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06:40
Temporal Analysis of the Nuclear-to-cytoplasmic Translocation of a Herpes Simplex Virus 1 Protein by Immunofluorescent Confocal Microscopy
Published on: November 4, 2018
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Membrane deformation and scission by the HSV-1 nuclear egress complex
Janna M Bigalke1, Thomas Heuser2, Daniela Nicastro3
1Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111, USA.
Nature Communications
|June 12, 2014
Summary
The herpesvirus nuclear egress complex (NEC) alone drives membrane budding for viral capsid release from the nucleus. This virus-encoded machinery self-assembles to mediate nuclear envelope vesiculation without cellular help.
Area of Science:
- Virology
- Cell Biology
- Structural Biology
Background:
- The nuclear egress complex (NEC) facilitates herpesvirus capsid exit from the nucleus.
- The exact mechanism of NEC-mediated nuclear envelope budding and potential cellular protein involvement remain unclear.
Purpose of the Study:
- To elucidate the HSV-1 NEC's role in nuclear egress.
- To determine if the NEC alone can mediate membrane budding and scission.
Main Methods:
- In vitro membrane budding assays using purified HSV-1 NEC.
- Analysis of NEC coat formation on budded vesicles.
- Comparison of in vitro budding topology with in vivo observations.
Main Results:
- HSV-1 NEC alone is sufficient for membrane budding and scission in vitro.
- The NEC forms ordered coats on vesicles, suggesting a scaffolding and constriction mechanism.
- In vitro budding topology mirrors in vivo nuclear egress and envelope vesiculation.
Conclusions:
- The NEC acts as a minimal, virus-encoded membrane-budding machine.
- Nuclear egress and envelope vesiculation do not require additional cellular factors beyond the NEC.
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