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Published on: September 27, 2014
African swine fever virus replication and genomics
Linda K Dixon1, David A G Chapman, Christopher L Netherton
1The Pirbright Institute, Ash Road, Pirbright, Woking, Surrey GU24 0NF, United Kingdom. linda.dixon@pirbright.ac.uk
Virus Research
|November 13, 2012
Summary
African swine fever virus (ASFV) is a large DNA virus with a complex genome. Its replication and transcription occur independently of the host, with unique features for evading defenses.
Area of Science:
- Virology
- Molecular Biology
- Genomics
Background:
- African swine fever virus (ASFV) is a large, icosahedral DNA virus.
- It replicates in the cytoplasm and possesses a genome of 170-193 kbp with 150-167 open reading frames.
Purpose of the Study:
- To detail the genomic structure and replication mechanisms of ASFV.
- To explore ASFV's strategies for host immune evasion and cellular modulation.
Main Methods:
- Genomic analysis of ASFV structure, including termini and repeat arrays.
- Investigation of viral transcription and replication processes, including enzyme roles.
- Comparative analysis of ASFV genome variations across isolates.
Main Results:
- ASFV genome termini feature hairpin loops and tandem repeats; replication intermediates suggest a poxvirus-like mechanism.
- Viral transcription is independent of host RNA polymerase II, with virions containing necessary enzymes.
- ASFV encodes enzymes for replication, transcription, and host defense evasion, with genome variation primarily due to multigene family dynamics.
Conclusions:
- ASFV exhibits unique replication and transcription strategies, independent of the host cell machinery.
- The virus possesses sophisticated mechanisms for evading host defenses and manipulating cell functions.
- Genomic variability in ASFV is largely driven by changes in specific multigene families.
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