IRF1

Interferon regulatory factor 1 is a is_associated_with::protein that in humans is encoded by the IRF1 is_associated_with::gene.

Function
Interferon regulatory factor 1 was the first member of the interferon regulatory transcription factor (IRF) family identified. Initially described as a transcription factor able to activate expression of the is_associated_with::cytokine is_associated_with::Interferon beta, 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. The IRF-1 protein binds to the ISRE via an N-terminal is_associated_with::helix-turn-helix DNA binding domain, which is highly conserved among all IRF proteins.

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

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

Regulation
It has been shown that the extreme is_associated_with::C-terminus of IRF-1 regulates its ability to activate transcription, nanobodies targeting this domain (MF1) are able to increase IRF-1 activity.

Model organisms
is_associated_with::Model organisms have been used in the study of IRF1 function. A conditional is_associated_with::knockout mouse line, called Irf1tm1a(EUCOMM)Wtsi was generated as part of the is_associated_with::International Knockout Mouse Consortium program — a high-throughput mutagenesis project to generate and distribute animal models of disease to interested scientists — at the is_associated_with::Wellcome Trust Sanger Institute.

Male and female animals underwent a standardized is_associated_with::phenotypic screen to determine the effects of deletion. Twenty five tests were carried out and two is_associated_with::phenotypes were reported. is_associated_with::Homozygous is_associated_with::mutant animals had abnormal is_associated_with::peripheral blood lymphocytes, specifically decreased is_associated_with::CD8-positive is_associated_with::T cell and is_associated_with::NK cell numbers and an increase in is_associated_with::CD4-positive T cells. The mice also had an abnormal is_associated_with::integument phenotype determined by a study of tail epidermis.

Interactions
IRF1 has been shown to interact with:
 * CHIP
 * is_associated_with::GAGE
 * is_associated_with::HSP70 / is_associated_with::HSP90
 * is_associated_with::IRF8
 * is_associated_with::KPNA2
 * is_associated_with::MYD88
 * is_associated_with::PCAF
 * is_associated_with::STAT1
 * TAT
 * is_associated_with::VEGFR2