Seeing the portal in herpes simplex virus type 1 B capsids
1Structural Computational Biology and Molecular Biophysics Program, Baylor College of Medicine, Houston, Texas 77030, USA.
Journal of Virology
|November 26, 2010
Summary
Structural virology challenges were overcome using Zernike phase-contrast cryo-electron microscopy to visualize the herpes simplex virus type 1 portal vertex. This study reveals the 12-subunit portal organization, clarifying its location and stoichiometry.
Area of Science:
- Structural biology
- Virology
- Microscopy
Background:
- Large icosahedral viruses present challenges in resolving nonicosahedral components.
- Understanding viral structures is crucial for virology and drug development.
Purpose of the Study:
- To resolve the structure of the unique portal vertex in herpes simplex virus type 1 (HSV-1) capsids.
- To determine the subunit organization, location, and stoichiometry of the HSV-1 portal.
Main Methods:
- Utilized Zernike phase-contrast electron cryomicroscopy for enhanced image contrast.
- Performed image reconstruction to analyze ice-embedded HSV-1 capsids.
Main Results:
- Successfully retrieved the structure of the portal vertex within the icosahedral capsid.
- Unambiguously resolved the 12-subunit portal located beneath a pentameric vertex.
- Provided the first detailed view of portal subunit organization in a eukaryotic virus.
Conclusions:
- Zernike phase-contrast cryo-electron microscopy is effective for visualizing complex viral structures.
- The study clarifies the portal's location and 12-subunit stoichiometry in herpesviruses.
- This work advances structural virology by resolving previously challenging viral components.
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