Enterovirus 71 VP1 activates calmodulin-dependent protein kinase II and results in the rearrangement of vimentin in human astrocyte cells

PLoS One. 2013 Sep 20;8(9):e73900. doi: 10.1371/journal.pone.0073900. eCollection 2013.

Abstract

Enterovirus 71 (EV71) is one of the main causative agents of foot, hand and mouth disease. Its infection usually causes severe central nervous system diseases and complications in infected infants and young children. In the present study, we demonstrated that EV71 infection caused the rearrangement of vimentin in human astrocytoma cells. The rearranged vimentin, together with various EV71 components, formed aggresomes-like structures in the perinuclear region. Electron microscopy and viral RNA labeling indicated that the aggresomes were virus replication sites since most of the EV71 particles and the newly synthesized viral RNA were concentrated here. Further analysis revealed that the vimentin in the virus factories was serine-82 phosphorylated. More importantly, EV71 VP1 protein is responsible for the activation of calmodulin-dependent protein kinase II (CaMK-II) which phosphorylated the N-terminal domain of vimentin on serine 82. Phosphorylation of vimentin and the formation of aggresomes were required for the replication of EV71 since the latter was decreased markedly after phosphorylation was blocked by KN93, a CaMK-II inhibitor. Thus, as one of the consequences of CaMK-II activation, vimentin phosphorylation and rearrangement may support virus replication by playing a structural role for the formation of the replication factories. Collectively, this study identified the replication centers of EV71 in human astrocyte cells. This may help us understand the replication mechanism and pathogenesis of EV71 in human.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Astrocytes / metabolism*
  • Astrocytes / pathology
  • Astrocytes / virology
  • Blotting, Western
  • Calcium-Calmodulin-Dependent Protein Kinase Type 2 / metabolism*
  • Capsid Proteins / genetics
  • Capsid Proteins / metabolism*
  • Cells, Cultured
  • Enterovirus A, Human
  • Enzyme Activation
  • Fluorescent Antibody Technique
  • Gene Rearrangement*
  • Hand, Foot and Mouth Disease / metabolism
  • Hand, Foot and Mouth Disease / pathology
  • Hand, Foot and Mouth Disease / virology*
  • Humans
  • Immunoprecipitation
  • In Situ Hybridization, Fluorescence
  • Phosphorylation
  • RNA, Messenger / genetics
  • Real-Time Polymerase Chain Reaction
  • Reverse Transcriptase Polymerase Chain Reaction
  • Vimentin / genetics*
  • Virus Replication

Substances

  • Capsid Proteins
  • RNA, Messenger
  • VP1 protein, Foot-and-mouth disease virus
  • Vimentin
  • Calcium-Calmodulin-Dependent Protein Kinase Type 2

Grants and funding

This work is supported by the grants from the National Basic Research Program of China (973 Program, Nos. 2011CB504703 and 2010CB530102) and the National Natural Science Foundation of China (NSFC, Grant Nos. 81021003 and 31270211). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.