title: Mitogen-activated protein kinase phosphatase-1 (MKP-1): >100-fold nocturnal and norepinephrine-induced changes in the rat pineal gland.
abstract: The norepinephrine-driven increase in mitogen-activated protein kinase (MAPK) activity is part of the mechanism that regulates arylalkylamine N-acetyltransferase (AA-NAT) activity in the rat pineal gland. We now report a marked nocturnal increase in the expression of a MAPK phosphatase, MAP kinase phosphatase-1 (MKP-1), that was blocked by maintaining animals in constant light or treatment with propranolol. MKP-1 expression was regulated by norepinephrine acting through both alpha- and beta-adrenergic receptors. These results establish a nocturnal increase in pineal MKP-1 expression that is under the control of a photoneural system. Because substrates of MKP-1 can influence AA-NAT activity, our findings suggest the involvement of MKP-1 in the regulation of the nocturnal AA-NAT signal.
authors.affiliation: Department of Physiology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alta., Canada T6G 2H7.
authors.forename: Donald M
authors.initials: DM
authors.lastname: Price
authors.forename: Constance L
authors.initials: CL
authors.lastname: Chik
authors.forename: David
authors.initials: D
authors.lastname: Terriff
authors.forename: Joan
authors.initials: J
authors.lastname: Weller
authors.forename: Ann
authors.initials: A
authors.lastname: Humphries
authors.forename: David A
authors.initials: DA
authors.lastname: Carter
authors.forename: David C
authors.initials: DC
authors.lastname: Klein
authors.forename: Anthony K
authors.initials: AK
authors.lastname: Ho
mesh_terms: D000123:Acetyltransferases / Q000378:metabolism; D000818:Animals; D001483:Base Sequence; D018797:Cell Cycle Proteins / Q000378:metabolism*; D017931:DNA Primers; D003624:Darkness; D054638:Dual Specificity Phosphatase 1; D017874:Immediate-Early Proteins / Q000378:metabolism*; D008027:Light; D008550:Melatonin / Q000096:biosynthesis; D009638:Norepinephrine / Q000502:physiology*; D010749:Phosphoprotein Phosphatases / Q000378:metabolism*; D010870:Pineal Gland / Q000201:enzymology / Q000378:metabolism* / Q000502:physiology; D054645:Protein Phosphatase 1; D017027:Protein Tyrosine Phosphatases / Q000378:metabolism*; D051381:Rats; D011942:Receptors, Adrenergic, alpha / Q000502:physiology; D011943:Receptors, Adrenergic, beta / Q000502:physiology
chemical_list: D018797:Cell Cycle Proteins; D017931:DNA Primers; D017874:Immediate-Early Proteins; D011942:Receptors, Adrenergic, alpha; D011943:Receptors, Adrenergic, beta; D000123:Acetyltransferases; D010749:Phosphoprotein Phosphatases; D054645:Protein Phosphatase 1; D054638:Dual Specificity Phosphatase 1; C517021:Dusp1 protein, rat; D017027:Protein Tyrosine Phosphatases; D008550:Melatonin; D009638:Norepinephrine