TABLE 1.
Viral antagonists of interferon-stimulated genes (ISGs).
| Virus | Strain | Viral antagonist | Target ISG | Cell type | Viral evasion strategy | References |
| HSV-1 | KOS | ICP0 | IFI16 | HFF | Degrades IFI16 | Orzalli et al., 2012 |
| 17+ | ICP0 | IFI16 | U-2 OS | Does not degrade IFI16 | Cuchet-Lourenco et al., 2013 | |
| KOS, 17, F | UL41 (vhs) | IFI16 | HFF NOK, HeLa, U-2 OS | ICP0 degrades IFI16 in a cell-type specific manner; UL41 also reduces protein levels of IFI16 (presumably by RNA degradation) | Orzalli et al., 2016 | |
| F | UL41 | ZAP | 293Trex-hZAPL/S | Degrades ZAP mRNA through its endoribonuclease activity, preferentially binds ARE motifs | Su et al., 2015 | |
| F | UL41 | IFIT3 | 293T | Decreases IFIT3 expression levels by degrading IFIT3 mRNA, does not target IFIT1 or IFIT2 | Jiang et al., 2016 | |
| HCMV | AD169 | UL83 (pp65) | IFI16 | HFF | Interacts with IFI16 to block its oligomerisation and prevents signalling; promotes transcription of immediate early genes by exploiting the binding capacity of IFI16 to DNA | Li et al., 2013 |
| TB40/E | Biolatti et al., 2016 | |||||
| AD169 | Cristea et al., 2010 | |||||
| Towne (BAC-derived) | UL23 | NMI | U251 | Inhibits ISG transcription by binding to NMI and disrupting its association with STAT1 | Feng et al., 2018 | |
| Towne | IE1 (UL123) | ISG15 | HF | Inhibits HCMV-induced ISG15 expression and thereby prevents ISGylation | Kim et al., 2016 | |
| AD169 | UL26 | ISG15 | HF | Reduces the accumulation of ISGylated proteins by acting as a decoy target for ISG15 | Kim et al., 2016 | |
| Towne | ORF94 (UL126a) | OAS1 | HF | Inhibits mRNA and protein expression of OAS1, leading to reduced viral RNA degradation | Tan et al., 2011 | |
| KSHV | iSLK.219 harbouring rKSHV.219* | vIRF1 | ISG15 | 293, 293-TLR, BCBL PEL, iSLK.219 | Reduces ISGylation of cellular target proteins, leading to IRF3 instability and decreased ISG transcription; acts as a decoy target for ISG15 | Jacobs et al., 2015 |
| HuARLT2 harbouring rKSHV.219* | ORF20 | OASL | 293T, HeLa, HFF, HuARLT2-rKSHV.219 | ORF20 and OASL interact; ORF20 increases RIG-I dependent OASL expression; OASL and ORF20 concomitantly enhance KSHV infection | Bussey et al., 2018 |
*These studies used iSLK or HuARLT2 cells that were latently infected with recombinant rKSHV.219 (Vieira and O’Hearn, 2004; Myoung and Ganem, 2011; Lipps et al., 2017). HFF, human foreskin fibroblasts; HF, human fibroblasts.