. "Viral protein involved in the evasion of the type I, II and III interferon pathways by inhibiting the STAT1 protein. Upon viral infection, STAT1 is activated by IFN-gamma, IFN-alpha/beta, or IFN-lambda that bind to specific cell surface receptors. While IFN-gamma induces STAT1 homodimerization, IFN-alpha/beta and IFN-lambda stimulate heterodimerization of STAT1 and STAT2, both leading to STAT1 nuclear localization and subsequent induction of IFN-stimulated genes. Many viruses interfere with STAT1 activation, often by preventing STAT1 phosphorylation and nuclear localization." . . "Inhibition of host STAT1 by virus" . .