Fig. 1.

The CGAS-STING1 pathway. A critical cytosolic DNA sensor, CGAS elicits robust innate immune responses through the production of 2′3′-cGAMP, which binds and activates STING1 in response to DNA from pathogens or hosts. In addition, bacteria-produced CDNs can directly activate STING1 in a CGAS-independent manner. Activated STING1 exits the ER membrane and travels to Golgi via the ERGIC, leading to the production of type I IFNs by activating the TBK1-IRF3 pathway. STING1 also activates NFKB1-dependent pro-inflammatory cytokine expression. CDNs cytosolic cyclic dinucleotides, cGAMP cyclic GMP-AMP, CGAS cyclic GMP-AMP synthase, ER endoplasmic reticulum, ERGIC endoplasmic reticulum-Golgi intermediate compartment, IFN interferon, IKK IκB kinase, IRF3 interferon regulatory factor 3, NFKB1 nuclear factor kappa B subunit 1, STING1 stimulator of interferon response cGAMP interactor 1, TBK1 TANK binding kinase 1