Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
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| athsp70-15-deficient arabidopsis plants are characterized by reduced growth, a constitutive cytosolic protein response and enhanced resistance to tumv. | arabidopsis thaliana contains 18 genes encoding hsp70s. this heat shock protein superfamily is divided into two sub-families: dnak and hsp110/sse. in order to functionally characterize members of the hsp70 superfamily, loss-of-function mutants with reduced cytosolic hsp70 expression were studied. athsp70-1 and athsp70-2 are constitutively expressed and represent the major cytosolic hsp70 isoforms under ambient conditions. analysis of single and double mutants did not reveal any difference compar ... | 2011 | 21418353 |
| dynamics of a plant rna virus intracellular accumulation: stamping machine versus geometric replication. | the tremendous evolutionary potential of rna viruses allows them thriving despite host defense mechanisms and endows them with properties as emergence, host switching and virulence. the frequency of mutant viruses after an infectious process results from the interplay between the error rate of the viral replicase, from purifying mechanisms acting after transcription on aberrant rnas, and from the amplification dynamics of virus rna positive (+) and negative (-) strands. two extreme scenarios des ... | 2011 | 21515574 |
| structure of the autocatalytic cysteine protease domain of potyvirus helper-component proteinase. | the helper-component proteinase (hc-pro) of potyvirus is involved in polyprotein processing, aphid transmission and suppression of antiviral rna silencing. there is no high-resolution structure reported for any part of hc-pro, hindering mechanistic understanding of its multiple functions. we have determined the crystal structure of the cysteine protease domain of hc-pro from turnip mosaic virus at 2.0 å resolution. as a protease, hc-pro only cleaves a gly-gly dipeptide at its own c-terminus. the ... | 2011 | 21543324 |
| misregulation of auxin response factor 8 underlies the developmental abnormalities caused by three distinct viral silencing suppressors in arabidopsis. | in arabidopsis, micro (mi)rnas and trans-acting (ta-si)rnas synthesized directly or indirectly through the dicer-like-1 (dcl1) ribonuclease have roles in patterning and hormonal responses, while dcl2,3,4-dependent small-interfering (si)rnas are mainly involved in silencing of transposable elements and antiviral defense. viral suppressors of rna silencing (vsrs) produced by phytoviruses to counter plant defense may perturb plant developmental programs because of the collision of their inhibitory ... | 2011 | 21589905 |
| combinations of a host resistance gene and the ci gene of turnip mosaic virus differentially regulate symptom expression in brassica rapa cultivars. | in the pathosystem of brassica rapa and turnip mosaic virus (tumv), the type of symptoms expressed by susceptible plants are determined by the gene combinations between the host cultivar and virus strain. in this study, we found that the resistance reaction and symptoms such as systemic lethal necrosis, leaf malformation and mosaic were differentially determined, depending on the combinations of the genotypes for a host locus or two closely linked host loci and the viral ci gene. systemic necros ... | 2011 | 21625976 |
| tempo and mode of plant rna virus escape from rnai-mediated resistance. | a biotechnological application of artificial micrornas (amir) is the generation of plants resistant to virus infection. this resistance has proven to be highly effective and sequence-specific. however, before these transgenic plants can be deployed in the fields, it is important to evaluate the likelihood of emergence of resistance-breaking mutants. two issues are of particular interest: (i) whether such mutants can arise in non-transgenic plants that may act as reservoirs; and (ii) whether subo ... | 2011 | 21775453 |
| differences in the mechanism of inoculation between a semipersistent and a non-persistent aphid-transmitted plant virus. | inoculation of the semipersistent cauliflower mosaic virus (camv, genus caulimovirus) is associated to successive brief (5-10 s) intracellular stylet punctures (pd) when aphids probe in epidermal and mesophyll cells. in contrast to non-persistent viruses, there is no evidence of which of the pd sub-phases (ii-1, ii-2 and ii-3) is involved in the inoculation of camv. experiments were conducted using the electrical penetration graph (epg) technique to investigate what particular sub-phases of the ... | 2011 | 22090212 |
| Brief report: genome sequence and construction of an infectious cDNA clone of Ribgrass mosaic virus from Chinese cabbage in Korea. | Ribgrass mosaic virus (RMV) has severely decreased the production and lowered quality of Chinese cabbage co-infected with Turnip mosaic virus (63.4%) in Korea. The complete genome sequence of RMV isolated from Brassica rapa ssp. pekinensis was determined. The full genome consisted of 6,304 nucleotides and showed sequence identities of 91.5-94.2% with the corresponding genome of other RMV strains. Full-length cDNA of RMV-Br was amplified by RT-PCR with a 5'-end primer harboring a T7 promoter sequ ... | 2011 | 22143325 |
| light quantity and photosystem function mediate host susceptibility to turnip mosaic virus via a salicylic acid-independent mechanism. | evidence going as far back as the early part of the 20th century suggests that both light and chloroplast function may play key roles in host susceptibility to viruses. despite the long history of such work, confirmation of these phenomena and a determination of the underlying mechanisms remain elusive. here, we revisited these questions using modern imaging technologies to study the susceptibility of nicotiana benthamiana to turnip mosaic virus (tumv). we found that both light deficiency and ph ... | 2011 | 21091158 |
| identification and validation of reference genes for normalization of transcripts from virus-infected arabidopsis thaliana. | real-time quantitative polymerase chain reaction (qpcr) of complementary dna is now a standard method for studies of gene expression. however, qpcr can identify genuine variation only when transcript quantities are accurately normalized to an appropriate reference. to identify the most reliable reference genes for transcript quantification by qpcr, we describe a systematic evaluation of candidate reference genes of arabidopsis thaliana ecotype columbia-0 (col-0). twelve genes were selected for t ... | 2011 | 21091160 |
| tissue blot immunoassay and direct rt-pcr of cucumoviruses and potyviruses from the same nitropure nitrocellulose membrane. | a method is described for using nitropure nitrocellulose (npn) membranes as an effective solid matrix for retrieval of template rna of three potyviruses, tobacco etch virus, soybean mosaic virus and turnip mosaic virus, and two cucumoviruses, cucumber mosaic virus and peanut stunt virus. these npn membranes were also used for tissue blot immunosorbent assays (tbias) to identify and detect plant viruses. for rna detection, discs from dried membranes blotted with infected tissue were minimally cle ... | 2010 | 21126542 |
| the nuclear inclusion a (nia) protease of turnip mosaic virus (tumv) cleaves amyloid-β. | the nuclear inclusion a (nia) protease of turnip mosaic virus (tumv) is responsible for the processing of the viral polyprotein into functional proteins. nia was previously shown to possess a relatively strict substrate specificity with a preference for val-xaa-his-gln↓, with the scissile bond located after gln. the presence of the same consensus sequence, val(12)-his-his-gln(15), near the presumptive α-secretase cleavage site of the amyloid-β (aβ) peptide led us to hypothesize that nia could po ... | 2010 | 21187975 |
