Interferon regulatory factor 1,Interferon regulatory factor 1 isoform +I9,Interferon regulatory factor 1 isoform d78,Interferon regulatory factor 1 isoform delta4,Interferon regulatory factor 1 isoform delta7,IRF 1,IRF-1,IRF1,IRF1,MAR,MAR1,IRF1 encodes interferon regulatory factor 1, a member of the interferon regulatory transcription factor (IRF) family. IRF1 serves as an activator of interferons alpha and beta transcription, and in mouse it has been shown to be required for double-stranded RNA induction of these genes. IRF1 also functions as a transcription activator of genes induced by interferons alpha, beta, and gamma. Further, IRF1 has been shown to play roles in regulating apoptosis and tumor-suppressoion.