Figure 3.

K-bZIP inhibits antiviral innate immune signaling and anti-proliferative signaling. Viral cytosolic dsDNA activates the cGAS/STING pathway, which recruits TBK1 to phosphorylate and activate IRF3. IRF3 transitions to the nucleus to turn on expression of antiviral type 1 IFN genes. The early lytic viral transcription factor K-bZIP prevents IRF3 promoter access to inhibit IFN-β production. K-bZIP inhibits p53 and CDK2 but activates p21 to cause G₀/G₁ cell cycle arrest and prevent apoptosis. K-bZIP also prevents the association of p300/CBP with Smad proteins to inhibit expression of TGF-β-responsive genes in response to TGF-β signaling.