Rab8b Regulates Transport of West Nile Virus Particles from Recycling Endosomes

J Biol Chem. 2016 Mar 18;291(12):6559-68. doi: 10.1074/jbc.M115.712760. Epub 2016 Jan 27.

Abstract

West Nile virus (WNV) particles assemble at and bud into the endoplasmic reticulum (ER) and are secreted from infected cells through the secretory pathway. However, the host factor related to these steps is not fully understood. Rab proteins, belonging to the Ras superfamily, play essential roles in regulating many aspects of vesicular trafficking. In this study, we sought to determine which Rab proteins are involved in intracellular trafficking of nascent WNV particles. RNAi analysis revealed that Rab8b plays a role in WNV particle release. We found that Rab8 and WNV antigen were colocalized in WNV-infected human neuroblastoma cells, and that WNV infection enhanced Rab8 expression in the cells. In addition, the amount of WNV particles in the supernatant of Rab8b-deficient cells was significantly decreased compared with that of wild-type cells. We also demonstrated that WNV particles accumulated in the recycling endosomes in WNV-infected cells. In summary, these results suggest that Rab8b is involved in trafficking of WNV particles from recycling endosomes to the plasma membrane.

Keywords: Rab; flavivirus; infection; transport; vesicles.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biological Transport
  • Chlorocebus aethiops
  • Endosomes / enzymology*
  • Endosomes / virology
  • Fibroblasts / enzymology
  • Fibroblasts / virology
  • HEK293 Cells
  • Host-Pathogen Interactions
  • Humans
  • Mice
  • Mice, Knockout
  • Protein Transport
  • Transport Vesicles / virology
  • Vero Cells
  • Viral Proteins
  • Virus Release
  • Virus Replication
  • West Nile virus / physiology*
  • rab GTP-Binding Proteins / physiology*

Substances

  • Viral Proteins
  • Rab8b protein, mouse
  • rab GTP-Binding Proteins