| nucleotide bias of dcl and ago in plant anti-virus gene silencing. | plant dicer-like (dcl) and argonaute (ago) are the key enzymes involved in anti-virus post-transcriptional gene silencing (av-ptgs). here we show that av-ptgs exhibited nucleotide preference by calculating a relative av-ptgs efficiency on processing viral rna substrates. in comparison with genome sequences of dicot-infecting turnip mosaic virus (tumv) and monocot-infecting cocksfoot streak virus (csv), viral-derived small interfering rnas (vsirnas) displayed positive correlations between av-ptgs ... | 2010 | 21203927 |
| turnip mosaic virus (tumv) is able to use alleles of both eif4e and eif(iso)4e from multiple loci of the diploid brassica rapa. | three copies of eif4e and three copies of eif(iso)4e have been identified and sequenced from a turnip mosaic virus (tumv)-susceptible, inbred, diploid brassica rapa line, r-o-18. one of the copies of eif4e lacked exons 2 and 3 and appeared to be a pseudogene. the two other copies of eif4e and two of the three copies of eif(iso)4e were isolated from a bacterial artificial chromosome library of r-o-18. using an arabidopsis line (col-0::dspm) with a transposon knock-out of the eif(iso)4e gene which ... | 2010 | 20672877 |
| a model for the biogenesis of turnip mosaic virus replication factories. | nicotiana benthamiana plants were agroinfiltrated with an infectious clone of the turnip mosaic virus (tumv) that was engineered to tag replication vesicles with either gfp or mcherry fluorescent proteins. punctuate vesicle structures were observed in the cytoplasm of infected cells corresponding to viral replication factories. the vesicles were highly motile and co-aligned with the microfilaments. utilization of latrunculin b, an inhibitor of microfilament polymerization, reduced accumulation o ... | 2010 | 20798828 |
| mapping the self-interacting domains of tumv hc-pro and the subcellular localization of the protein. | the helper component-proteinase (hc-pro) of potyviruses is a multifunctional protein involved in aphid transmission, polyprotein processing, cell-to-cell and long-distance movement, genome amplification and symptom expression. the hc-pros of several potyviruses interact with themselves but the key domains responsible for self-interaction are apparently not conserved. in our experiments, yeast two-hybrid assays and bimolecular fluorescence complementation showed that turnip mosaic virus (tumv) hc ... | 2010 | 20938729 |
| the second face of a known player: arabidopsis silencing suppressor atxrn4 acts organ-specifically. | plant viruses exploit the symplastic transport pathway provided by plasmodesmata by encoding for specialized movement proteins, which interact with host factors to enable viral intracellular and intercellular spread. stable expression of the potato leaf roll virus movement protein mp17 in arabidopsis results in a carbohydrate export block and stunted growth. to identify host factors essential for viral infection, we screened a progeny population of ems (ethyl methanesulfonate)-mutagenized arabid ... | 2010 | 21039560 |
| single amino acid changes in the turnip mosaic virus viral genome-linked protein (vpg) confer virulence towards arabidopsis thaliana mutants knocked out for eukaryotic initiation factors eif(iso)4e and eif(iso)4g. | previous resistance analyses of arabidopsis thaliana mutants knocked out for eukaryotic translation initiation factors showed that disruption of the at-eif(iso)4e or both the at-eif(iso)4g1 and at-eif(iso)4g2 genes resulted in resistance against turnip mosaic virus (tumv). this study selected tumv virulent variants that overcame this resistance and showed that two independent mutations in the region coding for the viral genome-linked protein (vpg) were sufficient to restore tumv virulence in at- ... | 2010 | 19741065 |
| evolutionary trajectory of turnip mosaic virus populations adapting to a new host. | little is known about how some plant viruses establish successful cross-species transmission whilst others do not; the genetic basis for adaptation is largely unknown. this study investigated the genetic changes that occurred using the progeny of an infectious clone, p35tunos, derived from the turnip mosaic virus (tumv) uk 1 isolate, which has a brassica host type, but rarely infects raphanus systemically and then only asymptomatically. the genetic trajectory leading to viral adaptation was stud ... | 2010 | 19906944 |
| the p3 protein of turnip mosaic virus can alone induce hypersensitive response-like cell death in arabidopsis thaliana carrying tuni. | strains tur1 and tuc of turnip mosaic virus (tumv) induce different symptoms on arabidopsis thaliana ecotype landsberg erecta (ler); plants infected with tur1 develop systemic necrosis, while tuc causes mosaics. we previously found that the ler systemic necrosis was controlled by a single dominant gene, tuni (tumv necrosis inducer), and that it was actually a form of host defense response leading to a hypersensitive reaction (hr)-like cell death. to identify the viral factor interacting with tun ... | 2010 | 20064058 |
| hc-pro, a potyvirus rna silencing suppressor, cancels cycling of cucumber mosaic virus in nicotiana benthamiana plants. | the mixed infection of cucumber mosaic virus (cmv) and a potyvirus has been known to increase cmv titer in nicotiana benthamiana plants, resulting in synergistic viral symptoms. we found that among three potyviruses--potato virus y (pvy), turnip mosaic virus (tumv), and clover yellow vein virus (c1yvv)--synergistic effects on cmv (or a recombinant cmv vector) titers were most efficiently induced by a co-infection with pvy in n. benthamiana plants. in addition, the helper component-proteinase (hc ... | 2010 | 20162445 |
| identification of plant viruses using one-dimensional gel electrophoresis and peptide mass fingerprints. | a generic assay to detect and partially characterize unknown viruses from plants was developed. proteins extracted from virus-infected and uninfected plants were separated in one dimension by sds polyacrylamide gel electrophoresis. differentially expressed protein bands were eluted after trypsin digestion and resulting peptide fragments separated according to their mass by matrix-assisted laser-desorption ionization time-of-flight (maldi-tof) mass spectrometry. resulting peptide mass fingerprint ... | 2010 | 20170682 |
| mutational analysis of the putative pipo of soybean mosaic virus suggests disruption of pipo protein impedes movement. | the presence of a small open reading frame embedded in the p3 cistron of potyvirus turnip mosaic virus, termed "pipo," was recently discovered. we have now studied the putative pipo of soybean mosaic virus (smv). introduction of single, or multiple, stop codon mutations at different locations within pipo, without substitution in polyprotein amino acids, did not abolish replication, but restricted the virus to small cluster of cells within the inoculated leaves. furthermore, extensive mutagenesis ... | 2010 | 20170935 |
| arabidopsis rna-dependent rna polymerases and dicer-like proteins in antiviral defense and small interfering rna biogenesis during turnip mosaic virus infection. | plants respond to virus infections by activation of rna-based silencing, which limits infection at both the single-cell and system levels. viruses encode rna silencing suppressor proteins that interfere with this response. wild-type arabidopsis thaliana is immune to silencing suppressor (hc-pro)-deficient turnip mosaic virus, but immunity was lost in the absence of dicer-like proteins dcl4 and dcl2. systematic analysis of susceptibility and small rna formation in arabidopsis mutants lacking comb ... | 2010 | 20190077 |
| turnip mosaic virus genome-linked protein vpg binds c-terminal region of cap-bound initiation factor 4e orthologue without exhibiting host cellular specificity. | to investigate the binding specificity of turnip mosaic virus (tumv) viral protein-genome linked (vpg) with translation initiation factor 4e, we evaluated here the kinetic parameters for the interactions of human eif4e, caenorhabditis elegans ife-3 and ife-5 and arabidopsis eifiso4e, by surface plasmon resonance (spr). the results indicated that tumv vpg does not show a binding preference for arabidopsis eifiso4e, even though it is from a host species whereas the other eif4e orthologues are not. ... | 2009 | 19122207 |
