WorldWideScience

Sample records for arabidopsis zar1 resistance

  1. MOLECULAR CLONING AND EXPRESSION PATTERN OF ZAR1 AND ZAR1L IN THE ZEBRAFISH%斑马鱼Zar1Zar1-like基因的克隆及其表达分析

    Institute of Scientific and Technical Information of China (English)

    江文波; 赵冬梅; 胡炜; 赵浩斌

    2011-01-01

    L might have other important roles during embryonic development.%合子阻滞基因1(Zygote arrest 1,Zar1)及Zar1-like(Zar1L)作为母源基因,在小鼠卵子-合子转变过程中发挥着极其重要的作用.研究以斑马鱼为对象,采用cDNA末端快速克隆(RACE)技术获得了Zar1L cDNA全长,并采用RT-PCR技术检测Zar1Zar1L在斑马鱼不同组织器官、卵母细胞和胚胎发育时期的表达情况.Zar1L cDNA的全长为1146 bp,编码311个氨基酸残基,5'非编码区20 bp,3'非编码区190 bp.多重序列比对结果显示,C-末端的序列非常保守,相似性高达74%,具有非典型的PHD基序(Plant homeo domain),并具有两个C4类型的锌指结构.在基因结构上,Zar1Zar1L均南四个外显子构成,两个基因的每一个外显子在大小上也比较相近.分子进化表明斑马鱼Zar1Zar1L属于两个不同的基因,可能是同一来源的祖先基因重复和进化的结果.RT-PCR结果表明斑马鱼Zar1Zar1L的表达模式相似,都是卵巢特异表达基因,在卵母细胞及早期胚胎中可检测到大量转录本的存在,囊胚、原肠胚期后下降,但在整个胚胎发育期都可检测到转录本.斑马鱼Zar1Zar1L mRNA的表达水平的一致性,似乎暗示着两个基因的功能基本一致.表达模式分析表明Zar1Zar1L可能与斑马鱼卵子-合子转变有关,也可能与其他的胚胎发育过程有关.

  2. Cloning and expression analysis of zygote arrest 1 (Zar1) in New Zealand white rabbits

    Indian Academy of Sciences (India)

    DAN WANG; SHU-YU XIE; WEI ZHANG; CAI-XIA SUN; TAO HUANG; AN-SI WANG; XUE-LEI HAN; GUI-RONG SUN; MING LI

    2017-03-01

    Zygote arrest 1 (Zar1) is an oocyte-specific maternal-effect gene. Previous studies indicate that Zar1 plays important role in early embryo development, but little is known about its function in rabbit. The objectives of this study were to clone the New Zealand white rabbit Zar1 gene and to investigate its expression in various organs in groups of animals with different reproductivetraits.We obtained a 709-bp Zar1 cDNA fragment consisting of an 8-bp exon 1, 161-bp exon 2, 75-bp exon 3, 271-bp exon 4 and 194-bp 3' sequences. The rabbit Zar1 nucleotide sequence showed per cent identities of 91, 88, 88, 87, 86, 87, 76 and 82% with Zar1 orthologues in human, cattle, sheep, pig, mouse, rat, zebrafish and Xenopus laevis, respectively, indicating a high homology with other species and evolutionary conservation. Quantitative real-time polymerase chain reaction analyses revealed nonoocyte-specific Zar1 expression, with expression in spleen, lung, ovary, uterus, heart, liver and kidney. The expression level was highest in the lung. This study may lay the theoretical foundation for the study of ZAR1’s biological function.

  3. The transcriptome of rhizobacteria-induced systemic resistance in Arabidopsis

    NARCIS (Netherlands)

    Verhagen, B.W.M.; Glazebrook, J.; Zhu, T.; Chang, H.-S.; Loon, L.C. van; Pieterse, C.M.J.

    2004-01-01

    Plants develop an enhanced defensive capacity against a broad spectrum of plant pathogens after colonization of the roots by selected strains of nonpathogenic, fluorescent Pseudomonas spp. In Arabidopsis thaliana, this rhizobacteria-induced systemic resistance (ISR) functions independently of salicy

  4. Induced resistance in Arabidopsis and radish; involvement of PR proteins

    OpenAIRE

    HOFFLAND, E.; Pieterse, C. M. J.; Bik, L.; Pelt, J.A. van

    1995-01-01

    This paper demonstrates that Pseudomonas fluorescens strain WCS417 and salicylic acid can induce systemic resistance in radish and Arabidopsis thaliana against Fusarium oxysporum. In neither of the two plant species this induction is associated with induction of PRs. This indicates that PR-accumulation is not a prerequisite for induction of systemic resistance.

  5. Differential induction of systemic resistance in Arabidopsis by biocontrol bacteria

    NARCIS (Netherlands)

    Wees, A.C.M. van; Pieterse, C.M.J.; Trijssenaar, A.; Westende, Y.A.M. van 't; Hartog, F.; Loon, L.C. van

    1997-01-01

    Differential Induction of Systemic Resistance in Arabidopsis by Biocontrol Bacteria. Saskia C. M. Van Wees (1,2), Corné M. J. Pieterse (1,2), Annemiek Trijssenaar (1), Yvonne A. M. Van 't Westende (1), Femke Hartog (1), and Leendert C. Van Loon (1,2). (1) Department of Plant Ecology and Evolutionary

  6. Arabidopsis map kinase 4 negatively regulates systemic acquired resistance

    DEFF Research Database (Denmark)

    Brodersen, P; Johansen, Bo; Petersen, M;

    2000-01-01

    Transposon inactivation of Arabidopsis MAP kinase 4 produced the mpk4 mutant exhibiting constitutive systemic acquired resistance (SAR) including elevated salicylic acid (SA) levels, increased resistance to virulent pathogens, and constitutive pathogenesis-related gene expression shown by Northern...... of NPR1. PDF1.2 and THI2.1 gene induction by jasmonate was blocked in mpk4 expressing NahG, suggesting that MPK4 is required for jasmonic acid-responsive gene expression....

  7. Arabidopsis MAP kinase 4 negatively regulates systemic acquired resistance

    DEFF Research Database (Denmark)

    Petersen, M.; Brodersen, P.; Naested, H.

    2000-01-01

    Transposon inactivation of Arabidopsis MAP kinase 4 produced the mpk4 mutant exhibiting constitutive systemic acquired resistance (SAR) including elevated salicylic acid (SA) revels, increased resistance to virulent pathogens, and constitutive pathogenesis-related gene expression shown by Northern...... of NPR1. PDF1.2 and THI2.1 gene induction by jasmonate was blocked in mpk4 expressing NahG, suggesting that MPK4 is required for jasmonic acid-responsive gene expression....

  8. Arabidopsis YAK1 regulates abscisic acid response and drought resistance

    KAUST Repository

    Kim, Dongjin

    2016-06-06

    Abscisic acid (ABA) is an important phytohormone that controls several plant processes such as seed germination, seedling growth, and abiotic stress response. Here, we report that AtYak1 plays an important role in ABA signaling and postgermination growth in Arabidopsis. AtYak1 knockout mutant plants were hyposensitive to ABA inhibition of seed germination, cotyledon greening, seedling growth, and stomatal movement. atyak1-1 mutant plants display reduced drought stress resistance, as evidenced by water loss rate and survival rate. Molecular genetic analysis revealed that AtYak1 deficiency led to elevated expression of stomatal-related gene, MYB60, and down-regulation of several stress-responsive genes. Altogether, these results indicate that AtYak1 plays a role as a positive regulator in ABA-mediated drought response in Arabidopsis. © 2016 Federation of European Biochemical Societies.

  9. Recombination Rate Heterogeneity within Arabidopsis Disease Resistance Genes.

    Directory of Open Access Journals (Sweden)

    Kyuha Choi

    2016-07-01

    Full Text Available Meiotic crossover frequency varies extensively along chromosomes and is typically concentrated in hotspots. As recombination increases genetic diversity, hotspots are predicted to occur at immunity genes, where variation may be beneficial. A major component of plant immunity is recognition of pathogen Avirulence (Avr effectors by resistance (R genes that encode NBS-LRR domain proteins. Therefore, we sought to test whether NBS-LRR genes would overlap with meiotic crossover hotspots using experimental genetics in Arabidopsis thaliana. NBS-LRR genes tend to physically cluster in plant genomes; for example, in Arabidopsis most are located in large clusters on the south arms of chromosomes 1 and 5. We experimentally mapped 1,439 crossovers within these clusters and observed NBS-LRR gene associated hotspots, which were also detected as historical hotspots via analysis of linkage disequilibrium. However, we also observed NBS-LRR gene coldspots, which in some cases correlate with structural heterozygosity. To study recombination at the fine-scale we used high-throughput sequencing to analyze ~1,000 crossovers within the RESISTANCE TO ALBUGO CANDIDA1 (RAC1 R gene hotspot. This revealed elevated intragenic crossovers, overlapping nucleosome-occupied exons that encode the TIR, NBS and LRR domains. The highest RAC1 recombination frequency was promoter-proximal and overlapped CTT-repeat DNA sequence motifs, which have previously been associated with plant crossover hotspots. Additionally, we show a significant influence of natural genetic variation on NBS-LRR cluster recombination rates, using crosses between Arabidopsis ecotypes. In conclusion, we show that a subset of NBS-LRR genes are strong hotspots, whereas others are coldspots. This reveals a complex recombination landscape in Arabidopsis NBS-LRR genes, which we propose results from varying coevolutionary pressures exerted by host-pathogen relationships, and is influenced by structural heterozygosity.

  10. Recombination Rate Heterogeneity within Arabidopsis Disease Resistance Genes

    Science.gov (United States)

    Serra, Heïdi; Ziolkowski, Piotr A.; Yelina, Nataliya E.; Jackson, Matthew; Mézard, Christine; McVean, Gil; Henderson, Ian R.

    2016-01-01

    Meiotic crossover frequency varies extensively along chromosomes and is typically concentrated in hotspots. As recombination increases genetic diversity, hotspots are predicted to occur at immunity genes, where variation may be beneficial. A major component of plant immunity is recognition of pathogen Avirulence (Avr) effectors by resistance (R) genes that encode NBS-LRR domain proteins. Therefore, we sought to test whether NBS-LRR genes would overlap with meiotic crossover hotspots using experimental genetics in Arabidopsis thaliana. NBS-LRR genes tend to physically cluster in plant genomes; for example, in Arabidopsis most are located in large clusters on the south arms of chromosomes 1 and 5. We experimentally mapped 1,439 crossovers within these clusters and observed NBS-LRR gene associated hotspots, which were also detected as historical hotspots via analysis of linkage disequilibrium. However, we also observed NBS-LRR gene coldspots, which in some cases correlate with structural heterozygosity. To study recombination at the fine-scale we used high-throughput sequencing to analyze ~1,000 crossovers within the RESISTANCE TO ALBUGO CANDIDA1 (RAC1) R gene hotspot. This revealed elevated intragenic crossovers, overlapping nucleosome-occupied exons that encode the TIR, NBS and LRR domains. The highest RAC1 recombination frequency was promoter-proximal and overlapped CTT-repeat DNA sequence motifs, which have previously been associated with plant crossover hotspots. Additionally, we show a significant influence of natural genetic variation on NBS-LRR cluster recombination rates, using crosses between Arabidopsis ecotypes. In conclusion, we show that a subset of NBS-LRR genes are strong hotspots, whereas others are coldspots. This reveals a complex recombination landscape in Arabidopsis NBS-LRR genes, which we propose results from varying coevolutionary pressures exerted by host-pathogen relationships, and is influenced by structural heterozygosity. PMID:27415776

  11. Genetic analysis of induced systemic resistance in Arabidopsis thaliana: association between induced and basal resistance

    NARCIS (Netherlands)

    Ton, J.; Pieterse, C.M.J.; Loon, L.C. van

    1998-01-01

    Selected nonpathogenic rhizobacteria are able to elicit induced systemic resistance (ISR) in plants. Different ecotypes of Arabidopsis thaliana were screened for expression of ISR against infection by Pseudomonas syringae pv. tomato, after treatment of the roots with the nonpathogenic P. fluorescens

  12. Heritability of rhizobacteria-mediated induced systemic resistance and basal resistance in Arabidopsis

    NARCIS (Netherlands)

    Ton, J.; Davison, S.; Loon, L.C. van; Pieterse, C.M.J.

    2001-01-01

    Selected strains of non-pathogenic rhizobacteria have the ability to trigger an induced systemic resistance (ISR) response in plants. In Arabidopsis, rhizobacteria-mediated ISR has been extensively studied, using Pseudomonas fluorescens WCS417r as the inducing agent and P. syringae pv. tomato DC3000

  13. Characterization of Arabidopsis enhanced disease susceptibility mutants that are affected in systemically induced resistance

    NARCIS (Netherlands)

    Ton, J.; Vos, M. de; Robben, C.; Buchala, Anthony; Métraux, Jean-Pierre; Loon, L.C. van; Pieterse, C.M.J.

