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In Vitro Disassembly of Influenza A Virus Capsids by Gradient Centrifugation
07:24

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The influenza A virus M2 cytoplasmic tail is required for infectious virus production and efficient genome packaging

Matthew F McCown1, Andrew Pekosz

  • 1Department of Molecular Microbiology, Washington University School of Medicine, Campus Box 8230, 660 S. Euclid Ave., St. Louis, MO 63110-1093, USA.

Journal of Virology
|February 26, 2005
PubMed

Insights

The influenza A virus M2 protein

Area of Science:

  • Virology
  • Molecular Biology
  • Cell Biology

Background:

  • Influenza A virus M2 protein is an ion channel crucial for virus entry.
  • The function of the M2 protein's cytoplasmic tail in viral replication is not fully understood.

Purpose of the Study:

  • To investigate the role of the M2 protein cytoplasmic tail in influenza A virus replication.
  • To determine how truncations in the M2 protein's C-terminus affect virus production and infectivity.

Main Methods:

  • Generation of influenza A viruses with truncated M2 C-termini (M2Stop70).
  • Analysis of viral particle production, infectivity, morphology, and content (nucleoprotein and genomic RNA).
  • Complementation experiments expressing full-length M2 protein in trans.

Main Results:

  • Truncation of the M2 cytoplasmic tail (M2Stop70) significantly reduced infectious virus production (>1,000-fold).
  • M2Stop70 virus particles showed defects in packaging viral nucleoprotein and genomic RNA.
  • Restoration of full-length M2 expression rescued viral replication.

Conclusions:

  • The M2 protein cytoplasmic tail is essential for efficient infectious influenza A virus production.
  • The M2 cytoplasmic tail plays a critical role in coordinating the packaging of viral genome segments into new virions.

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