title: Individual interferon regulatory factor-3 thiol residues are not critical for its activation following virus infection.
abstract: The interferon regulatory factor (IRF)-3 transcription factor plays a central role in the capacity of the host to mount an efficient innate antiviral immune defense, mainly through the regulation of type I Interferon genes. A tight regulation of IRF-3 is crucial for an adapted intensity and duration of the response. Redox-dependent processes are now well known to regulate signaling cascades. Recent reports have revealed that signaling molecules upstream of IRF-3, including the mitochondrial antiviral-signalling protein (MAVS) and the TNF receptor associated factors (TRAFs) adaptors, are sensitive to redox regulation. In the present study, we assessed whether redox regulation of thiol residues contained in IRF-3, which are priviledged redox sensors, play a role in its regulation following Sendai virus infection, using a combination of mutation of Cysteine (Cys) residues into Alanine and thiols alkylation using N-ethyl maleimide. Alkylation of IRF-3 on Cys289 appears to destabilize IRF-3 dimer in vitro. However, a detailed analysis of IRF-3 phosphorylation, dimerization, nuclear accumulation, and induction of target gene promoter in vivo led us to conclude that IRF-3 specific, individual Cys residues redox status does not play an essential role in its activation in vivo.
authors: CRCHUM-Centre Hospitalier de l'Université de Montréal, Montréal, Quebec, Canada.
authors: Nicolas
authors: N
authors: Zucchini
authors: Virginie
authors: V
authors: Williams
authors: Nathalie
authors: N
authors: Grandvaux
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000235:genetics / Q000276:immunology; D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D000478:Alkylation; D019943:Amino Acid Substitution; D000818:Animals; D002461:Cell Line, Transformed; D002467:Cell Nucleus / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D005033:Ethylmaleimide / Q000737:chemistry; D050838:Interferon Regulatory Factor-3 / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D007370:Interferon Type I / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D051379:Mice; D018345:Mice, Knockout; D020125:Mutation, Missense; D011401:Promoter Regions, Genetic / Q000235:genetics / Q000276:immunology; D055503:Protein Multimerization; D010253:Respirovirus Infections / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D029082:Sendai virus / Q000276:immunology / Q000378:metabolism*; D047988:Tumor Necrosis Factor Receptor-Associated Peptides and Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D005033:Ethylmaleimide; D050838:Interferon Regulatory Factor-3; D007370:Interferon Type I; D047988:Tumor Necrosis Factor Receptor-Associated Peptides and Proteins; C512612:MAVS protein, mouse; C494233:Irf3 protein, mouse