title: Evidence for a dissociable protein subunit required for calmodulin stimulation of brain adenylate cyclase.
abstract: An adenylate cyclase [ATP pyrophosphatelyase (cyclizing), EC 4.6.1.1] preparation that is not stimulated by NaF,5'-guanylyl imidodiphosphate, or Ca2+.calmodulin has been isolated from bovine cerebral cortex by Affi-Gel Blue chromatography and calmodulin-Sepharose chromatography. Sensitivity to these effectors was restored by incubation of the adenylate cyclase preparation with detergent-solubilized protein from bovine cerebral cortex. Reconstitution of of Ca2+.calmodulin activation required the presence of 5'-guanylyl imidodiphosphate. The factor required for restoration of Ca2+.calmodulin stimulation was sensitive to heat, trypsin digestion, and N-ethylmaleimide. These observations suggest that this adenylate cyclase activity requires the presence of one or more guanyl nucleotide binding subunits for calmodulin sensitivity.
mesh_terms: D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D002135:Calcium-Binding Proteins / Q000494:pharmacology*; D002147:Calmodulin / Q000494:pharmacology*; D002417:Cattle; D002540:Cerebral Cortex / Q000201:enzymology*; D004789:Enzyme Activation / Q000187:drug effects; D005033:Ethylmaleimide / Q000494:pharmacology; D005459:Fluorides / Q000494:pharmacology; D006165:Guanylyl Imidodiphosphate / Q000494:pharmacology; D046911:Macromolecular Substances; D013329:Structure-Activity Relationship; D013696:Temperature; D014357:Trypsin / Q000378:metabolism
chemical_list: D002135:Calcium-Binding Proteins; D002147:Calmodulin; D046911:Macromolecular Substances; D006165:Guanylyl Imidodiphosphate; D014357:Trypsin; D000262:Adenylyl Cyclases; D005033:Ethylmaleimide; D005459:Fluorides