The crystallographic structure of Panicum Mosaic Virus (PMV).Makino, D.L., Larson, S.B., McPherson, A.
(2013) J.Struct.Biol. 181: 37-52
- PubMed: 23123270
- DOI: 10.1016/j.jsb.2012.10.012
- Primary Citation of Related Structures:
- PubMed Abstract:
- Preliminary analysis of crystals of panicum mosaic virus (PMV) by X-ray diffraction and atomic force microscopy.
Makino, D.L.,Larson, S.B.,McPherson, A.
(2005) Acta Crystallogr.,Sect.D 61: 173
The structure of Panicum Mosaic Virus (PMV) was determined by X-ray diffraction analysis to 2.9Å resolution. The crystals were of pseudo symmetry F23; the true crystallographic unit cell was of space group P2(1) with a=411.7Å, b=403.9Å and c=412.5Å, ...
The structure of Panicum Mosaic Virus (PMV) was determined by X-ray diffraction analysis to 2.9Å resolution. The crystals were of pseudo symmetry F23; the true crystallographic unit cell was of space group P2(1) with a=411.7Å, b=403.9Å and c=412.5Å, with β=89.7°. The asymmetric unit was two entire T=3 virus particles, or 360 protein subunits. The structure was solved by conventional molecular replacement from two distant homologues, Cocksfoot Mottle Virus (CfMV) and Tobacco Necrosis Virus (TNV), of ∼20% sequence identity followed by phase extension. The model was initially refined with exact icosahedral constraints and then with icosahedral restraints. The virus has Ca(++) ions octahedrally coordinated by six aspartic acid residues on quasi threefold axes, which is completely different than for either CfMV or TNV. Amino terminal residues 1-53, 1-49 and 1-21 of the A, B and C subunits, respectively, and the four C-terminal residues (239-242) are not visible in electron density maps. The additional ordered residues of the C chain form a prominent "arm" that intertwines with symmetry equivalent "arms" at icosahedral threefold axes, as was seen in both CfMV and TNV. A 17 nucleotide hairpin segment of genomic RNA is icosahedrally ordered and bound at 60 equivalent sites at quasi twofold A-B subunit interfaces at the interior surface of the capsid. This segment of RNA may serve as a conformational switch for coat protein subunits, as has been proposed for similar RNA segments in other viruses.
Department of Molecular Biology and Biochemistry, The University of California, Irvine, CA 92697-3900, USA.