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Updated: Mar 27, 2026
14:55
Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
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Structure determination of helical filaments by solid-state NMR spectroscopy
Lichun He1, Benjamin Bardiaux2, Mumdooh Ahmed3
1Laboratory for Macromolecular Interactions, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany;
Summary
Researchers determined the atomic structure of helical MAVS filaments using solid-state NMR. This breakthrough reveals how these protein filaments form and function in innate immunity signaling.
Area of Science:
- Structural biology
- Immunology
- Biophysics
Background:
- Filamentous protein complexes are vital in biological signaling.
- Mitochondrial antiviral signaling protein (MAVS) forms helical filaments crucial for innate immunity.
- Determining symmetry parameters of helical filaments from ssNMR data is challenging.
Purpose of the Study:
- To solve the atomic resolution structure of helical MAVS(CARD) filaments using ssNMR.
- To develop a general approach for determining helical symmetry parameters from ssNMR data.
- To elucidate the atomic contacts and mechanism of MAVS filament formation.
Main Methods:
- Solid-state NMR (ssNMR) spectroscopy.
- Systematic exploration of helical symmetry space using modeling and interprotomer distance restraints.
- Automated NMR structure calculation.
- Solvent paramagnetic resonance enhancement and mutagenesis for validation.
Main Results:
- Atomic resolution structure of helical MAVS(CARD) filaments determined solely from ssNMR data.
- A novel, generally applicable method for deriving helical symmetry parameters from ssNMR.
- Detailed insights into atomic contacts stabilizing the filaments.
- Mechanistic understanding of signaling-competent MAVS filament assembly.
Conclusions:
- The study successfully determined the structure of helical MAVS filaments using ssNMR, overcoming previous symmetry determination challenges.
- The developed methodology provides a broadly applicable approach for structural analysis of helical protein assemblies.
- The findings offer critical insights into the molecular mechanisms of innate immune signaling via MAVS filament formation.
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