    2002-01-01

    In Arabidopsis, the rhizobacterial strain Pseudomonas fluorescens WCS417r triggers jasmonate (JA)- and ethylene (ET)-dependent induced systemic resistance (ISR) that is effective against different pathogens. Arabidopsis genotypes unable to express rhizobacteria-mediated ISR against the bacterial pat

  14. Arabidopsis PED2 positively modulates plant drought stress resistance

    Institute of Scientific and Technical Information of China (English)

    Haitao Shi; Tiantian Ye; Fan Yang; Zhulong Chan

    2015-01-01

    Abscisic acid (ABA) is an important phytohormone that functions in seed germination, plant development, and multiple stress responses. Arabidopsis Peroxisome defective 2 (AtPED2) (also known as AtPEXOXIN14, AtPEX14), is involved in the intracellular transport of thiolase from the cytosol to glyoxysomes, and perosisomal matrix protein import in plants. In this study, we assigned a new role for AtPED2 in drought stress resistance. The transcript level of AtPED2 was down-regulated by ABA and abiotic stress treatments. AtPED2 knockout mutants were insensitive to ABA-mediated seed germination, primary root elongation, and stomatal response, while AtPED2 over-expressing plants were sensitive to ABA in comparison to wide type (WT). AtPED2 also positively regulated drought stress resistance, as evidenced by the changes of water loss rate, electrolyte leakage, and survival rate. Notably, AtPED2 positively modulated expression of several stress-responsive genes (RAB18, RD22, RD29A, and RD29B), positively affected underlying antioxidant enzyme activities and negatively regulated reactive oxygen species (ROS) level under drought stress conditions. Moreover, multiple carbon metabolites including amino acids, organic acids, sugars, sugar alcohols, and aromatic amines were also positively regulated by AtPED2. Taken together, these results indicated a positive role for AtPED2 in drought resistance, through modulation of stress-responsive genes expression, ROS metabolism, and metabolic homeostasis, at least partially.

  15. Arabidopsis mutant bik1 exhibits strong resistance to Plasmodiophora brassicae

    Directory of Open Access Journals (Sweden)

    Tao Chen

    2016-09-01

    Full Text Available Botrytis-induced kinase1 (BIK1, a receptor-like cytoplasmic kinase, plays an important role in resistance against pathogens and insects in Arabidopsis thaliana. However, it remains unknown whether BIK1 functions against Plasmodiophora brassicae, an obligate biotrophic protist that attacks cruciferous plants and induces gall formation on roots. Here, we investigated the potential roles of receptors FLS2, BAK1 and BIK1 in the infection of P. brassicae cruciferous plants. Wild-type plants, fls2 and bak1 mutants showed typical symptom on roots, and the galls were filled with large quantities of resting spores, while bik1 mutant plants exhibited strong resistance to P. brassicae. Compared with that of the wild-type plants, the root hair and cortical infection rate of bik1 mutant were significantly reduced by about 40-50%. A considerable portion of bik1 roots failed to form typical galls. Even if some small galls were formed, they were filled with multinucleate secondary plasmodia. The bik1 plants accumulated less reactive oxygen species (ROS at infected roots than other mutants and wild-type plants. Exogenous salicylic acid (SA treatment alleviated the clubroot symptoms in wild-type plants, and the expression of the SA signaling marker gene PR1 was significantly increased in bik1. Both sid2 (salicylic acid induction-deficient 2 and npr1-1 (non-expresser of PR genes that regulate systemic acquired resistance (SAR mutants showed increased susceptibility to P. brassicae compared with wild-type plants. These results suggest that the resistance of bik1 to P. brassicae is possibly mediated by SA inducible mechanisms enhance the resistance to clubroot disease.

  16. Herbivore-induced resistance against microbial pathogens in Arabidopsis

    NARCIS (Netherlands)

    Vos, de M.; Zaanen, van W.; Koornneef, A.; Korzelius, J.P.; Dicke, M.; Loon, van L.C.; Pieterse, C.M.J.

    2006-01-01

    Caterpillars of the herbivore Pieris rapae stimulate the production of jasmonic acid (JA) and ethylene (ET) in Arabidopsis (Arabidopsis thaliana) and trigger a defense response that affects insect performance on systemic tissues. To investigate the spectrum of effectiveness of P. rapae-induced resis

  17. Comparative analysis of drought resistance genes in Arabidopsis and rice

    NARCIS (Netherlands)

    Trijatmiko, K.R.

    2005-01-01

    Keywords: rice, Arabidopsis, drought, genetic mapping,microarray, transcription factor, AP2/ERF, SHINE, wax, stomata, comparative genetics, activation tagging, Ac/Ds, En/IThis thesis describes the use of genomics information and tools from Arabidopsis and

  18. A Lipid Transfer Protein Increases the Glutathione Content and Enhances Arabidopsis Resistance to a Trichothecene Mycotoxin.

    Directory of Open Access Journals (Sweden)

    John E McLaughlin

    Full Text Available Fusarium head blight (FHB or scab is one of the most important plant diseases worldwide, affecting wheat, barley and other small grains. Trichothecene mycotoxins such as deoxynivalenol (DON accumulate in the grain, presenting a food safety risk and health hazard to humans and animals. Despite considerable breeding efforts, highly resistant wheat or barley cultivars are not available. We screened an activation tagged Arabidopsis thaliana population for resistance to trichothecin (Tcin, a type B trichothecene in the same class as DON. Here we show that one of the resistant lines identified, trichothecene resistant 1 (trr1 contains a T-DNA insertion upstream of two nonspecific lipid transfer protein (nsLTP genes, AtLTP4.4 and AtLTP4.5. Expression of both nsLTP genes was induced in trr1 over 10-fold relative to wild type. Overexpression of AtLTP4.4 provided greater resistance to Tcin than AtLTP4.5 in Arabidopsis thaliana and in Saccharomyces cerevisiae relative to wild type or vector transformed lines, suggesting a conserved protection mechanism. Tcin treatment increased reactive oxygen species (ROS production in Arabidopsis and ROS stain was associated with the chloroplast, the cell wall and the apoplast. ROS levels were attenuated in Arabidopsis and in yeast overexpressing AtLTP4.4 relative to the controls. Exogenous addition of glutathione and other antioxidants enhanced resistance of Arabidopsis to Tcin while the addition of buthionine sulfoximine, an inhibitor of glutathione synthesis, increased sensitivity, suggesting that resistance was mediated by glutathione. Total glutathione content was significantly higher in Arabidopsis and in yeast overexpressing AtLTP4.4 relative to the controls, highlighting the importance of AtLTP4.4 in maintaining the redox state. These results demonstrate that trichothecenes cause ROS accumulation and overexpression of AtLTP4.4 protects against trichothecene-induced oxidative stress by increasing the glutathione

  19. An Arabidopsis thaliana ABC transporter that confers kanamycin resistance in transgenic plants does not endow resistance to Escherichia coli

    OpenAIRE

    Burris, Kellie; Mentewab, Ayalew; Ripp, Steven; Stewart, C. Neal

    2007-01-01

    Summary Concerns have been raised about potential horizontal gene transfer (HGT) of antibiotic resistance markers (ARMs) from transgenic plants to bacteria of medical and environmental importance. All ARMs used in transgenic plants have been bacterial in origin, but it has been recently shown that an Arabidopsis thaliana ABC transporter, Atwbc19, confers kanamycin resistance when overexpressed in transgenic plants. Atwbc19 was evaluated for its ability to transfer kanamycin resistance to Esch...

  20. Identification of a locus in Arabidopsis controlling both the expression of rhizobacteria-mediated induced systemic resistance (ISR) and basal resistance against Pseudomonas syringae pv. tomato

    NARCIS (Netherlands)

    Ton, J.; Pieterse, C.M.J.; Loon, L.C. van

    1999-01-01

    Selected nonpathogenic rhizobacteria with biological disease control activity are able to elicit an induced systemic resistance (ISR) response that is phenotypically similar to pathogen-induced systemic acquired resistance (SAR). Ten ecotypes of Arabidopsis thaliana were screened for their potential

  1. Induction of Systemic Resistance against Cucumber mosaic virus in Arabidopsis thaliana by Trichoderma asperellum SKT-1

    Directory of Open Access Journals (Sweden)

    Mohsen Mohamed Elsharkawy

    2013-06-01

    Full Text Available Trichoderma asperellum SKT-1 is a microbial pesticide that is very effective against various diseases. Our study was undertaken to evaluate T. asperellum SKT-1 for induction of resistance against yellow strain of Cucumber mosaic virus (CMV-Y in Arabidopsis plants. Disease severity was rated at 2 weeks post inoculation (WPI. CMV titre in Arabidopsis leaves was determined by indirect enzyme-linked immunosorbent assay (ELISA at 2 WPI. Our results demonstrated that among all Arabidopsis plants treated with barley grain inoculum (BGI of SKT-1 NahG and npr1 plants showed no significant reduction in disease severity and CMV titre as compared with control plants. In contrast, disease severity and CMV titre were significantly reduced in all Arabidopsis plants treated with culture filtrate (CF of SKT-1 as compared with control plants. RT-PCR results showed increased expression levels of SA-inducible genes, but not JA/ET-inducible genes, in leaves of BGI treated plants. Moreover, expression levels of SA- and JA/ET-inducible genes were increased in leaves of CF treated plants. In conclusion, BGI treatment induced systemic resistance against CMV through SA signaling cascade in Arabidopsis plants. While, treatment with CF of SKT-1 mediated the expression of a majority of the various pathogen related genes, which led to the increased defense mechanism against CMV infection.

  2. Etopic expression of "Arabidopsis" H(+)-pyrophosphatase AVP1 enhances drought resistance in bottle gourd

    Science.gov (United States)

    Bottle gourd ("Lagenaria siceraria" Standl.) has been used as a source of rootstock for grafting watermelon to improve its fruit quality. We report here the development of a bottle gourd with resistance to drought by ectopic expression of the "Arabidopsis AVP1" gene that encodes a vacuolar H(+)-pyro...

  3. Broad-spectrum acquired resistance in barley induced by the Pseudomonas pathosystem shares transcriptional components with Arabidopsis systemic acquired resistance.

    Science.gov (United States)

    Colebrook, E H; Creissen, G; McGrann, G R D; Dreos, R; Lamb, C; Boyd, L A

    2012-05-01

    Inducible resistance responses play a central role in the defense of plants against pathogen attack. Acquired resistance (AR) is induced alongside defense toward primary attack, providing broad-spectrum protection against subsequent pathogen challenge. The localization and molecular basis of AR in cereals is poorly understood, in contrast with the well-characterized systemic acquired resistance (SAR) response in Arabidopsis. Here, we use Pseudomonas syringae as a biological inducer of AR in barley, providing a clear frame of reference to the Arabidopsis-P. syringae pathosystem. Inoculation of barley leaf tissue with the nonadapted P. syringae pv. tomato avrRpm1 (PstavrRpm1) induced an active local defense response. Furthermore, inoculation of barley with PstavrRpm1 resulted in the induction of broad-spectrum AR at a distance from the local lesion, "adjacent" AR, effective against compatible isolates of P. syringae and Magnaporthe oryzae. Global transcriptional profiling of this adjacent AR revealed similarities with the transcriptional profile of SAR in Arabidopsis, as well as transcripts previously associated with chemically induced AR in cereals, suggesting that AR in barley and SAR in Arabidopsis may be mediated by analogous pathways.

  4. The Arabidopsis NPR1 gene confers broad-spectrum disease resistance in strawberry.

    Science.gov (United States)

    Silva, Katchen Julliany P; Brunings, Asha; Peres, Natalia A; Mou, Zhonglin; Folta, Kevin M

    2015-08-01

    Although strawberry is an economically important fruit crop worldwide, production of strawberry is limited by its susceptibility to a wide range of pathogens and the lack of major commercial cultivars with high levels of resistance to multiple pathogens. The objective of this study is to ectopically express the Arabidopsis thaliana NPR1 gene (AtNPR1) in the diploid strawberry Fragaria vesca L. and to test transgenic plants for disease resistance. AtNPR1 is a key positive regulator of the long-lasting broad-spectrum resistance known as systemic acquired resistance (SAR) and has been shown to confer resistance to a number of pathogens when overexpressed in Arabidopsis or ectopically expressed in several crop species. We show that ectopic expression of AtNPR1 in strawberry increases resistance to anthracnose, powdery mildew, and angular leaf spot, which are caused by different fungal or bacterial pathogens. The increased resistance is related to the relative expression levels of AtNPR1 in the transgenic plants. In contrast to Arabidopsis plants overexpressing AtNPR1, which grow normally and do not constitutively express defense genes, the strawberry transgenic plants are shorter than non-transformed controls, and most of them fail to produce runners and fruits. Consistently, most of the transgenic lines constitutively express the defense gene FvPR5, suggesting that the SAR activation mechanisms in strawberry and Arabidopsis are different. Nevertheless, our results indicate that overexpression of AtNPR1 holds the potential for generation of broad-spectrum disease resistance in strawberry.

  5. Arabidopsis MAPKKK18 positively regulates drought stress resistance via downstream MAPKK3.

    Science.gov (United States)

    Li, Yuanyuan; Cai, Huixian; Liu, Pu; Wang, Chunyan; Gao, Huiyang; Wu, Changai; Yan, Kang; Zhang, Shizhong; Huang, Jinguang; Zheng, Chengchao

    2017-03-04

    Mitogen-activated protein kinase (MAPK) cascades are conserved and vital signaling components in the responses to various ambient stresses. Here, we report the identification of MAPKKK18, a drought resistance associated MAPK kinase kinase in Arabidopsis. The mapkkk18 knockout mutants displayed hypersensitivity to drought stress, whereas overaccumulation of MAPKKK18 in transgenic Arabidopsis plants significantly enhanced the resistance to drought. Expression pattern analysis revealed that the inducible expression of MAPKKK18 by osmotic stress was ABA and the canonical ABA signaling pathway dependent. Furthermore, MAPKKK18 mainly exerted its regulatory roles via downstream MAPKK3. These findings uncovered important roles for MAPKKK18 in drought resistance and expanded our understanding of the MAPK pathways in modulating abiotic stress responses.

