Analyses of mutations selected by passaging a chimeric flavivirus identify mutations that alter infectivity and reveal an interaction between the structural proteins and the nonstructural glycoprotein NS1

Evandro R. Winkelmann, Douglas G. Widman, Ryosuke Suzuki, Peter W. Mason

Research output: Contribution to journalArticle

15 Scopus citations


We previously described a single-cycle dengue vaccine (RepliVAX D2) engineered from a capsid (C) gene-deleted West Nile virus (WNV) expressing dengue virus serotype 2 (DENV2) prM/E genes in place of the corresponding WNV genes. That work demonstrated that adaptation of RepliVAX D2 to grow in WNV C-expressing cells resulted in acquisition of non-synonymous mutations in the DENV2 prM/E and WNV NS2A/NS3 genes. Here we demonstrate that the prM/E mutations increase the specific infectivity of chimeric virions and the NS2A/NS3 mutations independently enhance packaging. Studies with the NS2A mutant demonstrated that it was unable to produce a larger form of NS1 (NS1'), suggesting that the mutation had been selected to eliminate a ribosomal frame-shift "slippage site" in NS2A. Evaluation of a synonymous mutation at this slippage site confirmed that genomes that failed to make NS1' were packaged more efficiently than WT genomes supporting a role for NS1/NS1' in orchestrating virion assembly.

Original languageEnglish (US)
Pages (from-to)96-104
Number of pages9
Issue number2
StatePublished - Dec 20 2011



  • Chimera
  • Flavivirus
  • Packaging
  • RepliVAX
  • Single-cycle virus

ASJC Scopus subject areas

  • Virology

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