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Updated: Aug 22, 2026

Characterization of Multi-subunit Protein Complexes of Human MxA Using Non-denaturing Polyacrylamide Gel-electrophoresis
08:55

Characterization of Multi-subunit Protein Complexes of Human MxA Using Non-denaturing Polyacrylamide Gel-electrophoresis

Published on: October 28, 2016

Missorting of LaCrosse virus nucleocapsid protein by the interferon-induced MxA GTPase involves smooth ER membranes

Mike Reichelt1, Silke Stertz, Jacomine Krijnse-Locker

  • 1Abteilung Virologie, Institut für Medizinische Mikrobiologie und Hygiene, Universität Freiburg, D-79008 Freiburg, Germany.

Traffic (Copenhagen, Denmark)
|September 10, 2004
PubMed

Insights

The MxA protein, an antiviral defense, disrupts RNA virus replication by binding viral nucleocapsid proteins. It sequesters these essential viral components within membrane-associated complexes, preventing viral spread.

Area of Science:

  • Virology
  • Cell Biology
  • Immunology

Background:

  • The interferon-induced human MxA protein is a large GTPase involved in vesicle trafficking and organelle homeostasis.
  • MxA shares self-assembly and membrane-association properties with dynamin-like GTPases.
  • MxA exhibits unique antiviral activity against various RNA viruses.

Purpose of the Study:

  • To investigate the role of cellular membranes in the antiviral function of MxA.
  • To elucidate the mechanism by which MxA inhibits LaCrosse-bunyavirus (LACV) replication.

Main Methods:

  • Utilized MxA-expressing cells and LACV infection models.
  • Investigated viral glycoprotein trafficking and sorting.
  • Analyzed the localization and complex formation of MxA and the viral nucleocapsid (N) protein using microscopy and biochemical techniques.

Main Results:

  • MxA does not impede viral glycoprotein trafficking.
  • MxA binds and mislocalizes the viral nucleocapsid (N) protein into perinuclear complexes associated with membranes.
  • MxA localizes to a smooth endoplasmic reticulum subcompartment where viral N protein accumulates.
  • Oligomeric MxA/N complexes form near COP-I-positive vesicular-tubular membranes in infected cells.

Conclusions:

  • Cellular membranes, specifically a smooth endoplasmic reticulum subcompartment, serve as a critical site for MxA-N protein interaction.
  • MxA's antiviral mechanism involves sequestering and missorting the viral nucleocapsid protein within membrane-associated complexes.
  • This membrane-dependent sequestration effectively inhibits viral replication by targeting an essential viral component.

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