  6. Rhizobacteria-mediated induced systemic resistance in Arabidopsis

    NARCIS (Netherlands)

    Pieterse, C.M.J.; Ton, J.; Wees, A.C.M. van; Hase, S.; Léon-Kloosterziel, K.M.; Verhagen, B.W.M.; Pelt, J.A. van; Loon, L.C. van

    2002-01-01

    Selected strains of rhizosphere bacteria have been shown to reduce disease by activating a resistance mechanism in the plant called rhizobacteria-mediated induced systemic resistance (ISR). ISR resembles pathogen-induced systemic acquired resistance (SAR), in that both types of induced resistance re

  7. The Arabidopsis ISR1 locus is required for rhizobacteria-mediated induced systemic resistance against different pathogens

    OpenAIRE

    Ton, J.; Pelt, J.A. van; Loon, L. C. van; Pieterse, C.M.J.

    2002-01-01

    In Arabidopsis thaliana, non-pathogenic, root-colonizing Pseudomonas fluorescens WCS417r bacteria trigger an induced systemic resistance (ISR) that is phenotypically similar to pathogen-induced systemic acquired resistance (SAR). In contrast to SAR, WCS417r-mediated ISR is controlled by a salicylic acid (SA)-independent signalling pathway that requires an intact response to the plant hormones jasmonic acid (JA) and ethylene (ET). Arabidopsis accessions RLD1 and Ws-0 fail to express ISR agains...

  8. Elevated early callose deposition results in complete penetration resistance to powdery mildew in Arabidopsis.

    Science.gov (United States)

    Ellinger, Dorothea; Naumann, Marcel; Falter, Christian; Zwikowics, Claudia; Jamrow, Torsten; Manisseri, Chithra; Somerville, Shauna C; Voigt, Christian A

    2013-03-01

    A common response by plants to fungal attack is deposition of callose, a (1,3)-β-glucan polymer, in the form of cell wall thickenings called papillae, at site of wall penetration. While it has been generally believed that the papillae provide a structural barrier to slow fungal penetration, this idea has been challenged in recent studies of Arabidopsis (Arabidopsis thaliana), where fungal resistance was found to be independent of callose deposition. To the contrary, we show that callose can strongly support penetration resistance when deposited in elevated amounts at early time points of infection. We generated transgenic Arabidopsis lines that express POWDERY MILDEW RESISTANT4 (PMR4), which encodes a stress-induced callose synthase, under the control of the constitutive 35S promoter. In these lines, we detected callose synthase activity that was four times higher than that in wild-type plants 6 h post inoculation with the virulent powdery mildew Golovinomyces cichoracearum. The callose synthase activity was correlated with enlarged callose deposits and the focal accumulation of green fluorescent protein-tagged PMR4 at sites of attempted fungal penetration. We observed similar results from infection studies with the nonadapted powdery mildew Blumeria graminis f. sp. hordei. Haustoria formation was prevented in resistant transgenic lines during both types of powdery mildew infection, and neither the salicylic acid-dependent nor jasmonate-dependent pathways were induced. We present a schematic model that highlights the differences in callose deposition between the resistant transgenic lines and the susceptible wild-type plants during compatible and incompatible interactions between Arabidopsis and powdery mildew.

  9. UV-induced DNA damage promotes resistance to the biotrophic pathogen Hyaloperonospora parasitica in Arabidopsis.

    Science.gov (United States)

    Kunz, Bernard A; Dando, Paige K; Grice, Desma M; Mohr, Peter G; Schenk, Peer M; Cahill, David M

    2008-10-01

    Plant innate immunity to pathogenic microorganisms is activated in response to recognition of extracellular or intracellular pathogen molecules by transmembrane receptors or resistance proteins, respectively. The defense signaling pathways share components with those involved in plant responses to UV radiation, which can induce expression of plant genes important for pathogen resistance. Such intriguing links suggest that UV treatment might activate resistance to pathogens in normally susceptible host plants. Here, we demonstrate that pre-inoculative UV (254 nm) irradiation of Arabidopsis (Arabidopsis thaliana) susceptible to infection by the biotrophic oomycete Hyaloperonospora parasitica, the causative agent of downy mildew, induces dose- and time-dependent resistance to the pathogen detectable up to 7 d after UV exposure. Limiting repair of UV photoproducts by postirradiation incubation in the dark, or mutational inactivation of cyclobutane pyrimidine dimer photolyase, (6-4) photoproduct photolyase, or nucleotide excision repair increased the magnitude of UV-induced pathogen resistance. In the absence of treatment with 254-nm UV, plant nucleotide excision repair mutants also defective for cyclobutane pyrimidine dimer or (6-4) photoproduct photolyase displayed resistance to H. parasitica, partially attributable to short wavelength UV-B (280-320 nm) radiation emitted by incubator lights. These results indicate UV irradiation can initiate the development of resistance to H. parasitica in plants normally susceptible to the pathogen and point to a key role for UV-induced DNA damage. They also suggest UV treatment can circumvent the requirement for recognition of H. parasitica molecules by Arabidopsis proteins to activate an immune response.

  10. Systemic acquired resistance in soybean is regulated by two proteins, Orthologous to Arabidopsis NPR1

    Directory of Open Access Journals (Sweden)

    Sandhu Devinder

    2009-08-01

    Full Text Available Abstract Background Systemic acquired resistance (SAR is induced in non-inoculated leaves following infection with certain pathogenic strains. SAR is effective against many pathogens. Salicylic acid (SA is a signaling molecule of the SAR pathway. The development of SAR is associated with the induction of pathogenesis related (PR genes. Arabidopsis non-expressor of PR1 (NPR1 is a regulatory gene of the SA signal pathway 123. SAR in soybean was first reported following infection with Colletotrichum trancatum that causes anthracnose disease. We investigated if SAR in soybean is regulated by a pathway, similar to the one characterized in Arabidopsis. Results Pathogenesis-related gene GmPR1 is induced following treatment of soybean plants with the SAR inducer, 2,6-dichloroisonicotinic acid (INA or infection with the oomycete pathogen, Phytophthora sojae. In P. sojae-infected plants, SAR was induced against the bacterial pathogen, Pseudomonas syringae pv. glycinea. Soybean GmNPR1-1 and GmNPR1-2 genes showed high identities to Arabidopsis NPR1. They showed similar expression patterns among the organs, studied in this investigation. GmNPR1-1 and GmNPR1-2 are the only soybean homologues of NPR1and are located in homoeologous regions. In GmNPR1-1 and GmNPR1-2 transformed Arabidopsis npr1-1 mutant plants, SAR markers: (i PR-1 was induced following INA treatment and (ii BGL2 following infection with Pseudomonas syringae pv. tomato (Pst, and SAR was induced following Pst infection. Of the five cysteine residues, Cys82, Cys150, Cys155, Cys160, and Cys216 involved in oligomer-monomer transition in NPR1, Cys216 in GmNPR1-1 and GmNPR1-2 proteins was substituted to Ser and Leu, respectively. Conclusion Complementation analyses in Arabidopsis npr1-1 mutants revealed that homoeologous GmNPR1-1 and GmNPR1-2 genes are orthologous to Arabidopsis NPR1. Therefore, SAR pathway in soybean is most likely regulated by GmNPR1 genes. Substitution of Cys216 residue, essential

  11. Activation tagging of ATHB13 in Arabidopsis thaliana confers broad-spectrum disease resistance.

    Science.gov (United States)

    Gao, Dongli; Appiano, Michela; Huibers, Robin P; Chen, Xi; Loonen, Annelies E H M; Visser, Richard G F; Wolters, Anne-Marie A; Bai, Yuling

    2014-12-01

    Powdery mildew species Oidium neolycopersici (On) can cause serious yield losses in tomato production worldwide. Besides on tomato, On is able to grow and reproduce on Arabidopsis. In this study we screened a collection of activation-tagged Arabidopsis mutants and identified one mutant, 3221, which displayed resistance to On, and in addition showed a reduced stature and serrated leaves. Additional disease tests demonstrated that the 3221 mutant exhibited resistance to downy mildew (Hyaloperonospora arabidopsidis) and green peach aphid (Myzus persicae), but retained susceptibility to bacterial pathogen Pseudomonas syringae pv tomato DC3000. The resistance trait and morphological alteration were mutually linked in 3221. Identification of the activation tag insertion site and microarray analysis revealed that ATHB13, a homeodomain-leucine zipper (HD-Zip) transcription factor, was constitutively overexpressed in 3221. Silencing of ATHB13 in 3221 resulted in the loss of both the morphological alteration and resistance, whereas overexpression of the cloned ATHB13 in Col-0 and Col-eds1-2 backgrounds resulted in morphological alteration and resistance. Microarray analysis further revealed that overexpression of ATHB13 influenced the expression of a large number of genes. Previously, it was reported that ATHB13-overexpressing lines conferred tolerance to abiotic stress. Together with our results, it appears that ATHB13 is involved in the crosstalk between abiotic and biotic stress resistance pathways.

  12. Modified cellulose synthase gene from Arabidopsis thaliana confers herbicide resistance to plants

    Science.gov (United States)

    Somerville, Chris R.; Scheible, Wolf

    2007-07-10

    Cellulose synthase ("CS"), a key enzyme in the biosynthesis of cellulose in plants is inhibited by herbicides comprising thiazolidinones such as 5-tert-butyl-carbamoyloxy-3-(3-trifluromethyl)phenyl-4-thiazolidinone (TZ), isoxaben and 2,6-dichlorobenzonitrile (DCB). Two mutant genes encoding isoxaben and TZ-resistant cellulose synthase have been isolated from isoxaben and TZ-resistant Arabidopsis thaliana mutants. When compared with the gene coding for isoxaben or TZ-sensitive cellulose synthase, one of the resistant CS genes contains a point mutation, wherein glycine residue 998 is replaced by an aspartic acid. The other resistant mutation is due to a threonine to isoleucine change at amino acid residue 942. The mutant CS gene can be used to impart herbicide resistance to a plant; thereby permitting the utilization of the herbicide as a single application at a concentration which ensures the complete or substantially complete killing of weeds, while leaving the transgenic crop plant essentially undamaged.

  13. The Arabidopsis ISR1 locus controlling rhizobacteria-mediated induced systemic resistance is involved in ethylene signaling

    OpenAIRE

    Ton, J.; Davison, S; Wees, A.C.M. van; Loon, L. C. van; Pieterse, C.M.J.

    2001-01-01

    In Arabidopsis, the rhizobacterial strain Pseudomonas fluorescens WCS417r triggers an induced systemic resistance (ISR) response that is effective against different types of pathogens. The ISR signaling pathway functions independent of salicylic acid, but requires responsiveness to jasmonate (JA) and ethylene. Using the genetic variability of ISR inducibility between Arabidopsis accessions, we recently identified a locus (ISR1) on chromosome III that is involved in ISR signaling. Accessions R...

  14. A Conserved Carboxylesterase Is a SUPPRESSOR OF AVRBST-ELICITED RESISTANCE in Arabidopsis[W][OA

    Science.gov (United States)

    Cunnac, Sébastien; Wilson, Ariane; Nuwer, Jamie; Kirik, Angela; Baranage, Gayathri; Mudgett, Mary Beth

    2007-01-01

    AvrBsT is a type III effector from Xanthomonas campestris pv vesicatoria that is translocated into plant cells during infection. AvrBsT is predicted to encode a Cys protease that targets intracellular host proteins. To dissect AvrBsT function and recognition in Arabidopsis thaliana, 71 ecotypes were screened to identify lines that elicit an AvrBsT-dependent hypersensitive response (HR) after Xanthomonas campestris pv campestris (Xcc) infection. The HR was observed only in the Pi-0 ecotype infected with Xcc strain 8004 expressing AvrBsT. To create a robust pathosystem to study AvrBsT immunity in Arabidopsis, the foliar pathogen Pseudomonas syringae pv tomato (Pst) strain DC3000 was engineered to translocate AvrBsT into Arabidopsis by the Pseudomonas type III secretion (T3S) system. Pi-0 leaves infected with Pst DC3000 expressing a Pst T3S signal fused to AvrBsT-HA (AvrBsTHYB-HA) elicited HR and limited pathogen growth, confirming that the HR leads to defense. Resistance in Pi-0 is caused by a recessive mutation predicted to inactivate a carboxylesterase known to hydrolyze lysophospholipids and acylated proteins in eukaryotes. Transgenic Pi-0 plants expressing the wild-type Columbia allele are susceptible to Pst DC3000 AvrBsTHYB-HA infection. Furthermore, wild-type recombinant protein cleaves synthetic p-nitrophenyl ester substrates in vitro. These data indicate that the carboxylesterase inhibits AvrBsT-triggered phenotypes in Arabidopsis. Here, we present the cloning and characterization of the SUPPRESSOR OF AVRBST-ELICITED RESISTANCE1. PMID:17293566

  15. A conserved carboxylesterase is a SUPPRESSOR OF AVRBST-ELICITED RESISTANCE in Arabidopsis.

    Science.gov (United States)

    Cunnac, Sébastien; Wilson, Ariane; Nuwer, Jamie; Kirik, Angela; Baranage, Gayathri; Mudgett, Mary Beth

    2007-02-01

    AvrBsT is a type III effector from Xanthomonas campestris pv vesicatoria that is translocated into plant cells during infection. AvrBsT is predicted to encode a Cys protease that targets intracellular host proteins. To dissect AvrBsT function and recognition in Arabidopsis thaliana, 71 ecotypes were screened to identify lines that elicit an AvrBsT-dependent hypersensitive response (HR) after Xanthomonas campestris pv campestris (Xcc) infection. The HR was observed only in the Pi-0 ecotype infected with Xcc strain 8004 expressing AvrBsT. To create a robust pathosystem to study AvrBsT immunity in Arabidopsis, the foliar pathogen Pseudomonas syringae pv tomato (Pst) strain DC3000 was engineered to translocate AvrBsT into Arabidopsis by the Pseudomonas type III secretion (T3S) system. Pi-0 leaves infected with Pst DC3000 expressing a Pst T3S signal fused to AvrBsT-HA (AvrBsTHYB-HA) elicited HR and limited pathogen growth, confirming that the HR leads to defense. Resistance in Pi-0 is caused by a recessive mutation predicted to inactivate a carboxylesterase known to hydrolyze lysophospholipids and acylated proteins in eukaryotes. Transgenic Pi-0 plants expressing the wild-type Columbia allele are susceptible to Pst DC3000 AvrBsTHYB-HA infection. Furthermore, wild-type recombinant protein cleaves synthetic p-nitrophenyl ester substrates in vitro. These data indicate that the carboxylesterase inhibits AvrBsT-triggered phenotypes in Arabidopsis. Here, we present the cloning and characterization of the SUPPRESSOR OF AVRBST-ELICITED RESISTANCE1.

