| epitope mapping on fragments of beet necrotic yellow vein virus coat protein. | the location of five sds-stable epitopes on the coat protein (cp) of beet necrotic yellow vein virus was determined by reacting escherichia coli-expressed free cp, as well as fusion proteins (fp) containing fragments of the cp, with polyclonal and monoclonal antibodies on western blots. epitope 1, which has previously been found to be exposed on only one extremity of the virus particle, was located in the region between amino acids (aa) 1 and 7, i.e. on the n terminus of the cp. it was blocked w ... | 1992 | 1372040 |
| computer-assisted assignment of functional domains in the nonstructural polyprotein of hepatitis e virus: delineation of an additional group of positive-strand rna plant and animal viruses. | computer-assisted comparison of the nonstructural polyprotein of hepatitis e virus (hev) with proteins of other positive-strand rna viruses allowed the identification of the following putative functional domains: (i) rna-dependent rna polymerase, (ii) rna helicase, (iii) methyltransferase, (iv) a domain of unknown function ("x" domain) flanking the papain-like protease domains in the polyproteins of animal positive-strand rna viruses, and (v) papain-like cysteine protease domain distantly relate ... | 1992 | 1518855 |
| cis-active sequences near the 5'-termini of beet necrotic yellow vein virus rnas 3 and 4. | rnas 3 and 4 of the multicomponent genome of beet necrotic yellow vein virus are dispensable for infection of chenopodium quinoa leaves. we have used mutagenesis of biologically active rna 3 transcripts to identify 5'-proximal sequences essential in cis for rna 3 amplification. one such element, box i, (nucleotides 283-292) was complementary to the first 10 residues (box i') following the 5'-terminal cap. a second cis-active element (box ii) was identified between nucleotides 237-244 and was com ... | 1992 | 1529554 |
| two proteins encoded by beet necrotic yellow vein virus rna 3 influence symptom phenotype on leaves. | rna 3 of the beet necrotic yellow vein virus (bnyvv) quadripartite rna genome is not essential for virus multiplication on leaves of tetragonia expansa but has dramatic effects on symptom expression. virus isolates containing rna 3 produce bright yellow local lesions while isolates lacking rna 3 produce much milder symptoms. using directed mutagenesis of cdna clones followed by in vitro synthesis of biologically active transcripts, a 25 kda open reading frame (orf) of rna 3 was shown to be respo ... | 1992 | 1537331 |
| single- and double-stranded rnas associated with an isolate of beet soil-borne virus. | ethidium bromide staining of electrophoretically separated ssrnas and dsrnas as well as northern blot analyses with cdna clones suggested that the genome of the ahlum serotype of beet soil-borne virus (bsbv) consists of two major ssrna species of approximately 3.6 and 3.2 kb, respectively, and possibly a minor ssrna of approximately 6.0 kb. a few of our clones hybridized with both the 3.6-kb and the 3.2-kb rnas, the majority of the clones, however, hybridized only with the 3.2-kb rna. the 3.2-kb ... | 1992 | 1568837 |
| a comparison, using dsrna analysis, between beet soil-borne virus and some other tubular viruses isolated from sugar beet. | double-stranded rna preparations from chenopodium quinoa leaves inoculated with two english isolates of beet soil-borne virus (bsbv), bsbv-n and bsbv-452n, a french isolate of beet necrotic yellow vein virus (bnyvv), a swedish isolate of a tubular beet virus (86-109) or a belgian isolate of a similar virus (1530) were compared following separation on non-denaturing polyacrylamide gels. the dsrnas of bnyvv differed in mobility from those isolated from tissue infected with the other four tubular b ... | 1992 | 1588330 |
| assessment of concentrations of beet necrotic yellow vein virus by enzyme-linked immunosorbent assay. | a quantitative screening method based on enzyme-linked immunosorbent assay (elisa) was developed for beet necrotic yellow vein virus (bnyvv). with respect to the assessment of the dose-response curve, the response-error relation, and the precision profile the choice of concentrations and replications per concentration was investigated. special attention was given to control and fulfillment of validity assumptions as formulated by finney (1978). to this end the influence of the dilution medium fo ... | 1992 | 1597507 |
| effect of recombinant beet necrotic yellow vein virus with different rna compositions on mechanically inoculated sugarbeets. | beet necrotic yellow vein virus (bnyvv) inocula with different rna compositions were prepared from infectious transcripts of rnas 3 and 4 and the rg 1 isolate, which has a genome consisting only of rnas 1 and 2. the recombinant viruses were inoculated on 6- to 8-day-old sugarbeet seedlings by 'vortexing'. inocula containing rnas 1 and 2 or 1, 2 and 4 produced some growth reduction, but the most dramatic effects, with yield reductions of about 95% in a highly susceptible variety, were seen when r ... | 1991 | 1895061 |
| cdnas of beet necrotic yellow vein virus rnas 3 and 4 are rendered biologically active in a plasmid containing the cauliflower mosaic virus 35s promoter. | cdnas of beet necrotic yellow vein virus rnas 3 and 4 could be rendered biologically active when they were placed under the control of the cauliflower mosaic virus 35s promoter and polyadenylation signal. although the 35s in vivo transcripts should have contained up to forty 5' and several hundred 3' nonviral nucleotides, the progeny viral rnas had the same sizes as in naturally infected sugarbeets. the progeny rnas did not hybridize with the nonviral sequences indicating that they were apparent ... | 1991 | 1926790 |
| immunodetection in vivo of beet necrotic yellow vein virus-encoded proteins. | open reading frames identified on the four genomic rnas of beet necrotic yellow vein virus were cloned into bacterial expression vectors and resulting cl-fusion proteins expressed in escherichia coli were used to raise polyclonal antibodies. this set of antisera was used to show the presence of 7 of 9 predicted viral proteins in mechanically inoculated chenopodium quinoa leaves by the western blot technique. viral coat protein (p22) and its readthrough protein p85 encoded by rna-2 could be detec ... | 1990 | 2202150 |
| antigenic analysis of the coat protein of beet necrotic yellow vein virus by means of monoclonal antibodies. | by means of monoclonal antibodies (mabs), five (groups of) epitopes were identified on particles of beet necrotic yellow vein virus (bnyvv). epitopes 1 and 2, which were located on the opposite extremities of virus particles, are discontinuous (sds-labile) epitopes which were destroyed when the particles were treated with trypsin. epitope 3 is a continuous (sds-stable) epitope located at the same extremity as epitope 2. it was not destroyed when the particles were treated with trypsin and was pr ... | 1990 | 2230729 |
| multiplication of beet necrotic yellow vein virus rna 3 lacking a 3' poly(a) tail is accompanied by reappearance of the poly(a) tail and a novel short u-rich tract preceding it. | beet necrotic yellow vein virus rnas 1 and 2 but not rnas 3 and 4 are required for viral multiplication in chenopodium quinoa leaves. elimination of the 3' poly(a) tail from rna 3 transcripts markedly attenuated their ability to be amplified when co-inoculated with rnas 1 and 2 to this host. successful multiplication of the tailless rna 3 was accompanied by the reappearance of new 3' poly(a) tails on the progeny. the evidence suggests that the newly acquired poly(a) sequence results from the act ... | 1990 | 2389554 |
