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Asymmetric cryo-EM reconstruction of phage MS2 reveals genome structure in situ.

ABSTRACT: In single-stranded ribonucleic acid (RNA) viruses, virus capsid assembly and genome packaging are intertwined processes. Using cryo-electron microscopy and single particle analysis we determined the asymmetric virion structure of bacteriophage MS2, which includes 178 copies of the coat protein, a single copy of the A-protein and the RNA genome. This reveals that in situ, the viral RNA genome can adopt a defined conformation. The RNA forms a branched network of stem-loops that almost all allocate near the capsid inner surface, while predominantly binding to coat protein dimers that are located in one-half of the capsid. This suggests that genomic RNA is highly involved in genome packaging and virion assembly.

SUBMITTER: Koning RI

PROVIDER: S-EPMC5007439 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Asymmetric cryo-EM reconstruction of phage MS2 reveals genome structure in situ.

Koning Roman I RI Gomez-Blanco Josue J Akopjana Inara I Vargas Javier J Kazaks Andris A Tars Kaspars K Carazo José María JM Koster Abraham J AJ

Nature communications 20160826

In single-stranded ribonucleic acid (RNA) viruses, virus capsid assembly and genome packaging are intertwined processes. Using cryo-electron microscopy and single particle analysis we determined the asymmetric virion structure of bacteriophage MS2, which includes 178 copies of the coat protein, a single copy of the A-protein and the RNA genome. This reveals that in situ, the viral RNA genome can adopt a defined conformation. The RNA forms a branched network of stem-loops that almost all allocate ...[more]

PMID: 27561669

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