Initially described as a transcription factor able to activate expression of the cytokine Interferon beta,[6] IRF-1 was subsequently shown to function as a transcriptional activator or repressor of a variety of target genes.

IRF-1 regulates expression of target genes by binding to an interferon stimulated response element (ISRE) in their promoters.

Beyond its function as a transcription factor, IRF-1 has also been shown to trans-activate the tumour suppressor protein p53 through the recruitment of its co-factor p300.

[8] IRF-1 has been shown to play roles in the immune response, regulating apoptosis, DNA damage and tumor suppression.

[10] IRF1 has been shown to interact with: This article incorporates text from the United States National Library of Medicine, which is in the public domain.