Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
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| cytosine methylation is associated with rna silencing in silenced plants but not with systemic and transitive rna silencing through grafting. | rna silencing is often associated with methylation of the target gene. the dna methylation level of transgenes was investigated in post-transcriptionally silenced or non-silenced nicotiana benthamiana carrying either the 5' region (200 or 400 bp) or the entire region of the coat protein gene (cp, including the 3' non-translated region) of sweet potato feathery mottle virus. higher levels of transgene cytosine methylation were observed in both symmetrical (cpg, cpnpg) and non-symmetrical (cphph) ... | 2007 | 17521830 |
| physical association of the nb-lrr resistance protein rx with a ran gtpase-activating protein is required for extreme resistance to potato virus x. | nucleotide binding leucine-rich repeat (nb-lrr) proteins play an important role in plant and mammalian innate immunity. in plants, these resistance proteins recognize specific pathogen-derived effector proteins. recognition subsequently triggers a rapid and efficient defense response often associated with the hypersensitive response and other poorly understood processes that suppress the pathogen. to investigate mechanisms associated with the activation of disease resistance responses, we invest ... | 2007 | 17526750 |
| geminivirus pathogenicity protein c4 interacts with arabidopsis thaliana shaggy-related protein kinase atsketa, a component of the brassinosteroid signalling pathway. | beet curly top virus (bctv) c4 interacted with two members of the shaggy-related protein kinase family (atsketa and atskzeta) and a putative leucine-rich repeat receptor-like kinase (lrr-rlk) in a yeast two-hybrid assay. tomato golden mosaic virus (tgmv) ac4 also bound with similar efficiency to atsketa and atskzeta but was unable to interact with the lrr-rlk. bctv c4 interaction with atsketa was confirmed using an in vitro binding assay. the protein kinases were capable of autophosphorylation i ... | 2007 | 17280695 |
| in vivo packaging of brome mosaic virus rna3, but not rnas 1 and 2, is dependent on a cis-acting 3' trna-like structure. | the four encapsidated rnas of brome mosaic virus (bmv; b1, b2, b3, and b4) contain a highly conserved 3' 200-nucleotide (nt) region encompassing the trna-like structure (tls) which is required for packaging in vitro (y. g. choi, t. w. dreher, and a. l. n. rao, proc. natl. acad. sci. usa 99:655-660, 2002). to validate these observations in vivo, we performed packaging assays using agrobacterium-mediated transient expression of rnas and coat protein (cp) (p. annamalai and a. l. n. rao, virology 33 ... | 2007 | 17005656 |
| translational control of recombinant human acetylcholinesterase accumulation in plants. | codon usage differences are known to regulate the levels of gene expression in a species-specific manner, with the primary factors often cited to be mrna processing and accumulation. we have challenged this conclusion by expressing the human acetylcholinesterase coding sequence in transgenic plants in its native gc-rich sequence and compared to a matched sequence with (dicotyledonous) plant-optimized codon usage and a lower gc content. | 2007 | 17537261 |
| immunogenicity of a subunit vaccine against bacillus anthracis. | the current approved vaccine against anthrax is based on protective antigen (pa) of bacillus anthracis, requires six injections over an 18-month period and has a known history of side effects. therefore, there is significant effort towards developing an improved vaccine against b. anthracis. here we separately engineered and expressed domain 4 of pa (pad4) and domain 1 of lethal factor (lfd1) as fusions to lichenase (lickm), a thermostable enzyme from clostridium thermocellum, and transiently ex ... | 2007 | 17280756 |
| early events in the pathogenicity of pseudomonas syringae on nicotiana benthamiana. | conserved microbial molecules known as pamps (pathogen-associated molecular patterns) elicit defence responses in plants through extracellular receptor proteins. one important pamp is the flagellin protein derived from motile bacteria. we show here that the solanaceous species nicotiana benthamiana perceives the flagellin proteins of both pathogenic and non-host species of pseudomonas syringae. the response to flagellin required a gene closely related to that encoding the arabidopsis thaliana fl ... | 2007 | 17217460 |
| indirect activation of a plant nucleotide binding site-leucine-rich repeat protein by a bacterial protease. | nucleotide binding site-leucine-rich repeat (nbs-lrr) proteins mediate pathogen recognition in both mammals and plants. the molecular mechanisms by which pathogen molecules activate nbs-lrr proteins are poorly understood. here we show that rps5, a nbs-lrr protein from arabidopsis, is activated by avrpphb, a bacterial protease, via an indirect mechanism. when transiently expressed in nicotiana benthamiana leaves, full-length rps5 protein triggered programmed cell death, but only when coexpressed ... | 2007 | 17277084 |
| quantitative analysis of efficient endogenous gene silencing in nicotiana benthamiana plants using tomato bushy stunt virus vectors that retain the capsid protein gene. | tomato bushy stunt virus (tbsv) coat protein (cp) replacement vectors have been used previously to silence transgenes (e.g., the green fluorescent protein gene) but have not been effective for silencing endogenous plant genes. new tbsv vectors which retained the cp gene were developed by engineering an xhoi restriction site in three positions (3f, ceb, and cea) of the ptbsv-100 infectious clone. magnesium chelatase (chlh) and phytoene desaturase (pds) were chosen as targets for endogenous gene s ... | 2007 | 17555269 |
| dna abrasion onto plants is an effective method for geminivirus infection and virus-induced gene silencing. | geminiviruses belong to a rapidly growing group of plant pathogens that contribute to crop losses in tropical and subtropical areas of the world. geminivirus infection is a model for plant dna replication and virus/host interactions. geminiviruses are also used as vectors to induce silencing of endogenous genes in several plant species. a method was analyzed for inoculating geminiviruses using plasmid dna rubbed onto leaves in the presence of an abrasive (dna abrasion). although the use of dna a ... | 2007 | 17337069 |
| identification and characterization of a new virus in the genus potyvirus from wild populations of angelica lucida l. and a. genuflexa nutt., family apiaceae. | a novel potyvirus was discovered in angelica lucida l. (wild celery) and a. genuflexa nutt. (kneeling angelica) (family apiaceae) in the matanuska- susitna valley, alaska. the experimental plant host range of the virus included species in three families: chenopodiaceae (chenopodium amaranticolor coste et reyn and chenopodium quinoa willd.), solanaceae (nicotiana benthamiana domin, and n. clevlandii gray.), and apiaceae (anethum graveolens l., apium graveolens l. var. dulce (miller)), daucus caro ... | 2007 | 17558540 |
| a functional genetic assay for nuclear trafficking in plants. | the receptor importin-alpha mediates the nuclear import of functionally diverse cargo proteins that contain arginine/lysine-rich nuclear localization signals (nlss). functional homologs of importin-alpha have been characterized in a wide range of species including yeast, human and plants. however, the differential cargo selectivity of plant importin-alpha homologs has not been established. to advance nuclear import studies conducted in plant cells, we have developed a method that allows importin ... | 2007 | 17346267 |
