Regulation of cAMP-induced arylalkylamine N-acetyltransferase, Period1, and MKP-1 gene expression by mitogen-activated protein kinases in the rat pineal gland.
In rodent pineal glands, sympathetic innervation, which leads to norepinephrine release, is a key process in the circadian regulation of physiology and certain gene expressions. It has been shown that gene expression of the rate-limiting enzyme in the melatonin synthesis arylalkylamine N-acetyltransferase (Aa-Nat), circadian clock gene Period1, and mitogen-activated protein kinase (MAPK) phosphtase-1 (MKP-1), is controlled mainly by a norepinephrine-beta-adrenergic receptor-cAMP signaling cascade in the rat pineal gland. To further dissect the signaling cascades that regulate those gene expressions, we examined whether MAPKs are involved in cAMP-induced gene expression. Western blot and immunohistochemical analyses showed that one of the three MAPKs, c-Jun N-terminal kinase (JNK), was expressed in the pineal, and was phosphorylated by cAMP analogue stimulation with a peak 20 min after start of the stimulation, in vitro. A specific JNK inhibitor SP600125 (Anthra[1,9-cd]pyrazol-6(2H)-one1,9-pyrazoloanthrone), but not its negative control (N1-Methyl-1,9-pyrazoloanthrone), significantly reduced cAMP-stimulated Aa-Nat, Period1, and MKP-1 mRNA levels. Although another MAPK, p38(MAPK), has also been shown to be activated by cAMP stimulation, a p38(MAPK) inhibitor, SB203580 (4-(4-Fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)1H-imidazole, HCl), showed no effect on cAMP-induced Aa-Nat and Period1 mRNA levels; whereas SB203580, but not its negative analogue SB202474 (4-Ethyl-2(p-methoxyphenyl)-5-(4'-pyridyl)-IH-imidazole, DiHCl), significantly reduced cAMP-induced MKP-1 mRNA levels. Taken together, our data suggest that cAMP-induced Aa-Nat and Period1 are likely to be mediated by activation of JNK, whereas MKP-1 may be mediated by both p38(MAPK) and JNK activations.
Chansard
Mathieu
M
Department of Anatomy and Neurobiology, Center for Behavioral Neuroscience, Morehouse School of Medicine, 720 Westview Drive, SW, Atlanta, GA 30310-1495, USA.
Iwahana
Eiko
E
Liang
Jian
J
Fukuhara
Chiaki
C
D000704:Analysis of Variance; D000818:Animals; D000873:Anthracenes / Q000494:pharmacology; D001191:Arylamine N-Acetyltransferase / Q000235:genetics / Q000378:metabolism*; D015153:Blotting, Western / Q000379:methods; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D000242:Cyclic AMP / Q000494:pharmacology*; D004347:Drug Interactions; D054638:Dual Specificity Phosphatase 1; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005136:Eye Proteins / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects* / Q000502:physiology; D007093:Imidazoles / Q000494:pharmacology; D017874:Immediate-Early Proteins / Q000235:genetics / Q000378:metabolism*; D007150:Immunohistochemistry / Q000379:methods; D048670:MAP Kinase Kinase 4 / Q000378:metabolism; D008297:Male; D020928:Mitogen-Activated Protein Kinases / Q000494:pharmacology*; D008970:Molecular Weight; D009924:Organ Culture Techniques; D056950:Period Circadian Proteins; D010749:Phosphoprotein Phosphatases / Q000235:genetics / Q000378:metabolism*; D010870:Pineal Gland / Q000187:drug effects* / Q000378:metabolism; D054645:Protein Phosphatase 1; D017027:Protein Tyrosine Phosphatases / Q000235:genetics / Q000378:metabolism*; D011725:Pyridines / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D013997:Time Factors
D000873:Anthracenes; D018797:Cell Cycle Proteins; D004791:Enzyme Inhibitors; D005136:Eye Proteins; D007093:Imidazoles; D017874:Immediate-Early Proteins; C539024:Per1 protein, rat; D056950:Period Circadian Proteins; D011725:Pyridines; C432165:pyrazolanthrone; D000242:Cyclic AMP; D001191:Arylamine N-Acetyltransferase; D020928:Mitogen-Activated Protein Kinases; D048670:MAP Kinase Kinase 4; D010749:Phosphoprotein Phosphatases; D054645:Protein Phosphatase 1; D054638:Dual Specificity Phosphatase 1; C517021:Dusp1 protein, rat; D017027:Protein Tyrosine Phosphatases; C093642:SB 203580