Structures of a large prolate virus capsid in unexpanded and expanded states generate insights into the icosahedral virus assembly
Abstract
Virus assembly occurs by repeated association of tiny building blocks, the capsid protein subunits. The assembled structures are highly dynamic and undergo maturation transformations, ultimately generating an infectious virion particle. We describe, at near-atomic resolution, a major "expansion" transformation in a large, prolate, icosahedral virus, the bacteriophage T4. It involves large-scale movements and remodeling of capsid protein domains that lead to extraordinary capsid stability and additional 70% increase in volume. Small changes in capsid subunit interactions lead to profound alterations in capsid size and volume, allowing evolution of viral variants with survival advantages. These basic principles are relevant to all viruses, particularly the herpesviruses that share common structural features and assembly mechanisms with T4.
- Publication:
-
Proceedings of the National Academy of Science
- Pub Date:
- September 2022
- DOI:
- 10.1073/pnas.2203272119
- Bibcode:
- 2022PNAS..11903272F