Article

Virus Genes

, Volume 10, Issue 2, pp 137-148

First online:

Identification of the membrane protein of porcine epidemic diarrhea virus

  • Anna UtigerAffiliated withInstitute of Virology, Faculty of Veterinary Medicine, University of Zurich
  • , Kurt ToblerAffiliated withInstitute of Virology, Faculty of Veterinary Medicine, University of Zurich
  • , Anne BridgenAffiliated withInstitute of Virology, Faculty of Veterinary Medicine, University of Zurich
  • , Mathias AckermannAffiliated withInstitute of Virology, Faculty of Veterinary Medicine, University of Zurich

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access

Abstract

Sequence information on the genome of porcine epidemic diarrhea virus (PEDV) has only recently been determined. In contrast, very little is known about the viral proteins. In the present report we have identified the membrane glycoprotein (M) of PEDV by use of rabbit anti-peptide sera and transient expression of the cloned M gene in Vero cells and by expression in the baculovirus system. The native M protein of PEDV is incorporated into virions, is N-glycosylated, and migrates with a relative mobility (Mr) of 27 k in polyacrylamide gels. In contrast, the M protein synthesized by recombinant baculoviruses migrates with a Mr of 23 k, that is, with identical mobility as the deglycosylated product of PEDV. Thus, it appears that M protein specified by the recombinant baculovirus is poorly, if at all, glycosylated. Using monoclonal antibodies and rabbit antipeptide sera specific for the N and C termini of the M protein, we were able to show that a 19 k band detected in PEDV-infected cells but not in virions represented a fragment of M from which the C terminus had been cleaved off. Finally, by electron microscopy and immunogold labelling, the relative orientation of M within the virion envelope was determined as NexoCcyt. In conclusion, all of these data strongly support the hypothesis that PEDV should be classified with the group I coronaviruses.

Key words

coronavirus porcine epidemic diarrhea PEDV membrane protein