| complete genomic sequence analyses of turnip mosaic virus basal-br isolates from china. | isolates of turnip mosaic virus (tumv) are divided into four molecular lineages based on host range and geographical origins. basal-br is one of the four lineages and represented a new emergent lineage in east asia. in one previous paper, we report the occurrence of basal-br isolates in china. here, we presented the first two complete genomic sequences of chinese tumv basal-br isolates, wflb06 and tanx2. the genomes of both isolates were 9833 nucleotides excluding the poly(a) tail, and had ident ... | 2009 | 19238532 |
| molecular evolution of a viral non-coding sequence under the selective pressure of amirna-mediated silencing. | plant micrornas (mirna) guide cleavage of target mrnas by dicer-like proteins, thereby reducing mrna abundance. native precursor mirnas can be redesigned to target rnas of interest, and one application of such artificial microrna (amirna) technology is to generate plants resistant to pathogenic viruses. transgenic arabidopsis plants expressing amirnas designed to target the genome of two unrelated viruses were resistant, in a highly specific manner, to the appropriate virus. here, we pursued two ... | 2009 | 19247440 |
| synergistic interaction between the potyvirus, turnip mosaic virus and the crinivirus, lettuce infectious yellows virus in plants and protoplasts. | lettuce infectious yellows virus (liyv), the type member of the genus crinivirus in the family closteroviridae, is specifically transmitted by the sweet potato whitefly (bemisia tabaci) in a semipersistent manner. liyv infections result in a low virus titer in plants and protoplasts, impeding reverse genetic efforts to analyze liyv gene/protein functions. we found that synergistic interactions occurred in mixed infections of liyv and turnip mosaic virus (tumv) in nicotiana benthamiana plants, an ... | 2009 | 19409943 |
| differential requirement of ribosomal protein s6 by plant rna viruses with different translation initiation strategies. | potyvirus infection has been reported to cause an increase in the mrna transcripts of many plant ribosomal proteins (r-proteins). in this study, increased expression of r-protein mrna transcripts was determined to occur in nicotiana benthamiana during infection by potyviruses as well as a tobamovirus demonstrating that this response is not unique to potyviruses. five r-protein genes, rps6, rpl19, rpl13, rpl7, and rps2, were silenced in n. benthamiana to test their roles in viral infection. the a ... | 2009 | 19524993 |
| application of game theory to the interaction between plant viruses during mixed infections. | natural mixed infections of plant viruses are frequent, often leading to unpredictable variations in symptoms, infectivity, accumulation and/or vector transmissibility. cauliflower mosaic caulimovirus (camv) has often been found in mixed infections with turnip mosaic potyvirus (tumv) in plants of the genus brassica. this study addressed the effect of mixed infection on infectivity, pathogenicity and accumulation of camv and tumv in arabidopsis thaliana plants inoculated mechanically with cdna in ... | 2009 | 19587130 |
| turnip mosaic virus rna replication complex vesicles are mobile, align with microfilaments, and are each derived from a single viral genome. | nicotiana benthamiana plants were agroinoculated with an infectious cdna clone of turnip mosaic virus (tumv) that was engineered to express a fluorescent protein (green fluorescent protein [gfp] or mcherry) fused to the viral 6k2 protein known to induce vesicle formation. cytoplasmic fluorescent discrete protein structures were observed in infected cells, corresponding to the vesicles containing the viral rna replication complex. the vesicles were motile and aligned with microfilaments. intracel ... | 2009 | 19656892 |
| veinal necrosis induced by turnip mosaic virus infection in arabidopsis is a form of defense response accompanying hr-like cell death. | in the pathosystems of turnip mosaic virus (tumv) with brassicaceae crops, various symptoms, including mosaic and necrosis, are observed. we previously reported a necrosis-inducing factor tuni in arabidopsis thaliana, a model species. in this study, we show that the necrotic symptom induced by tuni, observed along the veins, was actually a form of defense response accompanying a hypersensitive reaction (hr)-like cell death in the veinal area. the virus is often localized in the necrotic region. ... | 2008 | 18184069 |
| recognition of the hyaloperonospora parasitica effector atr13 triggers resistance against oomycete, bacterial, and viral pathogens. | phytopathogenic oomycetes cause some of the most devastating diseases affecting agricultural crops. hyaloperonospora parasitica is a native oomycete pathogen of arabidopsis and is related to other oomycete phytopathogens that include several species of phytophthora, including the causal agent of potato late blight. recently, four oomycete effector genes have been isolated, and several oomycete genomes have been sequenced. we have developed an efficient and genetically amenable system to test put ... | 2008 | 18198274 |
| heat shock 70 protein interaction with turnip mosaic virus rna-dependent rna polymerase within virus-induced membrane vesicles. | tandem affinity purification was used in arabidopsis thaliana to identify cellular interactors of turnip mosaic virus (tumv) rna-dependent rna polymerase (rdrp). the heat shock cognate 70-3 (hsc70-3) and poly(a)-binding (pabp) host proteins were recovered and shown to interact with the rdrp in vitro. as previously shown for pabp, hsc70-3 was redistributed to nuclear and membranous fractions in infected plants and both rdrp interactors were co-immunoprecipitated from a membrane-enriched extract u ... | 2008 | 18222516 |
| sequence analysis of cp and hc-pro genes of turnip mosaic virus isolates from china. | fourteen isolates of turnip mosaic virus (tumv) were obtained from the leaves of diseased cruciferous plants in china. according host tests, the isolates were classified into b-host and br-host group. the nucleotide sequences of the coat protein (cp) and helper component proteinase (hc-pro) genes of the isolates were determined. the cp genes consisted of 864 nucleotides encoding a polypeptide of 288 amino acids. the hc-pro genes comprised 1374 nucleotides encoding a polypeptide of 458 amino acid ... | 2008 | 18459837 |
| eukaryotic elongation factor 1a interacts with turnip mosaic virus rna-dependent rna polymerase and vpg-pro in virus-induced vesicles. | eukaryotic elongation factor 1-alpha (eef1a) was identified as an interactor of turnip mosaic virus (tumv) rna-dependent rna polymerase (rdrp) and vpg-protease (vpg-pro) using tandem affinity purification and/or in vitro assays. subcellular fractionation experiments revealed that the level of eef1a substantially increased in membrane fractions upon tumv infection. replication of tumv occurs in cytoplasmic membrane vesicles, which are induced by 6k-vpg-pro. confocal microscopy indicated that eef1 ... | 2008 | 18501944 |
| characterization of conserved and novel micrornas and their targets, including a tumv-induced tir-nbs-lrr class r gene-derived novel mirna in brassica. | nine conserved mirna families and three potential novel mirnas in brassica rapa were identified from a small rna library. the expression patterns of some conserved mirnas had different tissue specificity in brassica and arabidopsis. one of the three potential mirnas, named bra-mir1885, was verified as a true functional mirna. it could be induced specifically by turnip mosaic virus (tumv) infection, and target tir-nbs-lrr class disease-resistant transcripts for cleavage. based on the hypothesis f ... | 2008 | 18558089 |
