CGAS and infection: On the other hand, various reports have demonstrated that the expression of type I IFNs and downstream interferon-stimulating genes (ISGs) following infection with certain RNA viruses is abrogated in cGas-/- and Mita-/- knockout cells, suggesting that the cGAS-MITA/STING pathway also participates in the innate immune response to certain RNA viruses [48, 116–120].