title: Induction of the IL-13 receptor alpha2-chain by IL-4 and IL-13 in human keratinocytes: involvement of STAT6, ERK and p38 MAPK pathways.
abstract: IL-4 and IL-13 are related cytokines which induce both pro- and anti-inflammatory effects depending on the cell type they act upon and the nature of the receptors expressed. The type I receptor complex is composed of the IL-4Ralpha and gammac and only binds IL-4, whereas, in the type II receptor, IL-4Ralpha dimerizes with IL-13Ralpha1 upon either IL-4 or IL-13 binding. Another ligand binding chain potentially implicated in the IL-4/IL-13 receptor has been described, the IL-13Ralpha2, but the regulation of its expression and its role in IL-4/IL-13 transduction is poorly understood. In this study we report that IL-4 and IL-13 upregulate IL-13Ralpha2 at both the mRNA and protein levels in the keratinocyte cell line HaCaT. In these cells, IL-4 or IL-13 were shown to activate the Janus Kinases JAK1 and JAK2, the transcription factor STAT6, and the ERK and p38 mitogen-activated protein kinases. We show that IL-4 or IL-13-induced IL-13Ralpha2 mRNA expression was inhibited by the ERK inhibitor U0126, the JAK inhibitor AG490 and, to a lesser extent, the p38 MAPK inhibitor SB203580. Moreover, expression of a constitutive active mutant of STAT6 alone did not modify IL-13Ralpha2 mRNA expression, but potentiated the effects of IL-4 or IL-13 on IL-13Ralpha2 expression. The constitutive active mutants of MEK1 or MKK6 increased the level of expression of IL-13Ralpha2 mRNA even in absence of stimulation. Our findings demonstrate, for the first time, that IL-4 and IL-13 can induce IL-13Ralpha2 expression in keratinocytes, and that the ERK and p38 MAPK together with JAK2 and STAT6 play a critical role in this process.
authors.affiliation: INSERM U461, Faculte de Pharmacie, 5, rue JB Clement, 92296 Chatenay Malabry Cedex, France.
authors.forename: M
authors.initials: M
authors.lastname: David
authors.forename: D
authors.initials: D
authors.lastname: Ford
authors.forename: J
authors.initials: J
authors.lastname: Bertoglio
authors.forename: A L
authors.initials: AL
authors.lastname: Maizel
authors.forename: J
authors.initials: J
authors.lastname: Pierre
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology; D015153:Blotting, Western; D002070:Butadienes / Q000494:pharmacology; D003432:Cross-Linking Reagents / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015972:Gene Expression Regulation, Neoplastic; D007093:Imidazoles / Q000494:pharmacology; D018793:Interleukin-13 / Q000378:metabolism*; D053661:Interleukin-13 Receptor alpha1 Subunit; D015847:Interleukin-4 / Q000378:metabolism*; D015603:Keratinocytes / Q000378:metabolism*; D007700:Kinetics; D008024:Ligands; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D009570:Nitriles / Q000494:pharmacology; D010957:Plasmids / Q000378:metabolism; D011233:Precipitin Tests; D011485:Protein Binding; D011725:Pyridines / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D018123:Receptors, Interleukin / Q000235:genetics* / Q000378:metabolism*; D053660:Receptors, Interleukin-13; D020133:Reverse Transcriptase Polymerase Chain Reaction; D050800:STAT6 Transcription Factor; D015398:Signal Transduction; D013997:Time Factors; D015534:Trans-Activators / Q000378:metabolism*; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured; D020032:Tyrphostins / Q000494:pharmacology; D048051:p38 Mitogen-Activated Protein Kinases
chemical_list: D000970:Antineoplastic Agents; D002070:Butadienes; D003432:Cross-Linking Reagents; D004791:Enzyme Inhibitors; C508181:IL13RA1 protein, human; D007093:Imidazoles; D018793:Interleukin-13; D053661:Interleukin-13 Receptor alpha1 Subunit; D008024:Ligands; D009570:Nitriles; D011725:Pyridines; D012333:RNA, Messenger; D018123:Receptors, Interleukin; D053660:Receptors, Interleukin-13; D050800:STAT6 Transcription Factor; D015534:Trans-Activators; D020032:Tyrphostins; C113580:U 0126; C095512:alpha-cyano-(3,4-dihydroxy)-N-benzylcinnamide; D015847:Interleukin-4; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; C093642:SB 203580