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.
Chapter PDF
Similar content being viewed by others
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.
References
Pachuk CJ, Bredenbeek PJ, Zoltick PW, Spaan WJM, Weiss SR (1989) Molecular cloning of the gene encoding the putative polymerase of mouse hepatitis virus strain A59. Virology 171: 141–148
Lee HJ, Shieh CK, Gorbalenya AE, Koonin EV, LaMonica N, Tuler J, Bagdzhadzhyan A, Lai MMC (1991) The complete sequence of the murine Coronavirus gene 1 encoding the putative protease and RNA polymerase. Virology 180: 567–582
Spaan WJM, Cavanagh D, Horzinek MC (1988) Coronaviruses. Structure and genome expression. J Gen Virol 69: 2939–2952
Sethna PB, Hung S-L, Brian DA (1989) Coronavirus subgenomic minus-strand RNAs and the potential for RNA replicons. Proc Natl Acad Sci USA 86: 5626–5630
Boursnell MEG, Brown TDK, Foulds IJ, Green PH, Tomley FM, Binns MM (1987) Completion of the sequence of the genome of the Coronavirus avian infectious bronchitis virus. J Gen Virol 68: 57–77
Bredenbeek PJ, Pachuk CJ, Noten AFH, Charite J, Luytjes W, Weiss SR, Spaan WJM (1990) The primary structure and expression of the second open reading frame of the polymerase gene of the Coronavirus MHV-A59; a highly conserved polymerase is expressed by an efficient ribosomal frameshifting mechanism. Nucleic Acids Res 18: 1825–1832
Brierly I, Boursnell MEG, Binns MM, Bilimoria B, Blok VC, Brown TDK, Inglis SC (1987) An efficient ribosomal frame-shifting signal in the polymerase encoding region of the Coronavirus IBV. EMBO J 6: 3779–3785
Gorbalenya AE, Koonin EV, Lai MMC (1991) Putative papain-related thiol proteases of positive strand RNA viruses. FEBS Lett 288: 201–205
Baker SC, Shieh CK, Chang MF, Vannier DM, Lai MMC (1989) Identification of a domain required for autoproteolytic cleavage of murine Coronavirus gene A polyprotein. J Virol 63: 3693–3699
Gorbalenya AE, Blinov VM, Donchenko AP, Koonin EV (1989) An NTP-binding domain is the most conserved seq uence in a highly diverged monophyletic group of proteins involved in positive strand RNA viral replication. J Mol Evol 28: 256–268
Gorbalenya AE, Koonin EV, Donchenko AP, Blinov VM (1992) Coronavirus genome: prediction of putative functional domains in the non-structural polyprotein by comparative amino acid sequence analysis. Nucleic Acids Res 17: 4847–4861
Studier WF, Rosenberg AH, Dunn JJ, Dubendorf JW (1990) Use of T7 polymerase to direct the expression of cloned genes. Methods Enzymol 185: 60–89
Zoltick PW, Leibowitz JL, De Vries JR, Weinstock GM, Weiss SR (1989) A general method for the induction and screening of antisera for cDNA-encoded polypeptides: antibodies specific for a Coronavirus putative polymerase encoding gene. Gene 85: 413–420
Denison MR, Perlman S (1986) Translation and processing of mouse hepatitis virus virion RNA in a cell-free system. J Virol 60: 12–18
Denison MR, Zoltick PW, Leibowitz JL, Pachuk CJ, Weiss SR (1991) Identification of polypeptides encoded in open reading frame lb of the putative polymerase gene of the murine Coronavirus mouse hepatitis virus A59. J Virol 65: 3076–3082
Denison MR, Zoltick PW, Hughes SA, Giangreco B, Olson AL, Perlman S, Leibowitz JL, Weiss SR (1992) Intracellular processing of the N-terminal ORF la proteins of the Coronavirus MHV-A59 requires multiple proteolytic events. Virology 189: 274–284
Shaad MC, Stohlman SA, Egbert J, Lum K, Fu K, Wei T, Baric RS (1990) Genetics of mouse hepatitis virus transcription: Identification of cistrons which may function in positive and negative strand RNA synthesis. Virology 177: 634–645
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 1994 Springer-Verlag
About this paper
Cite this paper
Weiss, S.R., Hughes, S.A., Bonilla, P.J., Turner, J.D., Leibowitz, J.L., Denison, M.R. (1994). Coronavirus polyprotein processing. In: Brinton, M.A., Calisher, C.H., Rueckert, R. (eds) Positive-Strand RNA Viruses. Archives of Virology Supplementum, vol 9. Springer, Vienna. https://doi.org/10.1007/978-3-7091-9326-6_35
Download citation
DOI: https://doi.org/10.1007/978-3-7091-9326-6_35
Publisher Name: Springer, Vienna
Print ISBN: 978-3-211-82522-8
Online ISBN: 978-3-7091-9326-6
eBook Packages: Springer Book Archive