Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
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| a cis element within flowering locus t mrna determines its mobility and facilitates trafficking of heterologous viral rna. | the arabidopsis flowering locus t (ft) gene encodes the mobile florigen essential for floral induction. while movement of the ft protein has been shown to occur within plants, systemic spread of ft mrna remains to be unequivocally demonstrated. utilizing novel rna mobility assay vectors based on two distinct movement-defective viruses, potato virus x and turnip crinkle virus, and an agroinfiltration assay, we demonstrate that nontranslatable ft mrna, independent of the ft protein, moves througho ... | 2009 | 19193810 |
| immunogenicity of hemagglutinin from a/bar-headed goose/qinghai/1a/05 and a/anhui/1/05 strains of h5n1 influenza viruses produced in nicotiana benthamiana plants. | highly pathogenic avian influenza (hpai) viruses of the h5n1 subtype have been identified as a potential pandemic threat by the world health organization (who). since 1997, these viruses have been spreading from asia to europe and africa with increasing genetic and antigenic diversities. vaccination is the preferred strategy for the prevention and control of influenza infections and the availability of a system for the rapid engineering and production of vaccines is required in the event of an i ... | 2009 | 19200814 |
| a single component two-valent lcrv-f1 vaccine protects non-human primates against pneumonic plague. | yersinia pestis continues to pose a threat as a potential biological weapon and is recognized by public health experts as a re-emerging infectious disease. therefore there is great interest in developing a safe and effective vaccine. vaccines against plague containing both the fraction 1 (f1) and v antigens of y. pestis have shown promise in protecting animal models against pneumonic plague, the deadliest form of the disease. here we report on a plague vaccine consisting of the f1 and lcrv antig ... | 2009 | 19200825 |
| an e7-based therapeutic vaccine protects mice against hpv16 associated cancer. | plant-derived vaccines represent an attractive strategy for cancer immunotherapy due to their relative safety and cost-effectiveness. we evaluated the anti-tumour activity of a nicotiana benthamiana produced vaccine candidate based on the non-transforming e7 protein of hpv-16 fused to beta-1,3-1,4-glucanase of clostridium thermocellum. two doses of vaccine at two week intervals were administered to groups of c57bl/6 mice starting 3 or 6 days after challenge with tumourigenic e7-expressing tc-1* ... | 2009 | 19200826 |
| differential expression of eight defensin genes of n. benthamiana following biotic stress, wounding, ethylene, and benzothiadiazole treatments. | eight nicotiana benthamiana defensin genes were identified that could be divided into two classes with class ii defensins being longer than class i defensins due to an additional acidic c-terminal domain. class i defensins were nbdef1.1, nbdef1.2, nbdef1.3, nbdef1.4, nbdef1.5, and nbdef1.6, and class ii were nbdef2.1 and nbdef2.2. relative rt-pcr showed that nbdef1.1, nbdef1.2, and nbdef1.4 had relatively similar expression levels in healthy leaves, stems, roots, flowers, and seeds. however, nbd ... | 2009 | 19214516 |
| nicotiana benthamiana protein, nbpcip1, interacting with potato virus x coat protein plays a role as susceptible factor for viral infection. | the interactions of viral coat protein (cp) and host factors play an important role in viral replication and/or host defense mechanism. in this study, we constructed nicotiana benthamiana cdna library to find host factors interacting with potato virus x (pvx) cp. using yeast two-hybrid assay, we screened 3.3 x 10(6) independent yeast transformants from n. benthamiana cdna library and identified six positive clones. one positive clone, named pvx cp-interacting protein 1 (nbpcip1), is a plant-spec ... | 2009 | 19215953 |
| inhibition of tobacco mosaic virus movement by expression of an actin-binding protein. | the tobacco mosaic virus (tmv) movement protein (mp) required for the cell-to-cell spread of viral rna interacts with the endoplasmic reticulum (er) as well as with the cytoskeleton during infection. whereas associations of mp with er and microtubules have been intensely investigated, research on the role of actin has been rather scarce. we demonstrate that nicotiana benthamiana plants transgenic for the actin-binding domain 2 of arabidopsis (arabidopsis thaliana) fimbrin (atfim1) fused to green ... | 2009 | 19218363 |
| the effector protein avr2 of the xylem-colonizing fungus fusarium oxysporum activates the tomato resistance protein i-2 intracellularly. | to promote host colonization, many plant pathogens secrete effector proteins that either suppress or counteract host defences. however, when these effectors are recognized by the host's innate immune system, they trigger resistance rather than promoting virulence. effectors are therefore key molecules in determining disease susceptibility or resistance. we show here that avr2, secreted by the vascular wilt fungus fusarium oxysporum f. sp. lycopersici (fol), shows both activities: it is required ... | 2009 | 19228334 |
| silencing of nicotiana benthamiana xrn4p exoribonuclease promotes tombusvirus rna accumulation and recombination. | the cytosolic 5'-to-3' exoribonuclease xrn1p plays a major role in recombination and degradation of tomato bushy stunt tombusvirus (tbsv) replicon (rep)rna in yeast, a model host (serviene, e., shapka, n., cheng, c.p., panavas, t., phuangrat, b., baker, j., and nagy, p.d., 2005. genome-wide screen identifies host genes affecting viral rna recombination. proc. natl. acad. sci. u. s. a. 102(30), 10545-10550.). to test if the plant cytosolic 5'-to-3' exoribonuclease xrn4p, similar to the yeast xrn1 ... | 2009 | 19232421 |
| recombinant-antibody-mediated resistance against tomato yellow leaf curl virus in nicotiana benthamiana. | tomato yellow leaf curl virus (tylcv) is a geminivirus species whose members cause severe crop losses in the tropics and subtropics. we report the expression of a single-chain variable fragment (scfv) antibody that protected nicotiana benthamiana plants from a prevalent iranian isolate of the virus (tylcv-ir). two recombinant antibodies (scfv-screp1 and scfv-screp2) interacting with the multifunctional replication initiator protein (rep) were obtained from phage display libraries and expressed i ... | 2009 | 19234665 |
| over-expression of putative transcriptional coactivator kelp interferes with tomato mosaic virus cell-to-cell movement. | tomato mosaic virus (tomv) encodes a movement protein (mp) that is necessary for virus cell-to-cell movement. we have demonstrated previously that kelp, a putative transcriptional coactivator of arabidopsis thaliana, and its orthologue from brassica campestris can bind to tomv mp in vitro. in this study, we examined the effects of the transient over-expression of kelp on tomv infection and the intracellular localization of mp in nicotiana benthamiana, an experimental host of the virus. in co-bom ... | 2009 | 19236566 |
| visualization of novel virulence activities of the xanthomonas type iii effectors avrbs1, avrbs3 and avrbs4. | xanthomonas campestris pv. vesicatoria secretes at least 20 effector proteins through the type iii secretion system directly into plant cells. in this study, we uncovered virulence activities of the effector proteins avrbs1, avrbs3 and avrbs4 using agrobacterium-mediated transient expression of the corresponding genes in nicotiana benthamiana, followed by microscopic analyses. we showed that, in addition to the nuclear-localized avrbs3, the effector avrbs1, which localizes to the plant cell cyto ... | 2009 | 19236567 |
