Characterization of a calmodulin-binding protein that is deficient in trifluoperazine-resistant variants of the macrophage-like cell line J774.
A calmodulin-binding protein is present in extracts of the macrophage-like mouse cell line J774 and in extracts of thioglycollate-stimulated mouse peritoneal macrophages; it is deficient in variants of J774 resistant to trifluoperazine and in resident peritoneal macrophages. The calmodulin-binding protein [CaMBP (J7)0.5] was purified from J774 and resolved from endogenous cyclic nucleotide phosphodiesterase and protein kinase activities. The protein has an apparent native Mr of 125,000-150,000 and binds calmodulin in a calcium-dependent manner with a Kd of 20 nM. It inhibits the ability of calmodulin to activate phosphodiesterase. Its sedimentation constant in glycerol gradients containing calmodulin was dependent upon the relative concentrations of calmodulin and the calmodulin-binding protein.
D000818:Animals; D002148:Calmodulin-Binding Proteins; D002352:Carrier Proteins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D002460:Cell Line; D004351:Drug Resistance; D014644:Genetic Variation; D007700:Kinetics; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D014268:Trifluoperazine / Q000494:pharmacology*
D002148:Calmodulin-Binding Proteins; D002352:Carrier Proteins; D014268:Trifluoperazine