| simple and rapid preparation of infected plant tissue extracts for pcr amplification of virus, viroid, and mlo nucleic acids. | a rapid, simple method for preparing plant tissues infected with viruses, viroids, or mlos using a commercial product known as gene releaser is described. the gene releaser polymeric matrix method produced plant extracts suitable for pcr amplification without the use of organic solvents, ethanol precipitation, or additional nucleic acid purification techniques. modification of maceration methods and/or extraction buffers resulted in the pcr amplification of potato spindle tuber, apple scar skin, ... | 1994 | 7868647 |
| nucleotide sequence of the 3' terminal region of the rna of two filamentous grapevine viruses. | the 3' terminal region of grapevine virus a (gva) and grapevine virus b (gvb), encompassing 1883 and 2136 nucleotides, respectively, was sequenced by the deoxynucleotide chain termination method. three putative open reading frames (orf) were identified in both genomic viral rnas, denoted 1 to 3 in the 5' to 3' direction. orf 1 encoded a polypeptide with estimated m(r) of 31 kda (gva) and 36.5 kda (gvb), possessing the g/d motif of the "30 k superfamily" movement proteins, and showing good alignm ... | 1994 | 7944948 |
| sensitive detection of grapevine virus a, b, or leafroll-associated iii from viruliferous mealybugs and infected tissue by cdna amplification. | dna primers specific for grapevine virus a (gva), grapevine virus b (gvb) or grapevine leafroll-associated virus iii (glrav-iii) were constructed based on the nucleotide sequence of a segment of each viral genome. dna primers were utilized for cdna synthesis and polymerase chain reaction (pcr) amplification of a 430 bp fragment from extracts of gva-infected grapevine tissue or viruliferous mealybugs and 450 bp and 340 bp dna fragments from extracts of gvb and glrav-iii-infected grapevine tissues ... | 1994 | 8051225 |
| properties of a filamentous virus isolated from grapevines affected by corky bark. | a virus with highly flexuous filamentous particles c. 800 nm long, showing distinct transverse striations was isolated with high frequency (60%) by inoculation of nicotiana occidentalis with sap from grapevine accessions indexing positive for corky bark. the virus, for which the name grapevine virus b (gvb) is proposed, has an ssrna genome with mol. wt. of c. 2.5 x 10(6) da (c. 7600 nt) and coat protein subunits with mol. wt. of c 23,000 da. gvb has a very restricted herbaceous host range and wa ... | 1993 | 8503778 |
| the nucleotide sequence and genomic organization of grapevine virus b. | grapevine virus b (gvb) is a tentative member of the genus trichovirus. the 5'-terminal region of the rna genome of gvb comprises 5437 nucleotides and has been sequenced by the dideoxynucleotide chain termination method. evidence was obtained that the rna is capped. two putative open reading frames (orfs) were identified. orf 1 coded for a 194.7 kda polypeptide with conserved motifs of replication-related proteins of positive-strand rna viruses (i.e. methyltransferase, helicase and rna-dependent ... | 1996 | 8887502 |
| grapevine virus a: nucleotide sequence, genome organization, and relationship in the trichovirus genus. | the 5' terminal region of the genomic rna of grapevine virus a (gva), a tentative member of the trichovirus genus, encompassing 5466 nucleotides, was sequenced. evidence was obtained that the rna is capped. two putative open reading frames (orf) were identified: orf 1 that codes for a 194 kda polypeptide with conserved motifs of replication-related proteins of positive-strand rna viruses, and orf 2 that encodes a 19 kda polypeptide with no significant homology with protein sequences from databas ... | 1997 | 9125055 |
| a spot-pcr technique for the detection of phloem-limited grapevine viruses. | specific amplification of genomic fragments of grapevine trichovirus a (gva), grapevine trichovirus b (gvb) and grapevine leafroll-associated closterovirus 3 (glrav3) was obtained by reverse transcription-pcr on total nucleic acid solubilized from small pieces of charged nylon membrane, on which a drop of crude infected grapevine sap was spotted (spot-pcr). a thermal treatment (95 degrees for 10 degrees) of spotted sap in a buffered solution improved the release of viral template. consistent amp ... | 1997 | 9220395 |
| grapevine berry inner necrosis, a new trichovirus: comparative studies with several known trichoviruses. | biological, morphological and serological properties of grapevine berry inner necrosis virus (ginv), the casual virus of grapevine berry inner necrosis disease occurring in japan, were compared with those of several known trichoviruses. host range and particle length of ginv were quite similar to those of apple chlorotic leaf spot trichovirus (aclsv). in ultrathin sections of the infected tissues, ginv particles existed in aggregated masses in the cytoplasm of vascular parenchyma and mesophyll c ... | 1997 | 9267448 |