| turnip mosaic virus vpg interacts with arabidopsis thaliana eif(iso)4e and inhibits in vitro translation. | the interaction between turnip mosaic virus (tumv) viral protein linked to the genome (vpg) and arabidopsis thaliana eukaryotic initiation factor (iso)4e (eif(iso)4e) was investigated to address the influence of potyviral vpg on host cellular translational initiation. affinity chromatographic analysis showed that the region comprising amino acids 62-70 of vpg is important for the interaction with eif(iso)4e. in vitro translation analysis showed that the addition of vpg significantly inhibited tr ... | 2008 | 18582528 |
| identification and sequence analysis of potyviruses infecting crops in vietnam. | fifty-two virus isolates from 13 distinct potyvirus species infecting crops in vietnam were identified and the 3' region of each genome was sequenced. the viruses were: bean common mosaic virus (bcmv), potato virus y (pvy), sugarcane mosaic virus (scmv), sorghum mosaic virus (srmv), chilli veinal mottle virus (chivmv), zucchini yellow mosaic virus (zymv), leek yellow stripe virus (lymv), shallot yellow stripe virus (sysv), onion yellow dwarf virus (oydv), turnip mosaic virus (tumv), dasheen mosa ... | 2008 | 17906829 |
| a role for inositol hexakisphosphate in the maintenance of basal resistance to plant pathogens. | phytic acid (myo-inositol hexakisphosphate, insp6) is an important phosphate store and signal molecule in plants. however, low-phytate plants are being developed to minimize the negative health effects of dietary insp6 and pollution caused by undigested insp6 in animal waste. insp6 levels were diminished in transgenic potato plants constitutively expressing an antisense gene sequence for myo-inositol 3-phosphate synthase (ips, catalysing the first step in insp6 biosynthesis) or escherichia coli ... | 2008 | 18643983 |
| arabidopsis thaliana class ii poly(a)-binding proteins are required for efficient multiplication of turnip mosaic virus. | the poly(a)-binding protein (pabp) is an important translation initiation factor that binds to the polyadenylated 3' end of mrna. we have previously shown that pabp2 interacts with the rna-dependent rna polymerase (rdrp) and vpg-pro of turnip mosaic virus (tumv) within virus-induced vesicles. at least eight pabp isoforms are produced in arabidopsis thaliana, three of which (pabp2, pabp4 and pabp8) are highly and broadly expressed and probably constitute the bulk of pabp required for cellular fun ... | 2008 | 18753244 |
| genetic control of broad-spectrum resistance to turnip mosaic virus in brassica rapa (chinese cabbage). | the brassica rapa line rlr22 was resistant to eight diverse turnip mosaic virus (tumv) isolates. a b. rapa genetic map based on 213 marker loci segregating in 120 first back-cross (b(1)) individuals was established and aligned with the b. rapa genome reference map using some of the rflp probes. b(1) individuals were self-pollinated to produce b(1)s(1) families. the existence of two loci controlling resistance to tumv isolate cdn 1 was established from contrasting patterns of segregation for resi ... | 2007 | 17947545 |
| a developmentally linked, dramatic, and transient loss of virus from roots of arabidopsis thaliana plants infected by either of two rna viruses. | possible effects of host developmental stage on the amount of virus present in systemically infected plant tissues hitherto have received little attention. in this study, the pattern of virus accumulation over the plant lifespan has been examined in systemically invaded tissues of arabidopsis thaliana infected by either of two distinct (+)rna viruses: turnip mosaic virus, a member of potyvirus, and oilseed rape mosaic virus, a member of tobamovirus. quantitative analyses of virus coat protein an ... | 2007 | 17990966 |
| visualization of the interaction between the precursors of vpg, the viral protein linked to the genome of turnip mosaic virus, and the translation eukaryotic initiation factor iso 4e in planta. | the rna genome of turnip mosaic virus is covalently linked at its 5' end to a viral protein known as vpg. this protein binds to the translation eukaryotic initiation factor iso 4e [eif(iso)4e]. this interaction has been shown to be important for virus infection, although its exact biological function(s) has not been elucidated. in this study, we investigated the subcellular site of the vpg-eif(iso)4e interaction using bimolecular fluorescence complementation (bifc). as a first step, eif(iso)4e, ... | 2007 | 17079311 |
| reactivation of an integrated disabled viral vector using a cre-loxp recombination system in arabidopsis thaliana. | we developed an inactivated dna replicon of turnip mosaic virus (tumv), which was reactivated by a recombination event based on the cre-loxp system. viral replication was prevented by the insertion of a translation terminator sequence flanked by two loxp sites at the junction of the p1-hcpro-coding genes. in vitro recombination was tested with purified cre, which excised the floxed sequence from the tumv dna, leaving a single loxp site in the reactivated viral genome, and restored the open readi ... | 2007 | 17103245 |
| patterns of recombination in turnip mosaic virus genomic sequences indicate hotspots of recombination. | potyviruses have variable single-stranded rna genomes and many show clear evidence of recombination. this report studied the distribution of recombination sites in the genomes of 92 isolates of the potyvirus turnip mosaic virus (tumv); 42 came from the international gene sequence databases and an additional 50 complete genomic sequences were generated from field samples collected in europe and asia. the sequences were examined for evidence of recombination using seven different sequence comparis ... | 2007 | 17170463 |
| transient co-expression of post-transcriptional gene silencing suppressors and beta-glucuronidase in harvested lettuce leaf tissue does not improve recombinant protein accumulation in planta. | agrobacterium-mediated gene transfer was used to co-express three virus-derived post-transcriptional gene silencing (ptgs) suppressors, p19 from tomato bushy stunt virus and two species of helper component proteinase (hcpro) from tobacco etch virus (tev) and turnip mosaic virus, with beta-glucuronidase (gus) in harvested lettuce leaf tissue to investigate whether gus accumulation increases in the presence of ptgs suppressors. co-expression incubations were 3-5 days at 4 and 22 degrees c. gus act ... | 2007 | 17206371 |
| aba induction of mir159 controls transcript levels of two myb factors during arabidopsis seed germination. | upon seed imbibition, abscisic acid (aba) levels decrease to allow embryos to germinate and develop into seedlings. however, under abiotic stress conditions, aba levels remain high, and growth and development are arrested. several transcription factors, including abscisic acid-insensitive (abi)3 and abi5, are known to control this developmental checkpoint. here, we show that, in germinating arabidopsis thaliana seeds, aba induces the accumulation of microrna 159 (mir159) in an abi3-dependent fas ... | 2007 | 17217461 |
| identification of new isolates of turnip mosaic virus that cluster with less common viral strains. | turnip mosaic virus (tumv) was found infecting cultivated brassicas and wild and cultivated ornamental brassicaceae plants in different regions of spain. five new tumv isolates, originating from different host plant species (brassica cretica, brassica juncea, brassica napus, eruca vesicaria subsp. sativa and sisymbrium orientale), have been identified. the nucleotide sequences of the coat protein (cp) genes of the five isolates were determined. phylogenetic analysis of the cp sequences showed th ... | 2007 | 17347771 |
| sde5, the putative homologue of a human mrna export factor, is required for transgene silencing and accumulation of trans-acting endogenous sirna. | post-transcriptional gene silencing (ptgs) is a sequence-specific rna degradation process conserved in fungi, plants and animals. the trigger of the mechanism is double-stranded rna derived from transgenic or endogenous loci and formed by intra- or inter-molecular interactions of single-stranded rnas or the action of rna-dependent rna polymerases (rdrs). double-stranded rna from various sources is processed by one of the four dicer-like (dcl) proteins in arabidopsis, and the resulting short rnas ... | 2007 | 17397509 |
