Expression and subcellular localization of multifunctional calmodulin-dependent protein kinases-I, -II and -IV are altered in rat hippocampal CA1 neurons after induction of long-term potentiation.
Long-term potentiation (LTP) is considered to be associated with an increase in expression as well as activity of Ca(2+)/calmodulin-dependent protein kinases (CaMKs). LTP-induced and control hippocampal slices were studied by immunohistochemical and electronmicroscopic analyses using anti-CaMK-I, -II and -IV antibodies. All three kinases were demonstrated to increase their expression in CA1 neurons. CaMK-I was shown to mainly localize in the cytoplasm of the control and LTP-induced neurons, and a significant increase of immunoreactivity was observed in the latter neurons. A part of CaMK-I was found to translocate to the nuclei of LTP-induced hippocampal CA1 neurons. Direct evidence of the translocation of CaMK-II from cytoplasm to nuclei in LTP was demonstrated by immuno-electronmicroscopy. A significant increase in expression of CaMK-IV in the nuclei was also observed. Our data suggest that all the three CaMKs were actively involved in nuclear Ca(2+)-signaling in LTP.
Department of Physiology, Faculty of Medicine, Kagawa Medical University, 1750-1 Ikenobe, Miki-cho, 761-0793, Kagawa, Japan.
B Y
BY
Ahmed
F
F
Yamaguchi
T
T
Tsumura
T
T
Gotoh
K
K
Sugimoto
Y
Y
Tai
R
R
Konishi
R
R
Kobayashi
M
M
Tokuda
D000818:Animals; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism*; D005260:Female; D006624:Hippocampus / Q000166:cytology / Q000201:enzymology*; D066298:In Vitro Techniques; D017774:Long-Term Potentiation / Q000502:physiology*; D009474:Neurons / Q000166:cytology / Q000201:enzymology*; D051381:Rats; D017207:Rats, Sprague-Dawley
D017871:Calcium-Calmodulin-Dependent Protein Kinases