title: The extracellular-signal-regulated protein kinases (Erks) are required for UV-induced AP-1 activation in JB6 cells.
abstract: Mitogen activated protein (MAP) kinase belongs to a large family of serine/threonine protein kinases, including extracellular-signal-regulated protein kinases (Erks), P38 kinase and c-Jun N-terminal kinases (JNKs). Although previous work has shown that both Erks and JNKs are activated in cells in response to ultraviolet (UV) irradiation, most studies have focused only on the role of JNKs in UV-induced AP-1 activation. Hence, the role of Erks in UV-induced AP-1 activity is not well defined. We here have investigated this issue by using MAP kinase kinase (MEK1) inhibitor PD098059 and a dominant negative Erk2, as well as wild-type Erk2, in a JB6 cell model. PD098059 inhibited UVB- or UVC-induced AP-1 activity and phosphorylation of MEK1 and Erks, but not JNKs, in JB6 Cl 41 cells. Overexpression of wild-type Erk2 in Cl 30.7b cells that contain small amounts of Erks caused a 46.6- or 138.1-fold increase of AP-1 activity by UVB and UVC, respectively; introduction of a dominant negative Erk2 into Cl 41 cells significantly blocked the UV-induced Erks activation as well as the AP-1 activation. In contrast, overexpression of wild-type Erk2 in Cl 30.7b cells and dominant negative Erk2 in Cl 41 cells did not show a marked influence on the phosphorylation of JNKs. These results demonstrate that activation of Erks, in addition to the previously reported JNKs, is required for UV-induced AP-1 activation.
authors.affiliation: The Hormel Institute, University of Minnesota, Austin 55912, USA.
authors.forename: C
authors.initials: C
authors.lastname: Huang
authors.forename: W Y
authors.initials: WY
authors.lastname: Ma
authors.forename: Z
authors.initials: Z
authors.lastname: Dong
mesh_terms: D000818:Animals; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000037:antagonists & inhibitors / Q000187:drug effects / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects; D002460:Cell Line; D004791:Enzyme Inhibitors / Q000494:pharmacology; D000078404:Epidermal Cells; D004817:Epidermis / Q000187:drug effects / Q000201:enzymology* / Q000528:radiation effects; D005419:Flavonoids / Q000494:pharmacology; D005799:Genes, Dominant; D048031:JNK Mitogen-Activated Protein Kinases; D048369:MAP Kinase Kinase 1; D051379:Mice; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020929:Mitogen-Activated Protein Kinase Kinases; D020928:Mitogen-Activated Protein Kinases; D010766:Phosphorylation / Q000187:drug effects; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D018808:Transcription Factor AP-1 / Q000378:metabolism* / Q000528:radiation effects*; D014466:Ultraviolet Rays
chemical_list: D004791:Enzyme Inhibitors; D005419:Flavonoids; D018808:Transcription Factor AP-1; D011505:Protein-Tyrosine Kinases; D017346:Protein Serine-Threonine Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048369:MAP Kinase Kinase 1; C482127:Map2k1 protein, mouse; D020929:Mitogen-Activated Protein Kinase Kinases; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one