The interface between methyltransferase and polymerase of NS5 is essential for flavivirus replication

PLoS Negl Trop Dis. 2014 May 22;8(5):e2891. doi: 10.1371/journal.pntd.0002891. eCollection 2014 May.

Abstract

The flavivirus NS5 harbors both a methyltransferase (MTase) and an RNA-dependent RNA polymerase (RdRP). Both enzyme activities of NS5 are critical for viral replication. Recently, the full-length NS5 crystal structure of Japanese encephalitis virus reveals a conserved MTase-RdRP interface that features two conserved components: a six-residue hydrophobic network and a GTR sequence. Here we showed for the first time that these key interface components are essential for flavivirus replication by various reverse genetics approaches. Interestingly, some replication-impaired variants generated a common compensatory NS5 mutation outside the interface (L322F), providing novel routes to further explore the crosstalk between MTase and RdRP.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Cell Line
  • Conserved Sequence
  • DNA-Directed RNA Polymerases / chemistry*
  • DNA-Directed RNA Polymerases / genetics
  • Flavivirus / genetics*
  • Flavivirus / physiology*
  • Hydrophobic and Hydrophilic Interactions
  • Methyltransferases / chemistry*
  • Methyltransferases / genetics
  • Molecular Sequence Data
  • Sequence Alignment
  • Viral Nonstructural Proteins / chemistry*
  • Viral Nonstructural Proteins / genetics
  • Virus Replication / genetics*

Substances

  • NS5 protein, flavivirus
  • Viral Nonstructural Proteins
  • Methyltransferases
  • DNA-Directed RNA Polymerases

Grants and funding

This work was supported by the National Key Basic Research Program of China (grant Nos. 2011CB5047, 2012CB518904 and 2013CB911101), the National Natural Science Foundation of China (grant Nos. 31170158, 31300151, and 31370198), and the ‘100 Talents Program' of Chinese Academy of Sciences, China. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.