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Journal of virology1997; 71(12); 9627-9639; doi: 10.1128/JVI.71.12.9627-9639.1997

Novel and dynamic evolution of equine infectious anemia virus genomic quasispecies associated with sequential disease cycles in an experimentally infected pony.

Abstract: We have investigated the genetic evolution of three functionally distinct regions of the equine infectious anemia virus (EIAV) genome (env, rev, and long terminal repeat) during recurring febrile episodes in a pony experimentally infected with a well-characterized reference biological clone designated EIAV(PV). Viral populations present in the plasma of an EIAV(PV)-infected pony during sequential febrile episodes (18, 34, 80, 106, and 337 days postinfection) were amplified from viral RNA, analyzed, and compared to the inoculated strain. The comparison of the viral quasispecies showed that the inoculated EIAV(PV) quasispecies were all represented during the first febrile episode, but entirely replaced at the time of the second febrile episode, and that new predominant quasispecies were associated with each subsequent cycle of disease. One of the more surprising results was the in vivo generation of large deletion (up to 15 amino acids) in the principal neutralizing domain (PND) of gp90 during the third febrile episode. This deletion did not alter the competence for in vitro replication as shown by the analysis of a env chimeric clone with a partially deleted PND and did not altered the fitness of the virus in vivo, since this partially deleted envelope became the major population during the fourth febrile episode. Finally, we showed that the amino acid mutations were not randomly distributed but delineated eight variables regions, V1 to V8, with V3 containing the PND region. These studies provide the first detailed description of the evolution of EIAV genomic quasispecies during persistent infection and reveal new insights into the genetics and potential mechanisms of lentivirus genomic variation.
Publication Date: 1997-11-26 PubMed ID: 9371627PubMed Central: PMC230271DOI: 10.1128/JVI.71.12.9627-9639.1997Google Scholar: Lookup
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  • Journal Article
  • Research Support
  • Non-U.S. Gov't
  • Research Support
  • U.S. Gov't
  • P.H.S.

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This research investigates how three distinct parts of the Equine Infectious Anemia Virus (EIAV) genome evolve during recurring instances of fever in a pony infected with a specific version of the virus. All strains of the initial virus were present during the first fever episode, replaced by new strains in the second episode, with further new strains associated with each subsequent fever cycle.

Research Methodology

  • The team studied the genetic evolution of three functionally distinct regions of the equine infectious anemia virus (EIAV) genome: env, rev, and long terminal repeat.
  • A pony was experimentally infected with a well-characterized reference biological clone designated EIAV(PV).
  • Viral populations present during sequential febrile episodes (18, 34, 80, 106, and 337 days postinfection) were amplified from viral RNA, analyzed, and compared to the inoculated strain.

Research Findings

  • It was observed that all original EIAV(PV) quasispecies were present during the first febrile episode, but were entirely replaced by the time of the second febrile episode.
  • New predominant quasispecies were associated with each subsequent cycle of disease.
  • Interestingly, there was the in vivo generation of large deletion (up to 15 amino acids) in the principal neutralizing domain (PND) of gp90 during the third febrile episode.
  • Analysis of an env chimeric clone with a partially deleted PND showed that this deletion did not alter the competence for in vitro replication and did not change the fitness of the virus in vivo, since this partially-deleted envelope became the major population during the fourth febrile episode.
  • Finally, the research found that the amino acid mutations were not randomly distributed. They delineated eight variable regions, V1 to V8, with V3 containing the PND region.

Significance of Findings

  • The research provides a detailed insight into the evolution of EIAV genomic quasispecies during persistent infection.
  • It offers new insights into the genetics and potential mechanisms of lentivirus genomic variation.
  • This research could play a significant role in understanding the behaviour of lentiviruses, and the development of future therapeutics and interventions.

Cite This Article

APA
Leroux C, Issel CJ, Montelaro RC. (1997). Novel and dynamic evolution of equine infectious anemia virus genomic quasispecies associated with sequential disease cycles in an experimentally infected pony. J Virol, 71(12), 9627-9639. https://doi.org/10.1128/JVI.71.12.9627-9639.1997

Publication

ISSN: 0022-538X
NlmUniqueID: 0113724
Country: United States
Language: English
Volume: 71
Issue: 12
Pages: 9627-9639

Researcher Affiliations

Leroux, C
  • Department of Molecular Genetics and Biochemistry, University of Pittsburgh School of Medicine, Pennsylvania 15261, USA.
Issel, C J
    Montelaro, R C

      MeSH Terms

      • Amino Acid Sequence
      • Animals
      • Base Sequence
      • DNA, Viral
      • Equine Infectious Anemia / physiopathology
      • Equine Infectious Anemia / virology
      • Evolution, Molecular
      • Genes, rev
      • Genetic Variation
      • Genome, Viral
      • Glycoproteins / genetics
      • Horses
      • Infectious Anemia Virus, Equine / genetics
      • Infectious Anemia Virus, Equine / physiology
      • Molecular Sequence Data
      • Neutralization Tests
      • Repetitive Sequences, Nucleic Acid
      • Sequence Deletion
      • Sequence Homology, Amino Acid
      • Sequence Homology, Nucleic Acid
      • Viral Envelope Proteins / genetics
      • Virus Replication

      Grant Funding

      • 2 P41 RR06009 / NCRR NIH HHS
      • R01AI 25850 / NIAID NIH HHS

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