title: Solar ultraviolet light activates extracellular signal-regulated kinases and the ternary complex factor in human normal keratinocytes.
abstract: Exposure to ultraviolet radiation of solar light is responsible for inflammation, premature skin aging and is the main cause of human skin carcinogenesis. While the noxious consequences of U.V. exposure are known, the molecular events triggered by this radiation are poorly understood. We observed that U.V.-A and U.V.-B irradiation of human keratinocytes induces the activation of tyrosine kinase pathways leading to the tyrosine phosphorylation of several cellular proteins. We also observed a stimulation of the Stress Activated Protein kinases (SAPKs), p38 and JNK, and an activation of the transcription factors AP-1 in response to U.V.-A and U.V.-B radiation. Furthermore, we clearly demonstrated that physiological U.V. doses are able to activate the Extracellular signal-Regulated Kinases, ERK1 and ERK2, which could explain the activation of the Ternary Complex Factor. Thus, in human keratinocytes, solar U.V. light activates multiple signalling pathways that could be involved in skin inflammation following U.V.-induced skin injury or in U.V.-induced skin carcinogenesis.
authors.affiliation: Institut National de la Santé et de la Recherche Médicale (INSERM) U 385, Faculté de médecine, Nice, France.
authors.forename: W
authors.initials: W
authors.lastname: Englaro
authors.forename: B
authors.initials: B
authors.lastname: Dérijard
authors.forename: J P
authors.initials: JP
authors.lastname: Ortonne
authors.forename: R
authors.initials: R
authors.lastname: Ballotti
mesh_terms: D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism* / Q000528:radiation effects*; D004789:Enzyme Activation / Q000528:radiation effects; D005110:Extracellular Space / Q000201:enzymology; D006801:Humans; D015603:Keratinocytes / Q000201:enzymology* / Q000528:radiation effects*; D010766:Phosphorylation; D015398:Signal Transduction / Q000502:physiology / Q000528:radiation effects; D013472:Sunlight; D018808:Transcription Factor AP-1 / Q000528:radiation effects; D014157:Transcription Factors / Q000378:metabolism* / Q000528:radiation effects*; D014466:Ultraviolet Rays
chemical_list: D018808:Transcription Factor AP-1; D014157:Transcription Factors; D017871:Calcium-Calmodulin-Dependent Protein Kinases