A single mutation in the Japanese encephalitis virus E protein (S123R) increases its growth rate in mouse neuroblastoma cells and its pathogenicity in mice

作者：Tajima Shigeru^*; Nerome Reiko; Nukui Yoko; Kato Fumihiro; Takasaki Tomohiko; Kurane Ichiro

来源：Virology, 2010, 396(2): 298-304.

DOI：10.1016/j.virol.2009.10.035

• Japanese encephalitis virus
• Infections clone
• E protein
• Pathogenesis

We previously reported that the Japanese encephalitis virus (JEV) strain Mie/41/2002 has weak pathogenicity compared with the laboratory strain Beijing-1. To identify the determinants of its growth nature and pathogenicity, we produced intertypic viruses, rJEV(EBI-M41), rJEV(nEB1-M41) and rJEV(cEB1-M41), which contained the entire, the N-terminal, and the C-terminal half, respectively, of the Beijing-1 E region in the Mie/41/2002 background. The growth of rJEV(EB1-M41) in mouse neuroblastoma N18 cells and virulence in mice were similar to those of Beijing-1. rJEV(nEB1-M41) propagated in N18 cells to the same extent as did Beijing-1. Furthermore. we produced mutant viruses with single amino acid substitutions in the N-terminal half of the Mie/41/2002 E region. A Ser-123-Arg mutation in the Mie/41/2002 E Protein exhibited significantly increased growth rate in N18 cells and Virulence in mice. These results indicate that the position 123 in the E protein is responsible for determining the growth Properties and pathogenicity of JEV.

• 出版日期2010-1-20