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A High-throughput Cre-Lox Activated Viral Membrane Fusion Assay to Identify Inhibitors of HIV-1 Viral Membrane Fusion
Published on: August 14, 2018
Class III viral membrane fusion proteins.
Marija Backovic1, Theodore S Jardetzky
1Department of Virology, Pasteur Institute, 75015, Paris, France. marija@pasteur.fr
Advances in Experimental Medicine and Biology
|April 21, 2011
Summary
Class III viral fusion proteins, like herpesvirus glycoprotein B, share structural similarities despite evolutionary distance. Their architecture facilitates viral and cellular membrane fusion, crucial for infection.
Area of Science:
- Structural biology
- Virology
- Molecular biology
Background:
- Class III viral fusion proteins exhibit conserved architecture despite lacking sequence homology across diverse viruses.
- Examples include glycoprotein B (gB) of herpesviruses, G protein of rhabdoviruses, and gp64 of baculoviruses.
Purpose of the Study:
- To analyze the structural features of class III viral fusion proteins.
- To understand the molecular mechanisms underlying viral-cellular membrane fusion.
Main Methods:
- Analysis of experimentally determined three-dimensional structures of viral fusion protein ectodomains.
- Comparison of structures representing post-fusion conformations.
Main Results:
- Class III fusion proteins form trimeric, elongated structures with five domains per protomer.
- Fusion peptides, responsible for membrane interaction, are located in specific loops.
- G protein structures provide insights into pre- and post-fusion conformational changes.
Conclusions:
- The conserved structural organization suggests a potentially common mechanism for membrane fusion among class III viral proteins.
- Further investigation is needed to confirm if this structural similarity translates to a unified fusion mechanism.
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