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Bacterial Artificial Chromosomes: A Functional Genomics Tool for the Study of Positive-strand RNA Viruses
Published on: December 29, 2015
Cucumber mosaic virus, a model for RNA virus evolution
1Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, OK 73402, USA.
Molecular Plant Pathology
|June 25, 2010
Summary
Cucumber mosaic virus (CMV) is a broad-host-range virus with a segmented RNA genome. Its satellite RNAs (satRNAs) can significantly alter disease symptoms in plants.
Area of Science:
- Plant virology
- Molecular biology
- Biochemistry
Background:
- Cucumber mosaic virus (CMV) is the type member of the Cucumovirus genus, family Bromoviridae.
- CMV has a broad host range, infecting over 1000 plant species across 85 families.
- CMV particles are icosahedral (T=3), approximately 29 nm in diameter, containing 18% RNA.
Purpose of the Study:
- To describe the taxonomic relationships, physical properties, and biological characteristics of Cucumber mosaic virus (CMV).
- To highlight the role of satellite RNAs (satRNAs) in modulating CMV-induced symptoms.
- To provide an overview of CMV's extensive host range and transmission mechanisms.
Main Methods:
- Genomic analysis of CMV RNA components (RNA 1, 2, 3, and subgenomic RNAs).
- Structural characterization of CMV virions (size, symmetry, composition).
- Investigation of CMV host range and aphid-mediated nonpersistent transmission.
Main Results:
- CMV has three genomic RNAs (RNA 1, 2, 3) and a subgenomic RNA (RNA 4), with RNA 3 exchangeable within the genus.
- CMV virions are labile, icosahedral particles (29 nm) composed of 180 subunits and 18% RNA.
- CMV exhibits an exceptionally broad host range and is transmitted by aphids; satellite RNAs can alter disease phenotypes.
Conclusions:
- CMV is a significant plant pathogen due to its wide host range and the influence of satRNAs on disease severity.
- Understanding CMV's genomic structure and physical properties is crucial for disease management.
- CMV's biological characteristics, including its broad host range and aphid transmission, contribute to its widespread impact on agriculture.
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