Synthesized 2′,3′-cGAMP interacts with ER-resident STING and triggers downstream signaling of type I IFNs through TBK1 and IKK, inducing the activation of IRF3 and releasing cytokines, including type I IFNs, the first line of defense against viral infections (50, –, 55). Here, TBK1 is linked to viral infectious disease.