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Single-particle studies of the effects of RNA-protein interactions on the self-assembly of RNA virus particles.

ABSTRACT: Understanding the pathways by which simple RNA viruses self-assemble from their coat proteins and RNA is of practical and fundamental interest. Although RNA-protein interactions are thought to play a critical role in the assembly, our understanding of their effects is limited because the assembly process is difficult to observe directly. We address this problem by using interferometric scattering microscopy, a sensitive optical technique with high dynamic range, to follow the in vitro assembly kinetics of more than 500 individual particles of brome mosaic virus (BMV)-for which RNA-protein interactions can be controlled by varying the ionic strength of the buffer. We find that when RNA-protein interactions are weak, BMV assembles by a nucleation-and-growth pathway in which a small cluster of RNA-bound proteins must exceed a critical size before additional proteins can bind. As the strength of RNA-protein interactions increases, the nucleation time becomes shorter and more narrowly distributed, but the time to grow a capsid after nucleation is largely unaffected. These results suggest that the nucleation rate is controlled by RNA-protein interactions, while the growth process is driven less by RNA-protein interactions and more by protein-protein interactions and intraprotein forces. The nucleated pathway observed with the plant virus BMV is strikingly similar to that previously observed with bacteriophage MS2, a phylogenetically distinct virus with a different host kingdom. These results raise the possibility that nucleated assembly pathways might be common to other RNA viruses.

SUBMITTER: Garmann RF

PROVIDER: S-EPMC9522328 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

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Single-particle studies of the effects of RNA-protein interactions on the self-assembly of RNA virus particles.

Garmann Rees F RF Goldfain Aaron M AM Tanimoto Cheylene R CR Beren Christian E CE Vasquez Fernando F FF Villarreal Daniel A DA Knobler Charles M CM Gelbart William M WM Manoharan Vinothan N VN

Proceedings of the National Academy of Sciences of the United States of America 20220919 39

Understanding the pathways by which simple RNA viruses self-assemble from their coat proteins and RNA is of practical and fundamental interest. Although RNA-protein interactions are thought to play a critical role in the assembly, our understanding of their effects is limited because the assembly process is difficult to observe directly. We address this problem by using interferometric scattering microscopy, a sensitive optical technique with high dynamic range, to follow the in vitro assembly k ...[more]

PMID: 36122222

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Dataset Information

Single-particle studies of the effects of RNA-protein interactions on the self-assembly of RNA virus particles.

Publications

Single-particle studies of the effects of RNA-protein interactions on the self-assembly of RNA virus particles.

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