| characterization and subcellular localization of an rna silencing suppressor encoded by rice stripe tenuivirus. | rice stripe virus (rsv) is a single-stranded (ss) rna virus belonging to the genus tenuivirus. rsv is present in many east asian countries and causes severe diseases in rice fields, especially in china. in this study, we analyzed six proteins encoded by the virus for their abilities to suppress rna silencing in plant using a green fluorescent protein (gfp)-based transient expression assay. our results indicate that ns3 encoded by rsv rna3, but not other five rsv encoded proteins, can strongly su ... | 2009 | 19251298 |
| roles and interactions of begomoviruses and satellite dnas associated with okra leaf curl disease in mali, west africa. | okra leaf curl disease (olcd) is a major constraint on okra (abelmoschus esculentus) production in west africa. two monopartite begomoviruses (okra virus-1 and okra virus-2), a betasatellite and a dna1 satellite are associated with olcd in mali. okra virus-1 is an isolate of okra yellow crinkle virus (oycrv), okra virus-2 is a recombinant isolate of cotton leaf curl gezira virus (clcugv) and the betasatellite is a variant of cotton leaf curl gezira betasatellite (clcugb). cloned dna of oycrv and ... | 2009 | 19264648 |
| variability in the level of rna silencing suppression caused by triple gene block protein 1 (tgbp1) from various potexviruses during infection. | rna silencing is an important defence mechanism against virus infection, and many plant viruses encode rna silencing suppressors as a counter defence. in this study, we analysed the rna silencing suppression ability of multiple virus species of the genus potexvirus. nicotiana benthamiana plants exhibiting rna silencing of a green fluorescent protein (gfp) transgene showed reversal of gfp fluorescence when systemically infected with potexviruses. however, the degree of gfp fluorescence varied amo ... | 2009 | 19264652 |
| pseudomonas syringae hrpp is a type iii secretion substrate specificity switch domain protein that is translocated into plant cells but functions atypically for a substrate-switching protein. | pseudomonas syringae delivers virulence effector proteins into plant cells via an hrp1 type iii secretion system (t3ss). p. syringae pv. tomato dc3000 hrpp has a c-terminal, putative t3ss substrate specificity switch domain, like yersinia yscp. a deltahrpp dc3000 mutant could not cause disease in tomato or elicit a hypersensitive response (hr) in tobacco, but the hr could be restored by expression of hrpp in trans. though hrpp is a relatively divergent protein in the t3ss of different p. syringa ... | 2009 | 19270091 |
| unusual long-distance movement strategies of potato mop-top virus rnas in nicotiana benthamiana. | the potato mop-top virus (pmtv) genome encodes replicase, movement, and capsid proteins on three different rna species that are encapsidated within tubular rod-shaped particles. previously, we showed that the protein produced on translational readthrough (rt) of the coat protein (cp) gene, cp-rt, is associated with one extremity of the virus particles, and that the two rnas encoding replicase and movement proteins can move long distance in the absence of the third rna (rna-cp) that encodes the c ... | 2009 | 19271953 |
| the magnaporthe oryzae avirulence gene avrpiz-t encodes a predicted secreted protein that triggers the immunity in rice mediated by the blast resistance gene piz-t. | the magnaporthe oryzae avirulence gene avrpiz-t activates immunity in a gene-for-gene fashion to rice mediated by the blast resistance gene piz-t. to dissect the molecular mechanism underlying their recognition, we initiated the cloning of avrpiz-t using a map-based cloning strategy. the avrpiz-t gene was delimited to an approximately 21-kb genomic fragment, in which six genes were predicted. complementation tests of each of these six candidate genes led to the final identification of avrpiz-t, ... | 2009 | 19271956 |
| molecular cloning and characterization of the promoter for the multiple stress-inducible gene bjchi1 from brassica juncea. | we have previously isolated a brassica juncea cdna encoding a novel chitinase bjchi1 with two chitin-binding domains (zhao and chye in plant mol biol 40:1009-1018, 1999). the expression of bjchi1 was highly inducible by methyl jasmonate (meja) treatment, wounding, caterpillar feeding, and pathogenic fungal infection. these observations suggest that the promoter of bjchi1 gene might contain specific cis-acting elements for stress responses. here, we report the cloning and characterization of the ... | 2009 | 19277702 |
| geminivirus al2 and l2 proteins suppress transcriptional gene silencing and cause genome-wide reductions in cytosine methylation. | geminiviruses replicate single-stranded dna genomes through double-stranded intermediates that associate with cellular histone proteins. unlike rna viruses, they are subject to rna-directed methylation pathways that target viral chromatin and likely lead to transcriptional gene silencing (tgs). here we present evidence that the related geminivirus proteins al2 and l2 are able to suppress this aspect of host defense. al2 and l2 interact with and inactivate adenosine kinase (adk), which is require ... | 2009 | 19279102 |
| transport of tmv movement protein particles associated with the targeting of rna to plasmodesmata. | the cell-to-cell movement of tobacco mosaic virus through plasmodesmata (pd) requires virus-encoded movement protein (mp). the mp targets pd through the endoplasmic reticulum (er)/actin network, whereas the intercellular movement of the viral rna genome has been correlated with the association of the mp with mobile, microtubule-proximal particles in cells at the leading front of infection as well as the accumulation of the protein on the microtubule network during later infection stages. to unde ... | 2008 | 19281527 |
| synergism and negative interference during co-infection of tomato and nicotiana benthamiana with two bipartite begomoviruses. | in brazil, at least eight begomoviruses including tomato rugose mosaic virus (tormv) and tomato yellow spot virus (toysv) infect tomatoes. toysv symptoms in tomato and nicotiana benthamiana appear earlier and are more severe compared to those of tormv. we investigated the role of several factors in this differential adaptation. to analyze infection kinetics, a single leaf was inoculated and subsequently detached after different periods of time. viral dna accumulation was quantified in plants, vi ... | 2009 | 19282016 |
| identification of an arabidopsis unknown small membrane protein targeted to mitochondria, chloroplasts, and peroxisomes. | in a functional genomic screen performed by combining an arabidopsis-yellow fluorescent protein (yfp)-fused complementary dna (cdna) library, rat fibroblasts as host and automatic microscopy, we found a short protein with a predictable trans-membrane domain encoded on chromosome 2. in rat fibroblasts, its pattern of distribution was to various organelle-like structures. from the databases, we learned that it has another family member in arabidopsis and homologs in several other plants, chlamydom ... | 2009 | 19283443 |
| suppression of bamboo mosaic virus accumulation by a putative methyltransferase in nicotiana benthamiana. | bamboo mosaic virus (bamv) is a 6.4-kb positive-sense rna virus belonging to the genus potexvirus of the family flexiviridae. the 155-kda viral replicase, the product of orf1, comprises an n-terminal s-adenosyl-l-methionine (adomet)-dependent guanylyltransferase, a nucleoside triphosphatase/rna 5'-triphosphatase, and a c-terminal rna-dependent rna polymerase (rdrp). to search for cellular factors potentially involved in the regulation of replication and/or transcription of bamv, the viral rdrp d ... | 2009 | 19297487 |
