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Bacterial Artificial Chromosomes: A Functional Genomics Tool for the Study of Positive-strand RNA Viruses
Published on: December 29, 2015
The polymerase of negative-stranded RNA viruses
Benjamin Morin1, Philip J Kranzusch, Amal A Rahmeh
1Department of Microbiology & Immunobiology, Harvard Medical School, Boston, MA, United States.
Current Opinion in Virology
|April 23, 2013
Summary
Negative-sense RNA viruses use distinct RNA polymerases for transcription. Viral RNA must transiently detach from nucleocapsid proteins for synthesis, revealing evolutionary insights into RNA replication machines.
Area of Science:
- Virology
- Structural Biology
- Molecular Evolution
Background:
- Negative-sense RNA viruses package RNA-protein complexes for transcription.
- RNA is protected by nucleocapsid proteins (NP) during viral replication.
Purpose of the Study:
- Compare RNA polymerases of nonsegmented (NNS) and segmented (SNS) negative-sense RNA viruses.
- Analyze structural data to understand viral RNA synthesis mechanisms.
Main Methods:
- Literature review and comparative analysis of existing structural data.
- Focus on atomic-level understanding of NP-RNA interactions.
Main Results:
- RNA dissociation from NP is essential for RNA synthesis in both NNS and SNS viruses.
- Viral polymerases exhibit distinct strategies for transcription and mRNA cap formation.
Conclusions:
- Comparative analysis reveals evolutionary relationships between viral RNA synthesis machinery.
- Two distinct mRNA cap formation mechanisms are employed by these viruses.
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