| spatial analysis of arabidopsis thaliana gene expression in response to turnip mosaic virus infection. | virus-infected leaf tissues comprise a heterogeneous mixture of cells at different stages of infection. the spatial and temporal relationships between sites of virus accumulation and the accompanying host responses, such as altered host gene expression, are not well defined. to address this issue, we utilized turnip mosaic virus (tumv) tagged with the green fluorescent protein to guide the dissection of infection foci into four distinct zones. the abundance of arabidopsis thaliana mrna transcrip ... | 2007 | 17427806 |
| evidence for targeting common sirna hotspots and gc preference by plant dicer-like proteins. | small interfering (si)rnas isolated from brassica juncea leaves infected by turnip mosaic virus (tumv) were characterized by cloning and sequencing. the tumv sirna population was dominated by 21 and 22-nt long species originated mainly from the same sirna hotspots, indicating operational similarity between the plant dicer-like (dcl) enzymes. robust gc bias was observed for tumv sirnas versus the virus genome, indicating that dcl was more likely to target gc-rich regions. furthermore, dicot micro ... | 2007 | 17597620 |
| genetic and molecular variability of a turnip mosaic virus population from horseradish (cochlearia armoracia l.). | variability and genetic structure of a novel turnip mosaic virus (tumv) population from horseradish (cochlearia armoracia l.) were examined. over 60 horseradish plants were tested to identify a total of 28 tumv isolates, constituting the cochlearia armoracia (car) tumv population. two subgroups of the car tumv isolates could be distinguished: subgroup n did not infect oilseed rape (brassica napus var. oleifera) cv. westar plants, while subgroup a infected these plants systemically. two types of ... | 2007 | 17666784 |
| the poly(a) binding protein is internalized in virus-induced vesicles or redistributed to the nucleolus during turnip mosaic virus infection. | poly(a) binding protein 2 (pabp2) of arabidopsis thaliana was previously shown to interact with vpg-pro of turnip mosaic virus (tumv) and may consequently play an important role during infection. subcellular fractionation experiments revealed that pabp2 was predominantly a cytoplasmic soluble protein in healthy plants. however, in tumv-infected plants, a subpopulation of pabp2 was membrane associated or was localized in the nucleus. confocal microscopy experiments indicated that pabp2 was partia ... | 2007 | 17670821 |
| effectiveness and stability of heterologous proteins expressed in plants by turnip mosaic virus vector at five different insertion sites. | the n-terminal (nt) regions of particular protein-coding sequences are generally used for in-frame insertion of heterologous open reading frames (orfs) in potyviral vectors for protein expression in plants. an infectious cdna clone of turnip mosaic virus (tumv) isolate yc5 was engineered at the generally used nt regions of hc-pro and cp, and other possibly permissive sites to investigate their effectiveness to express the gfp (jellyfish green fluorescent protein) and der p 5 (allergen from the d ... | 2007 | 17689817 |
| a phylogeographical study of the turnip mosaic virus population in east asia reveals an 'emergent' lineage in japan. | the genetic structure of populations of turnip mosaic virus (tumv) in east asia was assessed by making host range and gene sequence comparisons of 118 isolates utilizing a population genetic approach. most, but not all, isolates collected from brassica plants in china infected only brassica plants, whereas those from japan infected both brassica and raphanus (br) plants. analyses of the positions of recombination sites in five regions of the genomes (one third of the full sequence) of the many r ... | 2006 | 17107475 |
| the vpgpro protein of turnip mosaic virus: in vitro inhibition of translation from a ribonuclease activity. | a role for viral encoded genome-linked (vpg) proteins in translation has often been suggested because of their covalent attachment to the 5' end of the viral rna, reminiscent of the cap structure normally present on most eukaryotic mrnas. we tested the effect of turnip mosaic virus (tumv) vpgpro on translation of reporter rnas in in vitro translation systems. the presence of vpgpro in either wheat germ extract or rabbit reticulocyte lysate systems lead to inhibition of translation. the inhibitio ... | 2006 | 16647732 |
| a simplified method for cloning of short interfering rnas from brassica juncea infected with turnip mosaic potyvirus and turnip crinkle carmovirus. | rna silencing is a plant defense mechanism in which virus infected plants produce short interfering rnas (sirnas) derived from viral rna, that attack the virus at the post-transcriptional level. in a previous study on cymbidium ringspot tombusvirus (cymrsv) infection in nicotiana benthamiana, sirnas (determined by cloning and sequencing) predominantly originated from the sense (+) strand of the viral rna, suggesting that the majority of sirnas are produced through the direct cleavage of the viru ... | 2006 | 16815561 |
| interaction of genome-linked protein (vpg) of turnip mosaic virus with wheat germ translation initiation factors eifiso4e and eifiso4f. | the interaction between vpg of turnip mosaic virus and wheat germ eukaryotic translation initiation factors eifiso4e and eifiso4f (the complex of eifiso4e and eifiso4g) were measured and compared. the fluorescence quenching data showed the presence of one binding site on eifiso4e for vpg. scatchard analysis revealed the binding affinity (k(a)) and average binding sites (n) for vpg were (8.51 +/- 0.21) x 10(6) m(-1) and 1.0, respectively. the addition of eifiso4g to the eifiso4e increased the bin ... | 2006 | 16880203 |
| down-regulation of the 26s proteasome subunit rpn9 inhibits viral systemic transport and alters plant vascular development. | plant viruses utilize the vascular system for systemic movement. the plant vascular network also transports water, photosynthates, and signaling molecules and is essential for plant growth. however, the molecular mechanisms governing vascular development and patterning are still largely unknown. from viral transport suppressor screening using virus-induced gene silencing, we identified a 26s proteasome subunit, rpn9, which is required for broad-spectrum viral systemic transport. silencing of rpn ... | 2006 | 16905670 |
| expression of artificial micrornas in transgenic arabidopsis thaliana confers virus resistance. | plant micrornas (mirnas) regulate the abundance of target mrnas by guiding their cleavage at the sequence complementary region. we have modified an arabidopsis thaliana mir159 precursor to express artificial mirnas (amirnas) targeting viral mrna sequences encoding two gene silencing suppressors, p69 of turnip yellow mosaic virus (tymv) and hc-pro of turnip mosaic virus (tumv). production of these amirnas requires a. thaliana dicer-like protein 1. transgenic a. thaliana plants expressing amir-p69 ... | 2006 | 17057702 |
| binding analyses for the interaction between plant virus genome-linked protein (vpg) and plant translational initiation factors. | the turnip mosaic virus (tumv) genome-linked protein (vpg) and arabidopsis thaliana translation initiation factors were expressed and purified in order to investigate their binding properties and kinetics. affinity chromatography on m(7)gtp-sepharose showed that bound a. thaliana eif(iso)4e was eluted with crude tumv vpg. further column studies with purified vpg and other a. thaliana eif4e isoforms showed that vpg preferentially bound eif(iso)4e. structural data implicate trp-46 and trp-92 in ei ... | 2006 | 16300873 |