| plant-produced human growth hormone shows biological activity in a rat model. | plants have been shown to be efficient systems for expressing a wide range of recombinant proteins from various origins. here, using a plant virus-based expression vector to produce human growth hormone (hgh) in nicotiana benthamiana plants, we demonstrate, for the first time, that the plant-produced hgh (pphgh) is biologically active in a hypophysectomized rat model. we observed an average weight gain of approximately 17 g per animal in a group of 10 animals that were injected subcutaneously wi ... | 2009 | 19301254 |
| plant-derived recombinant f1, v, and f1-v fusion antigens of yersinia pestis activate human cells of the innate and adaptive immune system. | plague is still endemic in different regions of the world. current vaccines raise concern for their side effects and limited protection, highlighting the need for an efficacious and rapidly producible vaccine. f1 and v antigens of yersinia pestis, and f1-v fusion protein produced in nicotiana benthamiana administered to guinea pigs resulted in immunity and protection against an aerosol challenge of virulent y. pestis. we examined the effects of plant-derived f1, v, and f1-v on human cells of the ... | 2009 | 19309560 |
| a dna replicon system for rapid high-level production of virus-like particles in plants. | recombinant virus-like particles (vlps) represent a safe and effective vaccine strategy. we previously described a stable transgenic plant system for inexpensive production and oral delivery of vlp vaccines. however, the relatively low-level antigen accumulation and long-time frame to produce transgenic plants are the two major roadblocks in the practical development of plant-based vlp production. in this article, we describe the optimization of geminivirus-derived dna replicon vectors for rapid ... | 2009 | 19309755 |
| a unique virulence factor for proliferation and dwarfism in plants identified from a phytopathogenic bacterium. | one of the most important themes in agricultural science is the identification of virulence factors involved in plant disease. here, we show that a single virulence factor, tengu-su inducer (tengu), induces witches' broom and dwarfism and is a small secreted protein of the plant-pathogenic bacterium, phytoplasma. when tengu was expressed in nicotiana benthamiana plants, these plants showed symptoms of witches' broom and dwarfism, which are typical of phytoplasma infection. transgenic arabidopsis ... | 2009 | 19329488 |
| scaleable manufacture of hiv-1 entry inhibitor griffithsin and validation of its safety and efficacy as a topical microbicide component. | to prevent sexually transmitted hiv, the most desirable active ingredients of microbicides are antiretrovirals (arvs) that directly target viral entry and avert infection at mucosal surfaces. however, most promising arv entry inhibitors are biologicals, which are costly to manufacture and deliver to resource-poor areas where effective microbicides are urgently needed. here, we report a manufacturing breakthrough for griffithsin (grft), one of the most potent hiv entry inhibitors. this red algal ... | 2009 | 19332801 |
| cymbidium mosaic potexvirus isolate-dependent host movement systems reveal two movement control determinants and the coat protein is the dominant. | little is known about how plant viruses of a single species exhibit different movement behavior in different host species. two cymbidium mosaic potexvirus (cymmv) isolates, m1 and m2, were studied. both can infect phalaenopsis orchids, but only m1 can systemically infect nicotiana benthamiana plants. protoplast inoculation and whole-mount in situ hybridization revealed that both isolates can replicate in n. benthamiana; however, m2 was restricted to the initially infected cells. genome shuffling ... | 2009 | 19345971 |
| analysis of temperature modulation of plant defense against biotrophic microbes. | plant-pathogen interactions are known to be affected by environmental factors including temperature; however, the temperature effects have not been systematically studied in plant disease resistance. here, we characterized the effects of a moderate increase in temperature on resistance to bacterial pathogen pseudomonas syringae and two viral elicitors in arabidopsis thaliana and nicotiana benthamiana. both the basal and the resistance (r) gene-mediated defense responses to pseudomonas syringae a ... | 2009 | 19348568 |
| a comparative study of the involvement of 17 arabidopsis myosin family members on the motility of golgi and other organelles. | gene families with multiple members are predicted to have individuals with overlapping functions. we examined all of the arabidopsis (arabidopsis thaliana) myosin family members for their involvement in golgi and other organelle motility. truncated fragments of all 17 annotated arabidopsis myosins containing either the iq tail or tail domains only were fused to fluorescent markers and coexpressed with a golgi marker in two different plants. we tracked and calculated golgi body displacement rate ... | 2009 | 19369591 |
| studies of the role and function of barley stripe mosaic virus encoded proteins in replication and movement using gfp fusions. | this chapter describes techniques to investigate the localisation and function of virus-encoded proteins in plants using green fluorescent protein (gfp) transiently expressed from plasmids or infectious cdna reporter clones of barley stripe mosaic virus. virus movement and the localisation of gfp-tagged proteins in living cells were monitored by confocal laser scanning microscopy (clsm). in addition, gfp expression was imaged in transgenic plants where specific organelles or subcellular structur ... | 2009 | 19378124 |
| deletions in the repertoire of pseudomonas syringae pv. tomato dc3000 type iii secretion effector genes reveal functional overlap among effectors. | the gamma-proteobacterial plant pathogen pseudomonas syringae pv. tomato dc3000 uses the type iii secretion system to inject ca. 28 avr/hop effector proteins into plants, which enables the bacterium to grow from low inoculum levels to produce bacterial speck symptoms in tomato, arabidopsis thaliana, and (when lacking hopq1-1) nicotiana benthamiana. the effectors are collectively essential but individually dispensable for the ability of the bacteria to defeat defenses, grow, and produce symptoms ... | 2009 | 19381254 |
| a severe symptom phenotype in tomato in mali is caused by a reassortant between a novel recombinant begomovirus (tomato yellow leaf curl mali virus) and a betasatellite. | tomato production in west africa has been severely affected by begomovirus diseases, including yellow leaf curl and a severe symptom phenotype, characterized by extremely stunted and distorted growth and small deformed leaves. here, a novel recombinant begomovirus from mali, tomato yellow leaf curl mali virus (tylcmlv), is described that, alone, causes tomato yellow leaf curl disease or, in combination with a betasatellite, causes the severe symptom phenotype. tylcmlv is an old world monopartite ... | 2009 | 19400843 |
| 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 |
| gene silencing and virus resistance based on defective interfering constructs in transgenic nicotiana benthamiana is not linked to accumulation of sirna. | rna interference (rnai) was established in nicotiana benthamiana plants by introducing constructs containing a defective interfering (di) sequence from tomato bushy stunt virus (tbsv) in combination with a conserved sense-sequence from the target grapevine fanleaf virus (gflv). silencing in plants was confirmed by agrobacterium-mediated infiltration of a gfp-sensor containing the gflv-derived target sequence. the transgene-induced rnai led to silencing of the gfp-sensor and gfp fluorescence was ... | 2009 | 19419883 |