  16. Host-plant resistance to western flower thrips in Arabidopsis

    NARCIS (Netherlands)

    Thoen, Manus P.M.

    2016-01-01

    Western flower thrips is a pest on a large variety of vegetable, fruit and ornamental crops. The damage these minute slender insects cause in agriculture through feeding and the transmission of tospoviruses requires a sustainable solution. Host-plant resistance is a cornerstone of Integrated Pest Ma

  17. Signalling in rhizobacteria-induced systemic resistance in Arabidopsis thaliana

    NARCIS (Netherlands)

    Pieterse, C.M.J.; Wees, A.C.M. van; Ton, J.; Pelt, J.A. van; Loon, L.C. van

    2002-01-01

    To protect themselves from disease, plants have evolved sophisticated defence mechanisms in which the signal molecules salicylic acid, jasmonic acid and ethylene often play crucial roles. Elucidation of signalling pathways controlling disease resistance is a major objective in research on plant-path

  18. The relationship between basal and induced resistance in Arabidopsis

    NARCIS (Netherlands)

    Ton, J.; Pieterse, C.M.J.; Loon, L.C. van

    2006-01-01

    Plants are constantly exposed to potentially pathogenic micro-organisms. They possess an extensive array of passive and active defense mechanisms, and only a small proportion of micro-organisms are capable of infecting the plant and causing disease. Plant resistance can be broadly defined as the pla

  19. Rhizobacteria-mediated induced systemic resistence in Arabidopsis

    NARCIS (Netherlands)

    Ton, J.

    2001-01-01

    Upon primary pathogen attack, plants activate a diverse array of defense mechanisms at the site of primary infection. Besides this so-called basal resistance, plants have also the ability to enhance their defensive capacity against future pathogen attack. There are at least two types of biolog

  20. Induced systemic resistance in cucumber and Arabidopsis thaliana by the combination of Trichoderma harzianum Tr6 and Pseudomonas sp.

    NARCIS (Netherlands)

    Alizadeh, H.; Behboudi, K.; Amadzadeh, M.; Javan-Nikkhah, M.; Zamioudis, C; Pieterse, C.M.J.; Bakker, P.A.H.M.

    2013-01-01

    Trichoderma species and fluorescent Pseudomonas spp. have been reported to induce systemic resistance in plants. In this study the effectiveness of a combination of these biological control agents on the efficacy of induced resistance was investigated in cucumber and the model plant Arabidopsis thal

  1. HOPM1 mediated disease resistance to Pseudomonas syringae in Arabidopsis

    Science.gov (United States)

    He, Sheng Yang [Okemos, MI; Nomura, Kinya [East Lansing, MI

    2011-11-15

    The present invention relates to compositions and methods for enhancing plant defenses against pathogens. More particularly, the invention relates to enhancing plant immunity against bacterial pathogens, wherein HopM1.sub.1-300 mediated protection is enhanced, such as increased protection to Pseudomonas syringae pv. tomato DC3000 HopM1 and/or there is an increase in activity of an ATMIN associated plant protection protein, such as ATMIN7. Reagents of the present invention further provide a means of studying cellular trafficking while formulations of the present inventions provide increased pathogen resistance in plants.

  2. Arabidopsis Heterotrimeric G-protein Regulates Cell Wall Defense and Resistance to Necrotrophic Fungi

    Institute of Scientific and Technical Information of China (English)

    Magdalena Delcado-Cerezo; Paul Schulze-Lefert; Shauna Somerville; José Manuel Estevez; Staffan Persson; Antonio Molina; Clara Sánchez-Rodríguez; Viviana Escudero; Eva Miedes; Paula Virginia Fernández; Lucía Jordá; Camilo Hernández-Blanco; Andrea Sánchez-Vallet; Pawel Bednarek

    2012-01-01

    The Arabidopsis heterotrimeric G-protein controls defense responses to necrotrophic and vascular fungi.The agb1 mutant impaired in the Gβ subunit displays enhanced susceptibility to these pathogens.Gβ/AGB1 forms an obligate dimer with either one of the Arabidopsis Gγ subunits (γ1/AGG1 and γ2/AGG2).Accordingly,we now demonstrate that the agg1 agg2 double mutant is as susceptible as agb1 plants to the necrotrophic fungus Plectosphaerella cucumerina.To elucidate the molecular basis of heterotrimeric G-protein-mediated resistance,we performed a comparative transcriptomic analysis of agb1-1 mutant and wild-type plants upon inoculation with P cucumerina.This analysis,together with metabolomic studies,demonstrated that G-protein-mediated resistance was independent of defensive pathways required for resistance to necrotrophic fungi,such as the salicylic acid,jasmonic acid,ethylene,abscisic acid,and tryptophan-derived metabolites signaling,as these pathways were not impaired in agb1 and agg1 agg2 mutants.Notably,many mis-regulated genes in agb1 plants were related with cell wall functions,which was also the case in agg1 agg2 mutant.Biochemical analyses and Fourier Transform InfraRed (FTIR) spectroscopy of cell walls from G-protein mutants revealed that the xylose content was lower in agb1 and agg1 agg2 mutants than in wild-type plants,and that mutant walls had similar FTIR spectratypes,which differed from that of wild-type plants.The data presented here suggest a canonical functionality of the Gβ and Gγ1/γ2 subunits in the control of Arabidopsis immune responses and the regulation of cell wall composition.

  3. Nucleoporins Nup160 and Seh1 are required for disease resistance in Arabidopsis.

    Science.gov (United States)

    Roth, Charlotte; Wiermer, Marcel

    2012-10-01

    Arabidopsis Nup160 and Seh1, encoding two predicted nucleoporins of the Nup107-160 nuclear pore sub-complex, were identified in a reverse genetics screen based on their requirement for basal disease resistance. Both genes also contribute to immunity conferred by Toll interleukin 1 receptor/nucleotide-binding/leucine-rich repeat (TNL)-type R proteins and constitutive resistance activated in the deregulated TNL mutant, snc1. Protein amounts of EDS1, a central regulator of TNL-triggered resistance, are reduced in seh1 and severely depleted in nup160 single mutants. Here, we investigate the impact of mutations in Nup160, Seh1 and a third complex member, MOS3/Nup96, on EDS1 protein accumulation in the snc1 auto-immune mutant background. In addition, we examine the subcellular localization of Seh1 in root tissues.

  4. Herbicide-resistance conferred by expression of a catalytic antibody in Arabidopsis thaliana.

    Science.gov (United States)

    Weiss, Yael; Shulman, Avidor; Ben Shir, Irina; Keinan, Ehud; Wolf, Shmuel

    2006-06-01

    Engineering herbicide resistance in crops facilitates control of weed species, particularly those that are closely related to the crop, and may be useful in selecting lines that have undergone multiple transformation events. Here we show that herbicide-resistant plants can be engineered by designing an herbicide and expressing a catalytic antibody that destroys the herbicide in planta. First, we developed a carbamate herbicide that can be catalytically destroyed by the aldolase antibody 38C2. This compound has herbicidal activity on all three plant species tested. Second, the light chain and half of the heavy chain (Fab) of the catalytic antibody were targeted to the endoplasmic reticulum in two classes of Arabidopsis thaliana transformants. Third, the two transgenic plants were crossed to produce an herbicide-resistant F1 hybrid. The in vitro catalytic activity of the protein from F1 hybrids corroborates that catalytic antibodies can be constitutively expressed in transgenic plants, and that they can confer a unique trait.

  5. Tomato plants ectopically expressing Arabidopsis CBF1 show enhanced resistance to water deficit stress.

    Science.gov (United States)

    Hsieh, Tsai-Hung; Lee, Jent-turn; Charng, Yee-yung; Chan, Ming-Tsair

    2002-10-01

    A DNA cassette containing an Arabidopsis C repeat/dehydration-responsive element binding factor 1 (CBF1) cDNA and a nos terminator, driven by a cauliflower mosaic virus 35S promoter, was transformed into the tomato (Lycopersicon esculentum) genome. These transgenic tomato plants were more resistant to water deficit stress than the wild-type plants. The transgenic plants exhibited growth retardation by showing dwarf phenotype, and the fruit and seed numbers and fresh weight of the transgenic tomato plants were apparently less than those of the wild-type plants. Exogenous gibberellic acid treatment reversed the growth retardation and enhanced growth of transgenic tomato plants, but did not affect the level of water deficit resistance. The stomata of the transgenic CBF1 tomato plants closed more rapidly than the wild type after water deficit treatment with or without gibberellic acid pretreatment. The transgenic tomato plants contained higher levels of Pro than those of the wild-type plants under normal or water deficit conditions. Subtractive hybridization was used to isolate the responsive genes to heterologous CBF1 in transgenic tomato plants and the CAT1 (CATALASE1) was characterized. Catalase activity increased, and hydrogen peroxide concentration decreased in transgenic tomato plants compared with the wild-type plants with or without water deficit stress. These results indicated that the heterologous Arabidopsis CBF1 can confer water deficit resistance in transgenic tomato plants.

  6. Induction of Systemic Resistance against Aphids by Endophytic Bacillus velezensis YC7010 via Expressing PHYTOALEXIN DEFICIENT4 in Arabidopsis

    Science.gov (United States)

    Rashid, Md. Harun-Or-; Khan, Ajmal; Hossain, Mohammad T.; Chung, Young R.

    2017-01-01

    Aphids are the most destructive insect pests. They suck the sap and transmit plant viruses, causing widespread yield loss of many crops. A multifunctional endophytic bacterial strain Bacillus velezensis YC7010 has been found to induce systemic resistance against bacterial and fungal pathogens of rice. However, its activity against insects attack and underlying cellular and molecular defense mechanisms are not elucidated yet. Here, we show that root drenching of Arabidopsis seedlings with B. velezensis YC7010 can induce systemic resistance against green peach aphid (GPA), Myzus persicae. Treatment of bacterial suspension of B. velezensis YC7010 at 2 × 107 CFU/ml to Arabidopsis rhizosphere induced higher accumulation of hydrogen peroxide, cell death, and callose deposition in leaves compared to untreated plants at 6 days after infestation of GPA. Salicylic acid, jasmonic acid, ethylene, and abscisic acid were not required to confer defense against GPA in Arabidopsis plants treated by B. velezensis YC7010. Bacterial treatment with B. velezensis YC7010 significantly reduced settling, feeding and reproduction of GPA on Arabidopsis leaves via strongly expressing senescence-promoting gene PHYTOALEXIN DEFICIENT4 (PAD4) while suppressing BOTRYTIS-INDUCED KINASE1 (BIK1). These results indicate that B. velezensis YC7010-induced systemic resistance to the GPA is a hypersensitive response mainly dependent on higher expression of PAD4 with suppression of BIK1, resulting in more accumulation of hydrogen peroxide, cell death, and callose deposition in Arabidopsis. PMID:28261260

  7. Induction of Systemic Resistance against Aphids by Endophytic Bacillus velezensis YC7010 via Expressing PHYTOALEXIN DEFICIENT4 in Arabidopsis.

    Science.gov (United States)

    Rashid, Md Harun-Or-; Khan, Ajmal; Hossain, Mohammad T; Chung, Young R

    2017-01-01

    Aphids are the most destructive insect pests. They suck the sap and transmit plant viruses, causing widespread yield loss of many crops. A multifunctional endophytic bacterial strain Bacillus velezensis YC7010 has been found to induce systemic resistance against bacterial and fungal pathogens of rice. However, its activity against insects attack and underlying cellular and molecular defense mechanisms are not elucidated yet. Here, we show that root drenching of Arabidopsis seedlings with B. velezensis YC7010 can induce systemic resistance against green peach aphid (GPA), Myzus persicae. Treatment of bacterial suspension of B. velezensis YC7010 at 2 × 10(7) CFU/ml to Arabidopsis rhizosphere induced higher accumulation of hydrogen peroxide, cell death, and callose deposition in leaves compared to untreated plants at 6 days after infestation of GPA. Salicylic acid, jasmonic acid, ethylene, and abscisic acid were not required to confer defense against GPA in Arabidopsis plants treated by B. velezensis YC7010. Bacterial treatment with B. velezensis YC7010 significantly reduced settling, feeding and reproduction of GPA on Arabidopsis leaves via strongly expressing senescence-promoting gene PHYTOALEXIN DEFICIENT4 (PAD4) while suppressing BOTRYTIS-INDUCED KINASE1 (BIK1). These results indicate that B. velezensis YC7010-induced systemic resistance to the GPA is a hypersensitive response mainly dependent on higher expression of PAD4 with suppression of BIK1, resulting in more accumulation of hydrogen peroxide, cell death, and callose deposition in Arabidopsis.

