Novel Inter-Subunit Contacts in Barley Stripe Mosaic Virus Revealed by Cryo-Electron Microscopy.
Barley stripe mosaic virus (BSMV, genus Hordeivirus) is a rod-shaped single-stranded RNA virus similar to viruses of the structurally characterized and well-studied genus Tobamovirus. Here we report the first high-resolution structure of BSMV at 4.1 Å obtained by cryo-electron microscopy. We discovered that BSMV forms two types of virion that differ in the number of coat protein (CP) subunits per turn and interactions between the CP subunits. While BSMV and tobacco mosaic virus CP subunits have a similar fold and interact with RNA using conserved residues, the axial contacts between the CP of these two viral groups are considerably different. BSMV CP subunits lack substantial axial contacts and are held together by a previously unobserved lateral contact formed at the virion surface via an interacting loop, which protrudes from the CP hydrophobic core to the adjacent CP subunit. These data provide an insight into diversity in structural organization of helical viruses.
Institute of Structural and Molecular Biology, UCL and Birkbeck, Malet Street, London WC1E 7HX, UK.
Daniel Kofi
DK
Clare
A.V. Shubnikov Institute of Crystallography RAS, 59 Leninsky Avenue, 119333 Moscow, Russia.
Eugenia V
EV
Pechnikova
Department of Biology, Moscow State University, 1 Leninskie Gory, Building 12, 119991 Moscow, Russia.
Eugene V
EV
Skurat
A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, 119992 Moscow, Russia.
Valentin V
VV
Makarov
A.V. Shubnikov Institute of Crystallography RAS, 59 Leninsky Avenue, 119333 Moscow, Russia; Department of Biology, Moscow State University, 1 Leninskie Gory, Building 12, 119991 Moscow, Russia.
Olga S
OS
Sokolova
A.N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, 119992 Moscow, Russia.
Andrey G
AG
Solovyev
Institute of Structural and Molecular Biology, UCL and Birkbeck, Malet Street, London WC1E 7HX, UK. Electronic address: e.orlova@mail.cryst.bbk.ac.uk.
Elena V
EV
Orlova
D001665:Binding Sites; D036022:Capsid Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D020285:Cryoelectron Microscopy; D018360:Crystallography, X-Ray; D015967:Gene Expression Regulation, Viral; D001467:Hordeum / Q000821:virology; D057927:Hydrophobic and Hydrophilic Interactions; D008958:Models, Molecular; D010935:Plant Diseases / Q000821:virology; D018515:Plant Leaves / Q000821:virology; D010942:Plant Viruses / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D017510:Protein Folding; D054730:Protein Interaction Domains and Motifs; D017433:Protein Structure, Secondary; D021122:Protein Subunits / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D012328:RNA Viruses / Q000235:genetics / Q000378:metabolism*; D012367:RNA, Viral / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D014026:Nicotiana / Q000821:virology; D014027:Tobacco Mosaic Virus / Q000235:genetics / Q000378:metabolism; D014771:Virion / Q000235:genetics / Q000378:metabolism*
D036022:Capsid Proteins; D021122:Protein Subunits; D012367:RNA, Viral; D011993:Recombinant Fusion Proteins
BSMV; CCD camera; Cryo-EM; helical virus; single particle processing