title: cAMP-dependent protein kinase induces cAMP-response element-binding protein phosphorylation via an intracellular calcium release/ERK-dependent pathway in striatal neurons.
abstract: Activation of the cAMP-dependent protein kinase A (PKA) pathway may induce cAMP-response element-binding protein (CREB) phosphorylation either directly or via cross-talk mechanisms with other signal transduction pathways. In this study, we have investigated in striatal primary cultures the mechanism by which activation of the cAMP/PKA-dependent pathway leads to CREB phosphorylation via the extracellular signal-regulated kinase (ERK)-dependent pathway. We have found that PKA-induced CREB phosphorylation and CREB-dependent transcription are mediated by calcium (Ca(2+)) release from intracellular stores and are blocked by inhibitors of the protein kinase C and ERK pathways. This mechanism appears to be mediated by the small G-protein Rap1, whose activation appears to be primed by PKA-induced Ca(2+) release but not further induced by direct or indirect PKA- or protein kinase C-dependent phosphorylation. These results suggest that, in striatal neurons, intracellular Ca(2+) release, Rap1, and ERK pathway play a crucial role in the PKA-induced CREB phosphorylation and CREB-dependent transcription.
authors.affiliation: Dipartimento di Farmacologia Sperimentale ed Applicata, Facoltà di Farmacia, Università di Pavia, Pavia 27100, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Zanassi
authors.forename: M
authors.initials: M
authors.lastname: Paolillo
authors.forename: A
authors.initials: A
authors.lastname: Feliciello
authors.forename: E V
authors.initials: EV
authors.lastname: Avvedimento
authors.forename: V
authors.initials: V
authors.lastname: Gallo
authors.forename: S
authors.initials: S
authors.lastname: Schinelli
mesh_terms: D000818:Animals; D050882:CREB-Binding Protein; D002118:Calcium / Q000378:metabolism*; D003342:Corpus Striatum / Q000166:cytology / Q000378:metabolism*; D000242:Cyclic AMP / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism*; D004789:Enzyme Activation; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism*; D009687:Nuclear Proteins / Q000378:metabolism*; D010766:Phosphorylation; D051381:Rats; D017207:Rats, Sprague-Dawley; D015534:Trans-Activators / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D009687:Nuclear Proteins; D015534:Trans-Activators; D000242:Cyclic AMP; D050882:CREB-Binding Protein; C494365:Crebbp protein, rat; D017868:Cyclic AMP-Dependent Protein Kinases; D020928:Mitogen-Activated Protein Kinases; D002118:Calcium