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Simple and Robust in vivo and in vitro Approach for Studying Virus Assembly
Published on: March 1, 2012
Interactions between brome mosaic virus RNAs and cytoplasmic processing bodies
Carla J Beckham1, Heather R Light, T Amar Nissan
1Department of Molecular and Cellular Biology and Howard Hughes Medical Institute, The University of Arizona, Tucson, AZ 85721-0206, USA.
Journal of Virology
|July 5, 2007
Summary
Cytoplasmic processing bodies (P bodies) are crucial for plant virus RNA replication. Brome mosaic virus (BMV) RNAs accumulate in P bodies, suggesting a key role in viral RNA replication complex assembly.
Area of Science:
- Molecular Biology
- Virology
- Cell Biology
Background:
- Cytoplasmic processing bodies (P bodies) are dynamic cellular sites involved in mRNA metabolism, including storage, degradation, and translational control.
- Components of P bodies, such as the Lsm1-7p complex, Dhh1p, and Pat1p, are known to be essential for mRNA regulation and viral RNA replication.
- Brome mosaic virus (BMV) is a positive-strand RNA virus whose replication has been studied in yeast models.
Purpose of the Study:
- To investigate the subcellular localization of BMV genomic RNAs within yeast cells.
- To elucidate the role of P bodies in the replication cycle of BMV.
- To understand the interaction between viral components and P body factors during replication.
Main Methods:
- Subcellular localization studies of BMV RNAs in yeast using microscopy.
- Analysis of RNA localization dependence on cis-acting replication signals.
- Co-immunoprecipitation assays to detect interactions between viral proteins and P body components.
- Confocal microscopy to assess colocalization of viral RNA-dependent RNA polymerase and Lsm1p.
Main Results:
- BMV genomic RNAs (RNA2 and RNA3) were found to accumulate in P bodies.
- This accumulation was dependent on cis-acting RNA replication signals present in the viral RNAs.
- These signals also directed nonviral RNAs to P bodies.
- The viral RNA-dependent RNA polymerase was shown to co-immunoprecipitate with Lsm1p, a P body component.
- Partial colocalization was observed between the viral RNA-dependent RNA polymerase and Lsm1p.
Conclusions:
- BMV RNA accumulation in P bodies appears to be a critical step for viral RNA replication.
- P bodies may serve as platforms for the assembly of the viral RNA replication complex.
- These findings suggest a conserved mechanism for P body involvement in the replication of positive-strand RNA viruses.
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