title: A High Resolution Method to Monitor Phosphorylation-dependent Activation of IRF3.
abstract: The IRF3 transcription factor is critical for the first line of defense against pathogens mainly through interferon β and antiviral gene expression. A detailed analysis of IRF3 activation is essential to understand how pathogens induce or evade the innate antiviral response. Distinct activated forms of IRF3 can be distinguished based on their phosphorylation and monomer vs dimer status. In vivo discrimination between the different activated species of IRF3 can be achieved through the separation of IRF3 phosphorylated forms based on their mobility shifts on SDS-PAGE. Additionally, the levels of IRF3 monomer and dimer can be monitored using non-denaturing electrophoresis. Here, we detail a procedure to reach the highest resolution to gain the most information regarding IRF3 activation status. This is achieved through the combination of a high resolution SDS-PAGE and a native-PAGE coupled to immunoblots using multiple total and phosphospecific antibodies. This experimental strategy constitutes an affordable and sensitive approach to acquire all the necessary information for a complete analysis of the phosphorylation-mediated activation of IRF3.
authors: CRCHUM - Research center, Centre Hospitalier de l'Université de Montréal, Université de Montréal; Department of Biochemistry and Molecular Medicine, Université de Montréal; Faculty of Medicine, Université de Montréal.
authors: Alexa C
authors: AC
authors: Robitaille
authors: CRCHUM - Research center, Centre Hospitalier de l'Université de Montréal, Université de Montréal; Faculty of Medicine, Université de Montréal.
authors: Mélissa K
authors: MK
authors: Mariani
authors: CRCHUM - Research center, Centre Hospitalier de l'Université de Montréal, Université de Montréal.
authors: Audray
authors: A
authors: Fortin
authors: CRCHUM - Research center, Centre Hospitalier de l'Université de Montréal, Université de Montréal; Department of Biochemistry and Molecular Medicine, Université de Montréal; Faculty of Medicine, Université de Montréal; nathalie.grandvaux@umontreal.ca.
authors: Nathalie
authors: N
authors: Grandvaux
mesh_terms: D000918:Antibody Specificity; D045744:Cell Line, Tumor; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods*; D006801:Humans; D015151:Immunoblotting / Q000379:methods*; D050838:Interferon Regulatory Factor-3 / Q000378:metabolism*; D010766:Phosphorylation
chemical_list: C494232:IRF3 protein, human; D050838:Interferon Regulatory Factor-3