Regulation of cyclic AMP-dependent response element-binding protein (CREB) by the nociceptin/orphanin FQ in human dopaminergic SH-SY5Y cells.
Nociceptin/orphanin FQ (N/OFQ), an endogenous ligand for opioid receptor-like (ORL1) receptor, transduces signaling cascades implicated in MAPK, PKC, PLC, and calcium, etc. This study was designed to investigate the intracellular signaling mechanism of N/OFQ in human dopaminergic neuroblastoma SH-SY5Y cells. N/OFQ rapidly induced the phosphorylation of CREB, which was significantly suppressed by pretreatment of PKA inhibitor, but not by MAPK inhibitors. It also time-dependently increased the phosphorylation of MAPK, which was proven as ERKs, whereas it did not affect the PI3K activity. Interestingly, KT5720, a specific inhibitor of PKA, markedly suppressed the phosphorylation of MAPK by N/OFQ in SH-SY5Y cells. Furthermore, BAPTA-AM, an intracellular chelator of Ca(2+), completely abolished the phosphorylation of CREB as well as MAPK in N/OFQ-treated SH-SY5Y cells. Taken together, these results suggest that N/OFQ independently induces the activation of CREB prior to MAPK phosphorylation, which was also modulated by PKA. Furthermore, Ca(2+)-related signaling implicates in the phosphorylation processes of CREB and MAPK simultaneously.
Kim
Myung-Sunny
MS
Institute of Medical Science, Wonkwang University School of Medicine, Iksan Chonbuk, 570-749, South Korea.
Cheong
Young-Pyo
YP
So
Hong-Seob
HS
Lee
Kang-Min
KM
Son
Yong
Y
Lee
Chang-Soo
CS
Yun
Jae-Seung
JS
Park
Raekil
R
D002118:Calcium / Q000502:physiology; D002460:Cell Line; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000037:antagonists & inhibitors; D004298:Dopamine / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D007700:Kinetics; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D009447:Neuroblastoma; D018847:Opioid Peptides / Q000494:pharmacology*; D010766:Phosphorylation; D047428:Protein Kinase Inhibitors; D000097629:Nociceptin
D002118:Calcium; D017362:Cyclic AMP Response Element-Binding Protein; D017868:Cyclic AMP-Dependent Protein Kinases; D004298:Dopamine; D004791:Enzyme Inhibitors; D020928:Mitogen-Activated Protein Kinases; D018847:Opioid Peptides; D047428:Protein Kinase Inhibitors; D000097629:Nociceptin