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Updated: Oct 21, 2025
Co-immunoprecipitation of the Mouse Mx1 Protein with the Influenza A Virus Nucleoprotein
Published on: April 21, 2015
[Wide range antiviral activity of MxA protein]
1Laboratoire mixte Inserm U370, Institut Pasteur, Carcinogenèse hépatique et virologie cellulaire, 156, rue de Vaugirard, 75730 Paris Cedex 15.
Abstract:
Mx proteins are interferon-induced GTPases belonging to the dynamin superfamily of large GTPases.A unique property of Mx GTPases is their antiviral activity against a wide range of RNA viruses, including bunya-and orthomyxoviruses. The human MxA GTPase accumulates in the cytoplasm of interferon-treated cells, partly associating with the endoplasmic reticulum. In the cases of Thogoto and La Cross viruses, MxA appears to detect viral infection by sensing nucleocapsid-like structures. Indeed, MxA interacts directly with the viral nucleocapsid protein of these viruses. As a consequence, these viral components are trapped and sorted to locations where they become unavailable for the generation of new virus particles. In both cases, the GTP-binding and carboxy-terminal effector functions of MxA are required for target recognition. Moreover, human MxA possesses many biophysical properties of traditional dynamin and may act to inhibit viral replication through alterations in membrane organization or viral trafficking. This hypothesis still needs to be demonstrated.
Insights
Mx proteins are interferon-induced GTPases with antiviral properties. Human MxA GTPase inhibits viral replication by trapping viral components, potentially by altering membrane organization.
Area of Science:
- Biochemistry
- Virology
- Cell Biology
Context:
- Mx proteins are interferon-induced GTPases with antiviral functions.
- Human MxA GTPase is involved in defense against RNA viruses like bunya- and orthomyxoviruses.
Purpose:
- To investigate the antiviral mechanism of human MxA GTPase against specific RNA viruses.
- To understand how MxA GTPase interacts with viral components and affects viral replication.
Summary:
- Human MxA GTPase accumulates in interferon-treated cells and interacts with viral nucleocapsid proteins of Thogoto and La Cross viruses.
- This interaction traps viral components, preventing new virus particle generation. Both GTP-binding and effector functions of MxA are crucial for this process.
- MxA shares biophysical properties with dynamin, suggesting a potential role in inhibiting viral replication via membrane organization or trafficking alterations.
Impact:
- Provides insights into the molecular mechanisms of innate antiviral immunity.
- Highlights the role of Mx proteins as key effectors in the interferon response.
- Suggests potential therapeutic strategies targeting viral trafficking and membrane organization.