| konjak mosaic virus: the complete nucleotide sequence of the genomic rna and its comparison with other potyviruses. | konjak mosaic virus (komv) belongs to the genus potyvirus, family potyviridae. the complete nucleotide sequence of komv f isolate (komv f) was determined. the genome is 9,544 nucleotides long excluding the 3' terminal poly a tail and encodes a typical potyviral 350-kda polyprotein of 3,087 amino acids. phylogenetic analysis using known potyvirus polyproteins shows that komv constitutes a branch with yam mosaic virus, close to another branch including japanese yam mosaic virus, turnip mosaic viru ... | 2006 | 16538420 |
| tiered tests to assess the environmental risk of fitness changes in hybrids between transgenic crops and wild relatives: the example of virus resistant brassica napus. | over the last 20 years, there has been much research aimed at improving environmental risk assessment of transgenic crops. despite large amounts of data, decisions to allow or prohibit the release of transgenic crops remain confused and controversial. we argue that part of the reason for confusion is the lack of clear definitions of components of the environment that should be protected, and, as a consequence, there is no way to judge the relevance of data collected under the auspices of 'enviro ... | 2005 | 16634220 |
| mutations in turnip mosaic virus genomes that have adapted to raphanus sativus. | the genetic basis for virulence in potyviruses is largely unknown. earlier studies showed that there are two host types of turnip mosaic virus (tumv); the brassica/raphanus (br)-host type infects both brassica and raphanus systemically, whereas the brassica (b)-host type infects brassica fully and systemically, but not raphanus. the genetic basis of this difference has been explored by using the progeny of an infectious clone, p35tunos; this clone is derived from the uk1 isolate, which is of the ... | 2005 | 15659771 |
| selective involvement of members of the eukaryotic initiation factor 4e family in the infection of arabidopsis thaliana by potyviruses. | arabidopsis thaliana plants with mutations in the genes encoding eukaryotic initiation factor (eif4e) or isoform of eif4e (eif(iso)4e) were tested for susceptibility to clover yellow vein virus (clyvv), a member of the genus potyvirus. clyvv accumulated in both inoculated and upper uninoculated leaves of mutant plants lacking eif(iso)4e, but not in mutant plants lacking eif4e. in contrast, turnip mosaic virus (tumv), another member of the genus potyvirus, multiplied in mutant plants lacking eif4 ... | 2005 | 15710407 |
| a simplified method for obtaining plant viral rna for rt-pcr. | an easy and fast procedure (named the simple-direct-tube (sdt) method) was developed for preparing plant virus rna for cdna synthesis. the sdt method can be completed in approximately 15min and does not require the use of antiserum, filtering or centrifugation. the procedure to grind plant tissues in phosphate-buffered saline containing tween-20 (pbst) and to place the extract in a microfuge tube for a few minutes allow adsorption of the virus particles to the tube wall. the sap is then removed ... | 2005 | 15737418 |
| [distribution of rubisco and rca in brassica chinensis chloroplasts and effect of tumv-infection on their cellular localization]. | the cellular localizations of rubisco and rubisco activase (rca) in chinese cabbage (brassica chinensis l. cv. suzhou) leaves were investigated by immunogold-labeling electron microscopy. the results showed that rubisco and rca were mainly located in chloroplasts of mesophyll, guard cell of stomatal apparatus and parenchyma of vascular bundle. a high density of gold particles were localized preferentially to the chloroplast stroma. in contrast, there were no specific binding of gold particles de ... | 2005 | 15839204 |
| plant virus hc-pro is a determinant of eriophyid mite transmission. | the eriophyid mite transmitted wheat streak mosaic virus (wsmv; genus tritimovirus, family potyviridae) shares a common genome organization with aphid transmitted species of the genus potyvirus. although both tritimoviruses and potyviruses encode helper component-proteinase (hc-pro) homologues (required for nonpersistent aphid transmission of potyviruses), sequence conservation is low (amino acid identity, approximately 16%), and a role for hc-pro in semipersistent transmission of wsmv by the wh ... | 2005 | 15994799 |
| simultaneous production of two foreign proteins from a polyvirus-based vector. | with the aim of developing a biotechnological tool for the production of foreign proteins in plants, we first engineered an infectious turnip mosaic virus (tumv) cdna that contained the jellyfish green fluorescent protein (gfp) gene or the bacterial beta-glucuronidase (gus) gene (uida). two insertion sites were assessed, either between p1 and hcpro cistrons or pol and cp cistrons. in each construct, the junctions flanking the inserted gene coded for p1 and/or vpg-pro cleavage recognition site se ... | 2005 | 16022896 |
| aphid transmission of a potyvirus depends on suitability of the helper component and the n terminus of the coat protein. | the present study investigates the specificity of potyviruses for aphid species. two potyviruses differing in their host range were used: zucchini yellow mosaic virus (zymv) mainly infecting cucurbits and turnip mosaic virus (tumv) mainly infecting crucifers. two sets of aphids species were used as vectors, one polyphagous (myzus persicae and aphis gossypii) and the other from crucifers (brevicoryne brassicae and lipaphis erysimi). evidence is provided that the specificity between a vector and a ... | 2005 | 15503223 |
| fine genetic mapping of the tuni locus causing systemic veinal necrosis by turnip mosaic virus infection in arabidopsis thaliana. | in the pathosystem of turnip mosaic virus (tumv) and arabidopsis thaliana, two distinct symptoms (mosaic symptom and veinal necrosis) were observed that were dependent upon the combination of the tumv isolate and the arabidopsis ecotype. the col-0 ecotype developed mosaic symptoms after infection with the tumv isolate azu while the ler ecotype developed veinal necrosis after infection with the same tumv isolate. the ler phenotype is controlled by a single dominant gene tuni (tumv necrosis induce ... | 2004 | 15517145 |
| vpegamma exhibits a caspase-like activity that contributes to defense against pathogens. | caspases are a family of aspartate-specific cysteine proteases that play an essential role in initiating and executing programmed cell death (pcd) in metazoans. caspase-like activities have been shown to be required for the initiation of pcd in plants, but the genes encoding those activities have not been identified. vpegamma, a cysteine protease, is induced during senescence, a form of pcd in plants, and is localized in precursor protease vesicles and vacuoles, compartments associated with pcd ... | 2004 | 15530390 |
| comparisons of the genetic structure of populations of turnip mosaic virus in west and east eurasia. | the genetic structure of populations of turnip mosaic virus in eurasia was assessed by making host range and gene sequence comparisons of 142 isolates. most isolates collected in west eurasia infected brassica plants whereas those from east eurasia infected both brassica and raphanus plants. analyses of recombination sites (rss) in five regions of the genome (one third of the full sequence) showed that the protein 1 (p1 gene) had recombined more frequently than the other gene regions in both sub ... | 2004 | 15567435 |
| [accumulation of coat protein of turnip mosaic virus in host chloroplasts and its effect on ps ii activity]. | intact chloroplasts were isolated from chinese cabbage (brassica chinensis l. cv. suzhou) and mustard (b. juncea l. cv. wenzhou) leaves inoculated with turnip mosaic virus (tumv). the proteins attached to the surface of chloroplasts were digested, then the total proteins of chloroplasts were extracted. by analysis of the sds-page pattern, one extra protein band with the same mobility and molecular weight as tumv-coat protein was found in the chloroplasts of infected leaves. results of western bl ... | 2004 | 15583406 |
