3DSH366327056ENSG00000128604ENSMUSG00000029771Q13568P56477NM_001347928NM_001364314NM_001252382NM_012057NM_001311083NP_001334857NP_001351243NP_001092099.1NP_001239311NP_001298012NP_036187Interferon regulatory factor 5 is a protein that in humans is encoded by the IRF5 gene. Interferon regulatory factor 5 is a protein that in humans is encoded by the IRF5 gene. IRF5 is a member of the interferon regulatory factor (IRF) family, a group of transcription factors with diverse roles, including virus-mediated activation of interferon, and modulation of cell growth, differentiation, apoptosis, and immune system activity. Members of the IRF family are characterized by a conserved N-terminal DNA-binding domain containing tryptophan (W) repeats. Alternative splice variants encoding different isoforms exist. IRF5 acts as a molecular switch that controls whether macrophages will promote or inhibit inflammation. Blocking the production of IRF5 in macrophages may help treat a wide range of autoimmune diseases, and that boosting IRF5 levels might help treat people whose immune systems are weak, compromised, or damaged. IRF5 seems to work 'either by interacting with DNA directly, or by interacting with other proteins that themselves control which genes are switched on.' This article incorporates text from the United States National Library of Medicine, which is in the public domain.