Related Experiment Video
Updated: May 19, 2026
08:33
Nucleocapsid Annealing-Mediated Electrophoresis (NAME) Assay Allows the Rapid Identification of HIV-1 Nucleocapsid Inhibitors
Published on: January 19, 2015
MX2 Mediates Collapse of the HIV-1 Capsid
Andrew Goodale1,2, Szu-Wei Huang3, Nathalia Almeida2
1Randall Centre for Cell and Molecular Biophysics, King's College London, London, UK.
Biorxiv : the Preprint Server for Biology
|May 18, 2026
Summary
Myxovirus resistance 2 (MX2) protein disrupts the HIV-1 capsid structure, preventing viral DNA entry into host cells. This structural insight aids in developing new anti-HIV therapies targeting capsid destabilization.
Area of Science:
- Structural Biology
- Virology
- Immunology
Background:
- The human immunodeficiency virus type 1 (HIV-1) capsid (CA) protein forms a cone-shaped lattice, essential for genome encapsulation and nuclear import.
- Myxovirus resistance 2 (MX2) acts as a host restriction factor, inhibiting HIV-1 replication by targeting the viral capsid.
Purpose of the Study:
- To define the minimal region of MX2 responsible for HIV-1 restriction.
- To elucidate the structural mechanism by which MX2 interacts with and destabilizes the HIV-1 capsid.
Main Methods:
- Cryo-electron microscopy (cryo-EM) to determine the structure of MX2 bound to the HIV-1 capsid.
- Biochemical assays to measure capsid destabilization and integrity.
Main Results:
- A minimal MX2 fragment was identified and produced as a functional recombinant protein.
- Cryo-EM revealed a detailed structure of MX2 bound to the capsid tri-hexamer interface, involving extensive electrostatic and hydrophobic interactions.
- MX2 binding induces conformational changes in the capsid lattice, leading to destabilization and fragmentation.
Conclusions:
- MX2 restricts HIV-1 by disrupting the capsid lattice integrity, preventing nuclear import of the viral genome.
- The structural basis of MX2-mediated restriction provides a foundation for designing novel anti-HIV therapeutics that mimic MX2's action.
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