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 Wieringa, R.
Right arrow Articles by Rottier, P. J. M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Wieringa, R.
Right arrow Articles by Rottier, P. J. M.

 Previous Article  |  Next Article 

Journal of Virology, June 2003, p. 6216-6226, Vol. 77, No. 11
0022-538X/03/$08.00+0     DOI: 10.1128/JVI.77.11.6216-6226.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.

Formation of Disulfide-Linked Complexes between the Three Minor Envelope Glycoproteins (GP2b, GP3, and GP4) of Equine Arteritis Virus

Roeland Wieringa,* Antoine A. F. de Vries,{dagger} and Peter J. M. Rottier*

Virology Division, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, and Institute of Biomembranes, Utrecht University, 3584 CL Utrecht, The Netherlands

Received 30 October 2002/ Accepted 5 March 2003

Equine arteritis virus (EAV) is an enveloped, positive-stranded RNA virus belonging to the family Arteriviridae of the order Nidovirales. Six transmembrane proteins have been identified in EAV particles: the nonglycosylated membrane protein M and the glycoprotein GP5 (previously named GL), which occur as disulfide-bonded heterodimers and are the major viral envelope proteins; the unglycosylated small envelope protein E; and the minor glycoproteins GP2b (formerly designated GS), GP3, and GP4. Analysis of the appearance of the GP2b, GP3, and GP4 proteins in viral particles by gel electrophoresis under reducing and nonreducing conditions revealed the occurrence of two different covalently linked oligomeric complexes between these proteins, i.e., heterodimers of GP2b and GP4 and heterotrimers of GP2b, GP3, and GP4. Shortly after their release from infected cells, virions contained mainly cystine-linked GP2b/GP4 heterodimers, which were subsequently converted into disulfide-bonded GP2b/GP3/GP4 trimers through the covalent recruitment of GP3. This process occurred faster at a higher pH but was arrested at 4°C. Furthermore, the conversion was almost instantaneous in the presence of the thiol oxidant diamide. In contrast, the sulfhydryl-modifying agent N-ethylmaleimide inhibited the formation of disulfide-bonded GP2b/GP3/GP4 trimers. Using sucrose density gradients, we could not demonstrate a noncovalent association of GP3 with the cystine-linked GP2b/GP4 dimer in freshly released virions, nor did we observe higher-order structures of the GP2b/GP4 or GP2b/GP3/GP4 complexes. Nevertheless, the instantaneous diamide-induced formation of disulfide-bonded GP2b/GP3/GP4 heterotrimers at 4°C suggests that the three minor glycoproteins of EAV are assembled as trimeric complexes. The existence of a noncovalent interaction between the cystine-linked GP2b/GP4 dimer and GP3 was also inferred from coexpression experiments showing that the presence of GP3 increased the electrophoretic mobility of the disulfide-bonded GP2b/GP4 dimers. Our study reveals that the minor envelope proteins of arteriviruses enter into both covalent and noncovalent interactions, the function of which has yet to be established.

* Corresponding author. Mailing address: Virology Division, Department of Infectious Diseases and Immunology, Yalelaan 1, 3584 CL Utrecht, The Netherlands. Phone: 31-30-2532463. Fax: 31-30-2536723. E-mail for Roeland Wieringa: r.wieringa{at}vet.uu.nl. E-mail for Peter J. M. Rottier: p.rottier{at}vet.uu.nl.

{dagger} Present address: Gene Therapy Section, Department of Molecular Cell Biology, Leiden University Medical Center (LUMC), 2333 AL Leiden, The Netherlands.

Journal of Virology, June 2003, p. 6216-6226, Vol. 77, No. 11
0022-538X/03/$08.00+0     DOI: 10.1128/JVI.77.11.6216-6226.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Thaa, B., Kabatek, A., Zevenhoven-Dobbe, J. C., Snijder, E. J., Herrmann, A., Veit, M. (2009). Myristoylation of the arterivirus E protein: the fatty acid modification is not essential for membrane association but contributes significantly to virus infectivity. J. Gen. Virol. 90: 2704-2712 [Abstract] [Full Text]  
  • Lee, C., Yoo, D. (2005). Cysteine residues of the porcine reproductive and respiratory syndrome virus small envelope protein are non-essential for virus infectivity. J. Gen. Virol. 86: 3091-3096 [Abstract] [Full Text]  
  • Wissink, E. H. J., Kroese, M. V., van Wijk, H. A. R., Rijsewijk, F. A. M., Meulenberg, J. J. M., Rottier, P. J. M. (2005). Envelope Protein Requirements for the Assembly of Infectious Virions of Porcine Reproductive and Respiratory Syndrome Virus. J. Virol. 79: 12495-12506 [Abstract] [Full Text]  
  • Wissink, E. H. J., Kroese, M. V., Maneschijn-Bonsing, J. G., Meulenberg, J. J. M., van Rijn, P. A., Rijsewijk, F. A. M., Rottier, P. J. M. (2004). Significance of the oligosaccharides of the porcine reproductive and respiratory syndrome virus glycoproteins GP2a and GP5 for infectious virus production. J. Gen. Virol. 85: 3715-3723 [Abstract] [Full Text]  
  • Wieringa, R., de Vries, A. A. F., van der Meulen, J., Godeke, G.-J., Onderwater, J. J. M., van Tol, H., Koerten, H. K., Mommaas, A. M., Snijder, E. J., Rottier, P. J. M. (2004). Structural Protein Requirements in Equine Arteritis Virus Assembly. J. Virol. 78: 13019-13027 [Abstract] [Full Text]  
  • Wieringa, R., de Vries, A. A. F., Post, S. M., Rottier, P. J. M. (2003). Intra- and Intermolecular Disulfide Bonds of the GP2b Glycoprotein of Equine Arteritis Virus: Relevance for Virus Assembly and Infectivity. J. Virol. 77: 12996-13004 [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»