Genome condensation and packaging are essential processes in the life cycle of viruses. Mimivirus and many other nucleocytoplasmic large DNA virus (NCLDV) subfamilies have evolved a unique genome packaging mechanism that is comparable to chromosome segregation in bacteria and archaea and requires a number of specific enzymes, such as packaging ATPases, recombinases, DNA polymerases, helicases, and topoisomerases, as well as histones or histone-like proteins. Although the mechanisms of assembly and genome encapsidation in African Swine Fever Virus (ASFV) have not been fully characterized, the similarities in genome structure with Poxviruses and data from electron microscopy suggest that the ASFV packaging machinery is similar to Mimivirus and other NCLDVs. ASFV encodes up to 70 structural proteins, 16 of which, at least, are thought to be involved in assembly of the virus particle and include a predicted packaging A32L ATPase (B354L), a lambda-like recombinase (D345L), a type II topoisomerase (P1192R), and the histone-like DNA-binding protein pA104R.
ORF | Description | Localization | Reference(s) |
---|---|---|---|
B646L | Major capsid protein p72 | capsid | [24][33] |
B438L | Protein p49 | capsid | [34] |
E120R | Protein p14.5 | capsid | [27] |
D117L | Major transmembrane protein p17 | inner envelope | [26][35] |
E183L | Transmembrane protein pE183L | inner envelope | [36][37] |
CP2475L | Protein p5, polyprotein pp220 derived | core shell | [38] |
CP2475L | Protein p14, polyprotein pp220-derived | core shell | [25][38][39][40] |
CP2475L | Protein p34, polyprotein pp220-derived | core shell | [25][38][39][40] |
CP2475L | Protein p37, polyprotein pp220-derived | core shell | [25][38][39][40] |
CP2475L | Protein p150, polyprotein pp220-derived | core shell | [25][38][39][40] |
CP530R | Protein p8, polyprotein pp62-derived | core shell 1 | [41] |
CP530R | Protein p15, polyprotein pp62-derived | core shell | [25][39][42] |
CP530R | Protein p35, polyprotein pp62-derived | core shell | [25][39][42] |
S273R | Polyprotein processing protease | core shell | [43][44] |
A104R | Histone-like DNA-binding protein | nucleoid | [28][38] |
K78R | DNA-binding protein p10 | nucleoid | [45] |
P1192R | Topoisomerase II | ND | [30][31] |
B354L | A32L ATPase 2 | ND | [29] |
D345L | Lambda-like recombinase 2 | ND | [10] |
This entry is adapted from the peer-reviewed paper 10.3390/vaccines8040585