| arabidopsis cytochrome p450 monooxygenase 71a13 catalyzes the conversion of indole-3-acetaldoxime in camalexin synthesis. | camalexin (3-thiazol-2-yl-indole) is an indole alkaloid phytoalexin produced by arabidopsis thaliana that is thought to be important for resistance to necrotrophic fungal pathogens, such as alternaria brassicicola and botrytis cinerea. it is produced from trp, which is converted to indole acetaldoxime (iaox) by the action of cytochrome p450 monooxygenases cyp79b2 and cyp79b3. the remaining biosynthetic steps are unknown except for the last step, which is conversion of dihydrocamalexic acid to ca ... | 2007 | 17573535 |
| use of pentapeptide-insertion scanning mutagenesis for functional mapping of the plum pox virus helper component proteinase suppressor of gene silencing. | helper component proteinase (hc-pro) of plum pox virus is a multifunctional potyvirus protein that has been examined intensively. in addition to its involvement in aphid transmission, genome amplification and long-distance movement, it is also one of the better-studied plant virus suppressors of rna silencing. the first systematic analysis using pentapeptide-insertion scanning mutagenesis of the silencing suppression function of a potyvirus hc-pro is presented here. sixty-three in-frame insertio ... | 2007 | 17325375 |
| rna-binding proteins that inhibit rna virus infection. | arrays of >5,000 saccharomyces cerevisiae proteins were screened to identify proteins that can preferentially bind a small rna hairpin that contains a clamped adenine motif (cam). a cam is required for the replication of brome mosaic virus (bmv), a plant-infecting rna virus that can replicate in s. cerevisiae. several hits were selected for further characterization in nicotiana benthamiana. pseudouridine synthase 4 (pus4) and the actin patch protein 1 (app1) modestly reduced bmv genomic plus-str ... | 2007 | 17360619 |
| characterization of virus-induced gene silencing in tobacco plants infected with apple latent spherical virus. | apple latent spherical virus (alsv) expressing green fluorescent protein (gfp-alsv) was used for analysis of virus-induced gene silencing (vigs) in tobacco plants expressing gfp (gfp-tobacco). in gfp-tobacco inoculated with gfp-alsv, small dark spots appeared on inoculated leaves at 5 days post-inoculation (dpi), then expanded, and finally covered the whole area of the leaves after 12 dpi. most of the fluorescence of upper leaves above the 12th true leaf disappeared at 21 dpi. thus, gfp-alsv inf ... | 2007 | 17598069 |
| stability of recombinant plant viruses containing genes of unrelated plant viruses. | the stability of hybrid plant viruses that might arise by recombination in transgenic plants was examined using hybrid viruses derived from the viral expression vectors potato virus x (pvx) and tobacco rattle virus (trv). the potato virus y (pvy) nib and hcpro open reading frames (orfs) were introduced into pvx to generate pvx-nib and pvx-hcpro, while the pvy nib orf was introduced into a vector derived from trv rna2 to generate trv-nib. all three viruses were unstable and most of the progeny vi ... | 2007 | 17374781 |
| genetic structure and population variability of tomato yellow leaf curl china virus. | geminiviruses have circular single-stranded dna genomes and are important pathogens in tropical and subtropical regions, but their population diversity and variability are poorly understood. here, we have investigated variations accumulating in tomato yellow leaf curl china virus (tylccnv), a geminivirus in the genus begomovirus of the family geminiviridae. the population variation was analyzed in a naturally infected tomato (solanum lycopersicom) plant and in nicotiana benthamiana and tomato pl ... | 2007 | 17376922 |
| al1-dependent repression of transcription enhances expression of tomato golden mosaic virus al2 and al3. | studies using nicotiana benthamiana protoplasts have determined that repression of upstream transcription by al1 protein enhances al2 and al3 expression in tomato golden mosaic virus (tgmv). mutations resulting in the inability of tgmv al1 protein to associate with its cognate binding site, result in a decrease in both al2 and al3 expression. reduced expression correlates with an increase in transcription from the al62 start site, and decreased transcription from downstream initiation sites (al1 ... | 2007 | 17407785 |
| the consensus n-myristoylation motif of a geminivirus ac4 protein is required for membrane binding and pathogenicity. | some geminiviruses encode a small protein, ac4, whose role in pathogenesis has only recently attracted attention. a few studies have shown that this protein is involved in pathogenesis and suppresses rna silencing. here, using nicotiana benthamiana, we show that east african cassava mosaic cameroon virus (eacmcv) ac4 is a pathogenicity determinant and that it suppresses the systemic phase of rna silencing. furthermore, confocal imaging analyses show that it binds preferentially to the plasma mem ... | 2007 | 17427808 |
| synergistic pathogenicity of a phloem-limited begomovirus and tobamoviruses, despite negative interference. | in contrast to previous observations on phloem-limited geminiviruses supported in movement andaccumulation by rna viruses such as cucumo- and tobamoviruses, tissue infiltration by abutilon mosaic virus (abmv) was enhanced by neither tobacco mosaic virus nor tomato mosaic virus (tomv) in two different hosts, nicotiana benthamiana and tomato. both tobamoviruses exerted a negative effect on the dna virus, resulting in a decrease in abmv accumulation and significantly reduced infectivity in n. benth ... | 2007 | 17325378 |
| a polygalacturonase-inhibiting protein from grapevine reduces the symptoms of the endopolygalacturonase bcpg2 from botrytis cinerea in nicotiana benthamiana leaves without any evidence for in vitro interaction. | six endopolygalacturonases from botrytis cinerea (bcpg1 to bcpg6) as well as mutated forms of bcpg1 and bcpg2 were expressed transiently in leaves of nicotiana benthamiana using agroinfiltration. expression of bcpg1, bcpg2, bcpg4, bcpg5, and mutant bcpg1-d203a caused symptoms, whereas bcpg3, bcpg6, and mutant bcpg2-d192a caused no symptoms. expression of bcpg2 caused the most severe symptoms, including wilting and necrosis. bcpg2 previously has been shown to be essential for b. cinerea virulence ... | 2007 | 17427809 |
| the mi-1-mediated pest resistance requires hsp90 and sgt1. | the tomato (solanum lycopersicum) mi-1 gene encodes a protein with putative coiled-coil nucleotide-binding site and leucine-rich repeat motifs. mi-1 confers resistance to root-knot nematodes (meloidogyne spp.), potato aphids (macrosiphum euphorbiae), and sweet potato whitefly (bemisia tabaci). to identify genes required in the mi-1-mediated resistance to nematodes and aphids, we used tobacco rattle virus (trv)-based virus-induced gene silencing (vigs) to repress candidate genes and assay for nem ... | 2007 | 17351050 |
| molecular and pathotypic characterization of new xanthomonas oryzae strains from west africa. | dna polymorphism analysis and pathogenicity assays were used to characterize strains of xanthomonas oryzae pv. oryzae and xanthomonas oryzae pv. oryzicola collected from rice leaves in west africa. restriction fragment length polymorphism (rflp), repetitive sequence-based polymerase chain reaction, fluorescent amplified fragment-length polymorphism (faflp) analyses were assessed for molecular characterization, while pathogenicity was tested by leaf clipping and leaf infiltration. dendrograms wer ... | 2007 | 17506331 |