| transient co-expression for fast and high-yield production of antibodies with human-like n-glycans in plants. | plant-based transient expression is potentially the most rapid and cost-efficient system for the production of recombinant pharmaceutical proteins, but safety concerns associated with plant-specific n-glycosylation have hampered its adoption as a commercial production system. in this article, we describe an approach based on the simultaneous transient co-expression of an antibody, a suppressor of silencing and a chimaeric human beta1,4-galactosyltransferase targeted for optimal activity to the e ... | 2009 | 19422604 |
| impact of a defective rna 3 from cucumber mosaic virus on helper virus infection dynamics. | d rna 3yalpha (d3yalpha), a defective (d) rna 3 derived from the y strain of cucumber mosaic virus (cmv-y), was further characterized in combination with different helper viruses in the genus cucumovirus. interestingly, nicotiana benthamiana plants inoculated with cmv-d8 and d3yalpha developed systemic symptoms which were different from those induced by cmv-d8. to elucidate the potential effects of d rna 3 on virus infection on the basis of the original combination of cmv-y and d3yalpha, a point ... | 2009 | 19427011 |
| characterization of vitis vinifera npr1 homologs involved in the regulation of pathogenesis-related gene expression. | grapevine protection against diseases needs alternative strategies to the use of phytochemicals, implying a thorough knowledge of innate defense mechanisms. however, signalling pathways and regulatory elements leading to induction of defense responses have yet to be characterized in this species. in order to study defense response signalling to pathogens in vitis vinifera, we took advantage of its recently completed genome sequence to characterize two putative orthologs of npr1, a key player in ... | 2009 | 19432948 |
| evidence that the linker between the methyltransferase and helicase domains of potato virus x replicase is involved in homologous rna recombination. | recombination in rna viruses, one of the main factors contributing to their genetic variability and evolution, is a widespread phenomenon. in this study, an in vivo assay to characterize rna recombination in potato virus x (pvx), under high selection pressure, was established. agrobacterium tumefaciens was used to express in nicotiana benthamiana leaf tissue both a pvx isolate labeled with green fluorescent protein (gfp) containing a coat protein deletion mutation (deltacp) and a transcript enco ... | 2009 | 19439477 |
| identification and functional characterization of regions that can be crosslinked to rna in the helicase-like domain of bamv replicase. | the helicase-like domain of the bamboo mosaic virus replicase catalyzes the release of 5'-gamma-phosphate from both atp and 5'-triphosphated rna by an identical set of catalytic residues with a presumably larger binding pocket for rna. in this study, the peptidyl regions involved in rna binding were mapped by reversible formaldehyde crosslinking and mass spectrometry. eleven residues within these regions were examined by mutational analysis. h636a, y704a, and k706a greatly diminished the enzymat ... | 2009 | 19443005 |
| nitric oxide as a partner of reactive oxygen species participates in disease resistance to nectrotophic pathogen botryis cinerea in nicotiana benthamiana. | nitric oxide (no) is an essential regulatory molecule in plant immunity in synergy with reactive oxygen species (ros). however, little is known about the role of no in disease resistance to necrotrophic pathogens. no and oxidative bursts were induced during necrotrophic fungal pathogen botrytis cinerea and nicotiana benthamiana compatible interaction. histochemical analyses showed that both no and ros were produced in adjacent cells of invaded areas in n. benthamiana leaves. activation of salicy ... | 2009 | 19445587 |
| exploiting knowledge of r/avr genes to rapidly clone a new lz-nbs-lrr family of late blight resistance genes from potato linkage group iv. | in addition to the resistance to phytophthora infestans (rpi) genes rpi-blb1 and rpi-blb2, solanum bulbocastanum appears to harbor rpi-blb3 located at a major late blight resistance locus on lg iv, which also harbors rpi-abpt, r2, r2-like, and rpi-mcd1 in other solanum spp. here, we report the cloning and functional analyses of four rpi genes, using a map-based cloning approach, allele-mining strategy, gateway technology, and transient complementation assays in nicotiana benthamiana. rpi-blb3, r ... | 2009 | 19445588 |
| the xanthomonas campestris pv. vesicatoria type iii effector protein xopj inhibits protein secretion: evidence for interference with cell wall-associated defense responses. | the phytopathogenic bacterium xanthomonas campestris pv. vesicatoria uses the type iii secretion system (t3ss) to inject effector proteins into cells of its solanaceous host plants. it is generally assumed that these effectors manipulate host pathways to favor bacterial replication and survival. however, the molecular mechanisms by which type iii effectors suppress host defense responses are far from being understood. based on sequence similarity, xanthomonas outer protein j (xopj) is a member o ... | 2009 | 19445590 |
| trans-replication of, and competition between, dna beta satellites in plants inoculated with tomato yellow leaf curl china virus and tobacco curly shoot virus. | tomato yellow leaf curl china virus (tylccnv) y10 isolate (y10) and tobacco curly shoot virus (tbcsv) y35 isolate (y35), both obtained from yunnan province, were each found to be associated with a distinct species of satellite dna (dna beta). here, we demonstrate that both y10 dna beta (y10beta) and y35 dna beta (y35beta) were stably trans-replicated by the noncognate begomovirus, although the noncognate dna beta accumulated in plants at a lower level than did the cognate dna beta. in nicotiana ... | 2009 | 19453231 |
| functional redundancy in the arabidopsis cathepsin b gene family contributes to basal defence, the hypersensitive response and senescence. | cysteine proteases are required for programmed cell death (pcd) in animals. recent work in nicotiana benthamiana has implicated cathepsin b-like cysteine proteases in the hypersensitive response (hr) in plants, a form of pcd involved in disease resistance. here, we investigate the function and regulation of cathepsin b (cathb) genes in plant defence, and in both pathogen-inducible and developmental forms of pcd. single, double and triple knockout mutants were isolated for the three arabidopsis t ... | 2009 | 19453434 |
| the role of respiratory burst oxidase homologues in elicitor-induced stomatal closure and hypersensitive response in nicotiana benthamiana. | active oxygen species (aos) are central components of the defence reactions of plants against pathogens. plant respiratory burst oxidase homologues (rboh) of gp91(phox), a plasma membrane protein of the neutrophil nicotinamide adenine dinucleotide phosphate (nadph) oxidase, play a prominent role in aos production. the role of two rboh from nicotiana benthamiana, nbrboha and nbrbohb that encode plant nadph oxidase in the process of elicitor-induced stomatal closure and hypersensitive cell death i ... | 2009 | 19454596 |
| fluorometric quantification of green fluorescent protein in tobacco leaf extracts. | the main use of green fluorescent protein (gfp) is as a reporter system, where the existence of the protein is usually determined visually using fluorescent microscopy. although fluorescence-based quantification of gfp is possible, background fluorescence in plants and in plant extracts was observed by our group. another phenomenon we observed that makes quantification difficult is the increased level of gfp fluorescence in nicotiana benthamiana leaf extracts, probably the result of dimerization ... | 2009 | 19457429 |
