M-phase-specific cdc2 protein kinase phosphorylates the beta subunit of casein kinase II and increases casein kinase II activity.
The M-phase-specific cdc2 (cell division control) protein kinase (a component of the M-phase-promoting factor) was found to activate casein kinase II in vitro. The increase in casein kinase II activity ranged over 1.5-5-fold. Increase in activity was prevented if ATP was replaced during the activation reaction by a non-hydrolysable analogue. Alkaline phosphatase treatment of the activated enzyme decreased the activity to the basal level. The beta subunit of casein kinase II was phosphorylated by cdc2 protein kinase at site(s) different from the autophosphorylation sites of the enzyme. Phosphoamino acid analysis showed that the beta subunit was phosphorylated by cdc2 protein kinase at threonine residues while autophosphorylation involved serine residues. Casein kinase II may be part of the cascade which leads to increased phosphorylation of many proteins at M-phase and therefore be involved in the pleiotropic effects of M-phase-promoting factor.
Mulner-Lorillon
O
O
Laboratoire de Physiologie de la Reproduction, Institut National de la Recherche Agronomique, Université Pierre et Marie Curie, Paris, France.
Cormier
P
P
Labbé
J C
JC
Dorée
M
M
Poulhe
R
R
Osborne
H
H
Bellé
R
R
D000255:Adenosine Triphosphate / Q000378:metabolism; D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D001345:Autoradiography; D016203:CDC2 Protein Kinase / Q000378:metabolism*; D047388:Casein Kinases; D002453:Cell Cycle; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation; D005260:Female; D066298:In Vitro Techniques; D007700:Kinetics; D016200:Maturation-Promoting Factor / Q000378:metabolism; D008938:Mitosis; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism*; D013215:Starfish; D014982:Xenopus laevis
D000255:Adenosine Triphosphate; D011494:Protein Kinases; D047388:Casein Kinases; D016203:CDC2 Protein Kinase; D016200:Maturation-Promoting Factor; D000469:Alkaline Phosphatase