| microscopic and transcriptome analyses of early colonization of tomato roots by trichoderma harzianum. | the capacity of the fungus trichoderma harzianum cect 2413 to colonize roots and stimulate plant growth was analyzed. tobacco seedlings (nicotiana benthamiana) transferred to petri dishes inoculated with t. harzianum conidia showed increased plant fresh weight (140%) and foliar area (300%), as well as the proliferation of secondary roots (300%) and true leaves (140%). the interaction between strain cect 2413 and the tomato-root system was also studied during the early stages of root colonization ... | 2007 | 17407057 |
| rna4-encoded p31 of beet necrotic yellow vein virus is involved in efficient vector transmission, symptom severity and silencing suppression in roots. | rna3 and rna4 of beet necrotic yellow vein virus (bnyvv) are not essential for virus multiplication, but are associated with vector-mediated infection and disease development in sugar beet roots. here, a unique role for rna4 in virus transmission, virulence and rna silencing suppression was demonstrated. mutagenic analysis revealed that the rna4-encoded p31 open reading frame (orf) was involved in efficient vector transmission and slight enhancement of symptom expression in some beta species. no ... | 2007 | 17412994 |
| [the c4 proteins of ageratum yellow vein china virus and stachytarpheta leaf curl virus are suppressors of rna silencing]. | rna silencing is a highly conserved mechanism in many eukaryotic organisms that involves sequence-specific rna degradation. one of the important roles of rna silencing is antiviral infection. to counter this defense mechanism, many plant viruses have evolved or acquired functional proteins (suppressors) for suppression of rna silencing. geminiviruses are a family of small circular single-stranded dna (ssdna) viruses that cause severe diseases in major crop plants worldwide. ac2 (c2) and ac4 (c4) ... | 2007 | 17436621 |
| high-frequency reversion of geminivirus replication protein mutants during infection. | the geminivirus replication protein al1 interacts with retinoblastoma-related protein (rbr), a key regulator of the plant division cell cycle, to induce conditions permissive for viral dna replication. previous studies of tomato golden mosaic virus (tgmv) al1 showed that amino acid l148 in the conserved helix 4 motif is critical for rbr binding. in this work, we examined the effect of an l148v mutation on tgmv replication in tobacco cells and during infection of nicotiana benthamiana plants. the ... | 2007 | 17670823 |
| virus-induced gene silencing of 14-3-3 genes abrogates dark repression of nitrate reductase activity in nicotiana benthamiana. | in order to study the effect of repression of 14-3-3 genes on actual activity of the nitrate reductase (nr) in nicotiana benthamiana leaves, nb14-3-3a gene was silenced by virus-induced gene silencing (vigs) method using potato virus x (pvx). expression of nb14-3-3a as well as nb14-3-3b genes was altogether repressed in the leaves of pvx-14-3a-infected plants. furthermore, two-dimensional gel electrophoresis and immunoblot analysis with anti-14-3-3 antiserum suggested that the expressions of nb1 ... | 2007 | 17443349 |
| 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 tom1 homologue is required for multiplication of tobacco mosaic virus in nicotiana benthamiana. | the attom1 gene of arabidopsis thaliana had been shown to be essential for the efficient multiplication of tobacco mosaic virus (tmv) in a. thaliana. in this study, we cloned an attom1-like gene from nicotiana benthamiana named as nbtom1. sequence alignment showed that nbtom1 is closely related to attom1 homologues of n. tabacum and lycopersicon esculentum with 97.2% and 92.6% nucleotide sequence identities, respectively. silencing of nbtom1 by a modified viral satellite dna-based vector resulte ... | 2007 | 17444600 |
| abutilon mosaic virus dna b component supports mechanical virus transmission, but does not counteract begomoviral phloem limitation in transgenic plants. | different nicotiana benthamiana lines stably transformed with abutilon mosaic virus (abmv) dimeric dna b were capable of systemically spreading complete bipartite abmv genomes, following agroinoculation of dna a alone. constitutively expressed viral movement protein (bc1) did not induce any persistent disease phenotype, but plants developed transient morphological abnormalities such as radially symmetric leaves after kanamycin withdrawal. systemic abmv infection produced symptoms and virus titer ... | 2007 | 17462695 |
| plant-derived human acetylcholinesterase-r provides protection from lethal organophosphate poisoning and its chronic aftermath. | therapeutically valuable proteins are often rare and/or unstable in their natural context, calling for production solutions in heterologous systems. a relevant example is that of the stress-induced, normally rare, and naturally unstable "read-through" human acetylcholinesterase variant, ache-r. ache-r shares its active site with the synaptic ache-s variant, which is the target of poisonous organophosphate anticholinesterase insecticides such as the parathion metabolite paraoxon. inherent ache-r ... | 2007 | 17475919 |
| expression of animal ced-9 anti-apoptotic gene in tobacco modifies plasma membrane ion fluxes in response to salinity and oxidative stress. | apoptosis, one form of programmed cell death (pcd), plays an important role in mediating plant adaptive responses to the environment. recent studies suggest that expression of animal anti-apoptotic genes in transgenic plants may significantly improve a plant's ability to tolerate a variety of biotic and abiotic stresses. the underlying cellular mechanisms of this process remain unexplored. in this study, we investigated specific ion flux "signatures" in nicotiana benthamiana plants transiently e ... | 2007 | 17712568 |
| the nucleoprotein of tomato spotted wilt virus as protein tag for easy purification and enhanced production of recombinant proteins in plants. | upon infection, tomato spotted wilt virus (tswv) forms ribonucleoprotein particles (rnps) that consist of nucleoprotein (n) and viral rna. these aggregates result from the homopolymerization of the n protein, and are highly stable in plant cells. these properties feature the n protein as a potentially useful protein fusion partner. to evaluate this potential, the n protein was fused to the aequorea victoria green fluorescent protein (gfp), either at the amino or carboxy terminus, and expressed i ... | 2007 | 17532227 |
| comparative expression profiling of nicotiana benthamiana leaves systemically infected with three fruit tree viruses. | plant viruses cause a wide array of disease symptoms and cytopathic effects. although some of these changes are virus specific, many appear to be common even among diverse viruses. currently, little is known about the underlying molecular determinants. to identify gene expression changes that are concomitant with virus symptoms, we performed comparative expression profiling experiments on nicotiana benthamiana leaves infected with one of three different fruit tree viruses that produce distinct s ... | 2007 | 17722703 |
| plant signalling components eds1 and sgt1 enhance disease caused by the necrotrophic pathogen botrytis cinerea. | * botrytis cinerea is a necrotrophic fungus that causes grey mould on a wide range of food plants, especially grapevine, tomato, soft fruits and vegetables. this disease brings about important economic losses in both pre- and postharvest crops. successful protection of host plants against this pathogen is severely hampered by a lack of resistance genes in the hosts and the considerable phenotypic diversity of the fungus. * the aim of this study was to test whether b. cinerea manipulates the immu ... | 2007 | 17547673 |
