Regulation; D000818:Animals; D000941:Antigens / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D019393:Arrestin; D002417:Cattle; D005136:Eye Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D066298:In Vitro Techniques; D007700:Kinetics; D008970:Molecular Weight; D010786:Photoreceptor Cells / Q000201:enzymology*; D015398:Signal Transduction
chemical_list: D000941:Antigens; D019393:Arrestin; D005136:Eye Proteins; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases