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09:27
Methodology for the Efficient Generation of Fluorescently Tagged Vaccinia Virus Proteins
Published on: January 17, 2014
Membrane rupture generates single open membrane sheets during vaccinia virus assembly.
Petr Chlanda1, Maria Alejandra Carbajal, Marek Cyrklaff
1Department of Molecular Structural Biology, Max Planck Institute for Biochemistry, Am Klopferspitz 18, Martinsried 82152, Germany. chlanda@embl.de
Cell Host & Microbe
|July 21, 2009
Summary
Poxviruses acquire envelopes from cellular membranes, challenging the idea of de novo synthesis. Cryo-electron tomography reveals these viral membranes originate from existing cellular membranes that form open compartments.
Area of Science:
- Cellular biology
- Virology
- Membrane biogenesis
Background:
- Cellular membrane dynamics rely on fusion and fission for compartment maintenance.
- Viral envelope acquisition typically follows these cellular principles.
- Previous electron microscopy (EM) suggested poxviruses form membranes de novo.
Purpose of the Study:
- To investigate the origin and structure of poxvirus membranes.
- To clarify the mechanism of poxvirus envelope formation.
- To analyze viral membrane biogenesis in a near-native state using advanced imaging.
Main Methods:
- Cryopreservation techniques to maintain cellular structures.
- 3D imaging using electron tomography (ET).
- Cryo-electron microscopy (cryo-EM) for high-resolution visualization.
Main Results:
- Poxvirus precursor membranes appear as open sheets stabilized by protein scaffolds.
- Electron tomography demonstrates these membranes originate from pre-existing cellular membranes.
- The process involves the rupture of cellular membranes to form open compartments, not de novo synthesis.
Conclusions:
- Poxvirus envelope formation involves cellular membranes rupturing to create open compartments.
- This mechanism differs from established de novo membrane biogenesis pathways.
- Poxvirus infection provides a unique model for studying open membrane sheet formation in the cytoplasm.
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