Negative regulator of innate antiviral response. Blocks IRF3-dependent cytokine production such as IFNA, IFNB and TNF (PubMed:29802199). Interacts with IRF3 and inhibits IRF3 recruitment to type I IFN promoter sequences while also reducing nuclear levels of the coactivators EP300 and CREBBP (PubMed:29802199). Interacts with IRF3; the interaction inhibits IRF3 binding to its DNA consensus sequence. Expressed in lung (at protein level). Expression is icreased in presence of dsRNA such as poly(I:C).