Dual modes of rabies P-protein association with microtubules: a novel strategy to suppress the antiviral response

J Cell Sci. 2009 Oct 15;122(Pt 20):3652-62. doi: 10.1242/jcs.045542. Epub 2009 Sep 22.

Abstract

Conventional nuclear import is independent of the cytoskeleton, but recent data have shown that the import of specific proteins can be either facilitated or inhibited by microtubules (MTs). Nuclear import of the P-protein from rabies virus involves a MT-facilitated mechanism, but here, we show that P-protein is unique in that it also undergoes MT-inhibited import, with the mode of MT-interaction being regulated by the oligomeric state of the P-protein. This is the first demonstration that a protein can utilise both MT-inhibited and MT-facilitated import mechanisms, and can switch between these different modes of MT interaction to regulate its nuclear trafficking. Importantly, we show that the P-protein exploits MT-dependent mechanisms to manipulate host cell processes by switching the import of the interferon-activated transcription factor STAT1 from a conventional to a MT-inhibited mechanism. This prevents STAT1 nuclear import and signalling in response to interferon, which is vital to the host innate antiviral response. This is the first report of MT involvement in the viral subversion of interferon signalling that is central to virus pathogenicity, and identifies novel targets for the development of antiviral drugs or attenuated viruses for vaccine applications.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Active Transport, Cell Nucleus / drug effects
  • Animals
  • Antiviral Agents / metabolism*
  • Cell Line
  • Cell Nucleus / drug effects
  • Cell Nucleus / metabolism
  • Dynactin Complex
  • Green Fluorescent Proteins / metabolism
  • Humans
  • Interferons / pharmacology
  • Microtubule-Associated Proteins / metabolism
  • Microtubules / drug effects
  • Microtubules / metabolism*
  • Models, Biological
  • Molecular Chaperones
  • Phosphoproteins / chemistry
  • Phosphoproteins / metabolism*
  • Protein Binding / drug effects
  • Protein Multimerization / drug effects
  • Protein Structure, Tertiary
  • Rabies / metabolism
  • Rabies / virology*
  • Recombinant Fusion Proteins / metabolism
  • STAT1 Transcription Factor / metabolism
  • Signal Transduction / drug effects
  • Viral Structural Proteins / chemistry
  • Viral Structural Proteins / metabolism*

Substances

  • Antiviral Agents
  • Dynactin Complex
  • Microtubule-Associated Proteins
  • Molecular Chaperones
  • P phosphoprotein, Rabies virus
  • Phosphoproteins
  • Recombinant Fusion Proteins
  • STAT1 Transcription Factor
  • Viral Structural Proteins
  • Green Fluorescent Proteins
  • Interferons