title: Calmodulin-dependent protein kinase (kinase II) which is involved in the activation of tryptophan 5-monooxygenase catalyzes phosphorylation of tubulin.
abstract: Tubulin was shown to be an endogenous substrate of the calmodulin-dependent protein kinase (kinase II), which is involved in the activation of tryptophan 5-monooxygenase [T. Yamauchi and H. Fujisawa (1983) Eur. J. Biochem. 132, 15-21]. Serine and threonine were identified as the phosphate acceptor amino acids of tubulin. The Vmax of the phosphorylation of tubulin and the apparent Km value for tubulin of calmodulin-dependent protein kinase II were 89 nmol phosphate transferred min-1 mg kinase II-1 and 1.7 microM, respectively. The maximum 32P incorporation into tubulin was 0.18 mol Pi/mol alpha-tubulin and 0.13 mol Pi/mol beta-tubulin. The phosphorylation of tubulin was decreased by the denaturation of tubulin. The phosphorylation of tubulin by kinase II did not affect the assembly of microtubules.
mesh_terms: D000818:Animals; D002147:Calmodulin / Q000502:physiology*; D002384:Catalysis; D002499:Centrifugation, Density Gradient; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010766:Phosphorylation; D011489:Protein Denaturation; D011494:Protein Kinases / Q000378:metabolism*; D051381:Rats; D014365:Tryptophan Hydroxylase / Q000378:metabolism*; D014404:Tubulin / Q000378:metabolism*
chemical_list: D002147:Calmodulin; D014404:Tubulin; D014365:Tryptophan Hydroxylase; D011494:Protein Kinases