CGAS and infection: It was demonstrated that cGAS-STING signaling is vital for the host defense against virus infection, as proved by the evidence that fibroblasts and bone marrow-derived macrophages from cGAS−/− mice were defective in IFN-β production and viral clearance during DNA virus MHV68 infection, and cGAS−/− mice were also more susceptible to RNA virus lethal infections [31].