| probable reassortment of genomic elements among elongated rna-containing plant viruses. | the relationships of genome organization among elongated (rod-shaped and filamentous) plant viruses have been analyzed. sequences in coding and noncoding regions of barley stripe mosaic virus (bsmv) rnas 1, 2, and 3 were compared with those of the monopartite rna genomes of potato virus x (pvx), white clover mosaic virus (wclmv), and tobacco mosaic virus, the bipartite genome of tobacco rattle virus (trv), the quadripartite genome of beet necrotic yellow vein virus (bnyvv), and icosahedral trico ... | 1989 | 2504930 |
| comparison of enzyme-linked immunosorbent assay (elisa) with dot hybridization using 32p- or 2-acetylaminofluorene (aaf)-labelled cdna probes for the detection and characterization of beet necrotic yellow vein virus. | beet necrotic yellow vein virus (bnyvv) was detected by enzyme-linked immunosorbent assay (elisa) and rna/dna dot hybridization using either radiolabelled or non-radioactive probes. dot hybridization specifically distinguished isolates that could not be distinguished by elisa. the detection thresholds for elisa, hybridization with non-radioactive probes and hybridization with radiolabelled probes were 2 ng, 0.2 ng, 0.02 ng of purified virus, respectively. dot hybridization with non-radioactive p ... | 1989 | 2671680 |
| in vitro synthesis of biologically active beet necrotic yellow vein virus rna. | beet necrotic yellow vein virus (bnyvv) has a quadripartite plus-strand rna genome in which the two smallest genome components, rna 3 and 4, are not necessary for virus multiplication in leaves. infectious transcripts of bnyvv rna 3 and 4 have already been described (v. ziegler-graff, s. bouzoubaa, i. jupin, h. guilley, g. jonard, and k. richards (1988) j. gen. virol. 69, 2347-2357). in this paper we describe synthesis of a full-length rna-1 transcript by bacteriophage t7 rna polymerase-directed ... | 1989 | 2773320 |
| effect of beet necrotic yellow vein virus rna composition on transmission by polymyxa betae. | beet necrotic yellow vein virus (bnyvv) is naturally transmitted by the soil-borne fungus polymyxa betae and usually remains confined to the roots of infected sugarbeets. in naturally infected sugarbeets the virion rna always consists of four components which are uniform in size in different isolates but when bnyvv is propagated by mechanical inoculation to leaves of chenopodium quinoa the two smallest rna components, rna-3 and -4, may undergo deletion or disappear from the isolate, suggesting t ... | 1988 | 3336941 |
| the complete nucleotide sequence of the potexvirus white clover mosaic virus. | the complete nucleotide sequence (5845 nucleotides) of the genomic rna of the potexvirus white clover mosaic virus (wc1mv) has been determined from a set of overlapping cdna clones. forty of the most 5'-terminal nucleotides of wc1mv showed homology to the 5' sequences of other potexviruses. the genome contained five open reading frames which coded for proteins of mr 147, 417, mr 26,356, mr 12,989, mr 7,219 and mr 20,684 (the coat protein). the mr 147,417 protein had domains of amino acid sequenc ... | 1988 | 3340527 |
| the complete nucleotide sequence of potato virus x and its homologies at the amino acid level with various plus-stranded rna viruses. | double-stranded cdna of potato virus x (pvx) genomic rna has been cloned and sequenced. the sequence [6435 nucleotides excluding the poly(a) tract] revealed five open reading frames (orfs) which were numbered one to five starting at the 5' terminus of the rna. they encoded proteins of mr 165588 (166k), 24622 (25k), 12324 (12k), 7595 (8k) and 25080 (coat protein), respectively. orfs 1 and 2 were inphase coding regions. the orf 1 product contained domains of homology with the tobacco mosaic virus ... | 1988 | 3404114 |
| detection of beet necrotic yellow vein virus using reverse transcription and polymerase chain reaction. | a diagnostic test based on reverse transcription followed by the polymerase chain reaction (rt-pcr) was developed for the detection of beet necrotic yellow vein virus (bnyvv). a specific 500-base-pair fragment was amplified from the read-through region of the coat protein gene located on rna-2. the viral origin of the amplified product was confirmed by sequencing, with the sequence obtained having 94.5% homology with published sequence data for bnyvv. the assay gave a sensitivity of 800 times th ... | 1995 | 7559854 |
| detection of beet necrotic yellow vein virus strains, variants and mixed infections by examining single-strand conformation polymorphisms of immunocapture rt-pcr products. | single-strand conformation polymorphism analysis was found to be a powerful tool for rapidly assigning large numbers of beet necrotic yellow vein virus (bnyvv) isolates to a known strain group as well as for detecting mixed infections, minor variants or new strain groups. the prevalence of the b-type in germany and france and the a-type in most other countries was confirmed. minor variants with a very restricted distribution were detected occasionally. new rhizomania outbreaks in great britain w ... | 1995 | 7636486 |
| primary structure and sequence analysis of rna2 of a mechanically transmitted barley mild mosaic virus isolate: an evolutionary relationship between bymo- and furoviruses. | the rna2 nucleotide sequence of a mechanically transmitted isolate of barley mild mosaic virus (bammv) has been determined. a combination of northern blot and sequence analysis indicates that this rna2 lacks approximately 1000 nucleotides of its c-terminal protein (p2) gene, with respect to polymyxa graminis transmitted bammv. this is confirmed by sequence comparison with rna2 of a fungus transmitted bammv isolate, which reveals the presence of a single deletion located in the 3'-terminal part o ... | 1995 | 7710357 |
| [beet necrotic yellow vein virus transmitted by the fungus polymyxa betae]. | | 1994 | 7856119 |
| in situ localization of the non-structural protein p25 encoded by beet necrotic yellow vein virus rna 3. | the in situ localization of the non-structural protein p25 encoded by beet necrotic yellow vein virus (bnyvv) rna 3 and of the bnyvv coat protein (cp) was studied by immunoelectron microscopy in infected leaf and root cells of chenopodium murale and c. quinoa. the cp was detected in the cytoplasm of all cell types except xylem, sieve elements, and companion cells. p25 was detected in the cytoplasm and nuclei of the same cell types. the intensity of cp labelling varied depending upon the stage of ... | 1995 | 7897353 |
| restriction fragment length polymorphism analysis of reverse transcription-pcr products reveals the existence of two major strain groups of beet necrotic yellow vein virus. | beet necrotic yellow vein virus (bnyvv)-infected sugarbeets were obtained from many parts of europe and also from some sites in asia and the u.s.a. reverse transcription (rt)-pcr products of more than 1 kbp were obtained for four different regions of the viral genome which may be particularly important with respect to the pathogenic properties of the virus, i.e. for the coat protein and the 42k protein-encoding regions on rna 2 and for major parts of rnas 3 and 4. restriction fragment length pol ... | 1994 | 7913953 |
| the nucleotide sequence of potato mop-top virus rna 2: a novel type of genome organization for a furovirus. | particles of isolate t of potato mop-top furovirus (pmtv) contain three rna species (6.5, 3.0 and 2.5 kb). hybridization tests with cloned cdna probes showed that none of these species was derived from another. rna 2 (2962 nt), which was sequenced, has non-coding regions of 368 nt and 285 nt at the 5' end and 3' end, respectively. near the 5' terminus, nucleotides 46 to 110 are able to form a stem-loop structure, the stem of which has 23 bp with only one mismatch and one unpaired nucleotide. fro ... | 1994 | 7996148 |
| artificial defective interfering rnas derived from rna 2 of beet necrotic yellow vein virus. | long internal deletions were introduced into cloned cdna of beet necrotic yellow vein virus rnas 1-4 and transcripts containing the deletions were tested for their ability to inhibit replication of viral rna in chenopodium quinoa protoplasts and plants. no inhibition was observed with the deletion mutants based on rnas 1, 3 and 4 but the rna 2 deletion mutants all provoked a dramatic inhibition of synthesis of viral rnas 1 and 2. | 1994 | 8198439 |
