title: A photoaffinity probe for the cardiac adenosine transporter.
abstract: We have developed and utilized a photoaffinity probe to identify the adenosine transporter in cardiac sarcolemmal (SL) vesicles. The probe is an azidosalicylate derivative of adenosine made by reacting adenosine with N-hydroxysuccinimidyl-4-azidosalicylic acid (NHS-ASA). Following synthesis and radiolabeling of the probe (ASA-adenosine), 125I-ASA-adenosine was purified by high pressure liquid chromatography. Iodine-125-ASA-adenosine, upon irradiation with uv light, covalently labeled a 65 kDa protein in bovine cardiac SL vesicles. Labeling of this protein was greatly diminished in the presence of nonradiolabeled adenosine, 5'-amino adenosine, or guanosine (inhibitors of purine nucleoside transport) but not by glucose (which does not inhibit transport). We conclude that the cardiac adenosine transporter is a protein with an apparent Mr of 65 kDa.
authors.forename: C C
authors.initials: CC
authors.lastname: Hale
authors.forename: M J
authors.initials: MJ
authors.lastname: Rovetto
mesh_terms: D000241:Adenosine / Q000737:chemistry / Q000378:metabolism*; D000345:Affinity Labels; D000818:Animals; D001386:Azides / Q000737:chemistry; D002352:Carrier Proteins / Q000032:analysis* / Q000378:metabolism; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D009206:Myocardium / Q000737:chemistry*; D012459:Salicylates / Q000737:chemistry; D013868:Thioinosine / Q000031:analogs & derivatives / Q000494:pharmacology
chemical_list: D000345:Affinity Labels; D001386:Azides; D002352:Carrier Proteins; D012459:Salicylates; D013868:Thioinosine; C063873:4-azidosalicylic acid; C001789:4-nitrobenzylthioinosine; D000241:Adenosine