| cell-to-cell trafficking, subcellular distribution, and binding to coat protein of broad bean wilt virus 2 vp37 protein. | broad bean wilt virus 2 (bbwv 2) is a member of the genus fabavirus of the family comoviridae. to date, a movement protein (mp) of bbwv 2 has not been described. here we demonstrate that the green fluorescent protein (gfp)-vp37 fusion protein can move from initial bombarded cells to neighboring cells in nicotiana benthamiana epidermal leaves. in addition, the gfp-vp37 fusion protein localizes as a halo around the nucleus and as punctate spots on the cell periphery in n. benthamiana epidermal lea ... | 2009 | 19463725 |
| three c-terminal phosphorylation sites in the abutilon mosaic virus movement protein affect symptom development and viral dna accumulation. | the abutilon mosaic virus (abmv, geminiviridae) dna b component encodes a movement protein (mp), which facilitates viral transport within plants and affects pathogenicity. the presence of phosphorylated serine and threonine residues was confirmed for mp expressed in yeast and nicotiana benthamiana by comparative western blot analysis using phospho-amino acid- and mp-specific immunodetection. mass spectrometry of yeast-derived mp identified three phosphorylation sites located in the c-terminal do ... | 2009 | 19464722 |
| overexpression of citrus junos mitochondrial citrate synthase gene in nicotiana benthamiana confers aluminum tolerance. | aluminum (al) toxicity is one of the major factors that limit plant growth in acid soils. al-induced release of organic acids into rhizosphere from the root apex has been identified as a major al-tolerance mechanism in many plant species. in this study, al tolerance of yuzu (citrus junos sieb. ex tanaka) was tested on the basis of root elongation and the results demonstrated that yuzu was al tolerant compared with other plant species. exposure to al triggered the exudation of citrate from the yu ... | 2009 | 19466450 |
| the multiplicity of infection of a plant virus varies during colonization of its eukaryotic host. | the multiplicity of infection (moi), i.e., the number of virus genomes that infect a cell, is a key parameter in virus evolution, as it determines processes such as genetic exchange among genomes, selection intensity on viral genes, epistatic interactions, and the evolution of multipartite viruses. in fact, the moi level is equivalent to the virus ploidy during genome expression. nevertheless, there are few experimental estimates of moi, particularly for viruses with eukaryotic hosts. here we es ... | 2009 | 19474097 |
| effects of dicer-like endoribonucleases 2 and 4 on infection of arabidopsis thaliana by cucumber mosaic virus and a mutant virus lacking the 2b counter-defence protein gene. | in tobacco and nicotiana benthamiana, limited cross-protection against cucumber mosaic virus strain fny (fny-cmv) was provided by prior inoculation with a deletion mutant lacking the 2b silencing-suppressor protein gene (fny-cmvdelta2b). cross-protection by fny-cmvdelta2b did not result from induction of systemic rna silencing. we investigated whether protection occurs through induction of localized rna silencing by using arabidopsis thaliana plants harbouring mutations in genes encoding the dic ... | 2009 | 19474248 |
| rna binding by the brome mosaic virus capsid protein and the regulation of viral rna accumulation. | viral capsid proteins (cps) can regulate gene expression and encapsulate viral rnas. low-level expression of the brome mosaic virus (bmv) cp was found to stimulate viral rna accumulation, while higher levels inhibited translation and bmv rna replication. regulation of translation acts through an rna element named the b box, which is also critical for the replicase assembly. the bmv cp has also been shown to preferentially bind to an rna element named slc that contains the core promoter for genom ... | 2009 | 19481091 |
| identification of domains of the tomato spotted wilt virus nsm protein involved in tubule formation, movement and symptomatology. | deletion and alanine-substitution mutants of the tomato spotted wilt virus nsm protein were generated to identify domains involved in tubule formation, movement and symptomatology using a heterologous tobacco mosaic virus expression system. two regions of nsm, g(19)-s(159) and g(209)-v(283), were required for both tubule formation in protoplasts and cell-to-cell movement in plants, indicating a correlation between these activities. three amino acid groups, d(154), eykk(205-208) and eeeee(284-288 ... | 2009 | 19481775 |
| optimization of the bioprocessing conditions for scale-up of transient production of a heterologous protein in plants using a chemically inducible viral amplicon expression system. | use of transient expression for the rapid, large-scale production of recombinant proteins in plants requires optimization of existing methods to facilitate scale-up of the process. we have demonstrated that the techniques used for agroinfiltration and induction greatly impact transient production levels of heterologous protein. a cucumber mosaic virus inducible viral amplicon (cmviva) expression system was used to transiently produce recombinant alpha-1-antitrypsin (raat) by co-infiltrating harv ... | 2009 | 19504593 |
| virus-induced gene silencing (vigs) in nicotiana benthamiana and tomato. | rna interference (rnai) is a highly specific gene-silencing phenomenon triggered by dsrna. this silencing mechanism uses two major classes of rna regulators: micrornas, which are produced from non-protein coding genes and short interfering rnas (sirnas). plants use rnai to control transposons and to exert tight control over developmental processes such as flower organ formation and leaf development. plants also use rnai to defend themselves against infection by viruses. consequently, many viruse ... | 2009 | 19516240 |
| selective binding of glutathione conjugates of fatty acid derivatives by plant glutathione transferases. | proteomic studies with arabidopsis thaliana have revealed that the plant-specific tau (u) class glutathione transferases (gsts) are selectively retained by s-hexylglutathione affinity supports. overexpression of members of the arabidopsis gst superfamily in escherichia coli showed that 25 of the complement of 28 gstus caused the aberrant accumulation of acylated glutathione thioesters in vivo, a perturbation that was not observed with other gst classes. each gstu caused a specific group of fatty ... | 2009 | 19520850 |
| boosted expression of the sars-cov nucleocapsid protein in tobacco and its immunogenicity in mice. | vaccines produced in plant systems are safe and economical; however, the extensive application of plant-based vaccines is mainly hindered by low expression levels of heterologous proteins in plant systems. here, we demonstrated that the post-transcriptional gene silencing suppressor p19 protein from tomato bushy stunt virus substantially enhanced the transient expression of recombinant sars-cov nucleocapsid (rn) protein in nicotiana benthamiana. the rn protein in the agrobacteria-infiltrated pla ... | 2009 | 19523911 |
| 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 |
| a novel cation-dependent o-methyltransferase involved in anthocyanin methylation in grapevine. | anthocyanins are major pigments in colored grape (vitis vinifera) berries, and most of them are monomethoxylated or dimethoxylated. we report here the functional characterization of an anthocyanin o-methyltransferase (aomt) from grapevine. the expression pattern in two cultivars with different anthocyanin methylation profiles (syrah and nebbiolo) showed a peak at start ripening (véraison), when the concentrations of all methylated anthocyanins begin to increase. the purified recombinant aomt pro ... | 2009 | 19525322 |
