Abstract
Comoviruses are small, icosahedral viruses with a diameter of approx 28 nm (Fig. 1). Presently the genus Comovirus is comprised of 15 different viruses, of which the type species, cowpea mosaic virus (CPMV), is the most thoroughly studied (1,2). All viruses are transmitted by beetles and have a rather narrow host range. Most comoviruses have legumes as their natural hosts and usually cause mosaic or mottling symptoms. Comoviruses are mechanically transmissible, and can replicate to high levels in infected cells. Purified preparations of comoviruses consist of two, sometimes three, distinguishable particles, which can be separated by centrifugation on sucrose density gradients. These particles are designated as bottom (B), middle (M), and top (T) component, corresponding to their position in the centrifuge tube. The B- and M-component are nucleoprotein particles, each containing a segment of the single-stranded, bipartite RNA genome (denoted RNA-1 and RNA-2, respectively); T-component consists of empty protein shells. Both B- and M-components, or their RNAs, are necessary for infectivity (3).
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References
Eggen, E. and Van Kammen, A. (1988) RNA replication in comoviruses, in RNA Genetics, vol. 1 (Ahlquist, A. Holland, J., and Domingo, E., eds.), CRC, Boca Raton, FL, pp. 49–69.
Goldbach, R. and Wellink, J. (1996) Comoviruses: molecular biology and replication, in The Plant Viruses, vol. 5 (Harrison, B. D. and Murant, A. F., eds.), Plenum, New York, pp. 35–76.
Van Kammen, A. (1968) The relationship between the components of cowpea mosaic virus. I. Two ribonucleoprotein particles necessary for the infectivity of CPMV. Virology 34, 312–318.
Hebert, T. T. (1963) Precipitation of plant viruses by polyethylene glycol. Phytopathology 53, 362–369.
Zimmern, D. (1975) The 5′ end group of tobacco mosaic virus RNA is m7 G5′ppp5′ Gp. Nucleic Acids Res. 2, 1189–1201.
Van Kammen, A. (1967) Purification and properties of the components of cowpea mosaic virus. Virology 31, 633–642.
Bruening, G. and Agrawal, H. O. (1967) Infectivity of a mixture of cowpea mosaic virus ribonucleoprotein components. Virology 32, 306–320.
Oxelfelt, P. (1976) Biological and physicochemical characteristics of three strains of red clover mottle virus. Virology 74, 73–80.
Goldbach, R. Rezelman, G., and Van Kammen, A. (1980) Independent replication and expression of B-component RNA of cowpea mosaic virus. Nature 286, 297–300.
Bruening, G. (1977) Plant comoviruses: two component systems, in Comprehensive Virology, vol. 11 (Fraenkel-Conrad, H. and Wagner, R. R., eds.), Plenum, New York, pp. 55–141.
Holness, C. L., Lomonossoff, G. P., Evans, D., and Maule, A. J. (1989) Identification of the initiation codons for translation of cowpea mosaic virus middle component RNA using site-directed mutagenesis of an infectious cDNA clone. Virology 172, 311–320.
Van Klootwijk, J., Klein, I., Zabel, P., and Van Kammen, A. (1977) Cowpea mosaic virus RNAs have neither m7GpppN⋯ nor mono-, di-or triphosphates ar their 5′ ends. Cell 11, 73–82.
Hiebert, E. and Purcifull, D. E. (1981) Mapping of the two coat protein genes on the middle RNA component of squash mosaic virus (comovirus group). Virology 113, 630–636.
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© 1998 Humana Press Inc.
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Wellink, J. (1998). Comovirus Isolation and RNA Extraction. In: Foster, G.D., Taylor, S.C. (eds) Plant Virology Protocols. Methods in Molecular Biology™, vol 81. Humana Press. https://doi.org/10.1385/0-89603-385-6:205
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DOI: https://doi.org/10.1385/0-89603-385-6:205
Publisher Name: Humana Press
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