Orthopoxvirus (taxid:10242)
VIRION

Enveloped, brick-shaped virion, 250nm long and 200nm wide. The surface membrane displays surface tubules or surface filaments. Two distinct infectious virus particles exists: the intracellular mature virus (IMV) and the extracellular enveloped virus (EEV).
GENOME
Linear, dsDNA genome of 170-250kb. The linear genome is flanked by inverted terminal repeat (ITR) sequences which form covalently closed hairpin termini at each extremity.
GENE EXPRESSION
ENZYMES
- DNA-directed DNA polymerase [E9L (OPG071)]
- DNA-directed RNA polymerase [E4L (OPG066)]
- Cell-type capping
- RNA TPase [D1R (OPG113)]
- GTase [D1R (OPG113)]
- N7MTase [D1R (OPG113) + D12L (OPG124)]
- 2'O methylase [J3R (OPG102)]
- Core protease (Peptidase C57) [I7 (OPG083)]
- Metalloprotease (Peptidase M44) [G1L (OPG085)]
- Phospholipase [F13 (OPG057)]
REPLICATION
CYTOPLASMIC
- Attachement of the viral proteins to host glycosaminoglycans (GAGs) mediates endocytosis of the virus into the host cell. The virus can be uptaked also by apoptotic mimicry
- Fusion with the plasma membrane to release the core into the host cytoplasm.
- Early phase: early genes are transcribed in the cytoplasm by viral RNA polymerase. Early expression begins at 30 minutes post-infection.
- Core is completely uncoated as early expression ends, viral genome is now free in the cytoplasm.
- Intermediate phase: Intermediate genes are expressed, triggering genomic DNA replication at approximately 100 minutes post-infection.
- Late phase: Late genes are expressed from 140 min to 48 hours post-infection, producing all structural proteins.
- Assembly of progeny virions starts in cytoplasmic viral factories, producing an spherical immature particle. This virus particle matures into brick-shaped intracellular mature virion (IMV).
- IMV virion can be released upon cell lysis, or can acquire a second double membrane from trans-Golgi and bud as external enveloped virion (EEV).
Host-virus interaction
Adaptive immune response inhibition
The vaccinia virus A35R localizes to host endosomes and inhibits MHC class II antigen presentation .
Apoptosis modulation
Several poxviral proteins are dedicated to the inhibition of host apoptosis. Vaccinia F1L functions both as a suppressor of proapoptotic Bcl-2 family proteins and as an inhibitor of caspase-9 .
Autophagy modulation
Vaccinia virus actively disrupts the cellular autophagy through a mechanism that involves aberrant LC3 lipidation and a direct conjugation between ATG12 and ATG3 .
NF-kappa-B modulation
The B14 protein from vaccinia virus functions by binding to the IKK complex via an interaction with IKK-beta and preventing the phosphorylation of IKK-beta on its activation loop. In turn, IKK-beta is not activated and fails to phosphorylate IkB-beta, leaving IkB-beta able to retain NF-kappa-B in the cytoplasm .
Innate immune response inhibition
Poxviruses inhibit the cascade leading to production of interferon-beta by mainly targeting the host IRF3 protein. For instance, vaccinia virus protein C6 inhibits IRF3 activation downstream of TBK1 .
Matching UniProtKB/Swiss-Prot entries
(all links/actions below point to uniprot.org website)1204 entries grouped by strain
Vaccinia virus (strain Copenhagen) (VACV) reference strain
256 entries
Vaccinia virus (strain Western Reserve) (VACV) (Vaccinia virus (strain WR)) reference strain
218 entries
Monkeypox virus reference strain
168 entries
Variola virus (isolate Human/India/Ind3/1967) (VARV) (Smallpox virus) reference strain
159 entries
Camelpox virus (strain CMS) reference strain
19 entries
Vaccinia virus (strain Copenhagen) (VACV)
1 entry
Vaccinia virus (strain Western Reserve) (VACV) (Vaccinia virus (strain WR))
13 entries
Monkeypox virus
1 entry
Variola virus
107 entries
Vaccinia virus (strain Ankara) (VACV)
82 entries
Vaccinia virus (strain Tian Tan) (VACV)
33 entries
Rabbitpox virus (strain Utrecht) (RPV)
22 entries
Camelpox virus (strain M-96)
19 entries
Cowpox virus (strain GRI-90 / Grishak) (CPV)
19 entries
Cowpox virus (strain Brighton Red) (CPV)
18 entries
Vaccinia virus (strain L-IVP) (VACV)
18 entries
Ectromelia virus (strain Moscow) (ECTV) (Mousepox virus)
15 entries
Monkeypox virus (strain Zaire-96-I-16) (MPX)
11 entries
Horsepox virus (HSPV)
3 entries
Raccoon poxvirus (RCN)
3 entries
Vaccinia virus (strain Dairen I) (VACV)
3 entries
Vaccinia virus (strain LC16m0) (VACV)
3 entries
Vaccinia virus (strain LC16m8) (VACV)
3 entries
Vaccinia virus (strain Lister) (VACV)
3 entries
Cowpox virus (CPV)
2 entries
Vaccinia virus (strain IHD-J) (VACV)
2 entries
Camelpox virus (strain CP-1)
1 entry
Vaccinia virus (strain Tashkent) (VACV)
1 entry
Vaccinia virus (strain WR 65-16) (VACV)
1 entry
Cowpox virus taxid:10243
Cowpox virus (strain Brighton Red) taxid:265872
Horsepox virus taxid:397342
Raccoon poxvirus taxid:10256
Vaccinia virus taxid:10245
Vaccinia virus (strain Ankara) taxid:126794
Vaccinia virus (strain Copenhagen) taxid:10249
Protein | ModelArchive |
Protein OPG157 | ma-jd-viral-44671 |
Scaffold protein OPG125 (62 kDa protein) (Rifampicin resistance protein) | ma-jd-viral-18034 |
Vaccinia virus (strain L-IVP) taxid:31531
Vaccinia virus (strain Tian Tan) taxid:10253
Protein | ModelArchive |
Phosphoprotein OPG062 (Phosphoprotein F17) | ma-jd-viral-63871 |