Analysis of contributions of herpes simplex virus type 1 UL43 protein to induction of cell-cell fusion

  • Zhaobing Liu
  • Junli Huang
  • Qing Ding
  • Yan Yang
  • Hanxiao Sun
Keywords: Herpes simplex virus type 1, UL43 protein, Membrane fusion, Mutant viruses, Virion, Mutagenesis

Abstract

Purpose: To investigate whether UL43 protein, which is highly conserved in alpha- and gamma herpes viruses, and a non-glycosylated transmembrane protein, is involved in virus entry and virus-induced cell fusion.
Methods: Mutagenesis was accomplished by a markerless two-step Red  recombination mutagenesis system implemented on the Herpes simplex virus 1 (HSV-1) bacterial artificial chromosome (BAC). Growth properties of HSV-1 UL43 mutants were analyzed using plaque morphology and one-step growth kinetics. SDS-PAGE and Western blot was employed to assay the synthesis of the viral glycoproteins. Virus-penetration was assayed to determine if UL43 protein is required for efficient virus entry.
Results: Lack of UL43 expression resulted in significantly reduced plaque sizes of syncytial mutant viruses and inhibited cell fusion induced by gBΔ28 or gKsyn20 (p < 0.05). Deletion of UL43 did not affect overall expression levels of viral  glycoproteins gB, gC, gD, and gH on HSV-1(F) BAC infected cell surfaces.  Moreover, mutant viruses lacking UL43 gene exhibited slower kinetics of entry into Vero cells than the parental HSV-1(F) BAC.
Conclusion: Thus, these results suggest an important role for UL43 protein in  mediating virus-induced membrane fusion and efficient entry of virion into target cells.

Keywords: Herpes simplex virus type 1, UL43 protein, Membrane fusion, Mutant viruses, Virion, Mutagenesis

Published
2016-07-08
Section
Articles

Journal Identifiers


eISSN: 1596-9827
print ISSN: 1596-5996