| expression of a metacaspase gene of nicotiana benthamiana after inoculation with colletotrichum destructivum or pseudomonas syringae pv. tomato, and the effect of silencing the gene on the host response. | metacaspases are cysteine proteinases that have homology to caspases, which play a central role in signaling and executing programmed cell death in animals. a type ii metacaspase cdna, nbmca1, was amplified from nicotiana benthamiana infected with colletotrichum destructivum. it showed a peak in expression at 72 h post-inoculation corresponding with the switch to necrotrophy by c. destructivum. inoculation of n. benthamiana with an incompatible bacterium, pseudomonas syringae pv. tomato, which s ... | 2007 | 17576564 |
| ap2-erf transcription factors mediate nod factor dependent mt enod11 activation in root hairs via a novel cis-regulatory motif. | rhizobium nod factors (nfs) are specific lipochitooligosaccharides that activate host legume signaling pathways essential for initiating the nitrogen-fixing symbiotic association. this study describes the characterization of cis-regulatory elements and trans-interacting factors that regulate nf-dependent and epidermis-specific gene transcription in medicago truncatula. detailed analysis of the mt enod11 promoter using deletion, mutation, and gain-of-function constructs has led to the identificat ... | 2007 | 17827349 |
| a chimeric plum pox virus shows reduced spread and cannot compete with its parental wild-type viruses in a mixed infection. | the effect of a recombination event in the genomic 3' end on the biological properties and competitiveness of plum pox virus (ppv) was investigated. therefore, a fragment spanning the coat protein (cp) coding region and a part of the 3' non-translated region of a non-aphid-transmissible strain of ppv (ppv-nat) was replaced by the corresponding region of a ppv sour cherry isolate (ppv-soc). the resulting chimera (ppv-nat/soc) caused severe symptoms in nicotiana benthamiana, resembling those of pp ... | 2007 | 17872539 |
| the syntaxin syp132 contributes to plant resistance against bacteria and secretion of pathogenesis-related protein 1. | in contrast to many mammalian pathogens, potential bacterial pathogens of plants remain outside the host cell. the plant must, therefore, promote an active resistance mechanism to combat the extracellular infection. how this resistance against bacteria is manifested and whether similar processes mediate basal, gene-for-gene, and salicylate-associated defense, however, are poorly understood. here, we identify a specific plasma membrane syntaxin, nbsyp132, as a component contributing to gene-for-g ... | 2007 | 17592123 |
| psite vectors for stable integration or transient expression of autofluorescent protein fusions in plants: probing nicotiana benthamiana-virus interactions. | plant functional proteomics research is increasingly dependent upon vectors that facilitate high-throughput gene cloning and expression of fusions to autofluorescent proteins. here, we describe the psite family of plasmids, a new set of agrobacterium binary vectors, suitable for the stable integration or transient expression of various autofluorescent protein fusions in plant cells. the psite vectors permit single-step gateway-mediated recombination cloning for construction of binary vectors tha ... | 2007 | 17601162 |
| virp1 is a host protein with a major role in potato spindle tuber viroid infection in nicotiana plants. | viroids are small, circular, single-stranded rna molecules that, while not coding for any protein, cause several plant diseases. viroids rely for their infectious cycle on host proteins, most of which are likely to be involved in endogenous rna-mediated phenomena. therefore, characterization of host factors interacting with the viroid may contribute to the elucidation of rna-related pathways of the hosts. potato spindle tuber viroid (pstvd) infects several members of the solanaceae family. in an ... | 2007 | 17898061 |
| characterization of a novel toll/interleukin-1 receptor (tir)-tir gene differentially expressed in common bean (phaseolus vulgaris cv. othello) undergoing a defence response to the geminivirus bean dwarf mosaic virus. | summary common bean (phaseolus vulgaris l.) cultivar (cv.) othello develops a hypersensitive response-associated vascular resistance to infection by bean dwarf mosaic virus (bdmv), a single-stranded dna virus (genus begomovirus, family geminiviridae). a pcr-based cdna subtraction approach was used to identify genes involved in this resistance response. eighteen clones, potentially involved with bdmv resistance, were identified based upon being up-regulated in bdmv-infected tissues and/or having ... | 2007 | 20507487 |
| structural and functional characterization of a novel, host penetration-related pectate lyase from the potato cyst nematode globodera rostochiensis. | summary the cell wall, a strong extraprotoplasmic layer surrounding plant cells that mainly consists of a variety of polysaccharides, constitutes a major barrier for potential parasites. plant-parasitic nematodes are well equipped to overcome this barrier as they produce and secrete cell-wall-degrading enzymes. expression profiling of various life stages of the potato cyst nematode globodera rostochiensis revealed a novel pectate lyase gene (gr-pel2, 759 bp). the gr-pel2 protein showed highest s ... | 2007 | 20507500 |
| functional analysis of nlp genes from botrytis elliptica. | summary we functionally analysed two nep1-like protein (nlp) genes from botrytis elliptica (a specialized pathogen of lily), encoding proteins homologous to the necrosis and ethylene-inducing protein (nep1) from fusarium oxysporum. single gene replacement mutants were made for benep1 and benep2, providing the first example of transformation and successful targeted mutagenesis in this fungus. the virulence of both mutants on lily leaves was not affected. benep1 and benep2 were individually expres ... | 2007 | 20507492 |
| zucchini yellow mosaic virus: insect transmission and pathogenicity -the tails of two proteins. | summary taxonomy: zucchini yellow mosaic virus (zymv) is a member of genus potyvirus, family potyviridae. zymv is a positive-strand rna virus. physical properties: virions are flexuous filaments of 680-730 nm in length and 11-13 nm in diameter, composed of about 2000 subunits of a single 31-kda protein (calculated). the genome rna size is 9.6 kb covalently linked to a viral-encoded protein (the vpg) at the 5' end, and with a 3' poly a tail. the 5' end of the sequence is au-rich (69%). viral prot ... | 2007 | 20507486 |
| suppression of cdc27b expression induces plant defence responses. | summary: non-host resistance is the most general form of disease resistance in plants because it is effective against most phytopathogens. the importance of hypersensitive responses (hrs) in non-host resistance of nicotiana species to the oomycete phytophthora is clear. inf1 elicitin, an elicitor obtained from the late-blight pathogen phytophthora infestans, is sufficient to induce a typical hr in nicotiana species. the molecular mechanisms that underlie the non-host resistance component of plan ... | 2007 | 20507506 |