| the cloning and sequencing of coat protein gene from beet necrotic yellow vein virus. | the beet necrotic yellow vein virus (bnyvv) isolate nm was isolated from sugarbeet infected with rhizomania in inner mongolia of china. the cdna of bnyvv coat protein (cp) gene was amplified from the extracted rna of bnyvv isolate nm by using the polymerase chain reaction (pcr) and cloned into pgem-7zf(+). its complete nucleotide sequence was determined by means of sanger's dideoxy-mediated chain-termination method. the result shows that cp gene of bnyvv isolate has 567 nucleotides. it shares 98 ... | 1993 | 8199322 |
| complete nucleotide sequence and organization of the bipartite rna genome of soil-borne wheat mosaic virus. | the complete nucleotide sequences of rnas 1 and 2 of soil-borne wheat mosaic virus (sbwmv), type member of the furovirus group, were determined. rna 1 is 7099 nucleotides (nt) and encodes a 150-kda protein from the 5' end region, the uga termination codon of which can be partially read through to produce a 209-kda protein, and a 37-kda protein in the 3' end region. the c-terminal region of the 150-kda protein contains an ntp-binding helicase motif and the readthrough region, an rna polymerase mo ... | 1993 | 8317092 |
| the secondary structure of the 5'-noncoding region of beet necrotic yellow vein virus rna 3: evidence for a role in viral rna replication. | secondary structure-sensitive chemical and enzymatic probes have been used to produce a model for the folding of the first 312 residues of the long 5'-noncoding region of beet necrotic yellow vein virus rna 3. the structure consists of two major domains, one of which includes long distance base-pairing interactions between two short sequence elements (box i and box ii) situated between positions 237 and 292 and complementary elements (box i' and ii') near the 5'-terminus. previous studies have s ... | 1993 | 8464729 |
| beet necrotic yellow vein virus 42 kda triple gene block protein binds nucleic acid in vitro. | the triple gene block (tgb) of beet necrotic yellow vein virus rna 2 is required for cell-to-cell movement of the virus rna. the protein p42 encoded by the 5'-proximal gene of the tgb has consensus sequence motifs characteristic of an atp/gtp-dependent helicase. p42 was over-expressed in escherichia coli and shown to bind both single- and double-stranded rna and dna by northwestern blotting. site-directed mutagenesis located the nucleic acid-binding domain to the n-terminal 24 amino acids of the ... | 1996 | 8609485 |
| beet soil-borne virus rna 3--a further example of the heterogeneity of the gene content of furovirus genomes and of triple gene block-carrying rnas. | the complete nucleotide sequence of rna 3 of the ahlum isolate of beet soil-borne virus (bsbv) was determined from cdnas obtained with immunocaptured virus particles and denatured preparations of dsrna. bsbv rna 3 is unique among the plant virus rnas studied so far in containing apparently only the coding sequences of a triple gene block (tgb). the derived amino acid sequences of the three putative tgb-encoded proteins showed the highest level of sequence similarities with those of the correspon ... | 1996 | 8614988 |
| nucleotide sequence analysis of rna-5 of five isolates of beet necrotic yellow vein virus and the identity of a deletion mutant. | the nucleotide sequences of rna-5 from two laboratory isolates (d-5 and d-6) and three field isolates (sh1, s43 and r83) of beet necrotic yellow vein virus (bnyvv) were determined. isolates d-5 and d-6, derived from a d field culture during mechanical inoculation, contained rna-5 of molecular size 1.4 kb and 1.0 kb, respectively. the sequences of d-5 sh1, s43 and r83 were found to be at least 98% identical and from 1342 to 1347 nucleotides in length, excluding the poly(a) tail. each contained a ... | 1996 | 8627244 |
| immunodetection of beet necrotic yellow vein virus rna3-encoded protein in different host plants and tissues. | the protein p25 open reading frame (orf) of beet necrotic yellow vein virus-bnyvv rna3 was cloned into bacterial expression vector downstream of the 5-'terminus part of beta-galactosidase orf and the expressed p25 fusion protein was used to produce an antiserum. the latter was employed to detect the subcellular location of p25 in mechanically inoculated tetragonia expansa, chenopodium quinoa and sugarbeet leaves by western blot assay. the results showed that p25 was present as a soluble protein ... | 1996 | 8886114 |
| expression of single-chain antibody fragments (scfv) specific for beet necrotic yellow vein virus coat protein or 25 kda protein in escherichia coli and nicotiana benthamiana. | the coding sequences for the variable regions of heavy and light chains of monoclonal antibodies (mabs) to beet necrotic yellow vein virus (bnyvv) coat protein (cp) or the 25 kda nonstructural protein (p25) were cloned into the pcock vector and expressed as single-chain antibody fragments (scfv) in escherichia coli. for expression in higher plants the scfv were targeted either to the secretory pathway by including the sequences encoding the pectate lyase b (pelb) or the phytohemagglutinin (pha) ... | 1996 | 8980548 |
| evidence for in vitro and in vivo autocatalytic processing of the primary translation product of beet necrotic yellow vein virus rna 1 by a papain-like proteinase. | beet necrotic yellow vein virus rna 1 contains a single long orf corresponding to the theoretical translation product of 237 kda which contains the information necessary for replication of the viral genome. this orf contains a putative papain-like proteinase domain which has been localized, on the basis of sequence alignments, between the helicase and polymerase domains. here we show that the rna 1 primary translation product can be cleaved autocatalytically in vitro into two species of 150 kda ... | 1997 | 9191870 |
| single-chain fv fusion proteins suitable as coating and detecting reagents in a double antibody sandwich enzyme-linked immunosorbent assay. | a recombinant enzyme-linked immunosorbent assay (elisa) system, entirely based on antibody fragments, is described here as an attractive alternative to assays using polyclonal antisera or monoclonal antibodies. two expression vectors have been developed for cloning and production of single-chain fv (scfv) fusion proteins suitable as coating and detecting reagents, respectively, in a highly sensitive double antibody sandwich elisa. the coating reagent is produced from the vector pzip1, as a bival ... | 1997 | 9212874 |
| vascular movement of beet necrotic yellow vein virus in beta macrocarpa is probably dependent on an rna 3 sequence domain rather than a gene product. | rnas 1 and 2 of beet necrotic yellow vein virus (bnyvv) carry the functions enabling viral rna replication, cell-to-cell movement, virus assembly and vascular movement of the virus in the systemic host spinacea oleracea. in beta macrocarpa, on the other hand, bnyvv rna 3 is required for vascular movement. replication-competent rna 3 transcripts carrying various point mutations and deletions were coinnoculated with rnas 1 and 2 to young leaves of b. macrocarpa and the ability of the virus to mult ... | 1998 | 9472625 |
| cell-to-cell movement of beet necrotic yellow vein virus: i. heterologous complementation experiments provide evidence for specific interactions among the triple gene block proteins. | cell-to-cell movement of beet necrotic yellow vein virus (bnyvv) requires three proteins encoded by a triple gene block (tgb) on viral rna 2. a bnyvv rna 3-derived replicon was used to express movement proteins to functionally substitute for the bnyvv tgb proteins was tested by coinoculation of tgb-defective bnyvv with the various replicons to chenopodium quinoa. trans-heterocomplementation was successful with the movement protein (p30) of tobacco mosaic virus but not with the tubule-forming mov ... | 1998 | 9650295 |
