Table 1.
Summary of poxvirus products with anti-apoptotic function.
| Protein | Type of Protein | Virus | Function(s) |
|---|---|---|---|
| CrmA | Serpin | CPXV | Inhibits caspase(s) activity |
| Reduces inflammation and promotes viral replication | |||
| B13 (SPI-2) | Serpin | VACV | Inhibits caspase(s) activity |
| B22 (SPI-1) | Serpin | VACV | Inhibits caspase(s) activity |
| SPI-3 | Serpin | VACV | Inhibits caspase(s) activity. Inhibits cell fusion |
| SERP1 | Serpin | MYXV | Inhibits caspase(s) activity |
| Provides full virulence | |||
| Reduces inflammation | |||
| SERP2 | Serpin | MYXV | Inhibits caspase(s) activity |
| Involved in lesion morphology | |||
| Promotes myxomatosis | |||
| SERP3 | Serpin | MYXV | Inhibits caspase(s) activity |
| Involved in lesion morphology | |||
| CrmB | vTNFR | VACV | Mimics extracellular domain of TNFR1/2 |
| Enhances virulence | |||
| CrmC | vTNFR | VACV | Mimics extracellular domain of TNFR1/2 |
| Enhances virulence | |||
| CrmD | vTNFR | ECTV | Mimics extracellular domain of TNFR1/2 |
| Possesses SECRET domain that binds to chemokines | |||
| CrmE | vTNFR | VACV | Mimics extracellular domain of TNFR1/2 |
| Enhances virulence | |||
| M-T2 | vTNFR | MYXV | Mimics extracellular domain of TNFR1/2. |
| Secreted form inhibits TNF | |||
| Intracellular form blocks virus induced lymphocyte apoptosis | |||
| T2 | vTNFR | SFV | Mimics extracellular domain of TNFR1/2 |
| Inhibits cellular TNF | |||
| A52 | Bcl-2-like folds | VACV | Inhibits IL-1 induced NF-κB activation |
| B14 | Bcl-2-like folds | VACV | Inhibits IL-1 induced NF-κB activation |
| A49 | Bcl-2-like folds | VACV | Inhibits NF-κB activation through interactions with β-TrCP |
| F1 | Bcl-2-like folds | VACV | Inhibits staurosporine induced apoptosis |
| Localizes to the mitochondria | |||
| N1 | Bcl-2-like folds | VACV | Inhibits staurosporine induced apoptosis |
| Interacts with Bad, Bax and Bid | |||
| Inhibits NF-κB activation | |||
| Localizes in cytosol | |||
| M11 | Bcl-2-like folds | MYXV | Required for virulence |
| Inhibits FasL and staurosporine induced apoptosis | |||
| Interacts with Bak and Bax | |||
| DPV022 | Bcl-2-like folds | DPV | Inhibits apoptosis induced by Bax and Bak Interacts with Bim, Bax, and Bak |
| SPPV14 | Bcl-2-like folds | SPPV14 | Inhibits intrinsic apoptosis by antagonizing Bak and Bax |
| 6L | vGAAP | CMLV | Inhibits extrinsic and intrinsic apoptosis |
| Forms ion channels reducing concentration of Ca2+ in golgi apparatus | |||
| M131 | SOD Homolog | MYXV | Binds copper chaperones for superoxide dismutase (CCS) |
| Cellular Cu-Zn SOD less active resulting in increased superoxide levels | |||
| Protects cells from apoptosis | |||
| S131 | SOD Homolog | SFV | Binds CCS |
| Cellular Cu-Zn SOD less active resulting in increased superoxide levels | |||
| Protects cells from apoptosis | |||
| Aids in virulence. | |||
| MC163 | SOD Homolog | MCV | Inhibits TNFα-induced apoptosis by preventing MMP. |
| Localizes to the mitochondria | |||
| Prevents staurosporine induced caspase 3 activation | |||
| MC066 | Seleoncystein protein | MCV | Inhibits UV and hydrogen peroxide induced apoptosis |
| A45 | SOD Homolog | VACV | Function currently unknown |
| E3 | PKR antagonist | VACV | Inhibits PKR activation by sequestering dsRNA |
| Binds to PKR | |||
| Required for virulence | |||
| M029 | E3 homolog | MYXV | Inhibits PKR activation |
| Reduces/prevents cleavage of caspase-7 and PARP-1 | |||
| SPV032 | E3 homolog | SPV | Inhibits PKR activation |
| Reduces/prevents cleavage of caspase-7 and PARP-1 | |||
| D9/D10 | Decapping enzymes | VACV | Inhibits PKR activation by reducing dsRNA accumulation |
| MC159 | vFLIP | MCV | Inhibits TNFα and FasL induced apoptosis |
| Interacts with FADD and procaspase-8 | |||
| Prevent caspase 3 and caspase 8 activation Inhibits TNFα induced NFκB activation and MAVS-induced IRF-3 activation | |||
| MC160 | vFLIP | MCV | Inhibits TNFα induced NFκB activation and MAVS- |
| induced IRF-3 activation |
Abbreviations: CPXV, Cowpox Virus; VACV, Vaccinia Virus; MYXV, Myxoma Virus; ECTV, Ectromelia Virus; SFV, Shope Fibroma Virus; MCV, Molluscum Contagiosum Virus; SPV. Swinepox Virus; CMLV, Camelpox Virus; DPV, Deerpox Virus; vTNFR, viral tumor necrosis factor receptor; vGAAP, viral Golgi anti-apoptotic protein; PKR, protein kinase R; vFLIP, viral FLICE inhibitory protein; SOD, superoxide dismutase; IL-1, interleukin-1; β-TrCP, β-transducing repeat containing protein; Bad, Bcl-2 associated death promoter; Bcl-associated X protein; Bid, BH3 interacting-domain death agonist; NF-κB, nuclear factor κ B; Bak, Bcl-2 homologous antagonist killer; Bim, Bcl-2-like protein 11; TNFα, tumor necrosis factor-α; MMP, mitochondrial membrane permeabilization; UV, ultraviolet; PARP-1, poly (ADP-ribose) polymerase 1; MAVS, mitochondrial antiviral-signaling protein; IRF-3, interferon regulatory transcription factor 3.