Fig. 10
From: Influenza A virus M2 protein triggers mitochondrial DNA-mediated antiviral immune responses

Proposed mechanism by which influenza virus regulates STING-dependent antiviral immunity. Ion channel activity of influenza virus M2 or EMCV 2B protein stimulates cytosolic mtDNA release in a MAVS-dependent manner. These cytosolic mtDNA could be packaged into distinct levels of higher-order structures depending on the ratio of TFAM to mtDNA. Cytosolic DNA sensors cGAS and DDX41 may recognize influenza virus-induced cytosolic mtDNA to stimulate STING-dependent IFN-β gene expression. The STING-dependent antiviral signaling was amplified in neighboring cells though gap junctions. The NS1 protein of influenza virus could associate with mtDNA to evade host DNA sensing pathways