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Updated: May 18, 2026
12:42
Paramyxoviruses for Tumor-targeted Immunomodulation: Design and Evaluation Ex Vivo
Published on: January 7, 2019
Triggering the measles virus membrane fusion machinery
Melinda A Brindley1, Makoto Takeda, Philippe Plattet
1Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30322, USA.
Summary
Receptor binding to measles virus (MeV) attachment protein (H) triggers fusion protein (F) activation. This process involves structural changes in H, enabling viral infection.
Area of Science:
- Virology
- Structural Biology
- Molecular Biology
Background:
- Paramyxoviruses utilize glycoprotein fusion machinery for cellular entry.
- The precise mechanisms of receptor-induced triggering of this fusion machinery are not fully understood.
Purpose of the Study:
- To elucidate the molecular framework and mechanistic principles of receptor-induced triggering of the measles virus (MeV) fusion machinery.
Main Methods:
- Utilized measles virus (MeV) fusion complexes.
- Investigated the effects of receptor binding, mutations, and soluble ligands on the H protein structure and F protein activation.
Main Results:
- Receptor binding to one dimer of the tetrameric H protein induces F triggering.
- Communication of binding and triggering occurs across the H dimer-dimer interface.
- Structural flexibility in the H ectodomain stalk is crucial for F activation.
- Soluble receptor binding is sufficient to initiate F refolding.
Conclusions:
- A model for MeV fusion machinery triggering is proposed, involving unilateral receptor binding to H.
- Receptor binding induces H reorganization, affecting the stalk region and activating F refolding.
- The physical integrity of the H tetramer is maintained throughout the fusion process.
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