| analysis of nucleotide sequences and multimeric forms of a novel satellite rna associated with beet black scorch virus. | the full-length sequence of a satellite rna (sat-rna) of beet black scorch virus isolate x (bbsv-x) was determined. this agent is 615 nucleotides long and lacks extensive sequence homology with its helper virus or with other reported viruses. purified virus particles contained abundant single-stranded plus-sense monomers and smaller amounts of dimers. single-stranded rnas from total plant rna extracts also included primarily monomers and smaller amounts of dimers that could be revealed by hybrid ... | 2005 | 15731260 |
| oral administration of plant-based rotavirus vp6 induces antigen-specific igas, iggs and passive protection in mice. | plant viruses show significant potential as expression vectors for producing foreign proteins in plants. in this study, codon-optimized vp6 gene (svp6) of human rotavirus was engineered as a replacement to the coat protein (cp) open reading frame of beet black scorch virus (bbsv). in vitro-generated rna transcripts corresponding to the engineered virus were infectious when inoculated onto the leaves of chenopodium amaranticolor. molecular analysis revealed that svp6 was efficiently expressed and ... | 2010 | 20637305 |
| morphogenesis of endoplasmic reticulum membrane-invaginated vesicles during beet black scorch virus infection: role of auxiliary replication protein and new implications of three-dimensional architecture. | all well-characterized positive-strand rna viruses[(+)rna viruses] induce the formation of host membrane-bound viral replication complexes (vrcs), yet the underlying mechanism and machinery for vrc formation remain elusive. we report here the biogenesis and topology of the beet black scorch virus (bbsv) replication complex. distinct cytopathological changes typical of endoplasmic reticulum (er) aggregation and vesiculation were observed in bbsv-infected nicotiana benthamiana cells. immunogold la ... | 2015 | 25833056 |
| the r-rich motif of beet black scorch virus p7a movement protein is important for the nuclear localization, nucleolar targeting and viral infectivity. | beet black scorch virus (bbsv) encodes three movement proteins (p7a, p7b and p5') that facilitate its cell-to-cell movement. an arginine-rich motif of p7a n-terminus was found to determine nuclear and nucleolar localization. amino acids substitution or deletion of the r-rich motif interfered with p7a nuclear and nucleolar localization. bimolecular fluorescence complementation (bifc) assays revealed that p7a protein interacted with nicotiana benthamiana nuclear import factor importin α, suggestin ... | 2012 | 22626884 |
| two distinct sites are essential for virulent infection and support of variant satellite rna replication in spontaneous beet black scorch virus variants. | spontaneous point mutations of virus genomes are important in rna virus evolution and often result in modifications of their biological properties. spontaneous variants of beet black scorch virus (bbsv) and its satellite (sat) rna were generated from cdna clones by serial propagation in chenopodium amaranticolor and nicotiana benthamiana. inoculation with recombinant rnas synthesized in vitro revealed bbsv variants with divergent infectious phenotypes that affected either symptom expression or r ... | 2012 | 22971822 |
| highly specific detection of five exotic quarantine plant viruses using rt-pcr. | to detect five plant viruses (beet black scorch virus, beet necrotic yellow vein virus, eggplant mottled dwarf virus, pelargonium zonate spot virus, and rice yellow mottle virus) for quarantine purposes, we designed 15 rt-pcr primer sets. primer design was based on the nucleotide sequence of the coat protein gene, which is highly conserved within species. all but one primer set successfully amplified the targets, and gradient pcrs indicated that the optimal temperature for the 14 useful primer s ... | 2013 | 25288934 |
| n-terminal basic amino acid residues of beet black scorch virus capsid protein play a critical role in virion assembly and systemic movement. | beet black scorch virus (bbsv) is a small single-stranded, positive-sense rna plant virus belonging to the genus necrovirus, family tombusviridae. its capsid protein (cp) contains a 13 amino acid long basic region at the n-terminus, rich in arginine and lysine residues, which is thought to interact with viral rna to initiate virion assembly. | 2013 | 23786675 |
