description | Viral protein involved in the evasion of host immune defense by inhibiting the ISG15 protein, an ubiquitin-like modifier playing important roles in the innate immune response. Like ubiquitin, ISG15 is conjugated to lysines on numerous target proteins through its conserved C-terminal region. Viruses escape from the antiviral activity of ISG15 by direct interaction or by cleavage of ISG15 derivatives |