Interferon-inducible antiviral protein which plays a major role in the cell antiviral state induced by type I and type II interferon (PubMed:31812350). Catalyzes the conversion of cytidine triphosphate (CTP) to 3′-deoxy-3′,4′-didehydro-CTP (ddhCTP) via a SAM-dependent radical mechanism (PubMed:29925952, PubMed:30872404). In turn, ddhCTP acts as a chain terminator for the RNA-dependent RNA polymerases from multiple viruses and directly inhibits viral replication (PubMed:29925952). Therefore, inhibits a wide range of DNA and RNA viruses, including human cytomegalovirus (HCMV), hepatitis C virus (HCV), west Nile virus (WNV), dengue virus, sindbis virus, influenza A virus, sendai virus, vesicular stomatitis virus (VSV), zika virus, and human immunodeficiency virus (HIV-1) (PubMed:29925952, PubMed:30587778, PubMed:30934824, PubMed:31921110). Promotes also TLR7 and TLR9-dependent production of IFN-beta production in plasmacytoid dendritic cells (pDCs) by facilitating ‘Lys-63’-linked ubiquitination of IRAK1 by TRAF6 (PubMed:30872404). Plays a role in CD4+ T-cells activation and differentiation. Facilitates T-cell receptor (TCR)-mediated GATA3 activation and optimal T-helper 2 (Th2) cytokine production by modulating NFKB1 and JUNB activities. Can inhibit secretion of soluble proteins.