| infectious cdna clones of two grapevine viruses. | full-length cdna copies of the genomes of grapevine virus a (gva) and grapevine virus b (gvb) under the control of bacteriophage t7 promoter have been synthesized, which were refractory to cloning in escherichia coli. however, both transcribed cdnas were infectious when mechanically inoculated to nicotiana plants. a full-length cdna copy of gvb was engineered in pcass2, a plasmid containing a partially duplicated copy of the ca35s promoter, but was rather unstable in escherichia coli. no infecti ... | 2000 | 10752561 |
| nucleotide sequence and genome organisation of cherry mottle leaf virus and its relationship to members of the trichovirus genus. | the nucleotide sequence of cherry mottle leaf virus (cmlv) was determined and compared to sequences of a number of plant viruses including the type member of the trichovirus genus (apple chlorotic leafspot virus, aclsv), and members of the vitivirus genus including grapevine virus b, (gvb). the cmlv genome was determined to consist of 8003 nt excluding the poly(a) tail at the 3' end of the genome. the overall a + u content of cmlv genomic rna was 59.1%, which is similar to aclsv, but significant ... | 2000 | 10881685 |
| immunodetection and subcellular localization of the proteins encoded by orf 3 of grapevine viruses a and b. | polyclonal antisera were raised to escherichia coli-expressed orf3 products (putative movement proteins) of grapevine virus a (gva) and grapevine virus b (gvb) (genus vitivirus), and used for their immunodetection in infected plants. western blot analysis of subfractionated cellular compartments showed that the distribution of both proteins was comparable to that of plant virus movement proteins, as they were transiently present in a crude membrane fraction and accumulated in a cell wall-enriche ... | 2000 | 11003467 |
| improved rna extraction and one-tube rt-pcr assay for simultaneous detection of control plant rna plus several viruses in plant extracts. | a procedure was developed for simultaneous detection of plant rna viruses and of plant rna, as a control. rt-pcr amplification with primers designed for the detection of the plant mrnas encoding malate dehydrogenase (mdh) and the large subunit of ribulose bisphosphate carboxylase oxygenase (rubiscol) was used for the development of a plant extraction procedure that consistently yields extracts that can be amplified. the control amplification was used successfully on extracts from cane, leaf and/ ... | 2000 | 11011079 |
| extensive variation of sequence within isolates of grapevine virus b+. | four regions covering 1247 nucleotides of the rna genome of 20 isolates of a vitivirus, grapevine virus b (gvb), from three countries were analyzed. all the regions in these isolates varied in sequence as compared to the published gvb sequence. of these, the intergenic region varied the most, with 73.2% nucleotide sequence homology, while orf4 encoding coat protein varied the least when compared both at nucleotide sequence (80.3% homology) and at amino acid sequence levels (90.6% homology). the ... | 2004 | 15284488 |
| isolation of recombinant antibodies (scfvs) to grapevine virus b. | a panel of 15 recombinant single chain antibodies (scfv) specific to grapevine virus b (gvb) were recovered from a human combinatorial scfv antibody library using the phage display technique against purified virus particles. two selected scfv-encoding genes were expressed in recombinant escherichia coli cells as dimeric antibodies. successful detection of gvb in tissues of herbaceous hosts and grapevine was obtained in a direct binding assay using dimeric scfvs. this reagent was also shown to su ... | 2004 | 15664068 |
| identification, detection and transmission of a new vitivirus from mentha. | mentha x gracilis 'variegata' is an ornamental clone with a phenotype caused by virus infection. several clones were ordered from mail-order nurseries in an attempt to identify a virus consistently associated with symptoms. one of these clones did not exhibit typical 'variegata' symptoms, and steps were taken to identify any agents causing the 'off-type' symptoms. one of the viruses identified in the atypical 'variegata' clone is a previously unknown virus, a member of the family flexiviridae. s ... | 2007 | 17680328 |
| sequencing and assembly of a full-length infectious clone of grapevine virus b and its infectivity on herbaceous plants. | grapevine virus b (gvb) has been found associated with corky bark-diseased vines. although the sequence of a 7.6-kb cdna clone from a gvb isolate from italy has been described, striking differences in sequences between gvb isolates prompted us to construct an additional full-length gvb clone from the isolate 94/971 and to determine its complete sequence. the cdna of gvb 94/971 shared a nucleotide sequence identity of only 77% with the gvb isolate from italy. the cdna of gvb 94/971 was infectious ... | 2008 | 17943392 |
| real-time rt-pcr (taqman) assays for the detection of viruses associated with rugose wood complex of grapevine. | real-time taqman rt-pcr (taqman rt-pcr) assays were developed to detect the viruses associated with rugose wood complex of grapevines. the viruses detected were rupestris stem pitting-associated virus in the genus foveavirus, grapevine virus a, grapevine virus b and grapevine virus d in the genus vitivirus. the coat protein was found to be the most conserved gene within the viral species, therefore, the primers and probes for taqman rt-pcr assays were designed from the multiple alignment of the ... | 2008 | 18848580 |