| cucurbit yellow stunting disorder virus p25 is a suppressor of post-transcriptional gene silencing. | post-transcriptional gene silencing (ptgs) degrades rna in a sequence-specific manner and is utilised by plants as a natural defence mechanism against virus invaders. two members of the genus crinivirus have been reported to encode suppressors and counter ptgs: sweet potato chlorotic stunt virus p22 and tomato chlorosis virus (tocv) p22, coat protein and coat protein minor. using an agrobacterium-mediated transient assay on nicotiana benthamiana wildtype and 16c plants, we screened four cucurbit ... | 2009 | 19540278 |
| suppression of local rna silencing is not sufficient to promote cell-to-cell movement of turnip crinkle virus in nicotiana benthamiana. | the biological relationship between suppression of rna silencing and virus movement poses an intriguing question in virus-plant interactions. here, we have used a local rna silencing assay, based on a movement-deficient turnip crinkle virus tcv/gfpdeltacp, to investigate the influence of silencing suppression by three different viral suppressors: the tcv 38k coat protein (cp), the 126k protein of tobacco mosaic virus (tmv), and p19 of tomato bushy stunt virus (tbsv) on cell-to-cell movement and ... | 2009 | 19568335 |
| a branched-chain aminotransferase may regulate hormone levels by affecting knox genes in plants. | branched-chain amino acid transaminases (bcats) play a crucial role in the metabolic pathway of leucine, isoleucine and valine by catalyzing the last step of synthesis and/or the initial step of degradation of these amino acids. in this study, we characterized a new bcat from nicotiana benthamiana (nbbcat, genebank accession no. eu194916), the deduced amino acid sequence of which exhibits a very high percentage of identity to the homologous enzymes from solanum tuberosum (stbcat-2, 91.5%) and ar ... | 2009 | 19568767 |
| maintenance of an old world betasatellite by a new world helper begomovirus and possible rapid adaptation of the betasatellite. | begomoviruses (family geminiviridae) cause major losses to crops throughout the tropical regions of the world. begomoviruses originating from the new world (nw) and the old world (ow) are genetically distinct. whereas the majority of ow begomoviruses have monopartite genomes and whereas most of these associate with a class of symptom-modulating satellites (known as betasatellites), the genomes of nw begomoviruses are exclusively bipartite and do not associate with satellites. here, we show for t ... | 2009 | 19570867 |
| subcellular localization of the barley stripe mosaic virus triple gene block proteins. | barley stripe mosaic virus (bsmv) spreads from cell to cell through the coordinated actions of three triple gene block (tgb) proteins (tgb1, tgb2, and tgb3) arranged in overlapping open reading frames (orfs). our previous studies (d. m. lawrence and a. o. jackson, j. virol. 75:8712-8723, 2001; d. m. lawrence and a. o. jackson, mol. plant pathol. 2:65-75, 2001) have shown that each of these proteins is required for cell-to-cell movement in monocot and dicot hosts. we recently found (h.-s. lim, j. ... | 2009 | 19570874 |
| interaction of tomato yellow leaf curl virus with diverse betasatellites enhances symptom severity. | the complete nucleotide sequence was determined for a begomovirus isolated from tomato exhibiting leaf curling and yellowing symptoms in tochigi prefecture in japan. the genome organization of this virus was similar to those of other old world monopartite begomoviruses. neither a dna betasatellite nor a dna-b component was detected. it had the highest total nucleotide sequence identity (99%) with tomato yellow leaf curl virus-israel[japan:tosa:2005] (tylcv-il[jr:tos:05]) and tylcv-israel[japan:h ... | 2009 | 19575277 |
| 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 |
| molecular characterization and pathogenicity of tomato yellow leaf curl virus in china. | several tomato production regions in china were surveyed for tomato yellow leaf curl disease (tylcd), and 31 tomato leaf samples showing tylcd-like symptoms were collected. the partial or full-length genomes of these isolates were sequenced and tomato yellow leaf curl virus (tylcv) was detected in shanghai, zhejiang, jiangsu shandong and hebei provinces of china. the tylcv isolates found in china share high sequence identity ([98%) and have more than 97% sequence identity with tylcvil[ il:reo] ( ... | 2009 | 19590945 |
| melandrium yellow fleck bromovirus infects arabidopsis thaliana and has genomic rna sequence characteristics that are unique among bromoviruses. | melandrium yellow fleck bromovirus (myfv) systemically infected arabidopsis thaliana, although the susceptibility of several a. thaliana accessions to myfv differed from their susceptibility to the other two bromoviruses infecting a. thaliana. we constructed full-length cdna clones of myfv genomic rnas 1, 2, and 3 and determined their complete nucleotide sequences. similar to broad bean mottle bromovirus, (1) the 5'-terminal nucleotide of the myfv genomic rnas was adenine, and (2) the "d-arm" wa ... | 2009 | 19597694 |
| in vitro propagation of plant virus using different forms of plant tissue culture and modes of culture operation. | plant virus accumulation was investigated in vitro using three different forms of plant tissue culture. suspended cells, hairy roots and shooty teratomas of nicotiana benthamiana were infected with tobacco mosaic virus (tmv) using the same initial virus:biomass ratio. viral infection did not affect tissue growth or morphology in any of the three culture systems. average maximum virus concentrations in hairy roots and shooty teratomas were similar and about an order of magnitude higher than in su ... | 2009 | 19616595 |
| wpp-domain proteins mimic the activity of the hsc70-1 chaperone in preventing mistargeting of rangap1-anchoring protein wit1. | arabidopsis (arabidopsis thaliana) tryptophan-proline-proline (wpp)-domain proteins, wpp1 and wpp2, are plant-unique, nuclear envelope-associated proteins of unknown function. they have sequence similarity to the nuclear envelope-targeting domain of plant rangap1, the gtpase activating protein of the small gtpase ran. wpp domain-interacting tail-anchored protein 1 (wit1) and wit2 are two arabidopsis proteins containing a coiled-coil domain and a c-terminal predicted transmembrane domain. they ar ... | 2009 | 19617588 |
| expression dynamics and ultrastructural localization of epitope-tagged abutilon mosaic virus nuclear shuttle and movement proteins in nicotiana benthamiana cells. | the geminivirus abutilon mosaic virus (abmv) encodes two proteins which are essential for viral spread within plants. the nuclear shuttle protein (nsp) transfers viral dna between the nucleus and cytoplasm, whereas the movement protein (mp) facilitates transport between cells through plasmodesmata and long-distance via phloem. an inducible overexpression system for epitope-tagged nsp and mp in plants yielded unprecedented amounts of both proteins. western blots revealed extensive posttranslation ... | 2009 | 19628237 |
| agroinoculation of the crinivirus, lettuce infectious yellows virus, for systemic plant infection. | lettuce infectious yellows virus (liyv) is phloem-limited, non-mechanically transmissible, and is transmitted to plants only by bemisia tabaci. here, we developed agroinoculation to deliver liyv to plants thereby obviating the need for b. tabaci. agroinfiltration of rna 1 containing a green fluorescent protein gene into nicotiana benthamiana leaves resulted in subliminal infections, as judged by green fluorescence. agroinfiltration of liyv wild-type rna 1 and 2 constructs resulted in systemic in ... | 2009 | 19632699 |