| nicotiana benthamiana plants expressing beet necrotic yellow vein virus (bnyvv) coat protein-specific scfv are partially protected against the establishment of the virus in the early stages of infection and its pathogenic effects in the late stages of infection. | transgenic plants of nicotiana benthamiana expressing single chain antibody fragments (scfv) specific for the coat protein of beet necrotic yellow vein virus (bnyvv) and non-expressing control plants were inoculated with bnyvv mechanically and by means of the vector polymyxa betae. the scfv were presumably expressed in the endoplasmic reticulum (er). the average time needed for infections to become detectable was longer in the scfv-expressing plants than in the non-expressing control plants. in ... | 1997 | 9672643 |
| the genome organization of the broad bean necrosis virus (bbnv). | the genome of the broad bean necrosis virus oita-isolate (bbnv-o) [rna1 (6.0 kb), rna2 (2.8 kb) and rna3 (2.4 kb)] was cloned and sequenced. computer analysis indicates that methyltransferase, helicase and rna-dependent rna polymerase (rdrp) motifs are present in rna1. the viral capsid protein (cp) cistron is located at the 5' terminal end of rna2 and the mr of cp (20 k) is close to that determined by sds-page analysis. an ochre codon (uaa) in the cp cistron is thought to be partially suppressed ... | 1998 | 9722878 |
| evidence for three groups of sequence variants of beet necrotic yellow vein virus rna 5. | about half of japanese isolates of beet necrotic yellow vein virus (bnyvv) were found to contain rna 5 molecules, which were also detected in virus isolates from china and france. sequence comparisons of rna 5 (nucleotides 327 to 1171) in 25 isolates showed that there are up to 8% sequence differences, and that rna 5 variants fall into three groups: group i contains most of the japanese and chinese isolates, group ii two japanese isolates, and group iii four french isolates. the group i isolates ... | 1999 | 10416372 |
| improved detection of beet necrotic yellow vein virus in a das elisa by means of antibody single chain fragments (scfv) which were selected to protease-stable epitopes from phage display libraries. | the detection of beet necrotic yellow vein virus (bnyvv) in stored sugar beets by means of monoclonal antibodies or antibody single chain fragments (scfv) often poses problems, because the immunodominant c-terminal epitope of the viral coat protein is readily lost due to proteolysis. clones which produce scfv specific for protease-stable bnyvv epitopes were selected from two naive phage display libraries. fusion proteins of the scfv with a human igg kappa chain (expressed from the newly designed ... | 2000 | 10664416 |
| detection and nucleotide analysis of rna5 of beet necrotic yellow vein virus isolated in china. | using the rt-pcr method, five isolates of beet necrotic yellow vein virus from china were used for the rna5 genomic component detection and sequence analysis. the result showed that rna5 was only found in the isolates from baotou and hohhot, but not in those of xingjiang, helongjiang, and wulate of inner mongolia. the rna5 components had 1338 nucleotides and 1358 nucleotides in the length of baotou and hohhot isolates, respectively, in which the single open reading frame (orf) encoding for a pro ... | 1999 | 11037951 |
| effects of structural modifications upon the accumulation in planta of replicons derived from beet necrotic yellow vein virus rna 3. | beet necrotic yellow vein virus (bnyvv) rna 3 from which all but the 3' and 5' 'core' replication origins (promoters) have been deleted replicates when coinoculated to chenopodium quinoa with viral rnas 1 and 2. the resulting 'replicon' can be used to express inserted heterologous sequences in planta. the effects of alterations of replicon structure on its efficiency of accumulation in planta were examined. inclusion of up to approximately 240 nucleotides of sequence from the region immediately ... | 1999 | 10446653 |
| detection and characterization of a distinct type of beet necrotic yellow vein virus rna 5 in a sugarbeet growing area in europe. | a fifth beet necrotic yellow vein virus (bnyvv) rna species has been detected in europe in sugarbeet infected with p-type bnyvv. very little sequence variation was found between two european sources of this rna 5*, but considerable differences were detected between these two european sources on the one hand and the four japanese sources recently analysed by kiguchi et al. on the other. the bnyvv rna 5-encoded 26 k proteins share a stretch of six amino acids (frgpgn) with the bnyvv rna 3-encoded ... | 1997 | 9267459 |
| complete nucleotide sequence of the japanese isolate s of beet necrotic yellow vein virus rna and comparison with european isolates. | the complete nucleotide sequences of beet necrotic yellow vein virus rna-1 to rna-4 of the japanese isolate s (bnyvv-s) were determined and compared with those of french isolate (bnyvv-f2). the nucleotide sequences of the two isolates were very similar, differing by only 1.7% (rna-1), 4.1% (rna-2), 2.9% (rna-3) and 3.6% (rna-4), respectively. the differences of the amino acid sequences of the two isolates depended upon the open reading frames (orf) as follows: p237, 1.4%; p22 (coat protein), 2.1 ... | 1996 | 8973531 |
| highly sensitive immunoassays for detection of barley stripe mosaic virus and beet necrotic yellow vein virus. | enzyme immunoassays based on the use of monoclonal antibodies (mabs) were developed for the detection of the barley stripe mosaic virus (bsmv) and the beet necrotic yellow vein virus (bnyvv). assays employing conjugates of mabs to horseradish peroxidase (hrp) were compared to systems with biotinylated mabs and streptavidin conjugated either to monomeric hrp or to hrp homopolymers with different polymerisation degrees including those of 20, 40 and 80. in the elisa with streptavidin-polymeric hrp ... | 1996 | 8882650 |
| high resolution analysis of the readthrough domain of beet necrotic yellow vein virus readthrough protein: a kter motif is important for efficient transmission of the virus by polymyxa betae. | the 5'-terminal cistron of beet necrotic yellow vein furovirus rna 2 encodes the 21 kda major viral coat protein and terminates with an amber stop codon which can undergo suppression to give rise to a 75 kda readthrough (rt) protein referred to as p75. p75 is a minor component of virions and the 54 kda rt domain following the coat protein sequence is important both for virus assembly and transmission by the fungal vector polymyxa betae. to better define the regions of the rt domain involved in t ... | 1996 | 8757975 |
| cdna cloning and sequencing of 54kda fragment of the 75kda readthrough protein gene from beet necrotic yellow vein virus. | with viral rna extracted from purified beet necrotic yellow vein virus (bnyvv) isolated from inner mongolia, the first strand of cdna encoding a 54kda fragment of the 75kda readthrough protein on the rna2 was synthesized by reverse transcription. a double-strand cdna fragment of 1.5 kb was obtained after 30 cycles of pcr amplification. the fragment was ligated into and mapped on pgem-7zf(+). the result of sequence analysis shows that the 54kda readthrough domain is 1509 nucleotides (nt). compare ... | 1995 | 8562847 |
| complete nucleotide sequence and genome organization of beet soilborne mosaic virus, a proposed member of the genus benyvirus. | the complete nucleotide sequences of rnas 1 to 4 of beet soilborne mosaic virus (bsbmv) were determined. the genomic organization of bsbmv is identical to beet necrotic yellow vein virus (bnyvv), the type species of the genus benyvirus. bsbmv rna1 encodes a single large open reading frame (orf) with similar replicase-associated motifs identified for bnyvv. bsbmv rna2 has six potential orfs with an organization resembling bnyvv rna2. rna3 and rna4 resemble the analogous bnyvv rnas, which encode p ... | 2001 | 11811691 |
