Rapid activation of hippocampal casein kinase II during long-term potentiation.
Several studies suggest that protein kinase C and type II Ca2+/calmodulin-dependent protein kinase are activated during induction of long-term potentiation (LTP). We now report that casein kinase II (CK-II), which is present in high concentration in the hippocampus, is also activated in the CA1 region during LTP. CK-II activity increased within 2 min after a train of high-frequency electrical stimulations and reached a maximum (2-fold increase) 5 min later before returning to baseline value. The stimulated protein kinase activity, which was blocked by a selective antagonist of N-methyl-D-aspartate receptors, exhibited specific properties of CK-II, including phosphorylation of the specific substrates of CK-II, marked inhibition by a low heparin concentration, and the use of GTP as a phosphate donor. CK-II activity was also selectively and rapidly augmented in another form of LTP produced by bath application of tetraethylammonium; this LTP (called LTPk) is Ca2+ dependent but N-methyl-D-aspartate independent. Phosphorylation of casein that was not inhibited by heparin (i.e., casein kinase I) remained unchanged. We suggest that an increase in CK-II activity is important in LTP induction.
Charriaut-Marlangue
C
C
Laboratoire de Neurobiologie et Physiopathologie du Développement, Institut National de la Santé et de la Recherche Médicale U 29, Paris, France.
Otani
S
S
Creuzet
C
C
Ben-Ari
Y
Y
Loeb
J
J
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D047388:Casein Kinases; D003600:Cytosol / Q000201:enzymology; D004558:Electric Stimulation; D004789:Enzyme Activation; D006160:Guanosine Triphosphate / Q000378:metabolism; D006624:Hippocampus / Q000201:enzymology / Q000502:physiology*; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D011494:Protein Kinases / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013379:Substrate Specificity; D013997:Time Factors
D006160:Guanosine Triphosphate; D000255:Adenosine Triphosphate; D011494:Protein Kinases; D047388:Casein Kinases