  8. Reporter-based screen for Arabidopsis mutants com-promised in nonhost resistance

    Institute of Scientific and Technical Information of China (English)

    CHEN HuaMin; PAN JunSong; ZHAO XiuXiang; ZHOU JianMin; CAI Run

    2008-01-01

    Plants are exposed to many potentially pathogenic microbes in the environment, but each species is only susceptible to a limited number of pathogens. The broad resistance is referred to as nonhost re-sistance. To date, little is known about the underlying mechanism of nonhost resistance and the sig-naling transduction process. Here we describe a simple method for isolating Arabidopsis nonhost re-sistance mutants against a nonadapted bacterial pathogen. A RAP2.6 promoter-driven LUC reporter system was developed to replace the tedious bacterial growth assay during the primary screening. The RAP2.6-LUC reporter gone is normally induced by the virulent bacterium Pseudomonas syringae pv tomato but not the nonadapted bacterium P. syringae pv phaseolicola. By using this method we iso-lated 4 mutants displaying strong reporter activity in response to P. syringae pv phaseolicola, which were characterized in some details, ebsl, ebs2, ebs3, and ebs4 (enhanced bacterial susceptibility) were compromised in resistance against P. syringae pv phaseolicola and/or P. syringae pv tomato. In addi-tion, ebs4 showed enhanced hypersensitive response to the incompatible bacterium P. syringae pv tomato (avrB). These results demonstrated that the method is suited for large scale screening for nonhost resistance mutants.

  9. Epistatic interactions among herbicide resistances in Arabidopsis thaliana: the fitness cost of multiresistance.

    Science.gov (United States)

    Roux, Fabrice; Camilleri, Christine; Giancola, Sandra; Brunel, Dominique; Reboud, Xavier

    2005-11-01

    The type of interactions among deleterious mutations is considered to be crucial in numerous areas of evolutionary biology, including the evolution of sex and recombination, the evolution of ploidy, the evolution of selfing, and the conservation of small populations. Because the herbicide resistance genes could be viewed as slightly deleterious mutations in the absence of the pesticide selection pressure, the epistatic interactions among three herbicide resistance genes (acetolactate synthase CSR, cellulose synthase IXR1, and auxin-induced AXR1 target genes) were estimated in both the homozygous and the heterozygous states, giving 27 genotype combinations in the model plant Arabidopsis thaliana. By analyzing eight quantitative traits in a segregating population for the three herbicide resistances in the absence of herbicide, we found that most interactions in both the homozygous and the heterozygous states were best explained by multiplicative effects (each additional resistance gene causes a comparable reduction in fitness) rather than by synergistic effects (each additional resistance gene causes a disproportionate fitness reduction). Dominance coefficients of the herbicide resistance cost ranged from partial dominance to underdominance, with a mean dominance coefficient of 0.07. It was suggested that the csr1-1, ixr1-2, and axr1-3 resistance alleles are nearly fully recessive for the fitness cost. More interestingly, the dominance of a specific resistance gene in the absence of herbicide varied according to, first, the presence of the other resistance genes and, second, the quantitative trait analyzed. These results and their implications for multiresistance evolution are discussed in relation to the maintenance of polymorphism at resistance loci in a heterogeneous environment.

  10. Modified cellulose synthase gene from 'Arabidopsis thaliana' confers herbicide resistance to plants

    Energy Technology Data Exchange (ETDEWEB)

    Somerville, Chris R.; Scieble, Wolf

    2000-10-11

    Cellulose synthase ('CS'), a key enzyme in the biosynthesis of cellulose in plants is inhibited by herbicides comprising thiazolidinones such as 5-tert-butyl-carbamoyloxy-3-(3-trifluromethyl) phenyl-4-thiazolidinone (TZ), isoxaben and 2,6-dichlorobenzonitrile (DCB). Two mutant genes encoding isoxaben and TZ-resistant cellulose synthase have been isolated from isoxaben and TZ-resistant Arabidopsis thaliana mutants. When compared with the gene coding for isoxaben or TZ-sensitive cellulose synthase, one of the resistant CS genes contains a point mutation, wherein glycine residue 998 is replaced by an aspartic acid. The other resistant mutation is due to a threonine to isoleucine change at amino acid residue 942. The mutant CS gene can be used to impart herbicide resistance to a plant; thereby permitting the utilization of the herbicide as a single application at a concentration which ensures the complete or substantially complete killing of weeds, while leaving the transgenic crop plant essentially undamaged.

  11. Systemic resistance in Arabidopsis induced by rhizobacteria requires ethylene-dependent signaling at the site of application

    NARCIS (Netherlands)

    Knoester, M.; Pieterse, C.M.J.; Bol, J.F.; Loon, L.C. van

    1999-01-01

    Root colonization of Arabidopsis thaliana by the nonpathogenic, rhizosphere-colonizing, biocontrol bacterium Pseudomonas fluorescens WCS417r has been shown to elicit induced systemic resistance (ISR) against Pseudomonas syringae pv. tomato (Pst). The ISR response differs from the pathogen-inducible

  12. Endogenous cytokinin overproduction modulates ROS homeostasis and decreases salt stress resistance in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Yanping eWang

    2015-11-01

    Full Text Available Cytokinins in plants are crucial for numerous biological processes, including seed germination, cell division and differentiation, floral initiation and adaptation to abiotic stresses. The salt stress can promote reactive oxygen species (ROS production in plants which are highly toxic and ultimately results in oxidative stress. However, the correlation between endogenous cytokinin production and ROS homeostasis in responding to salt stress is poorly understood. In this study, we analyzed the correlation of overexpressing the cytokinin biosynthetic gene AtIPT8 (adenosine phosphate-isopentenyl transferase 8 and the response of salt stress in Arabidopsis. Overproduction of cytokinins, which was resulted by the inducible overexpression of AtIPT8, significantly inhibited the primary root growth and true leaf emergence, especially under the conditions of exogenous salt, glucose and mannitol treatments. Upon cytokinin overproduction, the salt stress resistance was declined, and resulted in less survival rates and chlorophyll content. Interestingly, ROS production was obviously increased with the salt treatment, accompanied by endogenously overproduced cytokinins. The activities of CAT and SOD, which are responsible for scavenging ROS, were also affected. Transcription profiling revealed that the differential expressions of ROS-producing and scavenging related genes, the photosynthesis-related genes and stress responsive genes were existed in transgenic plants of overproducing cytokinins. Our results suggested that broken in the homeostasis of cytokinins in plant cells could modulate the salt stress responses through a ROS-mediated regulation in Arabidopsis.

  13. Endogenous Cytokinin Overproduction Modulates ROS Homeostasis and Decreases Salt Stress Resistance in Arabidopsis Thaliana.

    Science.gov (United States)

    Wang, Yanping; Shen, Wenzhong; Chan, Zhulong; Wu, Yan

    2015-01-01

    Cytokinins in plants are crucial for numerous biological processes, including seed germination, cell division and differentiation, floral initiation and adaptation to abiotic stresses. The salt stress can promote reactive oxygen species (ROS) production in plants which are highly toxic and ultimately results in oxidative stress. However, the correlation between endogenous cytokinin production and ROS homeostasis in responding to salt stress is poorly understood. In this study, we analyzed the correlation of overexpressing the cytokinin biosynthetic gene AtIPT8 (adenosine phosphate-isopentenyl transferase 8) and the response of salt stress in Arabidopsis. Overproduction of cytokinins, which was resulted by the inducible overexpression of AtIPT8, significantly inhibited the primary root growth and true leaf emergence, especially under the conditions of exogenous salt, glucose and mannitol treatments. Upon cytokinin overproduction, the salt stress resistance was declined, and resulted in less survival rates and chlorophyll content. Interestingly, ROS production was obviously increased with the salt treatment, accompanied by endogenously overproduced cytokinins. The activities of catalase (CAT) and superoxide dismutase (SOD), which are responsible for scavenging ROS, were also affected. Transcription profiling revealed that the differential expressions of ROS-producing and scavenging related genes, the photosynthesis-related genes and stress responsive genes were existed in transgenic plants of overproducing cytokinins. Our results suggested that broken in the homeostasis of cytokinins in plant cells could modulate the salt stress responses through a ROS-mediated regulation in Arabidopsis.

  14. The Arabidopsis lectin receptor kinase LecRK-I.9 enhances resistance to Phytophthora infestans in Solanaceous plants.

    Science.gov (United States)

    Bouwmeester, Klaas; Han, Miao; Blanco-Portales, Rosario; Song, Wei; Weide, Rob; Guo, Li-Yun; van der Vossen, Edwin A G; Govers, Francine

    2014-01-01

    Late blight caused by the plant pathogenic oomycete Phytophthora infestans is known as one of the most destructive potato diseases. Plant breeders tend to employ NB-LRR-based resistance for introducing genetically controlled late blight resistance in their breeding lines. However, P. infestans is able to rapidly escape this type of resistance, and hence, NB-LRR-based resistance in potato cultivars is often not durable. Previously, we identified a novel type of Phytophthora resistance in Arabidopsis. This resistance is mediated by the cell surface receptor LecRK-I.9, which belongs to the family of L-type lectin receptor kinases. In this study, we report that expression of the Arabidopsis LecRK-I.9 gene in potato and Nicotiana benthamiana results in significantly enhanced late blight resistance. Transcriptional profiling showed strong reduction in salicylic acid (SA)-mediated defence gene expression in LecRK-I.9 transgenic potato lines (TPLs). In contrast, transcripts of two protease inhibitor genes accumulated to extreme high levels, suggesting that LecRK-I.9-mediated late blight resistance is relying on a defence response that includes activation of protease inhibitors. These results demonstrate that the functionality of LecRK-I.9 in Phytophthora resistance is maintained after interfamily transfer to potato and N. benthamiana and suggest that this novel type of LecRK-based resistance can be exploited in breeding strategies to improve durable late blight resistance in Solanaceous crops.

  15. Hydrogen sulfide regulates abiotic stress tolerance and biotic stress resistance in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Haitao Shi; Tiantian Ye; Ning Han; Hongwu Bian; Xiaodong Liu; Zhulong Chan

    2015-01-01

    Hydrogen sulfide (H2S) is an important gaseous molecule in various plant developmental processes and plant stress responses. In this study, the transgenic Arabidopsis thaliana plants with modulated expressions of two cysteine desulfhydrases, and exogenous H2S donor (sodium hydrosulfide, NaHS) and H2S scavenger (hypotaurine, HT) pre-treated plants were used to dissect the involvement of H2S in plant stress responses. The cysteine desulfhydrases overexpressing plants and NaHS pre-treated plants exhibited higher endogenous H2S level and improved abiotic stress tolerance and biotic stress resistance, while cysteine desulfhydrases knockdown plants and HT pre-treated plants displayed lower endogenous H2S level and decreased stress resistance. Moreover, H2S upregulated the transcripts of multiple abiotic and biotic stress-related genes, and inhibited reactive oxygen species (ROS) accumulation. Interest-ingly, MIR393-mediated auxin signaling including MIR393a/b and their target genes (TIR1, AFB1, AFB2, and AFB3) was transcrip-tional y regulated by H2S, and was related with H2S-induced antibacterial resistance. Moreover, H2S regulated 50 carbon metabolites including amino acids, organic acids, sugars, sugar alcohols, and aromatic amines. Taken together, these results indicated that cysteine desulfhydrase and H2S conferred abiotic stress tolerance and biotic stress resistance, via affecting the stress-related gene expressions, ROS metabolism, metabolic homeostasis, and MIR393-targeted auxin receptors.

  16. Hydrogen sulfide regulates abiotic stress tolerance and biotic stress resistance in Arabidopsis.

    Science.gov (United States)

    Shi, Haitao; Ye, Tiantian; Han, Ning; Bian, Hongwu; Liu, Xiaodong; Chan, Zhulong

    2015-07-01

    Hydrogen sulfide (H2S) is an important gaseous molecule in various plant developmental processes and plant stress responses. In this study, the transgenic Arabidopsis thaliana plants with modulated expressions of two cysteine desulfhydrases, and exogenous H2S donor (sodium hydrosulfide, NaHS) and H2S scavenger (hypotaurine, HT) pre-treated plants were used to dissect the involvement of H2S in plant stress responses. The cysteine desulfhydrases overexpressing plants and NaHS pre-treated plants exhibited higher endogenous H2S level and improved abiotic stress tolerance and biotic stress resistance, while cysteine desulfhydrases knockdown plants and HT pre-treated plants displayed lower endogenous H2S level and decreased stress resistance. Moreover, H2S upregulated the transcripts of multiple abiotic and biotic stress-related genes, and inhibited reactive oxygen species (ROS) accumulation. Interestingly, MIR393-mediated auxin signaling including MIR393a/b and their target genes (TIR1, AFB1, AFB2, and AFB3) was transcriptionally regulated by H2S, and was related with H2S-induced antibacterial resistance. Moreover, H2S regulated 50 carbon metabolites including amino acids, organic acids, sugars, sugar alcohols, and aromatic amines. Taken together, these results indicated that cysteine desulfhydrase and H2S conferred abiotic stress tolerance and biotic stress resistance, via affecting the stress-related gene expressions, ROS metabolism, metabolic homeostasis, and MIR393-targeted auxin receptors.