| dspa/e, a type iii effector of erwinia amylovora, is required for early rapid growth in nicotiana benthamiana and causes nbsgt1-dependent cell death. | summary dspa/e is a pathogenicity factor of erwinia amylovora that is translocated into the plant cell cytoplasm through an hrp type iii secretion system. transient expression of dspa/e in nicotiana benthamiana or yeast induced cell death, as it does in n. tabacum and apple as described previously. dspa/e-induced cell death in n. benthamiana was not inhibited by coexpression of avrptob of pseudomonas syringae pv. tomato, which inhibits programmed cell death (pcd) induced by several other elicito ... | 2007 | 20507497 |
| the receptor-like kinase serk3/bak1 is a central regulator of innate immunity in plants. | in pathogen-associated molecular pattern (pamp)-triggered immunity (pti), plant cell surface receptors sense potential microbial pathogens by recognizing elicitors called pamps. although diverse pamps trigger pti through distinct receptors, the resulting intracellular responses overlap extensively. despite this, a common component(s) linking signal perception with transduction remains unknown. in this study, we identify somatic embryogenesis receptor kinase (serk)3/brassinosteroid-associated kin ... | 2007 | 17626179 |
| calcium-dependent protein kinases regulate the production of reactive oxygen species by potato nadph oxidase. | reactive oxygen species (ros) are implicated in plant innate immunity. nadph oxidase (rboh; for respiratory burst oxidase homolog) plays a central role in the oxidative burst, and ef-hand motifs in the n terminus of this protein suggest possible regulation by ca(2+). however, regulatory mechanisms are largely unknown. we identified ser-82 and ser-97 in the n terminus of potato (solanum tuberosum) st rbohb as potential phosphorylation sites. an anti-phosphopeptide antibody (pser82) indicated that ... | 2007 | 17400895 |
| characterization of a u.s. isolate of beet black scorch virus. | abstract the first reported u.s. isolate of beet black scorch necrovirus (bbsv) was obtained and characterized. host range of the virus for localized and occasionally systemic infection included the chenopodiaceae and tetragonia expansa; nicotiana benthamiana supported symptomless systemic infection by the virus. the complete nucleotide sequence of the genomic rna of the virus, designated bbsv-co, exhibits 93% similarity to the genome of the 'ningxia' isolate of bbsv from china. amino acid seque ... | 2007 | 18943682 |
| molecular and biological characterization of tomato chlorotic mottle virus suggests that recombination underlies the evolution and diversity of brazilian tomato begomoviruses. | abstract tomato chlorotic mottle virus (tocmov) is an emerging begomovirus species widely distributed throughout tomato-growing regions of brazil. tocmov appears to have expanded its geographic range recently, invading tomato-growing areas that were free of begomovirus infection before 2004. we have determined the first complete genome sequence of an infectious tocmov genome (isolate ba-se1), which is the first begomovirus species isolated in the northeast of brazil. when introduced by particle ... | 2007 | 18943601 |
| analysis of the spatial distribution of identical and two distinct virus populations differently labeled with cyan and yellow fluorescent proteins in coinfected plants. | abstract apple latent spherical virus (alsv) expressing yellow and cyan fluorescent proteins (alsv-yfp and alsv-cfp) was used to investigate the distribution of identical virus populations in coinfected plants. in chenopodium quinoa plants inoculated with a mixture of alsv-yfp and alsv-cfp, fluorescence from yfp and cfp was always distributed separately in both inoculated and upper uninoculated leaves. inoculation of each alsv-yfp and alsv-cfp to different leaves of a c. quinoa plant resulted in ... | 2007 | 18943677 |
| regulation of rice nadph oxidase by binding of rac gtpase to its n-terminal extension. | reactive oxygen species (ros) produced by nadph oxidase play critical roles in various cellular activities, including plant innate immunity response. in contrast with the large multiprotein nadph oxidase complex of phagocytes, in plants, only the homologs of the catalytic subunit gp91phox and the cytosolic regulator small gtpase rac are found. plant homologs of the gp91phox subunit are known as rboh (for respiratory burst oxidase homolog). although numerous rboh have been isolated in plants, the ... | 2007 | 18156215 |
| high-level transient production of a heterologous protein in plants by optimizing induction of a chemically inducible viral amplicon expression system. | we have demonstrated that the method of chemical induction using a chemically inducible viral amplicon expression system can be optimized to increase expression of a heterologous protein in plants. a cucumber mosaic virus inducible viral amplicon (cmviva) expression system was used to transiently produce a recombinant human blood protein, alpha-1-antitrypsin (aat), by co-infiltrating intact and detached nicotiana benthamiana leaves with two agrobacterium tumefaciens strains, one containing the c ... | 2007 | 17994759 |
| assessing the expression of chicken anemia virus proteins in plants. | chicken anemia virus (cav) is an important pathogen of chicken worldwide, causing severe anemia and immunodeficiency. its small single-stranded dna genome (2.3kb) encodes three proteins: vp1, the only structural protein, vp2, a protein phosphatase, and vp3, also known as apoptin, which induces apoptosis. in this study, cav proteins were expressed in plants as an alternative for recombinant protein production in animal cells. additionally, the effect of vp3 expression was tested to evaluate possi ... | 2007 | 17698236 |
| recovery of nicotiana benthamiana plants from a necrotic response induced by a nepovirus is associated with rna silencing but not with reduced virus titer. | recovery of plants from virus-induced symptoms is often described as a consequence of rna silencing, an antiviral defense mechanism. for example, recovery of nicotiana clevelandii from a nepovirus (tomato black ring virus) is associated with a decreased viral rna concentration and sequence-specific resistance to further virus infection. in this study, we have characterized the interaction of another nepovirus, tomato ringspot virus (torsv), with host defense responses during symptom induction an ... | 2007 | 17728227 |
| pseudomonas syringae type iii effector avrptob is phosphorylated in plant cells on serine 258, promoting its virulence activity. | the pseudomonas syringae pv. tomato protein avrptob is translocated into plant cells via the bacterial type iii secretion system. in resistant tomato leaves, avrptob acts as an avirulence protein by interacting with the host pto kinase and eliciting the host immune response. pto-mediated immunity requires prf, a pto-interacting protein with a putative nucleotide-binding site and a region of leucine-rich repeats. in susceptible tomato plants, which lack either pto or prf, avrptob acts as a virule ... | 2007 | 17711844 |
| infection, propagation, distribution and stability of plant virus in hairy root cultures. | nicotiana benthamiana hairy root cultures were infected with tobacco mosaic virus (tmv) and used for in vitro plant virus propagation. the roots were infected with tmv by addition of virus to the medium at the same time as root inoculation. viral accumulation in the biomass was 7-11-fold greater when the initial infection was carried out in b5 medium rather than sodium phosphate buffer; virus accumulation also increased with increasing viral inoculum concentration. the amount of tmv accumulated ... | 2007 | 17767969 |
