Probable DNA-binding transcriptional activator. Key determinant of the keratinocyte proliferation-differentiation switch involved in appropriate epidermal development (By similarity). Plays a role in regulating mammary epithelial cell proliferation (By similarity). May regulate WDR65 transcription (By similarity). Interacts with SERPINB5. Translocates to nucleus in response to an activating signal. Expressed in normal mammary epithelial cells. Expression is reduced or absent in breast carcinomas. Phosphorylated. Phosphorylation status depends on the cell cycle and is a signal for ubiquitination and proteasome-mediated degradation. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. Disease susceptibility is associated with variants affecting the gene represented in this entry. Belongs to the IRF family.