Structure of the mite-transmitted Blackcurrant reversion nepovirus using electron cryo-microscopy.
Blackcurrant reversion nepovirus (BRV; genus Nepovirus) has a single-stranded, bipartite RNA genome surrounded by 60 copies of a single capsid protein (CP). BRV is the most important mite-transmitted viral pathogen of the Ribes species. It is the causal agent of blackcurrant reversion disease. We determined the structure of BRV to 1.7 nm resolution using electron cryo- microscopy (cryoEM) and image reconstruction. The reconstruction reveals a pseudo T=3 viral capsid similar to that of tobacco ringspot virus (TRSV). We modelled the BRV capsid protein to that of TRSV and fitted it into the cryoEM reconstruction. The fit indicated that the extended C-terminus of BRV-CP is located on the capsid surface and the N-terminus on the interior. We generated peptide antibodies to two putatively exposed C-terminal sequences and these reacted with the virus. Hence homology modelling may be useful for defining epitopes for antibody generation for diagnostic testing of BRV in commercial crops.
Institute of Biotechnology, P.O. Box 65 (Viikinkaari 1), FIN-00014 University of Helsinki, Finland.
Jani J T
JJ
Seitsonen
Petri
P
Susi
Anne
A
Lemmetty
Sarah J
SJ
Butcher
D000595:Amino Acid Sequence; D000818:Animals; D036022:Capsid Proteins / Q000737:chemistry / Q000235:genetics / Q000648:ultrastructure*; D027465:Chenopodium quinoa / Q000821:virology; D020285:Cryoelectron Microscopy / Q000379:methods*; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008925:Mites / Q000821:virology*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017860:Nepovirus / Q000648:ultrastructure*; D012367:RNA, Viral / Q000737:chemistry / Q000235:genetics / Q000648:ultrastructure
D036022:Capsid Proteins; D012367:RNA, Viral; C113735:coat protein, blackcurrant reversion-associated nepovirus