| a cysteine-rich plant protein potentiates potyvirus movement through an interaction with the virus genome-linked protein vpg. | we have identified a cellular factor that interacts with the virus genome-linked proteins (vpgs) of a diverse range of potyviruses. the factor, called potyvirus vpg-interacting protein (pvip), is a plant-specific protein with homologues in all the species examined, i.e., pea, arabidopsis thaliana, and nicotiana benthamiana. the sequence of pvip does not identify a specific function, although the existence of a "phd finger" domain may implicate the protein in transcriptional control through chrom ... | 2004 | 14963126 |
| interaction of vpg-pro of turnip mosaic virus with the translation initiation factor 4e and the poly(a)-binding protein in planta. | the viral protein linked to the genome (vpg) of turnip mosaic virus (tumv) interacts in vitro with the translation eukaryotic initiation factor (eif) 4e. in the present study, we investigated the consequence of tumv infection on eif4e expression. two isomers are present in plants, namely eif4e and eif(iso)4e. expression of the latter was detected in both tumv-infected and mock-inoculated brassica perviridis plants, but expression of eif4e was found only in infected plants. membranes from tumv-in ... | 2004 | 15039548 |
| functional replacement of wheat streak mosaic virus hc-pro with the corresponding cistron from a diverse array of viruses in the family potyviridae. | helper component-proteinase (hc-pro) of wheat streak mosaic virus strain sidney 81 (wsmv-sidney 81) was systematically replaced with the corresponding cistron derived from four strains of wsmv (type, tk1, cz, and el batán 3), the tritimovirus oat necrotic mottle virus (onmv), the rymoviruses agropyron mosaic virus (agmv) and hordeum mosaic virus (homv), or the potyviruses tobacco etch virus (tev) and turnip mosaic virus (tumv). these hc-pro proteins varied in amino acid sequence identity shared ... | 2004 | 15193921 |
| an important determinant of the ability of turnip mosaic virus to infect brassica spp. and/or raphanus sativus is in its p3 protein. | turnip mosaic virus (tumv, genus potyvirus, family potyviridae) infects mainly cruciferous plants. isolates tu-3 and tu-2r1 of tumv exhibit different infection phenotypes in cabbage (brassica oleracea l.) and japanese radish (raphanus sativus l.). infectious full-length cdna clones, ptuc and ptur1, were constructed from isolates tu-3 and tu-2r1, respectively. progeny virus derived from infections with ptuc induced systemic chlorotic and ringspot symptoms in infected cabbage, but no systemic infe ... | 2004 | 15218194 |
| inter- and intralineage recombinants are common in natural populations of turnip mosaic virus. | a recombination map of the genome of turnip mosaic virus (tumv) was assembled using data from 19 complete genomic sequences, previously reported, and a composite sample of three regions of the genome, one-third in total, of a representative asia-wide collection of 70 isolates. thus, a total of 89 isolates of worldwide origin was analysed for recombinants. eighteen recombination sites were found spaced throughout the 5' two-thirds of the genome, but there were only two in the 3' one-third; thus, ... | 2004 | 15302962 |
| rna silencing of the introduced coat protein gene of turnip mosaic virus confers broad-spectrum resistance in transgenic arabidopsis. | abstract the coat protein (cp) gene derived from turnip mosaic virus (tumv) isolate jo was introduced into arabidopsis thaliana and the resulting transgenic progenies were analyzed for resistance to tumv. transgenic arabidopsis plants with no detectable transcripts of the introduced cp gene exhibited complete resistance to tumv. there was no significant correlation between the resistance and the copy number of the transgene. instead, small interfering rnas (sirnas) were detected in these resista ... | 2004 | 18943905 |
| p1/hc-pro, a viral suppressor of rna silencing, interferes with arabidopsis development and mirna unction. | the molecular basis for virus-induced disease in plants has been a long-standing mystery. infection of arabidopsis by turnip mosaic virus (tumv) induces a number of developmental defects in vegetative and reproductive organs. we found that these defects, many of which resemble those in mirna-deficient dicer-like1 (dcl1) mutants, were due to the tumv-encoded rna-silencing suppressor, p1/hc-pro. suppression of rna silencing is a counterdefensive mechanism that enables systemic infection by tumv. t ... | 2003 | 12586064 |
| strains of turnip mosaic potyvirus as defined by the molecular analysis of the coat protein gene of the virus. | turnip mosaic virus (tumv) is a member of the potyvirus genus with a wide host range and highly variable in its biological characteristics. analysis of the cp gene sequences from databases, combined with the experimental analysis of the cp gene of further isolates, using data derived from sequence or restriction analysis, has allowed the genetic classification of 60 tumv isolates or sequences. two main genetic clusters mb (mostly brassica isolates) and mr (mostly radish isolates) were found, tog ... | 2003 | 12837555 |
| the phylogeny of turnip mosaic virus; comparisons of 38 genomic sequences reveal a eurasian origin and a recent 'emergence' in east asia. | the genomes of a representative world-wide collection of 32 turnip mosaic virus (tumv) isolates were sequenced and these, together with six previously reported sequences, were analysed. at least one-fifth of the sequences were recombinant. in phylogenetic analyses, using genomic sequences of japanese yam mosaic virus as an outgroup, the tumv sequences that did not show clear recombination formed a monophyletic group with four well-supported lineages. these groupings correlated with differences i ... | 2003 | 12859632 |
| genetic mapping of the novel turnip mosaic virus resistance gene turb03 in brassica napus. | a new source of resistance to the pathotype 4 isolate of turnip mosaic virus (tumv) cdn 1 has been identified in brassica napus (oilseed rape). analysis of segregation of resistance to tumv isolate cdn 1 in a backcross generation following a cross between a resistant and a susceptible b. napus line showed that the resistance was dominant and monogenic. molecular markers linked to this dominant resistance were identified using amplified fragment length polymorphism (aflp) and microsatellite bulk ... | 2003 | 12904865 |
| the dual role of the potyvirus p3 protein of turnip mosaic virus as a symptom and avirulence determinant in brassicas. | two isolates of the potyvirus turnip mosaic virus (tumv), uk 1 and cdn 1, differ both in their general symptoms on the susceptible propagation host brassica juncea and in their ability to infect b. napus lines possessing a variety of dominant resistance genes. the isolate cdn 1 produces a more extreme mosaic in infected brassica leaves than uk 1 and is able to overcome the resistance genes turb01, turb04, and turb05. the resistance gene turb03, in the b. napus line 22s, is effective against cdn ... | 2003 | 12971601 |
| molecular evolution of turnip mosaic virus: evidence of host adaptation, genetic recombination and geographical spread. | turnip mosaic virus (tumv), a species of the genus potyvirus, occurs worldwide. seventy-six isolates of tumv were collected from around the world, mostly from brassica and raphanus crops, but also from several non-brassica species. host tests grouped the isolates into one or other of two pathotypes; brassica (b) and brassica-raphanus (br). the nucleotide sequences of the first protein (p1) and coat protein (cp) genes of the isolates were determined. one-tenth of the isolates were found to have a ... | 2002 | 12029167 |
