This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Wissink, E. H. J.
Right arrow Articles by Rottier, P. J. M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Wissink, E. H. J.
Right arrow Articles by Rottier, P. J. M.

 Previous Article  |  Next Article 

Journal of Virology, October 2005, p. 12495-12506, Vol. 79, No. 19
0022-538X/05/$08.00+0     doi:10.1128/JVI.79.19.12495-12506.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.

Envelope Protein Requirements for the Assembly of Infectious Virions of Porcine Reproductive and Respiratory Syndrome Virus

E. H. J. Wissink ,1,{dagger},{ddagger} M. V. Kroese,1*,{dagger} H. A. R. van Wijk ,1,§ F. A. M. Rijsewijk,1 J. J. M. Meulenberg,1,¶ and P. J. M. Rottier2

Animal Sciences Group, Wageningen University, Infectious Diseases Division, P.O. Box 65, 8200 AB Lelystad, The Netherlands,1 Virology Division, Utrecht University, P.O. Box 80165, 3508 TD Utrecht, The Netherlands2

Received 27 June 2004/ Accepted 8 July 2005

Virions of porcine reproductive and respiratory syndrome virus (PRRSV) contain six membrane proteins: the major proteins GP5 and M and the minor proteins GP2a, E, GP3, and GP4. Here, we studied the envelope protein requirements for PRRSV particle formation and infectivity using full-length cDNA clones in which the genes encoding the membrane proteins were disrupted by site-directed mutagenesis. By transfection of RNAs transcribed from these cDNAs into BHK-21 cells and analysis of the culture medium using ultracentrifugation, radioimmunoprecipitation, and real-time reverse transcription-PCR, we observed that the production of viral particles is dependent on both major envelope proteins; no particles were released when either the GP5 or the M protein was absent. In contrast, particle production was not dependent on the minor envelope proteins. Remarkably, in the absence of any one of the latter proteins, the incorporation of all other minor envelope proteins was affected, indicating that these proteins interact with each other and are assembled into virions as a multimeric complex. Independent evidence for such complexes was obtained by coexpression of the minor envelope proteins in BHK-21 cells using a Semliki Forest virus expression system. By analyzing the maturation of their N-linked oligosaccharides, we found that the glycoproteins were each retained in the endoplasmic reticulum unless expressed together, in which case they were collectively transported through the Golgi complex to the plasma membrane and were even detected in the extracellular medium. As the PRRSV particles lacking the minor envelope proteins are not infectious, we hypothesize that the virion surface structures formed by these proteins function in viral entry by mediating receptor binding and/or virus-cell fusion.

* Corresponding author. Mailing address: Animal Sciences Group (Wageningen UR), Infectious Diseases Division, Edelhertweg 15, P.O. Box 65, 8200 AB Lelystad, The Netherlands. Phone: 31 320 238349. Fax: 31 320 238225. E-mail: michiel.kroese{at}wur.nl.

{dagger} E.H.J.W. and M.V.K. contributed equally to this work.

{ddagger} Present address: Netherlands Cancer Institute (NKI/AvL), Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands.

§ Present address: Department of Otorhinolaryngology, UMC Nijmegen, Geert Grooteplein 10, 6525 GA Nijmegen, The Netherlands.

Present address: Amsterdam Molecular Therapeutics, Meibergdreef 61, P.O. Box 22506, 1105 DA Amsterdam, The Netherlands.

Journal of Virology, October 2005, p. 12495-12506, Vol. 79, No. 19
0022-538X/05/$08.00+0     doi:10.1128/JVI.79.19.12495-12506.2005
Copyright © 2005, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Spilman, M. S., Welbon, C., Nelson, E., Dokland, T. (2009). Cryo-electron tomography of porcine reproductive and respiratory syndrome virus: organization of the nucleocapsid. J. Gen. Virol. 90: 527-535 [Abstract] [Full Text]  
  • van den Born, E., Posthuma, C. C., Knoops, K., Snijder, E. J. (2007). An infectious recombinant equine arteritis virus expressing green fluorescent protein from its replicase gene. J. Gen. Virol. 88: 1196-1205 [Abstract] [Full Text]  
  • Costers, S., Delputte, P. L., Nauwynck, H. J. (2006). Porcine reproductive and respiratory syndrome virus-infected alveolar macrophages contain no detectable levels of viral proteins in their plasma membrane and are protected against antibody-dependent, complement-mediated cell lysis.. J. Gen. Virol. 87: 2341-2351 [Abstract] [Full Text]  
  • Oostra, M., de Haan, C. A. M., de Groot, R. J., Rottier, P. J. M. (2006). Glycosylation of the Severe Acute Respiratory Syndrome Coronavirus Triple-Spanning Membrane Proteins 3a and M. J. Virol. 80: 2326-2336 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»