title: Convergent effects of Ca(2+) and cAMP signals on the expression of immediate early genes in neurons.
abstract: How the expression of immediate early genes (IEGs) is controlled in response to neurotransmissions is unknown. Using cultured rat cortical cells, we investigated the expression of IEGs regulated by Ca(2+) and/or cAMP signals. The expression of c-fos was transiently induced by treatment of cells with high potassium (high K(+)), which evoked depolarization, or forskolin, an adenylate cyclase activator. c-fos expression was persistently and synergistically induced by simultaneous treatment with high K(+) and forskolin via cAMP-response element (CRE). Microarray analysis indicated the expression profiles of IEGs caused by depolarization in the presence or absence of forskolin. When a novel index was included to investigate the profile of IEGs, we found that high K(+)-induced expression of IEGs was stimulatory or negatively changed in the presence of forskolin, suggesting distinct convergent effects of Ca(2+) and cAMP signals on the expression of IEGs.
authors.affiliation: Department of Biological Chemistry, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan. Electronic address: mamofuku@pha.u-toyama.ac.jp.
authors.forename: Mamoru
authors.initials: M
authors.lastname: Fukuchi
authors.affiliation: Department of Biological Chemistry, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan.
authors.forename: Kazufumi
authors.initials: K
authors.lastname: Kanesaki
authors.affiliation: Division of Molecular Genetics Research, Life Science Research Center, University of Toyama, Toyama, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Takasaki
authors.affiliation: Department of Biological Chemistry, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Tabuchi
authors.affiliation: Department of Biological Chemistry, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan. Electronic address: tsuda@pha.u-toyama.ac.jp.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Tsuda
mesh_terms: D000818:Animals; D020013:Calcium Signaling; D002478:Cells, Cultured; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism*; D015870:Gene Expression / Q000187:drug effects; D017781:Genes, Immediate-Early / Q000187:drug effects; D016762:Genes, fos / Q000187:drug effects; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D020218:Response Elements
chemical_list: D005576:Colforsin; D000242:Cyclic AMP; D011188:Potassium
keywords: CRE; Ca(2+); IEG; Microarray; cAMP