TY - JOUR
T1 - Involvement of calcium-calmodulin protein kinase but not mitogen-activated protein kinase in light-induced phase delays and Per gene expression in the suprachiasmatic nucleus of the hamster
AU - Yokota, Shin Ichi
AU - Yamamoto, Masakazu
AU - Moriya, Takahiro
AU - Akiyama, Masashi
AU - Fukunaga, Kohji
AU - Miyamoto, Eishichi
AU - Shibata, Shigenobu
PY - 2001/4/25
Y1 - 2001/4/25
N2 - It is known that Ca2+-dependent phosphorylation of cAMP response element binding protein (CREB) and the rapid induction of mPer1 and mPer2, mouse period genes in the suprachiasmatic nucleus (SCN) are associated with light-induced phase shifting. The CREB/CRE transcriptional pathway has been shown to be activated by calcium/calmodulin dependent kinase II (CaMKII) and mitogen-activated protein kinase (MAPK); however, there is a lack of evidence concerning whether the activation of CaMKII and/or MAPK elicited by photic stimuli are associated with the change in Per gene expression and behavioral phase shifting. In this experiment, we found there was an inhibitory effect by KN93, CaMKII inhibitor, on hamster Per1 and Per2 expression in the SCN and on phase delays in wheel running rhythm induced by light pulses. PD98059 and U0126, MAPK kinase inhibitors, however, affected neither light-induced Per1 and Per2 expression nor behavioral phase delays, even though PD98059 attenuated the light-induced phosphorylation of MAPK in the SCN. The present findings demonstrate that the light-induced activation of CaMKII plays an important role in the induction of Per1 and Per2 mRNA in the hamster SCN as well as phase shifting. These results suggest that gated induction of Per1 and/or Per2 genes through CaMKII-CREB/CRE accompanied with photic stimuli may be a critical step in phase shifting.
AB - It is known that Ca2+-dependent phosphorylation of cAMP response element binding protein (CREB) and the rapid induction of mPer1 and mPer2, mouse period genes in the suprachiasmatic nucleus (SCN) are associated with light-induced phase shifting. The CREB/CRE transcriptional pathway has been shown to be activated by calcium/calmodulin dependent kinase II (CaMKII) and mitogen-activated protein kinase (MAPK); however, there is a lack of evidence concerning whether the activation of CaMKII and/or MAPK elicited by photic stimuli are associated with the change in Per gene expression and behavioral phase shifting. In this experiment, we found there was an inhibitory effect by KN93, CaMKII inhibitor, on hamster Per1 and Per2 expression in the SCN and on phase delays in wheel running rhythm induced by light pulses. PD98059 and U0126, MAPK kinase inhibitors, however, affected neither light-induced Per1 and Per2 expression nor behavioral phase delays, even though PD98059 attenuated the light-induced phosphorylation of MAPK in the SCN. The present findings demonstrate that the light-induced activation of CaMKII plays an important role in the induction of Per1 and Per2 mRNA in the hamster SCN as well as phase shifting. These results suggest that gated induction of Per1 and/or Per2 genes through CaMKII-CREB/CRE accompanied with photic stimuli may be a critical step in phase shifting.
KW - Calcium/calmodulin dependent kinase
KW - Circadian rhythm
KW - Hamster
KW - Mitogen-activated protein kinase
KW - Per genes
KW - Suprachiasmatic nucleus
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U2 - 10.1046/j.1471-4159.2001.00270.x
DO - 10.1046/j.1471-4159.2001.00270.x
M3 - Article
C2 - 11299324
AN - SCOPUS:0035052493
VL - 77
SP - 618
EP - 627
JO - Journal of Neurochemistry
JF - Journal of Neurochemistry
SN - 0022-3042
IS - 2
ER -