Self-assembly of model proteins into virus capsids

Area of Science:

• Biophysics
• Computational Biology
• Structural Biology

Background:

• Virus capsid self-assembly is crucial for viral replication and is a complex process.
• Previous models often treated capsomeres as rigid units with artificial interactions.
• Understanding the dynamics of protein self-assembly is key to designing novel nanomaterials and antiviral strategies.

Purpose of the Study:

• To investigate the self-assembly of virus-like protein shells using molecular dynamics.
• To explore the influence of RNA presence and confinement on capsid restoration.
• To model flexible protein behavior with electrostatic interactions.

Main Methods:

• Structure-based coarse-grained molecular dynamics simulations.
• Simulating Small Mottled Stunt Virus (SPSMV) and Cowpea Chlorotic Mottle Virus (CCMV) capsids.
• Inducing dissociation via high temperature and observing self-assembly upon cooling.

Main Results:

• Capsid self-assembly was achieved but rarely reached completion.
• The extent of restoration depended on the initial dissociated state and protein proximity.
• Confinement significantly improved the completeness of capsid restoration.

Conclusions:

• Protein flexibility and electrostatic interactions play vital roles in virus capsid self-assembly.
• The spatial arrangement and proximity of dissociated proteins are critical for successful assembly.
• Confinement is essential for efficient and complete restoration of viral capsids in silico.