| simultaneous detection of nine grapevine viruses by multiplex reverse transcription-polymerase chain reaction with coamplification of a plant rna as internal control. | abstract a multiplex reverse transcription-polymerase chain reaction (mrt-pcr) was developed for simultaneous detection of nine grapevine viruses: arabis mosaic virus, grapevine fanleaf virus, grapevine virus a, grapevine virus b, rupestris stem pitting-associated virus, grapevine fleck virus, grapevine leafroll-associated virus-1, -2, and -3, in combination with a plant rna internal control used as an indicator of the effectiveness of rna extraction and rt-pcr. primers were designed from conser ... | 2006 | 18943959 |
| cloning and characterization of vigg, a novel virus-induced grapevine protein, correlated with fruit quality. | we report here the identification and characterization of vigg, a novel virus-induced grapevine protein. analysis of vigg expression in grapevine demonstrated that vigg was constitutively expressed in leaves and stems in virus-infected grapevine, and that vigg expression was induced by grapevine virus a (gva) infection, but not by infection with other viruses. the virus-induced expression profile of vigg was supported by the finding that virus-free meristem cultures prepared from virus-infected ... | 2009 | 19138527 |
| a diagnostic oligonucleotide microarray for simultaneous detection of grapevine viruses. | at least 58 viruses have been reported to infect grapevines causing economic damage globally. conventional detection strategies based on serological assays, biological indexing and rt-pcr targeting one or few viruses in each assay are widely used. grapevines are prone to contain mixed infections of several viruses, making the use of these techniques time-consuming. a 70-mer oligonucleotide microarray able to detect simultaneously a broad spectrum of known viruses as well as new viruses by cross- ... | 2010 | 19914293 |
| analysis of multiple virus-infected grapevine plant reveals persistence but uneven virus distribution. | ln33 grapevine plants were artificially inoculated with budwoods originating from a field-cultivated traminer grapevine which was naturally infected with grapevine leafroll-associated virus 1 (glrav-1), grapevine virus a (gva), grapevine virus b (gvb), rupestris stem pitting-associated virus (rspav), and an unclassified tymovirus. four years after inoculation, a comparison of the cane weights between healthy and infected grapevines did not show any significant difference. corky bark symptoms or ... | 2009 | 19941393 |
| rugose wood-associated viruses do not appear to be involved in shiraz (syrah) decline in south africa. | the presence of rugose-wood-associated viruses of the genera foveavirus and vitivirus in the family betaflexiviridae was investigated in various clones of own-rooted and grafted vitis vinifera cv. shiraz that were affected, or not, by shiraz decline, and in rootstocks. rt nested-pcr amplification of double-stranded rna using degenerate primers for the simultaneous detection of foveaviruses and vitiviruses (dovas ci, katis ni in j virol meth 170:99-106, 2003), cloning of dna amplicons, sscp analy ... | 2010 | 20549265 |
| divergent molecular variants of grapevine virus b (gvb) from corky bark (cb)-affected and cb-negative ln33 hybrid grapevines. | analysis of two grapevine virus b (gvb)-infected ln33 hybrid grapevines revealed that a plant exhibiting clear symptoms of corky bark (cb) disease was infected with two molecular variants of the virus, whereas a plant exhibiting no disease symptoms was infected with only one variant. sequence results indicated that the single variant in the cb-negative grapevine was also one of the two present in the cb-affected hybrid. plant extracts from these two grapevines were used to successfully transmit ... | 2010 | 20628801 |
| the orf3-encoded proteins of vitiviruses gva and gvb induce tubule-like and punctate structures during virus infection and localize to the plasmodesmata. | the genomic rna of vitiviruses contains 5 open reading frames (orf). orf3 encodes a protein to which the function of a movement protein (mp) was assigned, based on sequence homology with other viral proteins. the aim of the research described in this paper was to gain further insight in distribution profile of the orf3 product encoded by the vitiviruses grapevine virus a (gva) and grapevine virus b (gvb). expression of the gva mp-gfp fusion protein via the virus genome in nicotiana benthamiana l ... | 2011 | 22051060 |
| comparative detection of a large population of grapevine viruses by taqman(®) rt-qpcr and elisa. | grapevine (vitis spp.) can be infected by numerous viruses that are often widespread and of great economic importance. reliable detection methods are necessary for sanitary selection which is the only way to partly control grapevine virus diseases. biological indexing and elisa are currently the standard methods for screening propagation material, and pcr-methods are becoming increasingly popular. due to the diversity of virus isolates, it is essential to verify that the tests allow the detectio ... | 2017 | 27923589 |
