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Detection of Viral RNA by Fluorescence in situ Hybridization (FISH)
Published on: May 5, 2012
Viral IRES RNA structures and ribosome interactions.
1Department of Biochemistry and Molecular Genetics, University of Colorado Denver School of Medicine, Mail stop 8101, PO Box 6511, Aurora, CO 80045, USA. Jeffrey.kieff@uchsc.edu
Trends in Biochemical Sciences
|May 13, 2008
Summary
Viral internal ribosome-entry sites (IRESs) bypass the standard cap-dependent mRNA translation initiation in eukaryotes. Recent structural studies reveal diverse 3D RNA structures used by IRESs to hijack the ribosome, with some common interaction features.
Area of Science:
- Molecular Biology
- Virology
- Structural Biology
Background:
- Eukaryotic protein synthesis typically requires mRNA 'cap' structures and associated proteins for ribosome recruitment.
- Pathogenic viruses often employ cap-independent translation mechanisms, utilizing RNA structures instead of the cap.
- Internal ribosome-entry sites (IRESs) are RNA elements that facilitate cap-independent translation initiation.
Purpose of the Study:
- To elucidate the structural basis of how viral IRES RNAs bind and recruit ribosomes.
- To understand the diversity and commonalities in the three-dimensional structures of IRES RNAs.
- To reveal the mechanisms by which viral IRESs hijack the host cell's protein synthesis machinery.
Main Methods:
- Determining high-resolution structures of IRES RNAs.
- Analyzing structures of IRES-ribosome complexes.
- Comparative structural analysis of different viral IRES elements.
Main Results:
- Viral IRES RNAs utilize specific three-dimensional structures to mediate cap-independent translation.
- Recent structural data reveals diverse structural strategies employed by different IRESs.
- Common structural features exist in how various IRESs interact with the ribosome.
Conclusions:
- Viral IRESs exhibit significant structural diversity in their interaction with the ribosome.
- Understanding these structures provides insights into viral replication strategies.
- Structural insights pave the way for potential antiviral therapeutic targets.
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