Alanine substitution of conserved residues in the cytoplasmic tail of herpes simplex virus gB can enhance or abolish cell fusion activity and viral entry

Virology. 2006 Mar 1;346(1):229-37. doi: 10.1016/j.virol.2005.11.002. Epub 2005 Dec 2.


Herpes simplex virus (HSV) glycoprotein B (gB) is one of the four viral glycoproteins required for viral entry and cell fusion and is highly conserved among herpesviruses. Mutants of HSV type 2 gB were generated by substituting conserved residues in the cytoplasmic tail with alanine or by deleting 41 amino acids from the C-terminus. Some of the mutations abolished cell fusion activity and also prevented transport of gB to the cell surface, identifying residues in the gB cytoplasmic tail that are critical for intracellular transport of this glycoprotein. These mutations also prevented production of infectious virus, possibly because the mutant forms of gB were not transported to the site of envelopment. Other mutations, particularly the deletion, significantly enhanced cell fusion activity. These mutations, as well as others described previously, identify regions of the gB cytoplasmic domain that modulate cell fusion activity.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Alanine / chemistry*
  • Amino Acid Sequence
  • Amino Acid Substitution*
  • Animals
  • CHO Cells
  • Cell Fusion
  • Cell Line
  • Conserved Sequence
  • Cricetinae
  • HeLa Cells
  • Humans
  • Membrane Fusion / physiology*
  • Molecular Sequence Data
  • Mutation
  • Simplexvirus / metabolism
  • Simplexvirus / pathogenicity*
  • Viral Envelope Proteins / chemistry
  • Viral Envelope Proteins / genetics*
  • Viral Envelope Proteins / metabolism


  • Viral Envelope Proteins
  • glycoprotein B, Simplexvirus
  • Alanine