| multiplex reverse transcription-pcr for simultaneous detection of beet necrotic yellow vein virus, beet soilborne virus, and beet virus q and their vector polymyxa betae keskin on sugar beet. | three soilborne viruses transmitted by polymyxa betae keskin in sugar beet have been described: beet necrotic yellow vein virus (bnyvv), the agent of rhizomania, beet soilborne virus (bsbv), and beet virus q (bvq). a multiplex reverse transcription-pcr technique was developed to simultaneously detect bnyvv, bsbv, and bvq, together with their vector, p. betae. the detection threshold of the test was up to 128 times greater than that of an enzyme-linked immunosorbent assay. systematic association ... | 2003 | 12676720 |
| detection by immunogold labelling of p75 readthrough protein near an extremity of beet necrotic yellow vein virus particles. | rna 2 of beet necrotic yellow vein virus carries the cistron for the 21 kd coat protein at its 5'-extremity. during translation, the coat protein cistron termination codon is suppressed about 10% of the time so that translation continues into the adjacent open reading frame to produce a 75 kd species, known as p75, which contains the coat protein sequence at its n-terminus. immunoblotting experiments with a p75-specific antiserum showed that p75 is present in only trace amounts in purified virus ... | 1994 | 8279955 |
| mapping the promoter for subgenomic rna synthesis on beet necrotic yellow vein virus rna 3. | during infection of tetragonia expansa leaves, rna 3 of the quadripartite genome of beet necrotic yellow vein virus directs synthesis of a subgenomic rna (rna 3sub) which corresponds to the 3'-terminal 600 residues of the rna 3 molecule. biologically active run-off transcripts have been prepared from full-length cdna of rna 3 cloned behind a bacteriophage t7-rna polymerase promoter. rna 3 transcripts carrying deletions in the vicinity of the rna 3sub initiation site were produced by site-directe ... | 1993 | 8268252 |
| strategies for the detection of potential beet necrotic yellow vein virus genome recombinations which might arise as a result of growing a type coat protein gene-expressing sugarbeets in soil containing b type virus. | we have searched for beet necrotic yellow vein virus (bnyvv) populations with a recombined genome which could possibly arise when transgenic sugarbeets expressing the coat protein gene of a type bnyvv are grown in soil containing polymyxa betae carrying b type bnyvv, in soil samples from previous field release experiments and in a greenhouse model experiment. in order to accelerate the potential evolution of virus populations with recombined genomes in the model experiment, eight successive crop ... | 2004 | 15070072 |
| in situ localisation of beet necrotic yellow vein virus (bnyvv) in rootlets of susceptible and resistant beet plants. | mechanisms of resistance to beet necrotic yellow vein virus (bnyvv) were studied by comparing the multiplication and distribution of bnyvv in root tissue of some beet accessions. seedlings were infected either by soil containing resting spores of polymyxa betae with bnyvv, or by a viruliferous zoospore suspension. with both inoculation methods high virus concentrations were obtained in rootlets of the susceptible cultivar 'regina'. using infested soil, low virus concentrations were found in the ... | 1994 | 8031238 |
| expression of multiple foreign epitopes presented as synthetic antigens on the surface of potato virus x particles. | we describe the construction of recombinant potato virus x (pvx) vectors expressing two different epitopes, ep4 and ep6, from beet necrotic yellow vein virus (bnyvv). the seven-amino-acid epitopes were expressed as n-terminal coat protein fusions and were displayed on the surface of pvx particles. particle assembly into full virions was successful even though no wild type coat protein subunits were present, and the epitopes could be detected in crude extracts and purified virus preparations with ... | 2005 | 15503224 |
| evidence for presence of types a and b of beet necrotic yellow vein virus (bnyvv) in iran. | rhizomania a viral disease, caused by beet necrotic yellow vein benyvirus (bnyvv), is now widely spread, throughout the sugar beet growing areas of iran. genomes of bnyvv are composed of five rna molecules with specific functions. in this study sequence analyses were conducted on the major coat protein gene (cp21), and parts of rna3 and rna4 of an iranian strain of bnyvv from the fars province. sequence alignments of iran fars cp21 with other isolates showed closed similarities at nucleotide and ... | 2004 | 15550776 |
| complete nucleotide sequence of peanut clump virus rna 1 and relationships with other fungus-transmitted rod-shaped viruses. | the complete nucleotide sequence of rna 1 of the tentative furovirus peanut clump virus (pcv) has been determined by characterization of cloned cdna and by direct rna sequencing. the sequence is 5897 nucleotides in length and contains three long open reading frames (orfs). the 5'-terminal proximal orf has the potential to encode a polypeptide of m(r) 130942 (p131) containing methyltransferase and rna helicase homologous domains and displaying homology with large nonstructural proteins of alpha-l ... | 1994 | 7964624 |
| the small cysteine-rich protein p14 of beet necrotic yellow vein virus regulates accumulation of rna 2 in cis and coat protein in trans. | the effect of null mutations of the small cysteine-rich protein p14 encoded by rna 2 of beet necrotic yellow vein virus has been investigated using in vitro transcripts of viral rna to infect chenopodium quinoa protoplasts. the p14 mutations down-regulated rna 2 accumulation by approximately 10- to 50-fold. accumulation of minus-strand rna 2 was also diminished but rna 1 accumulation was much less affected. the inhibition of rna 2 accumulation could not be complemented in trans by providing p14 ... | 1995 | 7793082 |
| a multiplex rt-pcr assay capable of distinguishing beet necrotic yellow vein virus types a and b. | a multiplex reverse-transcription polymerase chain assay (mrt-pcr) was developed, based on primers designed to distinguish the a and b types of beet necrotic yellow vein virus (bnyvv). rna was extracted from 72 bnyvv isolates from asia, europe and north america, and the type of each isolate determined using an established detection method based on single strand conformation polymorphisms (sscps). an area of the 'triple gene block' region on rna 2 was amplified and sequenced from 16 isolates of t ... | 2004 | 15664049 |
| comparison of the beet necrotic yellow vein virus p75 nucleotide sequences of belgian type a and type b sources. | rna-2 p75 open reading frame sequencing was conducted on bnyvv-infected sugar beet plants originating from 10 belgian sources and was compared with sequences originating from france, kazakhstan, japan and china. this allowed the characterization of types a and b in belgium. sequence analysis confirmed that type a is intermediate between types p and b. the analysis of nucleotide sequences of the capsid protein epitopes and of different motifs involved in the transmission of the virus to the plant ... | 2005 | 15681050 |
| pcr and non-isotopic labeling techniques for plant virus detection. | pcr technology permits the detection of viruses at levels several orders of magnitude lower than is possible by other methods. this high sensitivity facilitates detection of virus sequences during the early stages of infection of plants and in soil and vector samples. early detection of beet necrotic yellow vein virus (bnyvv) in beta vulgaris is an important part of the strategy for prevention of the spread of rhizomania, a commercially significant disease of sugar beet. a diagnostic test for bn ... | 1995 | 7580844 |
