Absence of E protein arrests transmissible gastroenteritis coronavirus maturation in the secretory pathway

Virology. 2007 Nov 25;368(2):296-308. doi: 10.1016/j.virol.2007.05.032. Epub 2007 Aug 10.


A recombinant transmissible gastroenteritis coronavirus (rTGEV) in which E gene was deleted (rTGEV-DeltaE) has been engineered. This deletion mutant only grows in cells expressing E protein (E(+) cells) indicating that E was an essential gene for TGEV replication. Electron microscopy studies of rTGEV-DeltaE infected BHK-pAPN-E(-) cells showed that only immature intracellular virions were assembled. These virions were non-infectious and not secreted to the extracellular medium in BHK-pAPN-E(-) cells. RNA and protein composition analysis by RNase-gold and immunoelectron microscopy showed that rTGEV-DeltaE virions contained RNA and also all the structural TGEV proteins, except the deleted E protein. Nevertheless, full virion maturation was blocked. Studies of the rTGEV-DeltaE subcellular localization by confocal and immunoelectron microscopy in infected E(-) cells showed that in the absence of E protein virus trafficking was arrested in the intermediate compartment. Therefore, the absence of E protein in TGEV resulted in two actions, a blockade of virus trafficking in the membranes of the secretory pathway, and prevention of full virus maturation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line
  • Cricetinae
  • Gene Deletion*
  • Genes, Essential*
  • LLC-PK1 Cells / virology
  • Swine
  • Transmissible gastroenteritis virus / genetics
  • Transmissible gastroenteritis virus / growth & development*
  • Transmissible gastroenteritis virus / metabolism
  • Transmissible gastroenteritis virus / physiology*
  • Viral Envelope Proteins / genetics*
  • Viral Envelope Proteins / metabolism
  • Viral Proteins / genetics
  • Viral Proteins / metabolism
  • Virion / growth & development
  • Virion / metabolism
  • Virus Replication


  • Viral Envelope Proteins
  • Viral Proteins