| a cucumber mosaic virus mutant lacking the 2b counter-defence protein gene provides protection against wild-type strains. | several plant virus mutants, in which genes encoding silencing suppressor proteins have been deleted, are known to induce systemic or localized rna silencing against themselves and other rna molecules containing homologous sequences. thus, it is thought that many cases of cross-protection, in which infection with a mild or asymptomatic virus mutant protects plants against challenge infection with closely related virulent viruses, can be explained by rna silencing. we found that a cucumber mosaic ... | 2007 | 17872541 |
| the chimeric cyclic nucleotide-gated ion channel atcngc11/12 constitutively induces programmed cell death in a ca2+ dependent manner. | the hypersensitive response (hr) involves programmed cell death (pcd) in response to pathogen infection. to investigate the pathogen resistance signaling pathway, we previously identified the arabidopsis mutant cpr22, which displays constitutive activation of multiple defense responses including hr like cell death. the cpr22 mutation has been identified as a 3 kb deletion that fuses two cyclic nucleotide-gated ion channel (cngc)-encoding genes, atcngc11 and atcngc12, to generate a novel chimeric ... | 2007 | 17885810 |
| a novel nuclear protein interacts with the symbiotic dmi3 calcium- and calmodulin-dependent protein kinase of medicago truncatula. | many higher plants establish symbiotic relationships with arbuscular mycorrhizal (am) fungi that improve their ability to acquire nutrients from the soil. in addition to establishing am symbiosis, legumes also enter into a nitrogen-fixing symbiosis with bacteria known as rhizobia that results in the formation of root nodules. several genes involved in the perception and transduction of bacterial symbiotic signals named "nod factors" have been cloned recently in model legumes through forward gene ... | 2007 | 17722695 |
| a ligation-independent cloning tobacco rattle virus vector for high-throughput virus-induced gene silencing identifies roles for nbmads4-1 and -2 in floral development. | virus-induced gene silencing (vigs) is a widely used, powerful technique for reverse genetics. vigs vectors derived from the tobacco rattle virus (trv) are among the most popular for vigs. we have developed a trv rna2 vector that allows the insertion of gene silencing fragments by ligation-independent cloning (lic). this new vector has several advantages over previous vectors, particularly for applications involving the analysis of large numbers of sequences, since trv-lic vectors containing the ... | 2007 | 17932306 |
| genomic resources for myzus persicae: est sequencing, snp identification, and microarray design. | the green peach aphid, myzus persicae (sulzer), is a world-wide insect pest capable of infesting more than 40 plant families, including many crop species. however, despite the significant damage inflicted by m. persicae in agricultural systems through direct feeding damage and by its ability to transmit plant viruses, limited genomic information is available for this species. | 2007 | 18021414 |
| a systematic study to determine the extent of gene silencing in nicotiana benthamiana and other solanaceae species when heterologous gene sequences are used for virus-induced gene silencing. | virus-induced gene silencing (vigs) is a rapid and robust method for determining and studying the function of plant genes or expressed sequence tags (ests). however, only a few plant species are amenable to vigs. there is a need for a systematic study to identify vigs-efficient plant species and to determine the extent of homology required between the heterologous genes and their endogenous orthologs for silencing. two approaches were used. first, the extent of phytoene desaturase (pds) gene sil ... | 2007 | 17997764 |
| the arabidopsis vacuolar malate channel is a member of the almt family. | in plants, malate is a central metabolite and fulfills a large number of functions. vacuolar malate may reach very high concentrations and fluctuate rapidly, whereas cytosolic malate is kept at a constant level allowing optimal metabolism. recently, a vacuolar malate transporter (arabidopsis thaliana tonoplast dicarboxylate transporter, attdt) was identified that did not correspond to the well-characterized vacuolar malate channel. we therefore hypothesized that a member of the aluminum-activate ... | 2007 | 18005230 |
| antagonistic control of powdery mildew host cell entry by barley calcium-dependent protein kinases (cdpks). | calcium-dependent protein kinases (cdpks) are known to play pivotal roles in intracellular signaling during abiotic and biotic stress responses. to unravel potential functions of cdpks in the course of barley (hordeum vulgare)-powdery mildew (blumeria graminis) interactions, we systematically analyzed the hvcdpk gene family. we found that, according to the existence of respective expressed sequence tags, at least nine paralogs are expressed in the barley leaf epidermis, the sole target tissue of ... | 2007 | 17918623 |
| new type iii effectors from xanthomonas campestris pv. vesicatoria trigger plant reactions dependent on a conserved n-myristoylation motif. | pathogenicity of the gram-negative plant pathogen xanthomonas campestris pv. vesicatoria depends on a type iii secretion system, which translocates bacterial effector proteins into the plant cell. in this study, we identified two novel type iii effectors, xope1 and xope2 (xanthomonas outer proteins), using the avrbs3 effector domain as reporter. xope1 and xope2 belong to the hopx family and possess a conserved putative n-myristoylation motif that is also present in the effector xopj from x. camp ... | 2007 | 17918627 |
| downregulation of the nbnaca1 gene encoding a movement-protein-interacting protein reduces cell-to-cell movement of brome mosaic virus in nicotiana benthamiana. | the 3a movement protein (mp) plays a central role in the movement of the rna plant virus, brome mosaic virus (bmv). to identify host factor genes involved in viral movement, a cdna library of nicotiana benthamiana, a systemic host for bmv, was screened with far-western blotting using a recombinant bmv mp as probe. one positive clone encoded a protein with sequence similarity to the alpha chain of nascent-polypeptide-associated complex from various organisms, which is proposed to contribute to th ... | 2007 | 17555275 |
| genetic and molecular requirements for function of the pto/prf effector recognition complex in tomato and nicotiana benthamiana. | the pto gene of tomato (solanum lycopersicum) confers specific recognition of the unrelated bacterial effector proteins avrpto and avrptob. pto resides in a constitutive molecular complex with the nucleotide binding site-leucine rich repeats protein prf. prf is absolutely required for specific recognition of both effectors. here, using stable transgenic lines, we show that expression of pto from its genomic promoter in susceptible tomatoes was sufficient to complement recognition of pseudomonas ... | 2007 | 17635766 |
| potyvirus-induced gene silencing: the dynamic process of systemic silencing and silencing suppression. | potato virus a (pva; genus potyvirus) was used for virus-induced gene silencing in a model system that included transgenic nicotiana benthamiana (line 16c) expressing the gfp transgene for green fluorescent protein (gfp) and chimeric pva (pva-gfp) carrying gfp in the p1-encoding region. infection of the 16c plants with pva-gfp in five experiments resulted in a reproducible pattern of systemic gfp transgene silencing, despite the presence of the strong silencing-suppressor protein, hc-pro, produc ... | 2007 | 17622640 |
