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Measurements of the self-assembly kinetics of individual viral capsids around their RNA genome.

ABSTRACT: Self-assembly is widely used by biological systems to build functional nanostructures, such as the protein capsids of RNA viruses. But because assembly is a collective phenomenon involving many weakly interacting subunits and a broad range of timescales, measurements of the assembly pathways have been elusive. We use interferometric scattering microscopy to measure the assembly kinetics of individual MS2 bacteriophage capsids around MS2 RNA. By recording how many coat proteins bind to each of many individual RNA strands, we find that assembly proceeds by nucleation followed by monotonic growth. Our measurements reveal the assembly pathways in quantitative detail and also show their failure modes. We use these results to critically examine models of the assembly process.

SUBMITTER: Garmann RF

PROVIDER: S-EPMC6842639 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Measurements of the self-assembly kinetics of individual viral capsids around their RNA genome.

Garmann Rees F RF Goldfain Aaron M AM Manoharan Vinothan N VN

Proceedings of the National Academy of Sciences of the United States of America 20190930 45

Self-assembly is widely used by biological systems to build functional nanostructures, such as the protein capsids of RNA viruses. But because assembly is a collective phenomenon involving many weakly interacting subunits and a broad range of timescales, measurements of the assembly pathways have been elusive. We use interferometric scattering microscopy to measure the assembly kinetics of individual MS2 bacteriophage capsids around MS2 RNA. By recording how many coat proteins bind to each of ma ...[more]

PMID: 31570619

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