This is the interferon-regulatory factor 3 chain of the hetero-dimeric structure which also contains the shorter chain CREB-binding protein. These two subunits make up the DRAF1 (double-stranded RNA-activated factor 1). Viral dsRNA produced during viral transcription or replication leads to the activation of DRAF1. The DNA-binding specificity of DRAF1 correlates with transcriptional induction of ISG (interferon-alpha,beta-stimulated gene). IRF-3 preexists in the cytoplasm of uninfected cells and translocates to the nucleus following viral infection. Translocation of IRF-3 is accompanied by an increase in serine and threonine phosphorylation, and association with the CREB coactivator occurs only after infection.