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bioRxiv · 10.1101/2021.08.03.454973

Crystal structure of the potato leafroll virus coat protein and implications for viral assembly

Adams, M. C.·Schiltz, C. J.·Heck, M. L.·Chappie, J. S.
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Abstract

Luteoviruses, poleroviruses, and enamoviruses are insect-transmitted, agricultural pathogens that infect a wide array of staple food crops. Previous cryo-electron microscopy studies of virus-like particles indicate that luteovirid viral capsids are built from a structural coat protein that organizes with T=3 icosahedral symmetry. Here we present the crystal structure of a truncated version of the coat protein monomer from potato leafroll virus at 1.57-[A] resolution. In the crystal lattice, monomers pack into flat sheets that preserve the two-fold and three-fold axes of icosahedral symmetry and show minimal structural deviations when compared to the full-length subunits of the assembled virus-like particle. These observations have important implications in viral assembly and maturation, suggesting that the CP N-terminus and its interactions with RNA serve as a key driver for generating capsid curvature.

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Adams, M. C., Schiltz, C. J., Heck, M. L., Chappie, J. S.. 2021-08-03. Crystal structure of the potato leafroll virus coat protein and implications for viral assembly. https://doi.org/10.1101/2021.08.03.454973

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