Structure of Flexible Filamentous Plant Viruses

Department of Biological Sciences, Vanderbilt University, Box 351634, Station B, Nashville, TN 37235, USA.
Journal of Virology (Impact Factor: 4.44). 08/2008; 82(19):9546-54. DOI: 10.1128/JVI.00895-08
Source: PubMed


Flexible filamentous viruses make up a large fraction of the known plant viruses, but in comparison with those of other viruses, very little is known about their structures. We have used fiber diffraction, cryo-electron microscopy, and scanning transmission electron microscopy to determine the symmetry of a potyvirus, soybean mosaic virus; to confirm the symmetry of a potexvirus, potato virus X; and to determine the low-resolution structures of both viruses. We conclude that these viruses and, by implication, most or all flexible filamentous plant viruses share a common coat protein fold and helical symmetry, with slightly less than 9 subunits per helical turn.

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    • "Even for tobamoviruses, the X-ray fiber diffraction [2] and cryoelectron microscopy [3] data with a resolution of 3–5 Å are insufficient for elucidating the mechanisms of virus assembly in vitro and in vivo, especially since important differences between the results obtained by these two methods exist. For potyviruses, the best achievement in this field to date is 14 Å resolution fiber diffraction and cryoelectron microscopy data from Dr. Stubbs’s laboratory [4]. These data made it possible to estimate only overall dimensions of coat protein (CP) subunits in virions. "
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    PLoS ONE 07/2013; 8(7):e67830. DOI:10.1371/journal.pone.0067830 · 3.23 Impact Factor
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    • "Finch (1965) pointed out that these spacings and the distribution of intensities on the off-meridional layer lines suggest that there are 5q+1 coat protein subunits in five turns of the viral helix, where q is an integer. Although the possibility of 5q−1 could not be completely excluded, the pair of layer lines 20 and 21 near the meridian (Fig. 2) supports 5q+1; the pair would be 19 and 20 if the number of subunits in the repeating unit were 5q−1 (Kendall et al., 2008). "
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    • "). PVX has filamentous particles consisting of c. 1260 coat protein subunits encapsidating a single RNA molecule. Although an atomic resolution structure of the coat protein subunits is not available, the overall architecture of the viral particles is known (Kendall et al., 2008 "
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