| evidence that rna silencing-mediated resistance to beet necrotic yellow vein virus is less effective in roots than in leaves. | in plants, rna silencing is part of a defense mechanism against virus infection but there is little information as to whether rna silencing-mediated resistance functions similarly in roots and leaves. we have obtained transgenic nicotiana benthamiana plants encoding the coat protein readthrough domain open reading frame (54 kda) of beet necrotic yellow vein virus (bnyvv), which either showed a highly resistant or a recovery phenotype following foliar rub-inoculation with bnyvv. these phenotypes ... | 2005 | 15782633 |
| construction and expression of 75kda readthrough protein gene from beet necrotic yellow vein virus. | using dna recombinant techniques, coat protein (cp) gene and 54kda fragment from beet necrotic yellow vein virus (bnyvv) rna2 were ligated to construct 75kda readthrough protein gene. comparing with wild-type 75kda readthrough protein gene, four nucleotides of the constructed gene were replaced, including cp amber termination codon uag to aug. correspondingly, two amino acids were changed. the temperature inducible expression vectors containing 75kda readthrough protein gene or its 54kda fragmen ... | 1995 | 7548774 |
| sequence divergence of four soilborne sugarbeet-infecting viruses. | soilborne viruses are among the most harmful pathogens of sugarbeet (beta vulgaris l.ssp. vulgaris) but most of them lack information on genetic variability due to paucity of sequence data. only one isolate of beet soil borne virus (bsbv; genus pomovirus), beet virus q (bvq; genus pomovirus) and beet soil borne mosaic virus (bsbmv; genus benyvirus) has been characterised for the coat protein (cp) gene. in this study, the cp gene sequences of three isolates each of bsbv and beet necrotic yellow v ... | 2005 | 15965609 |
| location, size, and complexity of epitopes on the coat protein of beet necrotic yellow vein virus studied by means of synthetic overlapping peptides. | five regions on the coat protein of bnyvv which had been shown previously to be involved in the formation of continuous epitopes were further analyzed by means of synthetic overlapping peptides. it was found that at least some of these regions may encompass several overlapping epitopes (or parts thereof). four monoclonal antibodies (mabs) which were known to be specific for the c-terminus of bnyvv coat protein (amino acids 182-188 = rtsppgq) were found to react with different sets of peptides wh ... | 1994 | 7505070 |
| mapping sequences required for productive replication of beet necrotic yellow vein virus rna 3. | of the four genome components of beet necrotic yellow vein virus only rnas 1 and 2 are essential for viral replication in leaves. we have mapped cis-regulatory elements on rna 3 by introducing deletions into expressible cdna clones and inoculating leaves with the altered transcripts along with rnas 1 and 2. transcripts carrying internal deletions extending to within 69 residues of the 3' poly(a) tail or to within about 300 residues of the 5' terminus were efficiently amplified and encapsidated i ... | 1990 | 2389553 |
| phylogenetic analysis of isolates of beet necrotic yellow vein virus collected worldwide. | a study of molecular diversity was carried out on 136 sugar beets infected with beet necrotic yellow vein virus (bnyvv, benyvirus) collected worldwide. the nucleotide sequences of the rna-2-encoded cp, rna-3-encoded p25 and rna-5-encoded p26 proteins were analysed. the resulting phylogenetic trees allowed bnyvv to be classified into groups that show correlations between the virus clusters and geographic origins. the selective constraints on these three sequences were measured by estimating the r ... | 2005 | 16186246 |
| inoculation of sugar beet protoplasts with beet necrotic yellow vein virus particles by mild sonication. | a novel procedure employing mild sonication for in vitro inoculation of plant protoplasts with virus particles has been established. sugar beet (beta vulgaris l.) protoplasts were briefly exposed to 20 khz ultrasound in the presence of beet necrotic yellow vein virus (bnyvv) particles. the accumulation of bnyvv coat protein was analyzed by an enzyme-linked immunosorbent assay. the infection was detectable after 16 h and reached maximum 3-3 1/2 days after inoculation. maximum levels of bnyvv coat ... | 1990 | 2211957 |
| shortened forms of beet necrotic yellow vein virus rna-3 and -4: internal deletions and a subgenomic rna. | beet necrotic yellow vein virus rna-3 and rna-4, produced as full-length biologically active transcripts in vitro, can undergo spontaneous internal deletions when inoculated onto chenopodium quinoa leaves along with rna-1 and -2. the deletion process is specific, giving rise to only a few major species, and can be rapid; deleted forms appear after only one or two passages in leaves. in one of the shortened forms of rna-4, the deletion precisely eliminated one copy of a 15 nucleotide (nt) direct ... | 1991 | 1993870 |
| zygocactus virus x-based expression vectors and formation of rod-shaped virus-like particles in plants by the expressed coat proteins of beet necrotic yellow vein virus and soil-borne cereal mosaic virus. | expression vectors were constructed from 35s promoter-containing full-length cdna clones of zygocactus virus x (zvx). the expression of foreign genes was driven by the zvx coat protein (cp) subgenomic promoter. it was successful only when the variable region downstream of the conserved putative promoter region gsttaagtt(x(12-13))gaa was retained. most of the zvx cp gene, except for a short 3' part, was replaced by the corresponding sequence of the related schlumbergera virus x (svx) and its cp s ... | 2006 | 16432032 |
| occurrence of two different types of rna-5-containing beet necrotic yellow vein virus in the uk. | two types of rna-5-containing beet necrotic yellow vein virus (bnyvv) have been detected in the uk at different sites in norfolk. on the basis of nucleotide (nt) sequence comparisons, one virus source (uk-mh) was clearly identified as p type bnyvv, a virus type that had previously only been detected in two widely separated parts of the world, france and kazakhstan. the other virus source (uk-ff) has a complex genome composition. the analysed portions of its rnas 2 and 4 are closely related to th ... | 2007 | 16941060 |
| genetic stability of recombinant potato virus x virus vectors presenting foreign epitopes. | we investigated the genetic stability of recombinant potato virus x vectors presenting beet necrotic yellow vein virus (bnyvv) epitopes. following n-terminal pvx coat protein (cp) fusion of the bnyvv epitopes, we inoculated nicotiana benthamiana plants with recombinant (r)pvx and carried out five serial passages through systemically-infected plants. rt-pcr investigation of the bnyvv epitope sequences revealed the accumulation of several point mutations and deletions, predominantly affecting posi ... | 2007 | 17216135 |
| evidence that the 75k readthrough protein of beet necrotic yellow vein virus rna-2 is essential for transmission by the fungus polymyxa betae. | two mutant strains of beet necrotic yellow vein virus (bnyvv) containing deletion mutants of rna-2 were produced during serial passage in mechanically inoculated tetragonia expansa leaves. the mutant strains were referred to as s-0a (rna-1 + 2a) and g-0b (rna-1 + 2b). rna-2a and rna-2b were about 4.3 kb and 4.2 kb in length, respectively, whereas normal sized rna-2 was about 4.8 kb in length. in vitro translation and immunoblot analysis showed that rna-2, rna-2a and rna-2b all directed synthesis ... | 1991 | 1856688 |
| in vitro mutagenesis of biologically active transcripts of beet necrotic yellow vein virus rna 2: evidence that a domain of the 75-kda readthrough protein is important for efficient virus assembly. | rna 2 of the multipartite genome of beet necrotic yellow vein virus carries the cistron for 21-kda viral coat protein at its 5' extremity. the amber termination codon of the coat protein cistron undergoes suppression approximately 10% of the time so that translation continues into an adjacent 54-kda open reading frame, yielding a 75-kda readthrough protein. the roles of coat protein and the readthrough protein in infection were investigated with biologically active transcripts of rna 2. much of ... | 1992 | 1631051 |