  17. Arabidopsis thaliana resistance to fusarium oxysporum 2 implicates tyrosine-sulfated peptide signaling in susceptibility and resistance to root infection.

    Directory of Open Access Journals (Sweden)

    Yunping Shen

    2013-05-01

    Full Text Available In the plant Arabidopsis thaliana, multiple quantitative trait loci (QTLs, including RFO2, account for the strong resistance of accession Columbia-0 (Col-0 and relative susceptibility of Taynuilt-0 (Ty-0 to the vascular wilt fungus Fusarium oxysporum forma specialis matthioli. We find that RFO2 corresponds to diversity in receptor-like protein (RLP genes. In Col-0, there is a tandem pair of RLP genes: RFO2/At1g17250 confers resistance while RLP2 does not. In Ty-0, the highly diverged RFO2 locus has one RLP gene conferring weaker resistance. While the endogenous RFO2 makes a modest contribution to resistance, transgenic RFO2 provides strong pathogen-specific resistance. The extracellular leucine-rich repeats (eLRRs in RFO2 and RLP2 are interchangeable for resistance and remarkably similar to eLRRs in the receptor-like kinase PSY1R, which perceives tyrosine-sulfated peptide PSY1. Reduced infection in psy1r and mutants of related phytosulfokine (PSK receptor genes PSKR1 and PSKR2 shows that tyrosine-sulfated peptide signaling promotes susceptibility. The related eLRRs in RFO2 and PSY1R are not interchangeable; and expression of the RLP nPcR, in which eLRRs in RFO2 are replaced with eLRRs in PSY1R, results in constitutive resistance. Counterintuitively, PSY1 signaling suppresses nPcR because psy1r nPcR is lethal. The fact that PSK signaling does not similarly affect nPcR argues that PSY1 signaling directly downregulates the expression of nPcR. Our results support a speculative but intriguing model to explain RFO2's role in resistance. We propose that F. oxysporum produces an effector that inhibits the normal negative feedback regulation of PSY1R, which stabilizes PSY1 signaling and induces susceptibility. However, RFO2, acting as a decoy receptor for PSY1R, is also stabilized by the effector and instead induces host immunity. Overall, the quantitative resistance of RFO2 is reminiscent of the better-studied monogenic resistance traits.

  18. Differential effectiveness of microbially induced resistance against herbivorous insects in Arabidopsis.

    Science.gov (United States)

    Van Oosten, Vivian R; Bodenhausen, Natacha; Reymond, Philippe; Van Pelt, Johan A; Van Loon, L C; Dicke, Marcel; Pieterse, Corné M J

    2008-07-01

    Rhizobacteria-induced systemic resistance (ISR) and pathogen-induced systemic acquired resistance (SAR) have a broad, yet partly distinct, range of effectiveness against pathogenic microorganisms. Here, we investigated the effectiveness of ISR and SAR in Arabidopsis against the tissue-chewing insects Pieris rapae and Spodoptera exigua. Resistance against insects consists of direct defense, such as the production of toxins and feeding deterrents and indirect defense such as the production of plant volatiles that attract carnivorous enemies of the herbivores. Wind-tunnel experiments revealed that ISR and SAR did not affect herbivore-induced attraction of the parasitic wasp Cotesia rubecula (indirect defense). By contrast, ISR and SAR significantly reduced growth and development of the generalist herbivore S. exigua, although not that of the specialist P. rapae. This enhanced direct defense against S. exigua was associated with potentiated expression of the defense-related genes PDF1.2 and HEL. Expression profiling using a dedicated cDNA microarray revealed four additional, differentially primed genes in microbially induced S. exigua-challenged plants, three of which encode a lipid-transfer protein. Together, these results indicate that microbially induced plants are differentially primed for enhanced insect-responsive gene expression that is associated with increased direct defense against the generalist S. exigua but not against the specialist P. rapae.

  19. Direct interaction between the Arabidopsis disease resistance signaling proteins, EDS1 and PAD4.

    Science.gov (United States)

    Feys, B J; Moisan, L J; Newman, M A; Parker, J E

    2001-10-01

    The Arabidopsis EDS1 and PAD4 genes encode lipase-like proteins that function in resistance (R) gene-mediated and basal plant disease resistance. Phenotypic analysis of eds1 and pad4 null mutants shows that EDS1 and PAD4 are required for resistance conditioned by the same spectrum of R genes but fulfil distinct roles within the defence pathway. EDS1 is essential for elaboration of the plant hypersensitive response, whereas EDS1 and PAD4 are both required for accumulation of the plant defence-potentiating molecule, salicylic acid. EDS1 is necessary for pathogen-induced PAD4 mRNA accumulation, whereas mutations in PAD4 or depletion of salicylic acid only partially compromise EDS1 expression. Yeast two-hybrid analysis reveals that EDS1 can dimerize and interact with PAD4. However, EDS1 dimerization is mediated by different domains to those involved in EDS1-PAD4 association. Co-immunoprecipitation experiments show that EDS1 and PAD4 proteins interact in healthy and pathogen-challenged plant cells. We propose two functions for EDS1. The first is required early in plant defence, independently of PAD4. The second recruits PAD4 in the amplification of defences, possibly by direct EDS1-PAD4 association.

  20. In silico comparison of transcript abundances during Arabidopsis thaliana and Glycine max resistance to Fusarium virguliforme

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    Iqbal M Javed

    2008-09-01

    Full Text Available Abstract Background Sudden death syndrome (SDS of soybean (Glycine max L. Merr. is an economically important disease, caused by the semi-biotrophic fungus Fusarium solani f. sp. glycines, recently renamed Fusarium virguliforme (Fv. Due to the complexity and length of the soybean-Fusarium interaction, the molecular mechanisms underlying plant resistance and susceptibility to the pathogen are not fully understood. F. virguliforme has a very wide host range for the ability to cause root rot and a very narrow host range for the ability to cause a leaf scorch. Arabidopsis thaliana is a host for many types of phytopathogens including bacteria, fungi, viruses and nematodes. Deciphering the variations among transcript abundances (TAs of functional orthologous genes of soybean and A. thaliana involved in the interaction will provide insights into plant resistance to F. viguliforme. Results In this study, we reported the analyses of microarrays measuring TA in whole plants after A. thaliana cv 'Columbia' was challenged with fungal pathogen F. virguliforme. Infection caused significant variations in TAs. The total number of increased transcripts was nearly four times more than that of decreased transcripts in abundance. A putative resistance pathway involved in responding to the pathogen infection in A. thaliana was identified and compared to that reported in soybean. Conclusion Microarray experiments allow the interrogation of tens of thousands of transcripts simultaneously and thus, the identification of plant pathways is likely to be involved in plant resistance to Fusarial pathogens. Dissection of the set functional orthologous genes between soybean and A. thaliana enabled a broad view of the functional relationships and molecular interactions among plant genes involved in F. virguliforme resistance.

  1. Sulfonamides identified as plant immune-priming compounds in high-throughput chemical screening increase disease resistance in Arabidopsis thaliana

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    Yoshiteru eNoutoshi

    2012-10-01

    Full Text Available Plant activators are agrochemicals that protect crops from diseases by activating the plant immune system. To isolate lead compounds for use as practical plant activators, we screened 2 different chemical libraries composed of various bioactive substances by using an established screening procedure that can selectively identify immune-priming compounds. We identified and characterized a group of sulfonamide compounds—sulfameter, sulfamethoxypyridazine, sulfabenzamide, and sulfachloropyridazine—among the various isolated candidate molecules. These sulfonamide compounds enhanced the avirulent Pseudomonas-induced cell death of Arabidopsis suspension cell cultures and increased disease resistance in Arabidopsis plants against both avirulent and virulent strains of the bacterium. These compounds did not prevent the growth of pathogenic bacteria in minimal liquid media at 200 µM. They also did not induce the expression of defense-related genes in Arabidopsis seedlings, at least not at 24 and 48 h after treatment, suggesting that they do not act as salicylic acid analogs. In addition, although sulfonamides are known to be folate biosynthesis inhibitors, the application of folate did not restore the potentiation effects of the sulfonamides on pathogen-induced cell death. Our data suggest that sulfonamides potentiate Arabidopsis disease resistance by their novel chemical properties.

  2. Phosphorylation of an ERF transcription factor by Arabidopsis MPK3/MPK6 regulates plant defense gene induction and fungal resistance.

    Science.gov (United States)

    Meng, Xiangzong; Xu, Juan; He, Yunxia; Yang, Kwang-Yeol; Mordorski, Breanne; Liu, Yidong; Zhang, Shuqun

    2013-03-01

    Arabidopsis thaliana MPK3 and MPK6, two mitogen-activated protein kinases (MAPKs or MPKs), play critical roles in plant disease resistance by regulating multiple defense responses. Previously, we characterized the regulation of phytoalexin biosynthesis by Arabidopsis MPK3/MPK6 cascade and its downstream WRKY33 transcription factor. Here, we report another substrate of MPK3/MPK6, ETHYLENE RESPONSE FACTOR6 (ERF6), in regulating Arabidopsis defense gene expression and resistance to the necrotrophic fungal pathogen Botrytis cinerea. Phosphorylation of ERF6 by MPK3/MPK6 in either the gain-of-function transgenic plants or in response to B. cinerea infection increases ERF6 protein stability in vivo. Phospho-mimicking ERF6 is able to constitutively activate defense-related genes, especially those related to fungal resistance, including PDF1.1 and PDF1.2, and confers enhanced resistance to B. cinerea. By contrast, expression of ERF6-EAR, in which ERF6 was fused to the ERF-associated amphiphilic repression (EAR) motif, strongly suppresses B. cinerea-induced defense gene expression, leading to hypersusceptibility of the ERF6-EAR transgenic plants to B. cinerea. Different from ERF1, the regulation and function of ERF6 in defensin gene activation is independent of ethylene. Based on these data, we conclude that ERF6, another substrate of MPK3 and MPK6, plays important roles downstream of the MPK3/MPK6 cascade in regulating plant defense against fungal pathogens.

  3. Identification of Adenyl Cyclase Activity in a Disease Resistance Protein in Arabidopsis thaliana

    KAUST Repository

    Hussein, Rana

    2012-11-01

    Cyclic nucleotide, cAMP, is an important signaling molecule in animals and plants. However, in plants the enzymes that synthesize this second messenger, adenyl cyclases (ACs), remain elusive. Given the physiological importance of cAMP in signaling, particularly in response to biotic and abiotic stresses, it is thus important to identify and characterize ACs in higher plants. Using computational approaches, a disease resistance protein from Arabidopsis thaliana, At3g04220 was found to have an AC catalytic center motif. In an attempt to prove that this candidate has adenyl cyclases activity in vitro, the coding sequence of the putative AC catalytic domain of this protein was cloned and expressed in E. coli and the recombinant protein was purified. The nucleotide cyclase activity of the recombinant protein was examined using cyclic nucleotide enzyme immunoassays. In parallel, the expression of At3g04220 was measured in leaves under three different stress conditions in order to determine under which conditions the disease resistance protein could function. Results show that the purified recombinant protein has Mn2+ dependent AC activity in vitro, and the expression analysis supports a role for At3g04220 and cAMP in plant defense.

  4. Raphanusanin-mediated resistance to pathogens is light dependent in radish and Arabidopsis thaliana.

    Science.gov (United States)

    Moehninsi; Miura, Kenji; Yamada, Kosumi; Shigemori, Hideyuki

    2014-09-01

    Raphanusanin (Ra) is a light-induced inhibitor of hypocotyl growth that responds to unilateral blue light illumination in radish seedlings. We have previously shown that Ra regulates genes that are involved in common defense mechanisms. Many genes that are induced by Ra are also positively regulated by early blue light. To extend the understanding of the role of Ra in pathogen defense, we evaluated the effects of Ra on radish and Arabidopsis thaliana (A. thaliana) infected with the necrotrophic pathogen Botrytis cinerea (B. cinerea) and biotrophic pathogen Pseudomonas syringae (P. syringae). Radish and A. thaliana were found to be resistant to both pathogens when treated with Ra, depending on the concentration used. Interestingly, Ra-mediated resistance to P. syringae is dependent on light because Ra-treated seedlings exhibited enhanced susceptibility to P. syringae infection when grown in the dark. In addition to regulating the biotic defense response, Ra inhibited seed germination and root elongation and enhanced the growth of root hairs in the presence of light in radish and A. thaliana. Our data suggest that Ra regulates the expression of a set of genes involved in defense signaling pathways and plays a role in pathogen defense and plant development. Our results show that light may be generally required not only for the accumulation of Ra but also for its activation during the pathogen defense response.

  5. Prediction of drought-resistant genes in Arabidopsis thaliana using SVM-RFE.

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    Yanchun Liang

    Full Text Available BACKGROUND: Identifying genes with essential roles in resisting environmental stress rates high in agronomic importance. Although massive DNA microarray gene expression data have been generated for plants, current computational approaches underutilize these data for studying genotype-trait relationships. Some advanced gene identification methods have been explored for human diseases, but typically these methods have not been converted into publicly available software tools and cannot be applied to plants for identifying genes with agronomic traits. METHODOLOGY: In this study, we used 22 sets of Arabidopsis thaliana gene expression data from GEO to predict the key genes involved in water tolerance. We applied an SVM-RFE (Support Vector Machine-Recursive Feature Elimination feature selection method for the prediction. To address small sample sizes, we developed a modified approach for SVM-RFE by using bootstrapping and leave-one-out cross-validation. We also expanded our study to predict genes involved in water susceptibility. CONCLUSIONS: We analyzed the top 10 genes predicted to be involved in water tolerance. Seven of them are connected to known biological processes in drought resistance. We also analyzed the top 100 genes in terms of their biological functions. Our study shows that the SVM-RFE method is a highly promising method in analyzing plant microarray data for studying genotype-phenotype relationships. The software is freely available with source code at http://ccst.jlu.edu.cn/JCSB/RFET/.

