IRF7
IRF7 (interferon regulatory factor 7) is a member of the IRF family of transcription factors and a key regulator of type I interferon-dependent immune responses. It drives the innate immune response against DNA and RNA viruses by inducing interferon-alpha and interferon-beta genes. Browse Assay Genie's current range of IRF7 research reagents below, or read on for the biology behind the target.
IRF7 is a transcription factor that regulates type I interferon (IFN) genes and IFN-stimulated genes (ISGs). It binds an interferon-stimulated response element (ISRE) in their promoters and can efficiently activate both the IFN-beta and IFN-alpha genes. Induction occurs through the virus-activated, MyD88-independent pathway and the TLR-activated, MyD88-dependent pathway. IRF7 is required in both the early and late phases of IFN gene induction, and is more critical in the late phase.
In uninfected cells IRF7 exists in an inactive form in the cytoplasm. After viral infection, double-stranded RNA (dsRNA) or toll-like receptor (TLR) signalling, it is phosphorylated by the kinases IKBKE and TBK1. This causes a conformational change that leads to dimerisation and nuclear localisation, where IRF7 and other coactivators activate transcription of type I IFN and ISG genes. It also induces transcription of the ubiquitin hydrolase USP25 in response to lipopolysaccharide (LPS) or viral infection, in a type I IFN-dependent manner. According to NCBI Gene, inducible expression of the IRF7 gene is largely restricted to lymphoid tissue.
Beyond innate antiviral defence, IRF7 can influence adaptive immune responses by inducing PSMB9/LMP2 expression, either directly or through IRF1. It binds the Q promoter (Qp) of EBV nuclear antigen 1 (EBNA1) and may help regulate EBV latency. It can also activate distinct gene expression programmes in macrophages and regulate the anti-tumour properties of primary macrophages. IRF7 belongs to the interferon regulatory factors gene group, alongside IRF1, IRF3 and IRF5, among others. The mouse ortholog is Irf7.
IRF7 is central to the innate response against DNA and RNA viruses, making it a core factor for studying virus-induced interferon production.
IRF7 regulates IFN-alpha, IFN-beta and ISG transcription via ISRE binding, so it is widely studied in interferon induction pathways.
IRF7 is activated by TBK1 and IKBKE following dsRNA or TLR signalling, linking pathogen sensors to interferon gene expression.
IRF7 can drive distinct gene expression programmes in macrophages and regulate the anti-tumour properties of primary macrophages.
IRF7 is a key transcriptional regulator of type I interferon responses. Once phosphorylated by TBK1 and IKBKE, it dimerises, moves to the nucleus and activates IFN-alpha, IFN-beta and interferon-stimulated genes, supporting innate defence against DNA and RNA viruses.
In uninfected cells IRF7 is held in an inactive form in the cytoplasm. After viral infection, dsRNA or TLR signalling, phosphorylation triggers dimerisation and nuclear localisation, where it acts on target gene promoters. UniProt lists both nucleus and cytoplasm as locations.
IRF7 belongs to the IRF family of transcription factors, which also includes IRF1, IRF3 and IRF5. A mouse ortholog, Irf7, is annotated. IRF7 can induce IRF1-linked PSMB9/LMP2 expression. Check the datasheet of any product for its validated reactivity.
Other interferon regulatory factors that act alongside IRF7 in interferon and innate immune signalling.
Gene and protein annotations from HGNC, NCBI Gene and UniProt Q92985; product specifications from Assay Genie datasheets.