ASFV DNA polymerse X is extremely error-prone under diverse assay conditions and within multiple DNA sequence contexts. (1/6)
We previously demonstrated that the DNA repair system encoded by the African swine fever virus (ASFV) is both extremely error-prone during the single-nucleotide gap-filling step (catalyzed by ASFV DNA polymerase X) and extremely error-tolerant during the nick-sealing step (catalyzed by ASFV DNA ligase). On the basis of these findings we have suggested that at least some of the diversity known to exist among ASFV isolates may be a consequence of mutagenic DNA repair, wherein damaged nucleotides are replaced with undamaged but incorrect nucleotides by Pol X and the resultant mismatched nicks are sealed by ASFV DNA ligase. Recently, this hypothesis appeared to be discredited by Salas and co-workers [(2003) J. Mol. Biol. 326, 1403-1412], who reported the fidelity of Pol X to be, on average, 2 orders of magnitude higher than what we previously published. In an effort to address this discrepancy and provide a definitive conclusion about the fidelity of Pol X, herein we examine the fidelity of Pol X-catalyzed single-nucleotide gap-filling in both the steady state and the pre-steady state under a diverse array of assay conditions (varying pH and ionic strength) and within different DNA sequence contexts. These studies corroborate our previously published data (demonstrating the low fidelity of Pol X to be independent of assay condition/sequence context), do not reproduce the data of Salas et al., and therefore confirm Pol X to be one of the most error-prone polymerases known. These results are discussed in light of ASFV biology and the mutagenic DNA repair hypothesis described above. (+info)Recombinant antigen targets for serodiagnosis of African swine fever. (2/6)
(+info)Eukaryotic large nucleo-cytoplasmic DNA viruses: clusters of orthologous genes and reconstruction of viral genome evolution. (3/6)
(+info)Evolution of DNA ligases of nucleo-cytoplasmic large DNA viruses of eukaryotes: a case of hidden complexity. (4/6)
(+info)Development and validation of a multiplex, real-time RT PCR assay for the simultaneous detection of classical and African swine fever viruses. (5/6)
(+info)Prevalence of African swine fever virus in apparently healthy domestic pigs in Uganda. (6/6)
(+info)Asfarviridae is a family of large, double-stranded DNA viruses that includes a single genus, Asfivirus. The most well-known member of this family is the African swine fever virus (ASFV), which causes a highly contagious and often fatal disease in domestic pigs and wild boars. ASFV can also infect a variety of other animals, including warthogs, bushpigs, and soft ticks.
The name "Asfarviridae" comes from the acronym "ASF-like viruses" and the Arabic word "asfar," which means "yellow," in reference to the yellow color of ASFV virions (virus particles) when viewed under an electron microscope.
ASFV is a complex virus that encodes many proteins involved in various aspects of its replication cycle, including entry into host cells, DNA replication, transcription, and assembly of new virions. It can cause a wide range of clinical signs in infected animals, from mild fever and loss of appetite to severe hemorrhagic disease with high mortality rates.
There is currently no effective vaccine or treatment for African swine fever, and the virus poses a significant threat to the global pig industry. Researchers are actively studying ASFV and related viruses in order to better understand their biology and develop new strategies for prevention and control.