| phosphorylation of beet black scorch virus coat protein by pka is required for assembly and stability of virus particles. | plant virus coat proteins (cps) play a fundamental role in protection of genomic rnas, virion assembly, and viral movement. although phosphorylation of several cps during virus infection have been reported, little information is available about cp phosphorylation of the spherical rna plant viruses. here, we demonstrate that the cp of beet black scorch virus (bbsv), a member of the genus necrovirus, can be phosphorylated at threonine-41 (t41) by camp-dependent protein kinase (pka)-like kinase in ... | 2015 | 26108567 |
| improved pathogenicity of a beet black scorch virus variant by low temperature and co-infection with its satellite rna. | co-infection of none-coding satellite rnas (sat-rnas) usually inhibits replication and attenuates disease symptoms of helper viruses. however, we find that the sat-rna of beet black scorch virus (bbsv) and low temperature (18°c) additively enhance the systemic infection of bbsv in nicotiana benthamiana. northern blotting hybridization revealed a relatively reduced accumulation of bbsv-derived small interfering rnas (sirnas) in presence of sat-rna as compared to that of bbsv alone. cloning and se ... | 2016 | 27867378 |
| validation of reference genes for gene expression studies in virus-infected nicotiana benthamiana using quantitative real-time pcr. | nicotiana benthamiana is the most widely-used experimental host in plant virology. the recent release of the draft genome sequence for n. benthamiana consolidates its role as a model for plant-pathogen interactions. quantitative real-time pcr (qpcr) is commonly employed for quantitative gene expression analysis. for valid qpcr analysis, accurate normalisation of gene expression against an appropriate internal control is required. yet there has been little systematic investigation of reference ge ... | 2012 | 23029521 |
| nuclear localization of beet black scorch virus capsid protein and its interaction with importin α. | beet black scorch virus (bbsv) is a positive-sense, single-stranded rna virus belonging to necrovirus genus. in order to better understand the life cycle of bbsv, we have investigated the subcellular localization of bbsv capsid protein (cp) by its fusion with green fluorescent protein (gfp) agroinfiltrated into nicotiana benthamiana leaves and by particle bombardment into onion (allium cepa) epidermal cells. confocal laser scanning microscopy (clsm) showed that bbsv cp fused to gfp displayed enh ... | 2010 | 21056066 |
| characterization of a u.s. isolate of beet black scorch virus. | abstract the first reported u.s. isolate of beet black scorch necrovirus (bbsv) was obtained and characterized. host range of the virus for localized and occasionally systemic infection included the chenopodiaceae and tetragonia expansa; nicotiana benthamiana supported symptomless systemic infection by the virus. the complete nucleotide sequence of the genomic rna of the virus, designated bbsv-co, exhibits 93% similarity to the genome of the 'ningxia' isolate of bbsv from china. amino acid seque ... | 2007 | 18943682 |
| molecular and serological characterization of an iranian isolate of beet black scorch virus. | an isolate of beet black scorch virus (bbsv) was obtained from iranian sugar beet roots. its genome organization closely resembles that of the previously described chinese and north american isolates, but the nucleotide sequences of the three isolates differ considerably. most of the nucleotide exchanges, however, are silent, and the iranian and the chinese isolates were serologically indistinguishable. beets infected by the iranian bbsv did not show black scorch symptoms, but severe root bearde ... | 2008 | 18548319 |
| analysis of the subgenomic rnas and the small open reading frames of beet black scorch virus. | a full-length cdna of the genome of beet black scorch virus (bbsv), isolate ningxia, was constructed and modified by site-directed mutagenesis to permit in vitro transcription of mutant viral rnas. two subgenomic (sg) rnas (sgrna1 and sgrna2) appeared during bbsv replication. mutagenesis revealed that sgrna1 transcription was initiated at g2209 within the p82 polymerase subunit open reading frame (orf) and that transcription of sgrna2 began at g2526 within the nested p7b/p5' orf. initiation-codo ... | 2006 | 16963767 |
| the complete nucleotide sequence of beet black scorch virus (bbsv), a new member of the genus necrovirus. | the complete nucleotide sequence of beet black scorch virus (bbsv) was determined. the bbsv genome is composed of 3641 nucleotides and has similar organization with tobacco necrosis virus d of 61% nucleotide identity. the 5'-proximal open reading frame (orf) encodes a putative 23 kda protein and a 82 kda protein by reading-through of an amber termination codon. three small orfs located in the center of the genome may encode for a 4.2 kda protein and two 7 kda proteins. the 3'-proximal orf encode ... | 2002 | 12491108 |