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Simple and Robust in vivo and in vitro Approach for Studying Virus Assembly
Published on: March 1, 2012
Budding pathway in the templated assembly of viruslike particles
Andrey G Malyutin1, Bogdan Dragnea
1Department of Chemistry, Indiana University , 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States.
The Journal of Physical Chemistry. B
|August 17, 2013
Summary
Researchers discovered a novel viral capsid protein assembly pathway using inorganic nanoparticles. This process, observed via light scattering and cryo-electron tomography, forms virus-like particles (VLPs) through a unique aggregation and budding mechanism.
Area of Science:
- Biophysics
- Structural Biology
- Nanotechnology
Background:
- Viral capsid proteins self-assemble into icosahedral structures.
- Inorganic nanoparticles can serve as templates for biomolecular assembly.
- Understanding virus assembly is crucial for virology and nanotechnology.
Purpose of the Study:
- To elucidate a new pathway for viral capsid protein assembly around inorganic nanoparticles.
- To investigate the mechanism of virus-like particle (VLP) formation using gold nanoparticles and Brome mosaic virus (BMV) capsid protein.
- To characterize the structure and dynamics of protein-nanoparticle complexes.
Main Methods:
- Time-course light scattering and extinction measurements to monitor assembly kinetics.
- Cryo-electron microscopy (cryo-EM) to visualize nanoparticle-protein clusters.
- Cryo-electron tomography (cryo-ET) to determine interparticle distances and shell structure.
Main Results:
- Observed rapid formation of large nanoparticle-protein clusters at low protein concentrations.
- Confirmed the presence of multiparticle clusters using cryo-EM.
- Cryo-ET revealed an average interparticle distance of ~7.5 nm, suggesting protein shell formation and budding.
- Proposed a VLP generation mechanism involving monomer exchange and shell maturation.
Conclusions:
- A novel pathway for VLP formation around inorganic nanoparticles was identified.
- The findings demonstrate the versatility of plant virus capsid protein assembly.
- This mechanism may offer insights into viral assembly in cellular environments (virus factories).
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