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PreprintCited by 21Enzyme Structure and FunctionAnimal Disease Management and EpidemiologyGenomics and Chromatin Dynamics

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Structure of the recombinant RNA polymerase from African Swine Fever Virus

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Werner, Finn, Pilotto, Simona, Sýkora, Michal, Cackett, Gwenny, Dulson, Christopher·2023·Nature Communications
DOI 10.21203/rs.3.rs-3254640/v1PMC PMC10881513

Preprint — published as 10.1038/s41467-024-45842-7 · Paper page

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Abstract

African Swine Fever Virus (ASFV) is a Nucleo-Cytoplasmic Large DNA Virus which causes an incurable haemorrhagic fever in wild and domesticated pigs with a high impact on global food security. ASFV replicates in the cytoplasm of the infected cell and encodes its own transcription machinery that is independent of cellular factors. Little is known about how this system works at a molecular level and there are currently no approved vaccines nor antiviral drugs to treat the disease. Here, we present methods to produce recombinant ASFV RNA polymerase (RNAP), functional assays suitable to screen for inhibitors, and high-resolution cryo-Electron Microscopy structures of the viral RNAP in different conformational states. The viral RNAP bears a striking resemblance to RNAPII with bona fide homologs of nine of its twelve subunits. Key differences include the fusion of assembly platform subunits RPB3 and RPB11, and an unusual C-terminal domain of the stalk subunit vRPB7 that is related to the eukaryotic mRNA cap 2´-O-methyl transferase 1. Despite the structural conservation with eukaryotic and bacterial polymerases, the ASFV RNAP is resistant to the inhibitors rifampicin and alpha-amanitin, offering the grounds for the development of highly selective inhibitors. The cryo-EM structures and fully recombinant RNAP system together provide an important tool for the design, development, and screening of antiviral drugs in a low biosafety containment environment.

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Metadata

Authors
Werner, F., Pilotto, S., Sýkora, M., Cackett, G., & Dulson, C.
Affiliations
Institute of Structural and Molecular Biology (GB)
Corresponding author
Werner, Finn
ORCID
Venue
Nature Communications
Publisher
Springer Science and Business Media LLC
Published
2023-09-14
Volume
15
Issue
1
Pages
1606-1606
ISSN
2041-1723 (ISSN-L)
DOI
10.21203/rs.3.rs-3254640/v1
PMC
PMC10881513
OpenAlex
W4391991430
Cited by
21
References
1
Citations by year
2026: 10 · 2025: 8 · 2024: 3
FWCI
2.05
Type
journal article
Language
en
Open access
Licence
Locations
  • Nature Communications (publishedVersion, cc-by)
  • Research Square (acceptedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • UCL Discovery (University College London) (submittedVersion, cc-by)
  • RePEc: Research Papers in Economics (submittedVersion)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion)
Funders
  • Wellcome Trust (202679/Z/16/Z, Z/17/Z, WT207446/Z/17/Z, 202679, 206166/Z/17/Z, 206166)
  • Research Councils UK (BB/X017028/1)
  • University of St Andrews
  • Julius-Maximilians-Universität Würzburg
  • Biotechnology and Biological Sciences Research Council (BB/X017028/1, BB/T027686/1)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Structural Biology › Enzyme Structure and Function
  • Life Sciences › Agricultural and Biological Sciences › Animal Science and Zoology › Animal Disease Management and Epidemiology
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Genomics and Chromatin Dynamics
Keywords
African swine fever virus, viral RNA polymerase, recombinant protein expression, cryo-EM structure, Rpb3, rifampicin resistance, alpha-amanitin resistance, antiviral drug screening
MeSH terms
African Swine Fever, African Swine Fever Virus, Animals, RNA, DNA-Directed RNA Polymerases, Swine, Cryoelectron Microscopy, Sus scrofa

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