  6. Transformation of Arabidopsis thaliana via Agrobacterium tumefacience with an endochitinase gene from Trichoderma, and enhanced resistance to Sclerotinia sclerotiorum

    Institute of Scientific and Technical Information of China (English)

    DAI Fu-ming; XU Tong

    2004-01-01

    @@ Sclerotinia sclerotiorum is an important pathogen to many crops and is especially damaging to rape in China. As a model plant Arabidopsis thaliana (ColO) was transformed by spraying Agrobacterium tumefacience with Trichoderma endochitinase gene ThEn-42 at initial bud stage. Eleven seedlings (corresponding to about 0.22 percent transformation) exhibited resistance to hygromycin. The DNA fragment unique to endochitinase ( ThEn-42 ) was amplified by Arabidopsis leaf-PCR or genomic DNA PCR. Unfertile, dwarf and normal phenotypes appeared in the T1 generation. In addition, an enhanced resistance to S. sclerotiorum was observed. The mortality percentage (7.7% to 33.3%) in transgenic plants was significantly lower than in non-transgenic plants (86. 7%) 10 days after inoculation with the pathogen.

  7. UV-Induced DNA Damage Promotes Resistance to the Biotrophic Pathogen Hyaloperonospora parasitica in Arabidopsis1[C][OA

    Science.gov (United States)

    Kunz, Bernard A.; Dando, Paige K.; Grice, Desma M.; Mohr, Peter G.; Schenk, Peer M.; Cahill, David M.

    2008-01-01

    Plant innate immunity to pathogenic microorganisms is activated in response to recognition of extracellular or intracellular pathogen molecules by transmembrane receptors or resistance proteins, respectively. The defense signaling pathways share components with those involved in plant responses to UV radiation, which can induce expression of plant genes important for pathogen resistance. Such intriguing links suggest that UV treatment might activate resistance to pathogens in normally susceptible host plants. Here, we demonstrate that pre-inoculative UV (254 nm) irradiation of Arabidopsis (Arabidopsis thaliana) susceptible to infection by the biotrophic oomycete Hyaloperonospora parasitica, the causative agent of downy mildew, induces dose- and time-dependent resistance to the pathogen detectable up to 7 d after UV exposure. Limiting repair of UV photoproducts by postirradiation incubation in the dark, or mutational inactivation of cyclobutane pyrimidine dimer photolyase, (6-4) photoproduct photolyase, or nucleotide excision repair increased the magnitude of UV-induced pathogen resistance. In the absence of treatment with 254-nm UV, plant nucleotide excision repair mutants also defective for cyclobutane pyrimidine dimer or (6-4) photoproduct photolyase displayed resistance to H. parasitica, partially attributable to short wavelength UV-B (280–320 nm) radiation emitted by incubator lights. These results indicate UV irradiation can initiate the development of resistance to H. parasitica in plants normally susceptible to the pathogen and point to a key role for UV-induced DNA damage. They also suggest UV treatment can circumvent the requirement for recognition of H. parasitica molecules by Arabidopsis proteins to activate an immune response. PMID:18667719

  8. Treatment of Arabidopsis thaliana seeds with an HSP90 inhibitor increases plant resistance

    Science.gov (United States)

    Kozeko, Liudmyla

    2016-07-01

    Resistance of plants to unfavourable conditions is an important feature to use them as an autotrophic link of Life Support Systems in space exploration missions. It significantly depends on basic and stress-induced levels of heat shock proteins (HSP) in cells. It is known that HSP90 can bind and maintain heat shock transcription factors (HSF) as a monomer that lacks DNA binding activity and thereby regulate HSP expression. Modulation of activity of the HSP synthesis and resistance by HSP90 in plants is not well investigated. The objective of this study was to determine how treatment of seeds with an HSP90 inhibitor affects environmental responsiveness in Arabidopsis thaliana. Seed treatment with geldanamycin (GDA) was used to reduce HSP90 function. The affect of space flight stressors was simulated by gamma-irradiation and thermal upshift. Two series of experiments were carried out: 1) exposure of dry seeds to gamma-irradiation (1 kGy, ^{60}Co); 2) heat shock of seedlings. It was shown that GDA treatment of seeds stimulated the seedling growth after seed irradiation. It also increased both the basic thermotolerance (45°C for 45 min) and induced thermotolerance (45°C for 1,5-2,5 h after pretreatment at 37°C for 2 h) in seedlings. In addition, seed treatment with GDA had a prolonged effect on the HSP70 production in seedlings under normal and stressful conditions. It shows that the stimulatory effects of GDA may be caused by induction of HSP70 synthesis. The obtained data demonstrate that pre-treatment of seeds with GDA before planting allows inducing the stress resistance at least at early growth stages of plants.

  9. Plasmodesmata-located protein overexpression negatively impacts the manifestation of systemic acquired resistance and the long-distance movement of Defective in Induced Resistance1 in Arabidopsis.

    Science.gov (United States)

    Carella, P; Isaacs, M; Cameron, R K

    2015-03-01

    Systemic acquired resistance (SAR) is a plant defence response that provides immunity to distant uninfected leaves after an initial localised infection. The lipid transfer protein (LTP) Defective in Induced Resistance1 (DIR1) is an essential component of SAR that moves from induced to distant leaves following a SAR-inducing local infection. To understand how DIR1 is transported to distant leaves during SAR, we analysed DIR1 movement in transgenic Arabidopsis lines with reduced cell-to-cell movement caused by the overexpression of Plasmodesmata-Located Proteins PDLP1 and PDLP5. These PDLP-overexpressing lines were defective for SAR, and DIR1 antibody signals were not observed in phloem sap-enriched petiole exudates collected from distant leaves. Our data support the idea that cell-to-cell movement of DIR1 through plasmodesmata is important during long-distance SAR signalling in Arabidopsis.

  10. The Arabidopsis Mediator Complex Subunit16 Is a Key Component of Basal Resistance against the Necrotrophic Fungal Pathogen Sclerotinia sclerotiorum.

    Science.gov (United States)

    Wang, Chenggang; Yao, Jin; Du, Xuezhu; Zhang, Yanping; Sun, Yijun; Rollins, Jeffrey A; Mou, Zhonglin

    2015-09-01

    Although Sclerotinia sclerotiorum is a devastating necrotrophic fungal plant pathogen in agriculture, the virulence mechanisms utilized by S. sclerotiorum and the host defense mechanisms against this pathogen have not been fully understood. Here, we report that the Arabidopsis (Arabidopsis thaliana) Mediator complex subunit MED16 is a key component of basal resistance against S. sclerotiorum. Mutants of MED16 are markedly more susceptible to S. sclerotiorum than mutants of 13 other Mediator subunits, and med16 has a much stronger effect on S. sclerotiorum-induced transcriptome changes compared with med8, a mutation not altering susceptibility to S. sclerotiorum. Interestingly, med16 is also more susceptible to S. sclerotiorum than coronatine-insensitive1-1 (coi1-1), which is the most susceptible mutant reported so far. Although the jasmonic acid (JA)/ethylene (ET) defense pathway marker gene PLANT DEFENSIN1.2 (PDF1.2) cannot be induced in either med16 or coi1-1, basal transcript levels of PDF1.2 in med16 are significantly lower than in coi1-1. Furthermore, ET-induced suppression of JA-activated wound responses is compromised in med16, suggesting a role for MED16 in JA-ET cross talk. Additionally, MED16 is required for the recruitment of RNA polymerase II to PDF1.2 and OCTADECANOID-RESPONSIVE ARABIDOPSIS ETHYLENE/ETHYLENE-RESPONSIVE FACTOR59 (ORA59), two target genes of both JA/ET-mediated and the transcription factor WRKY33-activated defense pathways. Finally, MED16 is physically associated with WRKY33 in yeast and in planta, and WRKY33-activated transcription of PDF1.2 and ORA59 as well as resistance to S. sclerotiorum depends on MED16. Taken together, these results indicate that MED16 regulates resistance to S. sclerotiorum by governing both JA/ET-mediated and WRKY33-activated defense signaling in Arabidopsis.

  11. The Study of the Participation of Heat Shock Proteins in the Resistance to High and Low Temperatures with the Use of Thellungiella (Thellungiella salsuguinea and Transgenic Lines of Arabidopsis (Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    K.Z. Gamburg

    2017-02-01

    Full Text Available Transgenic lines of Arabidopsis with HSP101 gene in sense and anti sense orientations acquired resistance to hard heat shock (50° C 10 min or 45-47° C 1 hour and to freezing (-4° C 2 hours due to the preliminary 2 hour’s heating at 37° C. Thus, it was shown at the first time that the induction of the resistance to hard heat shock and freezing with mild heat shock is possible in the absence of HSP101 synthesis. Thellungiella with the genome to 95-97% identical to the genome of Arabidopsis did not have higher resistance to high temperature, but was significantly more resistant to freezing. It differed from Arabidopsis by several times higher contents of HSP101, HSP60 and HSC70. Contents of these HSPs in Arabidopsis increased as a result of hardening at 4° C what was accompanied by the increase of the resistance to freezing. It is supposed that the resistances to heat and cold shocks are dependent not only from HSP101, but also from other HSPs.

  12. EDS1 contributes to nonhost resistance of Arabidopsis thaliana against Erwinia amylovora.

    Science.gov (United States)

    Moreau, Manon; Degrave, Alexandre; Vedel, Régine; Bitton, Frédérique; Patrit, Oriane; Renou, Jean-Pierre; Barny, Marie-Anne; Fagard, Mathilde

    2012-03-01

    Erwinia amylovora causes fire blight in rosaceous plants. In nonhost Arabidopsis thaliana, E. amylovora triggers necrotic symptoms associated with transient bacterial multiplication, suggesting either that A. thaliana lacks a susceptibility factor or that it actively restricts E. amylovora growth. Inhibiting plant protein synthesis at the time of infection led to an increase in necrosis and bacterial multiplication and reduced callose deposition, indicating that A. thaliana requires active protein synthesis to restrict E. amylovora growth. Analysis of the callose synthase-deficient pmr4-1 mutant indicated that lack of callose deposition alone did not lead to increased sensitivity to E. amylovora. Transcriptome analysis revealed that approximately 20% of the genes induced following E. amylovora infection are related to defense and signaling. Analysis of mutants affected in NDR1 and EDS1, two main components of the defense-gene activation observed, revealed that E. amylovora multiplied ten times more in the eds1-2 mutant than in the wild type but not in the ndr1-1 mutant. Analysis of mutants affected in three WRKY transcription factors showing EDS1-dependent activation identified WRKY46 and WRKY54 as positive regulators and WRKY70 as a negative regulator of defense against E. amylovora. Altogether, we show that EDS1 is a positive regulator of nonhost resistance against E. amylovora in A. thaliana and hypothesize that it controls the production of several effective defenses against E. amylovora through the action of WRKY46 and WRKY54, while WRKY70 acts as a negative regulator.

  13. Water-soluble chlorophyll protein is involved in herbivore resistance activation during greening of Arabidopsis thaliana

    Science.gov (United States)

    Boex-Fontvieille, Edouard; Rustgi, Sachin; von Wettstein, Diter; Reinbothe, Steffen; Reinbothe, Christiane

    2015-01-01

    Water-soluble chlorophyll proteins (WSCPs) constitute a small family of unusual chlorophyll (Chl)-binding proteins that possess a Kunitz-type protease inhibitor domain. In Arabidopsis thaliana, a WSCP has been identified, named AtWSCP, that forms complexes with Chl and the Chl precursor chlorophyllide (Chlide) in vitro. AtWSCP exhibits a quite unexpected expression pattern for a Chl binding protein and accumulated to high levels in the apical hook of etiolated plants. AtWSCP expression was negatively light-regulated. Transgenic expression of AtWSCP fused to green fluorescent protein (GFP) revealed that AtWSCP is localized to cell walls/apoplastic spaces. Biochemical assays identified AtWSCP as interacting with RD21 (RESPONSIVE TO DESICCATION 21), a granulin domain-containing cysteine protease implicated in stress responses and defense. Reconstitution experiments showed tight interactions between RD21 and WSCP that were relieved upon Chlide binding. Laboratory feeding experiments with two herbivorous isopod crustaceans, Porcellio scaber (woodlouse) and Armadillidium vulgare (pillbug), identified the apical hook as Achilles’ heel of etiolated plants and that this was protected by RD21 during greening. Because Chlide is formed in the apical hook during seedling emergence from the soil, our data suggest an unprecedented mechanism of herbivore resistance activation that is triggered by light and involves AtWSCP. PMID:26016527

  14. The carrier AUXIN RESISTANT (AUX1) dominates auxin flux into Arabidopsis protoplasts.

    Science.gov (United States)

    Rutschow, Heidi L; Baskin, Tobias I; Kramer, Eric M

    2014-11-01

    The ability of the plant hormone auxin to enter a cell is critical to auxin transport and signaling. Auxin can cross the cell membrane by diffusion or via auxin-specific influx carriers. There is little knowledge of the magnitudes of these fluxes in plants. Radiolabeled auxin uptake was measured in protoplasts isolated from roots of Arabidopsis thaliana. This was done for the wild-type, under treatments with additional unlabeled auxin to saturate the influx carriers, and for the influx carrier mutant auxin resistant 1 (aux1). We also used flow cytometry to quantify the relative abundance of cells expressing AUX1-YFP in the assayed population. At pH 5.7, the majority of auxin influx into protoplasts - 75% - was mediated by the influx carrier AUX1. An additional 20% was mediated by other saturable carriers. The diffusive influx of auxin was essentially negligible at pH 5.7. The influx of auxin mediated by AUX1, expressed as a membrane permeability, was 1.5 ± 0.3 μm s(-1) . This value is comparable in magnitude to estimates of efflux permeability. Thus, auxin-transporting tissues can sustain relatively high auxin efflux and yet not become depleted of auxin.

