Seeing the herpesvirus capsid at 8.5 A.

Area of Science:

• Structural biology
• Virology
• Molecular biology

Background:

• Human herpesviruses are large, complex viruses responsible for numerous diseases.
• Understanding their structure is key to developing antiviral strategies.

Purpose of the Study:

• To determine the high-resolution three-dimensional structure of the herpesvirus capsid.
• To identify structural components and their roles in viral assembly and function.

Main Methods:

• Electron cryomicroscopy was used to resolve the capsid structure at 8.5 angstrom resolution.
• Bioinformatic analysis was employed to identify protein components and structural motifs.

Main Results:

• The 0.2 billion-dalton capsid shell is composed of at least four distinct proteins.
• Over 30 alpha helices were identified, with some located in domains undergoing conformational changes.
• The arrangement of heterotrimers at threefold positions dictates asymmetric interactions and subunit folding.

Conclusions:

• The determined structure provides unprecedented insight into herpesvirus capsid architecture.
• Specific alpha helices and their conformational flexibility are critical for capsid assembly and DNA packaging.
• The findings elucidate the molecular mechanisms underlying herpesvirus structural organization and assembly.