The Host Protein Reticulon 3.1A Is Utilized by Flaviviruses to Facilitate Membrane Remodelling

Cell Rep. 2017 Nov 7;21(6):1639-1654. doi: 10.1016/j.celrep.2017.10.055.

Abstract

Flaviviruses are enveloped, positive-sensed single-stranded RNA viruses that remodel host membranes, incorporating both viral and host factors facilitating viral replication. In this study, we identified a key role for the membrane-bending host protein Reticulon 3.1 (RTN3.1A) during the replication cycle of three flaviviruses: West Nile virus (WNV), Dengue virus (DENV), and Zika virus (ZIKV). We observed that, during infection, RTN3.1A is redistributed and recruited to the viral replication complex, a recruitment facilitated via the WNV NS4A protein, however, not DENV or ZIKV NS4A. Critically, small interfering RNA (siRNA)-mediated knockdown of RTN3.1A expression attenuated WNV, DENV, and ZIKV replication and severely affected the stability and abundance of the NS4A protein, coinciding with a significant alternation and reduction of viral membrane structures in the endoplasmic reticulum. These observations identified a crucial role of RTN3.1A for the viral remodelling of host membranes during efficient flavivirus replication and the stabilization of viral proteins within the endoplasmic reticulum.

Keywords: Dengue virus; NS4A; West Nile virus; Zika virus; flavivirus; host-virus interaction; membrane; reticulon; virus replication.

MeSH terms

  • Carrier Proteins / antagonists & inhibitors
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Dengue Virus / physiology*
  • Endoplasmic Reticulum / chemistry
  • Endoplasmic Reticulum / metabolism
  • HEK293 Cells
  • HeLa Cells
  • Humans
  • Leupeptins / pharmacology
  • Membrane Proteins / antagonists & inhibitors
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Microscopy, Electron
  • Microscopy, Fluorescence
  • Nerve Tissue Proteins / antagonists & inhibitors
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism*
  • Proteasome Endopeptidase Complex / chemistry
  • Proteasome Endopeptidase Complex / metabolism
  • RNA Interference
  • RNA, Small Interfering / metabolism
  • Viral Nonstructural Proteins / chemistry
  • Viral Nonstructural Proteins / metabolism
  • Virus Replication / drug effects
  • West Nile virus / physiology*
  • Zika Virus / physiology*

Substances

  • Carrier Proteins
  • Leupeptins
  • Membrane Proteins
  • NS4A protein, flavivirus
  • Nerve Tissue Proteins
  • RNA, Small Interfering
  • RTN3 protein, human
  • Viral Nonstructural Proteins
  • Proteasome Endopeptidase Complex
  • benzyloxycarbonylleucyl-leucyl-leucine aldehyde