| characterisation of a potyvirus and a potexvirus from chinese scallion. | molecular analyses of viruses infecting chinese scallion (allium chinense g. don) showed that the plants did not contain any of the poty-, carla- or allexiviruses that are common in garlic plants in china. the complete sequences of a potyvirus and a potexvirus were determined and these were shown to represent different viruses from any in the databases. they could be transmitted mechanically to scallion but not to other allium species (including garlic) or to narcissus. the potyvirus, tentativel ... | 2002 | 12038680 |
| a fitness cost for turnip mosaic virus to overcome host resistance. | the relative fitness of the turnip mosaic virus (tumv) isolate uk 1 was compared with that of two other wildtype isolates cze 1 and cdn 1. the isolates cze 1 and cdn 1 are able to overcome the effect of the resistance gene turb01 and at least three other resistance sources that are effective against uk 1. comparisons were also made between the fitness of uk 1 and a recombinant virus with a single nucleotide change (v35tunos +5570 a>g) conferring the ability to overcome turb01 resistance. co-inoc ... | 2002 | 12076824 |
| loss-of-susceptibility mutants of arabidopsis thaliana reveal an essential role for eif(iso)4e during potyvirus infection. | the arabidopsis thaliana-potyvirus system was developed to identify compatibility and incompatibility factors involved during infection and disease caused by positive-strand rna viruses. several arabidopsis mutants with increased susceptibility to tobacco etch potyvirus (tev) were isolated previously, revealing a virus-specific resistance system in the phloem. in this study, arabidopsis mutants with decreased susceptibility to turnip mosaic potyvirus (tumv) were isolated. three independent mutan ... | 2002 | 12123581 |
| mutations in turnip mosaic virus p3 and cylindrical inclusion proteins are separately required to overcome two brassica napus resistance genes. | the brassica napus differential line 165 is resistant to infection by turnip mosaic virus (tumv) isolates belonging to pathotypes 1 and 3. nucleotide sequences of resistance-breaking mutants of pathotype 1 (uk 1), pathotype 3 (chn 12), and wild-type isolates have been determined. when the mutations identified were introduced into an infectious clone of uk 1, a single mutation in the viral p3 protein induced a hypersensitive (necrotic) response in inoculated leaves of line 165 plants. full system ... | 2002 | 12202205 |
| correlation of viral rna biosynthesis with glucose-6-phosphate dehydrogenase activity and host resistance. | changes in glucose-6-phosphate dehydrogenase (g6p dh; ec 1.1.1.49) activity caused by infection of tobacco ( nicotiana tabacum l.) leaves with potato virus y (pvy), cucumber mosaic virus, potato virus x, tobacco rattle virus and turnip mosaic virus, the subcellular localisation of g6p dh isozymes in mesophyll protoplasts derived from healthy and pvy-infected tobacco leaves, as well as g6p dh control and the relationship of its isozymes with the degree of tobacco resistance to pvy multiplication, ... | 2002 | 12244453 |
| potyviruses, novel and known, in cultivated and wild species of the family apiaceae in australia. | three potyviruses were identified by gene sequencing and found to be widespread in species of apiaceae in australia. only celery mosaic virus was found in celery crops and in one of 180 specimens of feral carrot ( daucus carota). another related but distinct novel potyvirus, carrot virus y, was the only virus found in carrot crops and all except one feral carrot. a more distantly related novel potyvirus, apium virus y, was found in plants of sea celery ( apium prostratum), cultivated parsley ( p ... | 2002 | 12376749 |
| zantedeschia mosaic virus causing leaf mosaic symptom in calla lily is a new potyvirus. | anovel virus, zantedeschia mosaic virus (zamv-kr), causing mosaic and malformation symptoms was isolated from calla lily ( zantedeschia spp.) in korea and its biological and molecular properties were characterized. the virus was distinct from dasheen mosaic virus, an araceae-infecting potyvirus, by serological and sequence analyses. multiple alignments of the cp amino acid sequence between the virus and other potyviruses showed 51.8 to 62.1% identity. phylogenetic analyses of the cp revealed tha ... | 2002 | 12491097 |
| the arabidopsis eukaryotic initiation factor (iso)4e is dispensable for plant growth but required for susceptibility to potyviruses. | an arabidopsis thaliana line bearing a transposon insertion in the gene coding for the isozyme form of the plant-specific cap-binding protein, eukaryotic initiation factor (iso) 4e (eif (iso) 4e), has been isolated. this mutant line completely lacks both eif(iso)4e mrna and protein, but was found to have a phenotype and fertility indistinguishable from wild-type plants under standard laboratory conditions. in contrast, the amount of the related eif4e protein was found to increase in seedling ext ... | 2002 | 12492835 |
| involvement of beet western yellows virus, cauliflower mosaic virus, and turnip mosaic virus in internal disorders of stored white cabbage. | abstract experiments over two growing seasons clearly showed that turnip mosaic virus (tumv) infection was associated with internal necrosis (sunken necrotic spots 5 to 10 mm in diameter) and beet western yellows virus (bwyv) infection was associated with collapse of leaf tissue at the margins (tipburn) in heads of stored white cabbage (brassica oleracea var. capitata). virtually no tipburn was seen in cv. polinius, whereas cv. impala was affected severely. internal necrotic spots were seen in b ... | 2002 | 18942959 |
| turnip mosaic virus and the quest for durable resistance. | summary taxonomy: turnip mosaic virus (tumv) is a member of the genus potyvirus (type species potato virus y) in the family potyviridae. to date, tumv is the only potyvirus known to infect brassicas. there are potyvirus isolates that appear serologically similar to tumv when tested with polyclonal antisera that do not readily infect brassicas (lesemann and vetten, 1985). physical properties: virions are approximately 720 x 15-20 nm flexuous rods (fig. 1) and are composed of 95% coat protein (cp) ... | 2002 | 20569337 |
| nickel increases susceptibility of a nickel hyperaccumulator to turnip mosaic virus. | hyperaccumulated ni can defend plant tissues against herbivores and pathogens. the effectiveness of this defense, however, has not been tested with a viral pathogen. turnip mosaic virus (tumv) accumulation was studied in two serpentine species of streptanthus with different ni uptake abilities. plants of a ni hyperaccumulator, milk-wort jewelflower (s. polygaloides gray), and a non-hyperaccumulator, plumed jewelflower (s. insignis jepson), were grown on ni-amended and unamended soils. plants wer ... | 2001 | 11215670 |
| a universal pcr primer to detect members of the potyviridae and its use to examine the taxonomic status of several members of the family. | a universal primer (sprimer: 5'-ggx aay aay agy ggx caz cc-3', x = a, g, c or t; y = t or c; z = a or g), designed from the consensus sequences that code for the conserved sequence gnnsgqp in the nib region of members of the family potyviridae, was used to amplify by rt-pcr the 3'-terminal genome regions from infected plant samples representing 21 different viruses in the family. sequencing of some of the fragments (c. 1.7 kb) showed that the type strain (attc pv-107) of oat necrotic mottle viru ... | 2001 | 11402861 |
| determination of the substrate specificity of turnip mosaic virus nia protease using a genetic method. | the rna genome of turnip mosaic potyvirus (tumv) encodes a large polyprotein that is processed to mature proteins by virus-encoded proteases. the tumv nia protease is responsible for the cleavage of the polyprotein at seven different locations. these cleavage sites are defined by a conserved sequence motif val-xaa-his-gln decreased, with the scissile bond located after gln. to determine the substrate specificity of the nia protease, amino acid sequences cleaved by the nia protease were obtained ... | 2001 | 11714990 |