| tomato bushy stunt virus recombination guided by introduced microrna target sequences. | previously we described tomato bushy stunt virus (tbsv) vectors, which retained their capsid protein gene and were engineered with magnesium chelatase (chlh) and phytoene desaturase (pds) gene sequences from nicotiana benthamiana. upon plant infection, these vectors eventually lost the inserted sequences, presumably as a result of recombination. here, we modified the same vectors to also contain the plant mir171 or mir159 target sequences immediately 3' of the silencing inserts. we inoculated n. ... | 2009 | 19640975 |
| nbhb1, nicotiana benthamiana homeobox 1, is a jasmonic acid-dependent positive regulator of pathogen-induced plant cell death. | induction of cell death is an important component of plant defense against pathogens. there have been many reports on the role of phytohormones in pathogen-induced cell death, but jasmonic acid (ja) has not been implicated as a regulator of the response. here, we report the function of nbhb1, nicotiana benthamiana homeobox1, in pathogen-induced cell death in connection with ja signaling. involvement of nbhb1 in cell death was analysed by gain- and loss-of-function studies using agrobacterium-med ... | 2009 | 19645736 |
| regulation of defense gene expression by arabidopsis srfr1. | reduced growth and viability is a common phenotype of plants with constitutively activated pathogen defenses. one branch of the plant innate immunity system, effector-triggered immunity, is especially potent and requires tight control to enable normal plant development. while some facets of this control that directly regulate resistance protein abundance or activity have been documented, general control of effector-triggered signaling sensitivity is poorly understood. we recently identified supp ... | 2009 | 19649196 |
| 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 |
| molecular characterisation and infectivity of a "legumovirus" (genus begomovirus: family geminiviridae) infecting the leguminous weed rhynchosia minima in pakistan. | the legume yellow mosaic viruses (lymvs) that cause extensive losses to grain legumes across southern asia are an evolutionarily unusual group of begomoviruses (genus begomovirus; family geminiviridae) with bipartite genomes. all previously identified lymvs were isolated from leguminous crop species. here we have identified a virus related to the lymvs in a common weed, the legume rhynchosia minima originating from pakistan. analysis of the sequence of the virus shows it to be a typical bipartit ... | 2009 | 19664665 |
| characterization of the cassava geminivirus transcription activation protein putative nuclear localization signal. | the geminivirus transcription activation protein (trap) localizes to the nucleus and contains a putative nuclear localization signal (nls) ((28)prrrr(32)) on the n-terminus. the role of individual residues of this putative nls on nuclear localization and symptom induction was investigated using trap of east african cassava mosaic cameroon virus (eacmcv). subcellular localization was conducted using the green fluorescent protein (gfp). results showed that the proline residue at position 28 (pro-2 ... | 2009 | 19665038 |
| proteolysis of a negative regulator of innate immunity is dependent on resistance genes in tomato and nicotiana benthamiana and induced by multiple bacterial effectors. | rpm1-interacting protein 4 (rin4), a negative regulator of the basal defense response in plants, is targeted by multiple bacterial virulence effectors. we show that rin4 degradation is induced by the effector avrpto from pseudomonas syringae and that this degradation in solanaceous plants is dependent on the resistance protein, pto, a protein kinase, and prf, a nucleotide binding site-leucine-rich repeat protein. our data demonstrate overlap between two of the best-characterized pathways for rec ... | 2009 | 19671880 |
| protein mislocalization in plant cells using a gfp-binding chromobody. | a key challenge in cell biology is to directly link protein localization to function. the green fluorescent protein (gfp)-binding protein, gbp, is a 13-kda soluble protein derived from a llama heavy chain antibody that binds with high affinity to gfp as well as to some gfp variants such as yellow fluorescent protein (yfp). a gbp fusion to the red fluorescent protein (rfp), a molecule termed a chromobody, was previously used to trace in vivo the localization of various animal antigens. in this st ... | 2009 | 19686537 |
| a novel mapkk involved in cell death and defense signaling. | a high-throughput in planta overexpression screen of a nicotiana benthamiana cdna library identified a mitogen activated protein kinase kinase (mapkk), nbmkk1, as a potent inducer of hypersensitive response (hr)-like cell death. nbmkk1-mediated cell death was attenuated in plants whereby expression of nbsipk, an ortholog of tobacco sipk and arabidopsis atmpk6, was knocked down by virus-induced gene silencing (vigs), suggesting that nbmkk1 functions upstream of nbsipk. in accordance with this res ... | 2007 | 19704612 |
| distinct rna motifs mediate systemic rna trafficking. | systemic rna trafficking is emerging as a new paradigm in gene regulation at the whole plant level. the mechanisms that ensure delivery of all sorts of rnas to their respective cellular destinations remain poorly understood. several lines of research suggest that specific sequence/structural motif(s) within an rna directs its trafficking. the first motif was identified in potato spindle tuber viroid (pstvd), which mediates trafficking from bundle sheath to mesophyll in young tobacco leaves. our ... | 2008 | 19704772 |
| the colletotrichum orbiculare ssd1 mutant enhances nicotiana benthamiana basal resistance by activating a mitogen-activated protein kinase pathway. | plant basal resistance is activated by virulent pathogens in susceptible host plants. a colletotrichum orbiculare fungal mutant defective in the ssd1 gene, which regulates cell wall composition, is restricted by host basal resistance responses. here, we identified the nicotiana benthamiana signaling pathway involved in basal resistance by silencing the defense-related genes required for restricting the growth of the c. orbiculare mutant. only silencing of map kinase kinase2 or of both salicylic ... | 2009 | 19706796 |
| defining the determinants for dual targeting of amino acyl-trna synthetases to mitochondria and chloroplasts. | most of the organellar amino acyl-trna synthetases (aarss) are dually targeted to both mitochondria and chloroplasts using dual targeting peptides (dtps). we have investigated the targeting properties and domain structure of dtps of seven aarss by studying the in vitro and in vivo import of n-terminal deleted constructs of dtps fused to green fluorescent protein. the deletion constructs were designed based on prediction programs, targetp and predotar, as well as logoplots derived from organellar ... | 2009 | 19733576 |
| regions of the cf-9b disease resistance protein able to cause spontaneous necrosis in nicotiana benthamiana lie within the region controlling pathogen recognition in tomato. | the tomato cf-9 and cf-9b genes both confer resistance to the leaf mold fungus cladosporium fulvum but only cf-9 confers seedling resistance and recognizes the avirulence (avr) protein avr9 produced by c. fulvum. using domain swaps, leucine-rich repeats (lrr) 5 to 15 of cf-9 were shown to be required for cf-9-specific resistance to c. fulvum in tomato, and the entire n-terminus up to lrr15 of cf-9b was shown to be required for cf-9b-specific resistance. finer domain swaps showed that nine amino- ... | 2009 | 19737095 |
