title: Activation of mitogen-activated protein (MAP) kinase by a MAP kinase-kinase.
abstract: Previously it has been shown that acute 12-O-tetradecanoylphorbol-13-acetate treatment of intact U937 cells results in activation of mitogen-activated protein (MAP) kinase and a MAP kinase activator. MAP kinase activator induces phosphorylation of MAP kinase on tyrosine and threonine residues, thereby activating MAP kinase. Here, experiments with the irreversible kinase inhibitor, 5'-p-fluorosulfonylbenzoyladenosine (FSBA), show that MAP kinase activator is in fact a MAP kinase-kinase. Treatment of MAP kinase activator with FSBA results in complete inactivation. This inactivation is prevented by a 10-fold excess of ATP. Inactivation of MAP kinase by FSBA does not affect the extent of threonine/tyrosine phosphorylation induced by MAP kinase-kinase.
authors.affiliation: Imperial Cancer Research Fund, London, United Kingdom.
authors.forename: P D
authors.initials: PD
authors.lastname: Adams
authors.forename: P J
authors.initials: PJ
authors.lastname: Parker
mesh_terms: D000241:Adenosine / Q000031:analogs & derivatives / Q000737:chemistry; D001345:Autoradiography; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D002460:Cell Line; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation; D010766:Phosphorylation; D047428:Protein Kinase Inhibitors; D011494:Protein Kinases / Q000378:metabolism*; D013379:Substrate Specificity; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013912:Threonine / Q000378:metabolism; D014443:Tyrosine / Q000378:metabolism
chemical_list: D047428:Protein Kinase Inhibitors; D013912:Threonine; D014443:Tyrosine; C010959:5'-(4-fluorosulfonylbenzoyl)adenosine; D011494:Protein Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D000241:Adenosine; D013755:Tetradecanoylphorbol Acetate