Subassemblies and asymmetry in assembly of herpes simplex virus procapsid.
Anastasia A AksyukWilliam W NewcombNaiqian ChengDennis C WinklerJuan FontanaJ Bernard HeymannAlasdair C StevenPublished in: mBio (2015)
This paper addresses the molecular mechanisms that govern the self-assembly of large, structurally complex, macromolecular particles, such as the capsids of double-stranded DNA viruses. Although they may consist of thousands of protein subunits of many different kinds, their assembly is precise, ranking them among the largest entities in the biosphere whose structures are uniquely defined to the atomic level. Assembly proceeds in two stages: formation of a precursor particle (procapsid) and maturation, during which major changes in structure and composition take place. Our analysis of the HSV procapsid by cryo-electron microscopy suggests a hierarchical pathway in which multisubunit "protomers" are the building blocks of the procapsid but their subunits are redistributed into different subcomplexes upon being incorporated into a nascent procapsid and are redistributed again in maturation. Assembly is a highly virus-specific process, making it a potential target for antiviral intervention.