title: Regulation of IFN-λ1 promoter activity (IFN-λ1/IL-29) in human airway epithelial cells.
abstract: The type III (λ) IFNs (IFN-λ1, IFN-λ2, and IFN-λ3) and their receptor are the most recently discovered IFN family. They are induced by viruses and mediate antiviral activity, but type III IFNs have an important, specific functional niche at the immune/epithelial interface, as well as in the regulation of Th2 cytokines. Their expression appears diminished in bronchial epithelial cells of rhinovirus-infected asthmatic individuals. We investigated the regulation of IFN-λ1 expression in human airway epithelial cells using reporter genes analysis, chromatin immunoprecipitation, small interfering RNA knockdown, and DNase footprinting. In this article, we define the c-REL/p65 NF-κB heterodimer and IRF-1 as key transcriptional activators and ZEB1, B lymphocyte-induced maturation protein 1, and the p50 NF-κB homodimer as key repressors of the IFN-λ1 gene. We further show that ZEB1 selectively regulates type III IFNs. To our knowledge, this study presents the first characterization of any type III IFN promoter in its native context and conformation in epithelial cells and can now be applied to understanding pathogenic dysregulation of IFN-λ1 in human disease.
authors: Genetic Immunology Laboratory, HUMIGEN LLC, Institute for Genetic Immunology, Genesis Biotechnology Group, Hamilton, NJ 08690, USA.
authors: Rachael
authors: R
authors: Siegel
authors: Joyce
authors: J
authors: Eskdale
authors: Grant
authors: G
authors: Gallagher
mesh_terms: D047369:Chromatin Immunoprecipitation; D018983:DNA Footprinting; D004797:Enzyme-Linked Immunosorbent Assay; D004847:Epithelial Cells / Q000276:immunology; D015870:Gene Expression; D005786:Gene Expression Regulation / Q000276:immunology*; D006801:Humans; D007372:Interferons; D007378:Interleukins / Q000096:biosynthesis / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic / Q000235:genetics* / Q000276:immunology; D034741:RNA, Small Interfering; D020545:Respiratory Mucosa / Q000276:immunology*; D014162:Transfection; D000095022:Interferon Lambda
chemical_list: D007372:Interferons; D007378:Interleukins; D034741:RNA, Small Interfering; C000624353:interferon-lambda, human; D000095022:Interferon Lambda