| a rangap protein physically interacts with the nb-lrr protein rx, and is required for rx-mediated viral resistance. | race-specific disease resistance in plants is mediated by the products of host disease resistance (r) genes. plant genomes possess hundreds of r gene homologs encoding nucleotide-binding and leucine-rich repeat (nb-lrr) proteins. nb-lrr proteins induce a disease resistance response following recognition of pathogen-encoded avirulence (avr) proteins. however, little is known about the general mechanisms by which nb-lrr proteins recognize avr proteins or how they subsequently induce defense respon ... | 2007 | 17655649 |
| alternative splicing and mrna levels of the disease resistance gene rps4 are induced during defense responses. | the arabidopsis (arabidopsis thaliana) disease resistance protein resistance to pseudomonas syringae4 (rps4) activates defenses in response to bacterial pathogens expressing avrrps4 in a gene-for-gene specific manner. the rps4 gene produces multiple transcripts via alternative splicing of two regular introns flanking exon 3 and a cryptic intron within exon 3. we showed previously that rps4-mediated resistance requires the combined presence of transcripts encoding both full-length and truncated o ... | 2007 | 17951452 |
| induction of a small heat shock protein and its functional roles in nicotiana plants in the defense response against ralstonia solanacearum. | in tobacco (nicotiana tabacum), ralstonia solanacearum oe1-1 (rsoe1-1) is pathogenic, whereas r. solanacearum 8107 (rs8107) is nonpathogenic and induces the hypersensitive response (hr). to elucidate the molecular mechanisms of plant-r. solanacearum interactions, we used differential display to isolate a cdna fragment, a6, regulated in tobacco by inoculation with rsoe1-1. the deduced amino acid sequence predicted from full-length a6-cdna showed similarity to small heat shock proteins from arabid ... | 2007 | 17965181 |
| expression of the arabidopsis xrn4p 5'-3' exoribonuclease facilitates degradation of tombusvirus rna and promotes rapid emergence of viral variants in plants. | rapid rna virus evolution is a major problem due to the devastating diseases caused by human, animal and plant-pathogenic rna viruses. a previous genome-wide screen for host factors affecting recombination in tomato bushy stunt tombusvirus (tbsv), a small monopartite plant virus, identified xrn1p 5'-3' exoribonuclease of yeast, a model host, whose absence led to increased appearance of recombinants [serviene, e., shapka, n., cheng, c.p., panavas, t., phuangrat, b., baker, j., nagy, p.d., (2005). ... | 2007 | 17688902 |
| adaptation of the "in-gel release method" to n-glycome analysis of low-milligram amounts of material. | protein n-glycosylation is a post-translational modification which plays numerous crucial physiological roles. the n-glycan pattern varies depending on the species organs, tissues and even cell types and their respective physiological states. obtaining enough starting material from a particular cell type or tissue for n-glycan purification by conventional methods can, in certain cases, be very difficult. previously, a sensitive technique, the "in-gel release method" that allows the determination ... | 2007 | 18041037 |
| interaction between sgt1 and cytosolic/nuclear hsc70 chaperones regulates arabidopsis immune responses. | the conserved eukaryotic protein sgt1 (for suppressor of g2 allele of skp1) has characteristics of an hsp90 (for heat shock protein 90 kd) cochaperone and in plants regulates hormone responses and resistance gene-triggered immunity. we affinity-purified sgt1-interacting proteins from arabidopsis thaliana leaf extracts and identified by mass spectrometry cytosolic heat shock cognate 70 (hsc70) chaperones as the major stable sgt1 interactors. arabidopsis sgt1a and sgt1b proteins associate with hsc ... | 2007 | 18065690 |
| the activity and isoforms of nadp-malic enzyme in nicotiana benthamiana plants under biotic stress. | the activity and presence of isoforms of nadp-dependent malic enzyme (nadp-me, ec 1.1.1.40) were studied in non-transgenic and transgenic nicotiana benthamiana plants containing potyviral gene for helper component protease (hc-pro) and in plants infected by potato virus y strain ntn (pvy(ntn)). no significant changes in enzyme activities and isoenzyme pattern were observed due to foreign gene introduction and pvy(ntn) infection. however, the activity and isoenzyme composition of nadp-me measured ... | 2007 | 18281746 |
| biological activity of transcripts from cdna of pelargonium line pattern virus. | a set of cdnas of pelargonium line pattern virus (plpv) was assembled under the control of t7 rna polymerase promoter and ligated into the plasmid puc18. transcripts synthesized in vitro from cdna were infectious on chenopodium quinoa according to locally induced lesions and hybridization assay. the biological activity of the viral transcripts was particularly sensitive to the short 3' terminus extensions, whereas inclusion of the 3 extra bases at the 5' terminus did not substantially affect the ... | 2007 | 18197735 |
| 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 |
| hlmyb3, a putative regulatory factor in hop (humulus lupulus l.), shows diverse biological effects in heterologous transgenotes. | a hop-specific cdna library from glandular tissue-enriched hop cones was screened for myb transcription factors. cdna encoding for r2r3 myb, designated hlmyb3, was cloned and characterized. according to the amino acid (aa) sequence, hlmyb3 shows the highest homology to ghmyb5 from cotton and is unrelated to the previously characterized hlmyb1 from the hop. southern blot analyses indicated that hlmyb3 is a unique gene, which was detected in various humulus lupulus cultivars, but not in humulus ja ... | 2007 | 17708645 |
| functional analysis of the naturally recombinant dna-a of the bipartite begomovirus tomato chlorotic mottle virus. | all geminiviruses found in brazil belong to the begomovirus genus with a bipartite genome that is split between two genomic components, dna-a and dna-b. the dna-a of the bipartite begomovirus tocmov-[mg-bt] (tomato chlorotic mottle virus), however, possesses as a peculiar characteristic the capacity to systemically infect nicotiana benthamiana. here we further characterize this variant dna-a and show that it also infects solanum lycopersicum and other host plants, in the absence of dna-b. the to ... | 2007 | 17367887 |
| the senescence-induced staygreen protein regulates chlorophyll degradation. | loss of green color in leaves results from chlorophyll (chl) degradation in chloroplasts, but little is known about how chl catabolism is regulated throughout leaf development. using the staygreen (sgr) mutant in rice (oryza sativa), which maintains greenness during leaf senescence, we identified sgr, a senescence-associated gene encoding a novel chloroplast protein. transgenic rice overexpressing sgr produces yellowish-brown leaves, and arabidopsis thaliana pheophorbide a oxygenase-impaired mut ... | 2007 | 17513504 |
| ageratum yellow vein china virus is a distinct begomovirus species associated with a dnabeta molecule. | abstract ageratum conyzoides plants exhibiting yellow vein symptoms, collected near haikou, hainan province, china, contained begomoviral dna-a-like molecules. the complete sequences of the molecules from two samples, hn2 and hn2-19, were shown to consist of 2,768 and 2,748 nucelotides (nt), respectively. these sequences have more than 97% nucleotide sequence identity, but less than 86% identity with other reported begomovirus sequences. in line with the taxonomic convention for begomoviruses, h ... | 2007 | 18943280 |
