TABLE1.

Interaction between ISG15 and viral proteins.

Viral proteins	Biological effects after ISGylation	Impact on viral infection	Reference
IVA NS1	ISG15 inhibits viral proteins nuclear translocation and restores host antiviral responses	Inhibits IBV replication	(Tang et al., 2010; Zhao et al., 2010)
IBV NPs	ISGylation of NPs inhibit the oligomerization of unmodified NPs, which impedes viral RNA synthesis	Inhibits IBV replication	Zhao et al. (2016)
CVB3 2Apro	ISG15 inhibits its protease activity to restore host protein translation	Inhibits CVB3 replication	Rahnefeld et al. (2014)
HIV Gag	ISG15 inhibits the monoubiquitination of Gag protein and block its interaction with TSG101	Inhibits the emergence and release of HIV.	Okumura et al. (2006)
EBOV VP40	ISGylation of NEDD4 ubiquitin-binding enzyme inhibits its interaction with VP40	Inhibits the budding and release of Ebola virus	(Yasuda et al., 2003; Okumura et al., 2008)
ASLV Gag	The ISGylation of CHMP5 limits the membrane recruitment of Vps4 and its interaction with the ASLV Gag	Inhibits the ASLV budding complex, then inhibits the release of intracellular virus-like particles	Pincetic et al. (2010)
SARS PLpro MERS PLpro	PLpro protease is a virus-encoded DUB, which active on ubiquitin like molecule ISG15	Negatively regulates the innate immune response to the virus	Rut et al. (2020)