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Conformational triggers associated with influenza matrix protein 1 polymerization
Faiz Mohd-Kipli1, Jolyon K Claridge2, Jelena Habjanič2
1Department of Biochemistry, University of Oxford, Oxford, United Kingdom; Faculty of Science, Universiti Brunei Darussalam, Gadong, Brunei Darussalam.
The Journal of Biological Chemistry
|January 31, 2021
Summary
Influenza matrix protein 1 (M1) N-terminal domain (M1NT) undergoes pH-dependent polymerization. Sterols, possibly by altering water activity, prime M1NT for polymerization at the host cell membrane surface.
Area of Science:
- Virology
- Structural Biology
- Biochemistry
Background:
- Influenza matrix protein 1 (M1) forms a structural coat essential for virion integrity.
- The triggers for M1 polymerization at the host cell membrane remain unclear.
- The M1 N-terminal domain (M1NT) retains membrane binding and pH-dependent oligomerization capabilities.
Purpose of the Study:
- To investigate the structural plasticity and oligomerization of the M1 N-terminal domain (M1NT).
- To elucidate the role of sterols and pH in M1NT conformational changes and self-association.
Main Methods:
- Nuclear Magnetic Resonance (NMR) spectroscopy was employed to study M1NT in solution.
- Analysis of chemical shift perturbations to identify conformational changes and interaction interfaces.
- Structural modeling to understand the transmission of conformational changes.
Main Results:
- Sterol-containing compounds induced pH-dependent conformational changes and self-association of M1NT.
- Sterol effects appear indirect, mediated by reduced water activity, priming M1NT for polymerization.
- Perturbed residues are conserved and located at subdomain interfaces, sensitive to both sterols and pH.
Conclusions:
- M1NT is sensitive to changes in the aqueous environment, suggesting a mechanism for localized polymerization.
- Sterol-mediated priming of M1NT may restrict polymerization to the membrane surface.
- Conformational changes in M1NT are transmitted between polymerization interfaces, influencing viral assembly.
Keywords:
allosteric regulationcholesterolconformational changeinfluenza virusmatrix protein 1membranenuclear magnetic resonance (NMR)sterolstructure–functionMore Related Videos
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