| rnai-mediated transgenic tospovirus resistance broken by intraspecies silencing suppressor protein complementation. | extension of an inverted repeat transgene cassette, containing partial nucleoprotein (n) gene sequences from four different tomato-infecting tospovirus spp. with a partial n gene sequence from the tomato strain of tomato yellow ring virus (tyrv-t), renders transgenic nicotiana benthamiana plants additionally resistant to this strain but not to the soybean strain of this tospovirus sp. (tyrv-s), both strains exhibiting 14.4% nucleotide sequence divergence in their n genes. surprisingly, coinocula ... | 2009 | 19737098 |
| complementation analysis of triple gene block of potato virus s (pvs) revealed its capability to support systemic infection and aphid transmissibility of recombinant potato virus x. | triple gene block (tgb) sequences derived from isolates of ordinary potato virus s (pvs-o) and chenopodium-systemic (pvs-cs) were analyzed. although the tgb sequences did not reveal any specific difference within the 7k protein, some specific differences within the 25k and 12k orfs were found. in order to investigate a possible functional divergence of pvs-o and pvs-cs tgb variants, these genes were propagated in chimeric potato virus x (pvx). both pvs tgb variants partly complemented pvx tgb in ... | 2009 | 19748533 |
| molecular characterization and experimental host range of an isolate of wissadula golden mosaic st. thomas virus. | partial genome segments of a begomovirus were previously amplified from wissadula amplissima exhibiting yellow-mosaic and leaf-curl symptoms in the parish of st. thomas, jamaica and this isolate assigned to a tentative begomovirus species, wissadula golden mosaic st. thomas virus. to clone the complete genome of this isolate of wissadula golden mosaic st. thomas virus, abutting primers were designed to pcr amplify its full-length dna-a and dna-b components. sequence analysis of the complete bego ... | 2009 | 19768650 |
| production and characterization of an orally immunogenic plasmodium antigen in plants using a virus-based expression system. | increasing numbers of plant-made vaccines and pharmaceuticals are entering the late stage of product development and commercialization. despite the theoretical benefits of such production, expression of parasite antigens in plants, particularly those from plasmodium, the causative parasites for malaria, have achieved only limited success. we have previously shown that stable transformation of tobacco plants with a plant-codon optimized form of the plasmodium yoelii merozoite surface protein 4/5 ... | 2009 | 19781007 |
| in planta expression screens of phytophthora infestans rxlr effectors reveal diverse phenotypes, including activation of the solanum bulbocastanum disease resistance protein rpi-blb2. | the irish potato famine pathogen phytophthora infestans is predicted to secrete hundreds of effector proteins. to address the challenge of assigning biological functions to computationally predicted effector genes, we combined allele mining with high-throughput in planta expression. we developed a library of 62 infection-ready p. infestans rxlr effector clones, obtained using primer pairs corresponding to 32 genes and assigned activities to several of these genes. this approach revealed that 16 ... | 2009 | 19794118 |
| expression of hemagglutinin-neuraminidase glycoprotein of newcastle disease virus in agroinfiltrated nicotiana benthamiana plants. | the worldwide need for producing safer and less expensive vaccines with minor manufacture and processing requirements, together with the advances made through biotechnology, has promoted the development of efficient alternative tools to conventional vaccines. one of these is the use of plants or plant cell culture as production platforms of vaccine antigens with potential use as immunogens. we have already described the use of transgenic potato plants as immunogens against newcastle disease viru ... | 2009 | 19799942 |
| processing of mirna precursors. | plant microrna (mirna) processing requires at least two cleavage steps of respective precursors. the first cleavage step is from pri-mirna to pre-mirna, and the second cleavage step is from pre-mirna to mature mirna. using northern blot analysis, we previously showed that the rnase iii enzyme dicer-like protein 1 (dcl1) and the double-stranded rna-binding (drb) protein hyl1 are involved in the processing reactions of mirna precursors. the processing of plant mirnas differs from that of animal mi ... | 2010 | 19802599 |
| transient assays for the analysis of mirna processing and function. | transient assays provide a convenient alternative to stable transformation. for small rna analysis in plants, the most widely used method, commonly named agroinfiltration, makes use of agrobacterium tumefaciens to deliver transgenes into leaf cells of nicotiana benthamiana. compared to the generation of stably transformed plants, agroinfiltration is more rapid, and samples can be analyzed a few days after inoculation. agroinfiltration has been used successfully in many different applications, in ... | 2010 | 19802601 |
| differing requirements for actin and myosin by plant viruses for sustained intercellular movement. | the actin cytoskeleton has been implicated in the intra- and intercellular movement of a growing number of plant and animal viruses. however, the range of viruses influenced by actin for movement and the mechanism of this transport are poorly understood. here we determine the importance of microfilaments and myosins for the sustained intercellular movement of a group of rna-based plant viruses. we demonstrate that the intercellular movement of viruses from different genera [tobacco mosaic virus ... | 2009 | 19805075 |
| loss of the plant dead-box protein ise1 leads to defective mitochondria and increased cell-to-cell transport via plasmodesmata. | plants have intercellular channels, plasmodesmata (pd), that span the cell wall to enable cell-to-cell transport of micro- and macromolecules. we identified an arabidopsis thaliana embryo lethal mutant increased size exclusion limit 1 (ise1) that results in increased pd-mediated transport of fluorescent tracers. the ise1 mutants have a higher frequency of branched and twinned pd than wild-type embryos. silencing of ise1 in mature nicotiana benthamiana leaves also leads to increased pd transport, ... | 2009 | 19805190 |
| transcriptional changes and oxidative stress associated with the synergistic interaction between potato virus x and potato virus y and their relationship with symptom expression. | many virus diseases of economic importance to agriculture result from mixtures of different pathogens invading the host at a given time. this contrasts with the relatively scarce studies available on the molecular events associated with virus-host interactions in mixed infections. compared with single infections, co-infection of nicotiana benthamiana with potato virus x (pvx) and potato virus y (pvy) resulted in increased systemic symptoms (synergism) that led to necrosis of the newly emerging l ... | 2009 | 19810812 |
| identification of two rna silencing suppressors from banana bunchy top virus. | in order to suppress rna silencing, many plant and some animal viruses encode rna silencing suppressors to achieve infection. in this study, we report that b3 and b4, encoded by dna3 and dna4 of banana bunchy top virus (bbtv), exhibit rna silencing suppression activity. b3 and b4 were able to increase the transient expression of green fluorescent protein (gfp) and dramatically enhanced the pathogenicity of potato virus x (pvx) in nicotiana benthamiana. b4 was able to reverse established gene sil ... | 2009 | 19816653 |