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Remodeling nuclear architecture allows efficient transport of herpesvirus capsids by diffusion.

ABSTRACT: The nuclear chromatin structure confines the movement of large macromolecular complexes to interchromatin corrals. Herpesvirus capsids of approximately 125 nm assemble in the nucleoplasm and must reach the nuclear membranes for egress. Previous studies concluded that nuclear herpesvirus capsid motility is active, directed, and based on nuclear filamentous actin, suggesting that large nuclear complexes need metabolic energy to escape nuclear entrapment. However, this hypothesis has recently been challenged. Commonly used microscopy techniques do not allow the imaging of rapid nuclear particle motility with sufficient spatiotemporal resolution. Here, we use a rotating, oblique light sheet, which we dubbed a ring-sheet, to image and track viral capsids with high temporal and spatial resolution. We do not find any evidence for directed transport. Instead, infection with different herpesviruses induced an enlargement of interchromatin domains and allowed particles to diffuse unrestricted over longer distances, thereby facilitating nuclear egress for a larger fraction of capsids.

SUBMITTER: Bosse JB

PROVIDER: S-EPMC4620878 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Remodeling nuclear architecture allows efficient transport of herpesvirus capsids by diffusion.

Bosse Jens B JB Hogue Ian B IB Feric Marina M Thiberge Stephan Y SY Sodeik Beate B Brangwynne Clifford P CP Enquist Lynn W LW

Proceedings of the National Academy of Sciences of the United States of America 20151005 42

The nuclear chromatin structure confines the movement of large macromolecular complexes to interchromatin corrals. Herpesvirus capsids of approximately 125 nm assemble in the nucleoplasm and must reach the nuclear membranes for egress. Previous studies concluded that nuclear herpesvirus capsid motility is active, directed, and based on nuclear filamentous actin, suggesting that large nuclear complexes need metabolic energy to escape nuclear entrapment. However, this hypothesis has recently been ...[more]

PMID: 26438852

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Remodeling nuclear architecture allows efficient transport of herpesvirus capsids by diffusion.

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Remodeling nuclear architecture allows efficient transport of herpesvirus capsids by diffusion.

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