Anti-Interferon regulatory factor 3 IRF3 Antibody Picoband®

IRF3 (interferon regulatory factor 3)   is a member of the interferon regulatory transcription factor (IRF) family. The IRF3 gene is mapped on 19q13.33. IRF3 is found in an inactive cytoplasmic form that upon serine/threonine phosphorylation forms a complex with  CREBBP. IRF3 plays an important role in the  innate immune system's response to  viral infection. Aggregated  MAVS  have been found to activate IRF3 dimerization. Although  IRF3  increased transcriptional activity from an ISRE-containing promoter, expression of  IRF3  as a Gal4 fusion protein did not activate expression of a chloramphenicol acetyltransferase (CAT) reporter gene containing repeats of the Gal4-binding sites.  Translocation of  IRF3  was accompanied by an increase in serine and threonine phosphorylation.  The transcriptional activators CREBBP and EP300 coimmunoprecipitated with  IRF3  only subsequent to viral infection, and the authors stated that these are also subunits of DRAF1.

A synthetic peptide corresponding to a sequence at the C-terminus of human IRF3, different from the related mouse and rat sequences by five amino acids.

Key transcriptional regulator of type I interferon (IFN) -dependent immune responses which plays a critical role in the innate immune response against DNA and RNA viruses. Regulates the transcription of type I IFN genes (IFN-alpha and IFN-beta) and IFN-stimulated genes (ISG) by binding to an interferon-stimulated response element (ISRE) in their promoters. Acts as a more potent activator of the IFN-beta (IFNB) gene than the IFN-alpha (IFNA) gene and plays a critical role in both the early and late phases of the IFNA/B gene induction. Found in an inactive form in the cytoplasm of uninfected cells and following viral infection, double-stranded RNA (dsRNA), or toll-like receptor (TLR) signaling, is phosphorylated by IKBKE and TBK1 kinases. This induces a conformational change, leading to its dimerization and nuclear localization and association with CREB binding protein (CREBBP) to form dsRNA-activated factor 1 (DRAF1), a complex which activates the transcription of the type I IFN and ISG genes. Can activate distinct gene expression programs in macrophages and can induce significant apoptosis in primary macrophages.

1. Bellingham, J., Gregory-Evans, K., Gregory-Evans, C. Y. Mapping of human interferon regulatory factor 3 (IRF3) to chromosome 19q13.3-13.4 by an intragenic polymorphic marker. Ann. Hum. Genet. 62: 231-234, 1998. 2. Doyle, S. E., Vaidya, S. A., O'Connell, R., Dadgostar, H., Dempsey, P. W., Wu, T.-T., Rao, G., Sun, R., Haberland, M. E., Modlin, R. L., Cheng, G.IRF3 mediates a TLR3/TLR4-specific antiviral gene program. Immunity 17: 251-263, 2002. 3. Stetson, D. B., Medzhitov, R. Recognition of cytosolic DNA activates an IRF3-dependent innate immune response. Immunity 24: 93-103, 2006.

Store at -20°C for one year from date of receipt. After reconstitution, at 4°C for one month. It can also be aliquotted and stored frozen at -20°C for six months. Avoid repeated freeze-thaw cycles.

Cytoplasm . Nucleus . Shuttles between cytoplasmic and nuclear compartments, with export being the prevailing effect. When activated, IRF3 interaction with CREBBP prevents its export to the cytoplasm.