| beet necrotic yellow vein virus accumulates inside resting spores and zoosporangia of its vector polymyxa betae bnyvv infects p. betae. | plasmodiophorids and chytrids are zoosporic parasites of algae and land plant and are distributed worldwide. there are 35 species belonging to the order plasmodiophorales and three species, polymyxa betae, p. graminis, and spongospora subterranea, are plant viral vectors. plasmodiophorid transmitted viruses are positive strand rna viruses belonging to five genera. beet necrotic yellow vein virus (bnyvv) and its vector, p. betae, are the causal agents for rhizomania. | 2007 | 17411435 |
| rna4-encoded p31 of beet necrotic yellow vein virus is involved in efficient vector transmission, symptom severity and silencing suppression in roots. | rna3 and rna4 of beet necrotic yellow vein virus (bnyvv) are not essential for virus multiplication, but are associated with vector-mediated infection and disease development in sugar beet roots. here, a unique role for rna4 in virus transmission, virulence and rna silencing suppression was demonstrated. mutagenic analysis revealed that the rna4-encoded p31 open reading frame (orf) was involved in efficient vector transmission and slight enhancement of symptom expression in some beta species. no ... | 2007 | 17412994 |
| efficient cell-to-cell movement of beet necrotic yellow vein virus requires 3' proximal genes located on rna 2. | rna 2 of beet necrotic yellow vein virus (bnyvv) carries six open reading frames. the four 3' proximal frames encode the proteins p42, p13, p15, and p14. the first three species present homologies to proteins encoded by three overlapping open reading frames (the triple gene block) in potexviruses, carlaviruses, and barley stripe mosaic virus. p14 does not display homology with other known plant viral proteins. the functions of p42, p13, p15, and p14 were investigated by site-directed mutagenesis ... | 1992 | 1604825 |
| a century of plant virus management in the salinas valley of california, 'east of eden'. | the mild climate of the salinas valley, ca lends itself well to a diverse agricultural industry. however, the diversity of weeds, crops and insect and fungal vectors also provide favorable conditions for plant virus disease development. this paper considers the incidence and management of several plant viruses that have caused serious epidemics and been significant in the agricultural development of the salinas valley during the 20th century. beet curly top virus (bctv) almost destroyed the newl ... | 2000 | 11137170 |
| identification of amino acids of the beet necrotic yellow vein virus p25 protein required for induction of the resistance response in leaves of beta vulgaris plants. | the rna3-encoded p25 protein of beet necrotic yellow vein virus (bnyvv) is responsible for the production of rhizomania symptoms of sugar beet roots (beta vulgaris subsp. vulgaris). here, it was found that the presence of the p25 protein is also associated with the resistance response in rub-inoculated leaves of sugar beet and wild beet (beta vulgaris subsp. maritima) plants. the resistance phenotype displayed a range of symptoms from no visible lesions to necrotic or greyish lesions at the inoc ... | 2008 | 18420811 |
| monitoring gene flow from transgenic sugar beet using cytoplasmic male-sterile bait plants. | one of the most discussed environmental effects associated with the use of transgenic plants is the flow of genes to plants in the environment. the flow of genes may occur through pollen since it is the reproductive system that is designed for gene movement. pollen-mediated gene escape is hard to control in mating plants. pollen from a wind pollinator can move over distances of more than 1000 m. to investigate the efficiency of transgenic pollen movement under realistic environmental conditions, ... | 2000 | 11123616 |
| 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 |
| molecular analyses of european a, b and p type sources of beet necrotic yellow vein virus and detection of the rare p type in kazakhstan. | nucleotide sequence analyses revealed that the genomes of the various european types of beet necrotic yellow vein virus (bnyvv), i.e. the a, b and p types, are strongly conserved. almost identical sequences were found, for instance, for a types originating from the netherlands, italy and former yugoslavia; these sequences were also almost identical to those determined c. 15 years ago by bouzoubaa et al. (1985; 1986 and 1987). this sequence stability of bnyvv types is in contrast to a pronounced ... | 2000 | 11003469 |
| structure and variability of the 3' end of rna 3 of beet soil-borne pomovirus--a virus with uncertain pathogenic effects. | pcr products representing c. 550 3' terminal bases of beet soil-borne pomovirus (bsbv) rna 3 were compared for sources of this virus from all major sugarbeet-growing areas in germany. in none of these areas conspicious symptoms could be attributed to the presence of bsbv. single strand conformation polymorphism analyses suggested that the bsbv genome may be very variable. this was confirmed by nucleotide sequence analysis. each pcr product which was analysed showed sequence differences to others ... | 2000 | 10948990 |
| p42 movement protein of beet necrotic yellow vein virus is targeted by the movement proteins p13 and p15 to punctate bodies associated with plasmodesmata. | cell-to-cell movement of beet necrotic yellow vein virus (bnyvv) is driven by a set of three movement proteins--p42, p13, and p15--organized into a triple gene block (tgb) on viral rna 2. the first tgb protein, p42, has been fused to the green fluorescent protein (gfp) and fusion proteins between p42 and gfp were expressed from a bnyvv rna 3-based replicon during virus infection. gfp-p42, in which the gfp was fused to the p42 n terminus, could drive viral cell-to-cell movement when the copy of t ... | 2000 | 10796018 |
| [expression of single-chain fv antibody for anti-beet necrotic yellow vein virus in escherichia coli]. | the heavy chains variable region gene (vh) of monoclonal antibody against beet necrotic yellow vein virus (bnyvv) was amplified from total dna extracted from anti-bnyvv hybridoma cells by pcr. sequencing showed that the vh belongs to mouse subgroup ii(a) and contains 360 bp, which code one hundred and twenty amino acids. the vh and vl genes were inserted into a plasmid which contains a linker sequence for constructing scfv gene. the new vector named ptc scfv. the scfv was produced in escherichia ... | 2000 | 11209682 |
| distribution of various types and p25 subtypes of beet necrotic yellow vein virus in germany and other european countries. | the distribution of various beet necrotic yellow vein virus (bnyvv) genotypes was studied using beet samples received from germany and neighbouring countries. almost exclusively b type bnyvv was detected in germany, whereas in neighbouring countries bnyvv a types with different compositions of the amino acid tetrad in positions 67-70 of the rna-3-encoded p25 are widely distributed. neither a types nor the p type have been able to become established in germany in the past decades, although there ... | 2008 | 18974924 |
| development of a highly sensitive nested rt-pcr method for beet necrotic yellow vein virus detection. | a diagnostic test incorporating reverse-transcription polymerase chain reaction (rt-pcr) and nested polymerase chain reaction (npcr) was developed for the detection of beet necrotic yellow vein virus (bnyvv). the rt-pcr used the primers designed by (henry et al., j. virol. methods 54 (1995)15) but refinements were made to the protocol including simplification of the extraction method, the use of standard reagents and adoption of a one-step procedure. none of these changes impaired sensitivity or ... | 2001 | 11377723 |