| multiplex rt-pcr method for the simultaneous detection of nine grapevine viruses. | viral diseases are a serious pathological problem for grapevines, and in recent years the need for increasingly specific and rapid diagnostic methods for the selection of propagation materials has grown. arabis mosaic virus, grapevine fanleaf virus, grapevine virus a, grapevine virus b, grapevine rupestris stem pitting-associated virus, grapevine fleck virus, and grapevine leafroll-associated viruses 1, 2, and 3 are nine of the most widespread viruses that naturally infect grapevines. a multiple ... | 2015 | 25287494 |
| evidence of grapevine leafroll associated virus-1-3, grapevine fleck virus and grapevine virus b occurring in himachal pradesh, india. | during a survey conducted in the grapevine orchards of himachal pradesh, variety of symptoms ranging from leaf yellowing, vein greening, reduced leaf size, downward rolling/cup shaped leaves to reduced fruit bearing were observed. symptomatic leaf samples were collected and analyzed by serological (das-elisa) and molecular methods (rt-pcr, pcr) for viruses and phytoplasma known worldwide on grapevine. das-elisa was used for detection of grapevine leafroll associated virus 1, 2 and 3 (glrav-1, 2 ... | 2013 | 24426260 |
| transmission of six ampeloviruses and two vitiviruses to grapevine by phenacoccus aceris. | grapevine leafroll disease is caused by grapevine leafroll-associated viruses (glravs). these viruses are common in vineyards worldwide and often associated with vitiviruses that are involved in the rugose wood complex of grapevine. ten mealybug species are known as vectors of one or several of these grapevine viruses, including the apple mealybug phenacoccus aceris which is widespread in holarctic regions and able to transmit grapevine leafroll-associated virus-1 and -3 (glrav-1 and -3). our ai ... | 2012 | 22439861 |
| brief report of the construction of infectious dna clones of south african genetic variants of grapevine virus a and grapevine virus b. | recent research results strongly suggest that certain genetic variants of grapevine virus a (gva) and grapevine virus b (gvb), two members of the vitivirus genus of the family betaflexiviridae, are the cause of shiraz disease and corky bark disease of grapevines in south africa, respectively. to investigate this hypothesis, work was undertaken to construct dna clones of these viruses. | 2015 | 26640751 |
| detection and characterisation of two novel vitiviruses infecting actinidia. | two co-infecting novel vitiviruses from actinidia chinensis were identified from mechanically inoculated nicotiana occidentalis. both virus genomes were sequenced and share 64% nucleotide identity. their overall structure is typical of vitiviruses, with five open reading frames (orfs) and a polyadenylated 3' end. open reading frame 4 (orf4) encodes the coat protein, the most conserved gene of the vitiviruses, in which they share 75% amino acid identity, 61-68% with grapevine virus b, 55-59% with ... | 2012 | 22274622 |
| a novel vitivirus-like sequence found in arracacia xanthorrhiza plants by high throughput sequencing. | high throughput sequencing (hts) is a very powerful tool for detecting and discovering novel viral-like sequences without prior knowledge of the sequence. here we describe the complete genome of a new vitivirus-like sequence that was found in arracacha (arracacia xanthorrhiza) plants using hts technology. the complete genome sequence was validated by sanger sequencing. the genomic organization of the new putative vitivirus resembles that of grapevine virus b (gvb) and grapevine virus d (gvd). th ... | 2017 | 28316018 |
| first molecular characterization of grapevine virus b (gvb) in portuguese grapevine cultivars and improvement of the rt-pcr detection assay. | this work describes the first molecular characterization of grapevine virus b (gvb) in portuguese grapevine cultivars. during a routine screening of 44 accessions in the national collection of grapevine varieties (can prt051), 17 were found infected with gvb in das-elisa assays with commercial antibodies. however, only six of the corresponding isolates were successfully amplified using primer pairs described in the literature. the sequence variants (orf4-3'utr, 1147 nt) retrieved from these isol ... | 2016 | 27604120 |
| detection and sequence analysis of grapevine virus b isolates from china. | the presence of grapevine virus b (gvb) was detected in 188 grapevine samples from china by double antibody sandwich elisa (das-elisa) and reverse transcription-pcr (rt-pcr). the accuracy of detection by rt-pcr was confirmed by sequencing amplified pcr fragments. seventeen samples were gvb-positive by das-elisa and five by rt-pcr. the isolate qmw proved to be positive by rt-pcr only, and four isolates (dgwh, dgw, qm, and jfl) could be detected by both methods. among the five gvb-positive samples ... | 2014 | 24957724 |