| a begomovirus associated with ageratum yellow vein disease in indonesia: evidence for natural recombination between tomato leaf curl java virus and ageratum yellow vein virus-[java]. | a begomovirus (2747 nucleotides) and a satellite dna beta component (1360 nucleotides) have been isolated from ageratum conyzoides l. plants with yellow vein symptoms growing in java, indonesia. the begomovirus is most closely related to tomato leaf curl java virus (tolcjv) (91 and 98% in the total nucleotide and coat protein amino acid sequences, respectively), although the products of orfs c1 and c4 are more closely related to those of ageratum yellow vein virus-[java] (91 and 95% identity, re ... | 2007 | 17294343 |
| effector genomics accelerates discovery and functional profiling of potato disease resistance and phytophthora infestans avirulence genes. | potato is the world's fourth largest food crop yet it continues to endure late blight, a devastating disease caused by the irish famine pathogen phytophthora infestans. breeding broad-spectrum disease resistance (r) genes into potato (solanum tuberosum) is the best strategy for genetically managing late blight but current approaches are slow and inefficient. we used a repertoire of effector genes predicted computationally from the p. infestans genome to accelerate the identification, functional ... | 2008 | 18682852 |
| rna-directed rna polymerase3 from nicotiana attenuata is required for competitive growth in natural environments. | sde1/sgs2/rdr6, a putative rna-directed rna polymerase, maintains plant defenses against viruses in arabidopsis (arabidopsis thaliana) and nicotiana benthamiana, but its function has not been examined in natural habitats or with respect to other ecological stresses. we evaluated the organismic-level function of this gene (nardr3) in an ecological model species, nicotiana attenuata, by transforming plants to stably silence rdr3 (irrdr3). minor morphological changes (elongated leaves and reduced l ... | 2008 | 18480375 |
| different subcellular localizations and functions of arabidopsis myosin viii. | myosins are actin-activated atpases that use energy to generate force and move along actin filaments, dragging with their tails different cargos. plant myosins belong to the group of unconventional myosins and arabidopsis myosin viii gene family contains four members: atm1, atm2, myosin viiia and myosin viiib. | 2008 | 18179725 |
| myosin xi-k is required for rapid trafficking of golgi stacks, peroxisomes, and mitochondria in leaf cells of nicotiana benthamiana. | a prominent feature of plant cells is the rapid, incessant movement of the organelles traditionally defined as cytoplasmic streaming and attributed to actomyosin motility. we sequenced six complete nicotiana benthamiana cdnas that encode class xi and class viii myosins. phylogenetic analysis indicates that these two classes of myosins diverged prior to the radiation of green algae and land plants from a common ancestor and that the common ancestor of land plants likely possessed at least seven m ... | 2008 | 18178670 |
| strains of a new bipartite begomovirus, pepper yellow leaf curl indonesia virus, in leaf-curl-diseased tomato and yellow-vein-diseased ageratum in indonesia. | the complete nucleotide sequences of begomoviruses from pepper with leaf curl and yellowing symptoms, tomato with leaf curl symptoms, and ageratum with yellow vein in indonesia were determined. on the basis of genome organization and sequence homology, they were proposed to belong to a new species, pepper yellow leaf curl indonesia virus (pepylciv), which includes the new strains pepylciv-tomato and pepylciv-ageratum. these viruses had bipartite genomes. pepper virus dnas from indonesia (pepylci ... | 2008 | 19015934 |
| assessment of camv-mediated gene silencing and integration of camv into gm plants with a 35s rna promoter. | four gm plant species (arabidopsis thaliana, brassica napus, nicotiana benthamiana and n. tabacum), each expressing the gene encoding the jellyfish green fluorescent protein (gfp) regulated by the cauliflower mosaic virus (camv) 35s rna promoter, were assessed for the extent of transgene silencing and viral genome integration following infection by camv. the first three species are systemic hosts of camv, while n. tabacum is only a local host for a few strains of camv. a generalized systemic sil ... | 2008 | 18289501 |
| role of a gdsl lipase-like protein as sinapine esterase in brassicaceae. | the seeds of most members of the brassicaceae accumulate high amounts of sinapine (sinapoylcholine) that is rapidly hydrolyzed during early stages of seed germination. one of three isoforms of sinapine esterase activity (bnsce3) has been isolated from brassica napus seedlings and subjected to trypsin digestion and spectrometric sequencing. the peptide sequences were used to isolate bnsce3 cdna, which was shown to contain an open reading frame of 1170 bp encoding a protein of 389 amino acids, inc ... | 2008 | 18036206 |
| 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 |
| influenza virus-like particles produced by transient expression in nicotiana benthamiana induce a protective immune response against a lethal viral challenge in mice. | a strain-specific vaccine represents the best possible response to the threat of an influenza pandemic. rapid delivery of such a vaccine to the world's population before the peak of the first infection wave seems to be an unattainable goal with the current influenza vaccine manufacturing capacity. plant-based transient expression is one of the few production systems that can meet the anticipated surge requirement. to assess the capability of plant agroinfiltration to produce an influenza vaccine ... | 2008 | 19076615 |
| investigating recombinant protein exudation from roots of transgenic tobacco. | it is widely acknowledged that plant-made pharmaceuticals (pmps) offer numerous benefits, including inexpensive production, biological safety and the facility for production at agricultural scale. at the same time, it is important to minimize any potential risk associated with this new technology, including the potential release of bioactive proteins into the environment. to address this issue, we studied transgenic nicotiana benthamiana and nicotiana tabacum plants expressing two recombinant si ... | 2008 | 19081009 |
| subcellular localization and in vivo interactions of the arabidopsis thaliana ethylene receptor family members. | the gaseous phytohormone ethylene regulates many developmental processes and responses to environmental conditions in higher plants. in arabidopsis thaliana, ethylene perception and initiation of signaling are mediated by a family of five receptors which are related to prokaryotic two-component sensor histidine kinases. the transient expression of fluorescence-tagged receptors in tobacco (nicotiana benthamiana) epidermal leaf cells demonstrated that all ethylene receptors are targeted to the er ... | 2008 | 19825542 |
| hairy-root organ cultures for the production of human acetylcholinesterase. | human cholinesterases can be used as a bioscavenger of organophosphate toxins used as pesticides and chemical warfare nerve agents. the practicality of this approach depends on the availability of the human enzymes, but because of inherent supply and regulatory constraints, a suitable production system is yet to be identified. | 2008 | 19105816 |
| 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 |
| 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 |