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Coronavirus polyprotein processing

  • S. R. Weiss
  • S. A. Hughes
  • P. J. Bonilla
  • J. D. Turner
  • J. L. Leibowitz
  • M. R. Denison
Conference paper
Part of the Archives of Virology Supplementum book series (ARCHIVES SUPPL, volume 9)

Summary

MHV gene 1 contains two ORFs in different reading frames. Translation proceeds through ORF 1a into ORF 1b via a translational frame-shift. ORF 1a potentially encodes three protease activities, two papain-like activities and one poliovirus 3C-like activity. Of the three predicted activities, only the more amino terminal papain-like domain has been demonstrated to have protease activity. ORF 1a polypeptides have been detected in infected cells by the use of antibodies. The order of polypeptides encoded from the 5′ end of the ORF is p28, p65, p290. p290 is processed into p240 and p50. Processing of ORF1a polypeptides differs during cell free translation of genome RNA and in infected cells, suggesting that different proteases may be active under different conditions. Two RNA negative mutants of MHV-A59 express greatly reduced amounts of p28 and p65 at the non-permissive temperature. These mutants may have defects in one or more viral protease activities. ORF 1b, highly conserved between MHV and IBV, potentially contains polymerase, helicase and zinc finger domains. None of these activities have yet been demonstrated. ORF 1b polypeptides have yet been detected in infected cells.

Keywords

Infectious Bronchitis Virus Zinc Finger Domain Mouse Hepatitis Virus Cell Free Translation Coronavirus Mouse Hepatitis Virus 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag 1994

Authors and Affiliations

  • S. R. Weiss
    • 1
  • S. A. Hughes
    • 1
  • P. J. Bonilla
    • 1
  • J. D. Turner
    • 1
  • J. L. Leibowitz
    • 2
  • M. R. Denison
    • 3
  1. 1.Department of MicrobiologyUniversity of Pennsylvania School of MedicinePhiladelphiaUSA
  2. 2.Department of Pathology and Laboratory MedicineUniversity of Texas Health Sciences CenterHoustonUSA
  3. 3.Department of PediatricsVanderbilt University School of MedicineNashvilleUSA

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