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Co-immunoprecipitation of the Mouse Mx1 Protein with the Influenza A Virus Nucleoprotein
09:39

Co-immunoprecipitation of the Mouse Mx1 Protein with the Influenza A Virus Nucleoprotein

Published on: April 21, 2015

A virulence factor of myxoma virus colocalizes with NF-kappaB in the nucleus and interferes with inflammation

Christelle Camus-Bouclainville1, Laurence Fiette, Sophie Bouchiha

  • 1UMR 1225 Interactions Hôtes Agents Pathogènes, INRA/ENVT, Ecole Nationale Vétérinaire de Toulouse, 31076 Toulouse Cedex, France.

Journal of Virology
|February 14, 2004
PubMed

Insights

Myxoma virus protein MNF (myxoma nuclear factor) is crucial for virulence by interacting with NF-kappaB. Its absence leads to less severe myxomatosis, indicating MNF

Area of Science:

  • Virology
  • Immunology
  • Molecular Biology

Background:

  • Nuclear Factor kappa B (NF-kappaB) regulates immune and inflammatory responses.
  • Myxoma virus, a Poxviridae family member, causes rabbit myxomatosis and possesses factors for host survival.
  • The M150R gene product of myxoma virus was investigated for its role in host-pathogen interactions.

Purpose of the Study:

  • To characterize the M150R gene product, named Myxoma Nuclear Factor (MNF).
  • To determine MNF's role in the host immune response, specifically its interaction with NF-kappaB.
  • To assess MNF's contribution to myxoma virus virulence.

Main Methods:

  • Protein analysis of the M150R gene product, identifying ankyrin repeats (ANKs).
  • Cellular localization studies using immunofluorescence in tumor necrosis factor alpha-treated cells.
  • In vivo virulence assessment using a knockout myxoma virus lacking the M150R gene.
  • Histological examination of infected tissues.

Main Results:

  • MNF contains nine ANKs, with the eighth ANK similar to I-kappaBalpha's nuclear localization signal, mediating nuclear import.
  • MNF and NF-kappaB colocalize in the nucleus of treated cells.
  • M150R knockout virus exhibited significantly reduced virulence, becoming nearly apathogenic.
  • Absence of MNF resulted in an increased inflammatory response, suggesting interference with NF-kappaB pathways.

Conclusions:

  • MNF is a critical virulence factor for myxoma virus, essential for its pathogenic properties.
  • MNF likely modulates the NF-kappaB-mediated inflammatory pathway, contributing to viral pathogenesis.
  • Homologs of MNF in other poxviruses suggest a conserved mechanism for viral immune evasion and virulence.

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