| the first 17 amino acids of the beet necrotic yellow vein virus rna-5-encoded p26 protein are sufficient to activate transcription in a yeast one-hybrid system. | the beet necrotic yellow vein virus (bnyvv) rna-5-encoded p26 protein is involved in the accentuation of symptoms expression of infected chenopodium quinoa plants and is capable of transcription activation (ta) in yeast. ta was previously localized within the first 55 residues of the p26 protein. interestingly, ta did not occur when c-terminally deleted forms of p26 were used. we used a genetic screen in the yeast one-hybrid system to select restored ta from randomly generated mutants. the ta do ... | 2009 | 19137435 |
| beet necrotic yellow vein virus particles localize to mitochondria during infection. | fluorescent beet necrotic yellow vein virus (bnyvv) particles were produced by replacing part of the readthrough domain of the minor coat protein p75 with the green fluorescent protein (gfp). the recombinant virus was functional in plants and p75-gfp was incorporated at one end of the rod-shaped virions. laser scanning confocal microscopy and transmission electron microscopy showed that virus-like particles, almost certainly authentic bnyvv virions, localized to the cytoplasmic surface of mitoch ... | 2001 | 11485394 |
| progress towards the understanding and control of sugar beet rhizomania disease. | rhizomania is a soil-borne disease that occurs throughout the major sugar beet growing regions of the world, causing severe yield losses in the absence of effective control measures. it is caused by beet necrotic yellow vein virus (bnyvv), which is transmitted by the obligate root-infecting parasite polymyxa betae. bnyvv has a multipartite rna genome with all natural isolates containing four rna species, although some isolates have a fifth rna. the larger rna1 and rna2 contain the housekeeping g ... | 2009 | 19161359 |
| a single u/c nucleotide substitution changing alanine to valine in the beet necrotic yellow vein virus p25 protein promotes increased virus accumulation in roots of mechanically inoculated, partially resistant sugar beet seedlings. | beet necrotic yellow vein virus (bnyvv) a type isolates e12 and s8, originating from areas where resistance-breaking had or had not been observed, respectively, served as starting material for studying the influence of sequence variations in bnyvv rna 3 on virus accumulation in partially resistant sugar beet varieties. sub-isolates containing only rnas 1 and 2 were obtained by serial local lesion passages; biologically active cdna clones were prepared for rnas 3 which differed in their coding se ... | 2009 | 19218223 |
| plant virus transmission by plasmodiophorid fungi is associated with distinctive transmembrane regions of virus-encoded proteins. | computer analysis of published sequence data has consistently identified two complementary transmembrane domains in the coat protein readthrough domains of benyviruses, furoviruses and pomoviruses and in the p2 proteins of bymoviruses. these viruses differ in genome organisation but are all transmitted by plasmodiophorid fungi. the second domain is absent or disrupted in naturally-occurring deletion mutants that cannot be fungally-transmitted. in a non-transmissible substitution mutant of beet n ... | 2001 | 11504421 |
| rapid screening for dominant negative mutations in the beet necrotic yellow vein virus triple gene block proteins p13 and p15 using a viral replicon. | point mutations were introduced into the genes encoding the triple gene bock movement proteins p13 and p15 of beet necrotic yellow vein virus (bnyvv). mutations which disabled viral cell-to-cell movement in chenopodium quinoa were then tested for their ability to act as dominant negative inhibiters of movement of wild-type bnyvv when expressed from a co-inoculated bnyvv rna 3-based replicon. for p13, three types of mutation inhibited the movement function: non-synomynous mutations in the n- and ... | 2001 | 11592709 |
| rapid screening of rna silencing suppressors by using a recombinant virus derived from beet necrotic yellow vein virus. | to counteract plant defence mechanisms, plant viruses have evolved to encode rna silencing suppressor (rss) proteins. these proteins can be identified by a range of silencing suppressor assays. here, we describe a simple method using beet necrotic yellow vein virus (bnyvv) that allows a rapid screening of rss activity. the viral inoculum consisted of bnyvv rna1, which encodes proteins involved in viral replication, and two bnyvv-derived replicons: rep3-p30, which expresses the movement protein p ... | 2009 | 19570958 |
| identification of beet necrotic yellow vein virus p25 pathogenicity factor-interacting sugar beet proteins that represent putative virus targets or components of plant resistance. | beet necrotic yellow vein virus (bnyvv) induces the most important disease threatening sugar beet. the growth of partially resistant hybrids carrying monogenic dominant resistance genes stabilize yield but are unable to entirely prevent virus infection and replication. p25 is responsible for symptom development and previous studies have shown that recently occurring resistance-breaking isolates possess increased p25 variability. to better understand the viral pathogenicity factor's interplay wit ... | 2009 | 19589075 |
| isolation of bnyvv coat protein-specific single chain fv from a mouse phage library antibody. | beet necrotic yellow vein virus (bnyvv) infects sugar beet plants worldwide and is responsible for the rhizomania disease and severe economic losses. disease severity and lack of naturally occurring resistant plants make it very difficult to control the virus, both from epidemiological and economic standpoints. therefore, early detection is vital to impose hygiene restrictions and prevent further spread of the virus in the field. immunoassays are one of the most popular methodologies for the pri ... | 2009 | 19857111 |
| p0 proteins of european beet-infecting poleroviruses display variable rna silencing suppression activity. | post-transcriptional gene silencing (ptgs), or rna silencing, is one of the key mechanisms of antiviral defence used by plants. to counter this defence response, viruses produce suppressor proteins that are able to inhibit the ptgs pathway or to interfere with some of its function. the aim of this study was to evaluate the rna silencing suppressor (rss) activity of p0 proteins from selected european isolates of the beet-infecting poleroviruses beet chlorosis virus (bchv) and beet mild yellowing ... | 2010 | 19955562 |
| effect of subsoiling on the yield of sugar beet under conditions of rhizomania infection. | the rhizomania is known in hungary since 1982. the causal agent, beet necrotic yellow vein benyvirus (bnyvv) is transmitted by a soil-borne fungus polymyxa betae keskin. a field experiment was done under rhizomania infested and non-infested conditions to compare the yield parameters of five tolerant and four sensitive sugar beet hybrids. tolerant varieties produced higher root yield under rhizomania infected conditions. the root yields of the sensitive varieties were similar to the tolerant ones ... | 2002 | 12701439 |
| characterization and diagnostic potential of foreign epitope-presenting ty1 virus-like particles expressed in escherichia coli and pichia pastoris. | we expressed a truncated p1 protein (p1-379) from the saccharomyces cerevisiae retrotransposon ty1 in the cytosol of escherichia coli and pichia pastoris, achieving maximum expression levels of 20 and 65 mg/l, respectively. two well-characterized epitopes from beet necrotic yellow vein virus (bnyvv) were used to evaluate the virus-like particles (vlps) as a presentation system for synthetic antigens. the epitopes were placed near the externally located n-terminus and at the internally located c- ... | 2010 | 20068357 |