Closteroviruses possess exceptionally long filamentous virus particles that mediate protection and active transport of the genomic RNA within infected plants. These virions are composed of a long "body" and short "tail" whose principal components are the major and minor capsid proteins, respectively. Here we use biochemical, genetic, and ultrastructural analyses to dissect the molecular composi...

The complete nucleotide sequence of a novel member of the genus Crinivirus (family Closteroviridae), isolated from blackberry and tentatively named Blackberry yellow vein associated virus, was determined. The virus possesses a bipartite genome. RNA 1 is 7,801 nucleotides in length and papain-like protease, methyltransferase, RNA helicase and RNA-dependent RNA polymerase motifs have been identif...

The large RNA genome of Citrus tristeza virus (CTV; ca. 20 kb) contains 12 open reading frames, with the 3'-terminal one corresponding to a protein of 209 amino acids (p23) that is expressed from an abundant subgenomic RNA. p23, an RNA-binding protein with a putative zinc-finger domain and some basic motifs, is unique to CTV because no homologs have been found in other closteroviruses, includin...

uring the 1980s, crisphead lettuce, butterhead lettuce, and spinach crops in western Oregon (Fig. 1) became increasingly damaged by beet western yellows luteovirus (BWYV) (5,8) infection (15), a previously insignificant problem in this area. Utilizing double antibody sandwich enzyme-linked immunosorbent assay (DASELISA) methodology (2), we identified potential BWYV inoculum sources in vicinitie...

Monique Beuve, Institut National de la Recherche Agronomique (INRA), UMR Santé de la Vigne et Qualité du Vin (SVQV), Laboratoire Virologie & Vection, 68021 Colmar cedex, France, and Université L. Pasteur, 67000 Strasbourg, France; Mark Stevens, Broom’s Barn Research Center, Higham, Bury St. Edmunds, Suffolk, IP28 6 NP, UK; Hsing-Yeh Liu and William M. Wintermantel, United States Department of A...

The Sugarcane yellow leaf virus (SCYLV) P0, a member of the highly heterologous proteins of poleroviruses, is a suppressor of posttranscriptional gene silencing (PTGS) and has additional activities not seen in other P0 proteins. The P0 protein in previously tested poleroviruses (Beet western yellows virus and Cucurbit aphid-borne yellows virus), suppresses local, but not systemic, PTGS induced ...