  15. Loss of actin cytoskeletal function and EDS1 activity, in combination, severely compromises non-host resistance in Arabidopsis against wheat powdery mildew.

    Science.gov (United States)

    Yun, Byung-Wook; Atkinson, Helen A; Gaborit, Charlotte; Greenland, Andy; Read, Nick D; Pallas, Jacqueline A; Loake, Gary J

    2003-06-01

    Plant immunity against the majority of the microbial pathogens is conveyed by a phenomenon known as non-host resistance (NHR). This defence mechanism affords durable protection to plant species against given species of phytopathogens. We investigated the genetic basis of NHR in Arabidopsis against the wheat powdery mildew fungus Blumeria graminis f. sp. tritici (Bgt). Both primary and appressorial germ tubes were produced from individual Bgt conidia on the surface of the Arabidopsis leaves. Attempted infection occasionally resulted in successful penetration, which led to the development of an abnormal unilateral haustorium. Inoculation of a series of Arabidopsis defence-related mutants with Bgt resulted in the attenuation of reactive oxygen intermediate (ROI) production and salicylic acid (SA)-dependent defence gene expression in eds1, pad4 and nahG plants, which are known to be defective in some aspects of host resistance. Furthermore, Bgt often developed bilateral haustoria in the mutant Arabidopsis lines that closely resembled those formed in wheat. A similar decrease in NHR was observed following treatment of the wild-type Arabidopsis plants with cytochalasin E, an inhibitor of actin microfilament polymerisation. In eds1 mutants, inhibition of actin polymerisation severely compromised NHR in Arabidopsis against Bgt. This permitted completion of the Bgt infection cycle on these plants. Therefore, actin cytoskeletal function and EDS1 activity, in combination, are major contributors to NHR in Arabidopsis against wheat powdery mildew.

  16. Arabidopsis WRKY33 transcription factor is required for resistance to necrotrophic fungal pathogens.

    Science.gov (United States)

    Zheng, Zuyu; Qamar, Synan Abu; Chen, Zhixiang; Mengiste, Tesfaye

    2006-11-01

    Plant WRKY transcription factors are key regulatory components of plant responses to microbial infection. In addition to regulating the expression of defense-related genes, WRKY transcription factors have also been shown to regulate cross-talk between jasmonate- and salicylate-regulated disease response pathways. The two pathways mediate resistance against different types of microbial pathogens, and there are numerous reports of antagonistic interactions between them. Here we show that mutations of the Arabidopsis WRKY33 gene encoding a WRKY transcription factor cause enhanced susceptibility to the necrotrophic fungal pathogens Botrytis cinerea and Alternaria brassicicola concomitant with reduced expression of the jasmonate-regulated plant defensin PDF1.2 gene. Ectopic over-expression of WRKY33, on the other hand, increases resistance to the two necrotrophic fungal pathogens. The wrky33 mutants do not show altered responses to a virulent strain of the bacterial pathogen Pseudomonas syringae, although the ectopic expression of WRKY33 results in enhanced susceptibility to this pathogen. The susceptibility of WRKY33-over-expressing plants to P. syringae is associated with reduced expression of the salicylate-regulated PR-1 gene. The WRKY33 transcript is induced in response to pathogen infection, or treatment with salicylate or the paraquat herbicide that generates activated oxygen species in exposed cells. WRKY33 is localized to the nucleus of plant cells and recognizes DNA molecules containing the TTGACC W-box sequence. Together, these results indicate that pathogen-induced WRKY33 is an important transcription factor that regulates the antagonistic relationship between defense pathways mediating responses to P. syringae and necrotrophic pathogens.

  17. Arabidopsis flower specific defense gene expression patterns affect resistance to pathogens

    KAUST Repository

    Ederli, Luisa

    2015-02-20

    We investigated whether the Arabidopsis flower evolved protective measures to increase reproductive success. Firstly, analyses of available transcriptome data show that the most highly expressed transcripts in the closed sepal (stage 12) are enriched in genes with roles in responses to chemical stimuli and cellular metabolic processes. At stage 15, there is enrichment in transcripts with a role in responses to biotic stimuli. Comparative analyses between the sepal and petal in the open flower mark an over-representation of transcripts with a role in responses to stress and catalytic activity. Secondly, the content of the biotic defense-associated phytohormone salicylic acid (SA) in sepals and petals is significantly higher than in leaves. To understand whether the high levels of stress responsive transcripts and the higher SA content affect defense, wild-type plants (Col-0) and transgenic plants defective in SA accumulation (nahG) were challenged with the biotrophic fungus Golovinomyces cichoracearum, the causal agent of powdery mildew, and the necrotrophic fungus Botrytis cinerea. NahG leaves were more sensitive than those of Col-0, suggesting that in leaves SA has a role in the defense against biotrophs. In contrast, sepals and petals of both genotypes were resistant to G. cichoracearum, indicating that in the flower, resistance to the biotrophic pathogen is not critically dependent on SA, but likely dependent on the up-regulation of stress-responsive genes. Since sepals and petals of both genotypes are equally susceptible to B. cinerea, we conclude that neither stress-response genes nor increased SA accumulation offers protection against the necrotrophic pathogen. These results are interpreted in the light of the distinctive role of the flower and we propose that in the early stages, the sepal may act as a chemical defense barrier of the developing reproductive structures against biotrophic pathogens.

  18. ZmPep1, an ortholog of Arabidopsis elicitor peptide 1, regulates maize innate immunity and enhances disease resistance.

    Science.gov (United States)

    Huffaker, Alisa; Dafoe, Nicole J; Schmelz, Eric A

    2011-03-01

    ZmPep1 is a bioactive peptide encoded by a previously uncharacterized maize (Zea mays) gene, ZmPROPEP1. ZmPROPEP1 was identified by sequence similarity as an ortholog of the Arabidopsis (Arabidopsis thaliana) AtPROPEP1 gene, which encodes the precursor protein of elicitor peptide 1 (AtPep1). Together with its receptors, AtPEPR1 and AtPEPR2, AtPep1 functions to activate and amplify innate immune responses in Arabidopsis and enhances resistance to both Pythium irregulare and Pseudomonas syringae. Candidate orthologs to the AtPROPEP1 gene have been identified from a variety of crop species; however, prior to this study, activities of the respective peptides encoded by these orthologs were unknown. Expression of the ZmPROPEP1 gene is induced by fungal infection and treatment with jasmonic acid or ZmPep1. ZmPep1 activates de novo synthesis of the hormones jasmonic acid and ethylene and induces the expression of genes encoding the defense proteins endochitinase A, PR-4, PRms, and SerPIN. ZmPep1 also stimulates the expression of Benzoxazineless1, a gene required for the biosynthesis of benzoxazinoid defenses, and the accumulation of 2-hydroxy-4,7-dimethoxy-1,4-benzoxazin-3-one glucoside in leaves. To ascertain whether ZmPep1-induced defenses affect resistance, maize plants were pretreated with the peptide prior to infection with fungal pathogens. Based on cell death and lesion severity, ZmPep1 pretreatment was found to enhance resistance to both southern leaf blight and anthracnose stalk rot caused by Cochliobolis heterostrophus and Colletotrichum graminicola, respectively. We present evidence that peptides belonging to the Pep family have a conserved function across plant species as endogenous regulators of innate immunity and may have potential for enhancing disease resistance in crops.

  19. AtMYB44 regulates resistance to the green peach aphid and diamondback moth by activating EIN2-affected defences in Arabidopsis.

    Science.gov (United States)

    Lü, B-B; Li, X-J; Sun, W-W; Li, L; Gao, R; Zhu, Q; Tian, S-M; Fu, M-Q; Yu, H-L; Tang, X-M; Zhang, C-L; Dong, H-S

    2013-09-01

    Recently we showed that the transcription activator AtMYB44 regulates expression of EIN2, a gene essential for ethylene signalling and insect resistance, in Arabidopsis thaliana (Arabidopsis). To link the transactivation with insect resistance, we investigated the wild-type and atmyb44 mutant plants, genetically Complemented atmyb44 (Catmyb44) and AtMYB44-Overexpression Transgenic Arabidopsis (MYB44OTA). We found that AtMYB44 played a critical role in Arabidopsis resistance to the phloem-feeding generalist green peach aphid (Myzus persicae Sulzer) and leaf-chewing specialist caterpillar diamondback moth (Plutella xylostella L.). AtMYB44 was required not only for the development of constitutive resistance but also for the induction of resistance by both herbivorous insects. Levels of constitutive and herbivore-induced resistance were consistent with corresponding amounts of the AtMYB44 protein constitutively produced in MYB44OTA and induced by herbivory in Catmyb44. In both cases, AtMYB44 promoted EIN2 expression to a greater extent in MYB44OTA than in Catmyb44. However, AtMYB44-promoted EIN2 expression was arrested with reduced resistance levels in the EIN2-deficient Arabidopsis mutant ein2-1 and the MYB44OTA ein2-1 hybrid. In the different plant genotypes, only MYB44OTA constitutively displayed phloem-based defences, which are specific to phloem-feeding insects, and robust expression of genes involved in the biosynthesis of glucosinolates, which are the secondary plant metabolites known as deterrents to generalist herbivores. Phloem-based defences and glucosinolate-related gene expression were not detected in ein2-1 and MYB44OTA ein2-1. These results establish a genetic connection between the regulatory role of AtMYB44 in EIN2 expression and the development of Arabidopsis resistance to insects.

  20. Two seven-transmembrane domain MILDEW RESISTANCE LOCUS O proteins cofunction in Arabidopsis root thigmomorphogenesis.

    Science.gov (United States)

    Chen, Zhongying; Noir, Sandra; Kwaaitaal, Mark; Hartmann, H Andreas; Wu, Ming-Jing; Mudgil, Yashwanti; Sukumar, Poornima; Muday, Gloria; Panstruga, Ralph; Jones, Alan M

    2009-07-01

    Directional root expansion is governed by nutrient gradients, positive gravitropism and hydrotropism, negative phototropism and thigmotropism, as well as endogenous oscillations in the growth trajectory (circumnutation). Null mutations in phylogenetically related Arabidopsis thaliana genes MILDEW RESISTANCE LOCUS O 4 (MLO4) and MLO11, encoding heptahelical, plasma membrane-localized proteins predominantly expressed in the root tip, result in aberrant root thigmomorphogenesis. mlo4 and mlo11 mutant plants show anisotropic, chiral root expansion manifesting as tightly curled root patterns upon contact with solid surfaces. The defect in mlo4 and mlo11 mutants is nonadditive and dependent on light and nutrients. Genetic epistasis experiments demonstrate that the mutant phenotype is independently modulated by the Gbeta subunit of the heterotrimeric G-protein complex. Analysis of expressed chimeric MLO4/MLO2 proteins revealed that the C-terminal domain of MLO4 is necessary but not sufficient for MLO4 action in root thigmomorphogenesis. The expression of the auxin efflux carrier fusion, PIN1-green fluorescent protein, the pattern of auxin-induced gene expression, and acropetal as well as basipetal auxin transport are altered at the root tip of mlo4 mutant seedlings. Moreover, addition of auxin transport inhibitors or the loss of EIR1/AGR1/PIN2 function abolishes root curling of mlo4, mlo11, and wild-type seedlings. These results demonstrate that the exaggerated root curling phenotypes of the mlo4 and mlo11 mutants depend on auxin gradients and suggest that MLO4 and MLO11 cofunction as modulators of touch-induced root tropism.

  1. Constitutive production of nitric oxide leads to enhanced drought stress resistance and extensive transcriptional reprogramming in Arabidopsis.

    Science.gov (United States)

    Shi, Haitao; Ye, Tiantian; Zhu, Jian-Kang; Chan, Zhulong

    2014-08-01

    Nitric oxide (NO) is involved in plant responses to many environmental stresses. Transgenic Arabidopsis lines that constitutively express rat neuronal NO synthase (nNOS) were described recently. In this study, it is reported that the nNOS transgenic Arabidopsis plants displayed high levels of osmolytes and increased antioxidant enzyme activities. Transcriptomic analysis identified 601 or 510 genes that were differentially expressed as a consequence of drought stress or nNOS transformation, respectively. Pathway and gene ontology (GO) term enrichment analyses revealed that genes involved in photosynthesis, redox, stress, and phytohormone and secondary metabolism were greatly affected by the nNOS transgene. Several CBF genes and members of zinc finger gene families, which are known to regulate transcription in the stress response, were changed by the nNOS transgene. Genes regulated by both the nNOS transgene and abscisic acid (ABA) treatments were compared and identified, including those for two ABA receptors (AtPYL4 and AtPYL5). Moreover, overexpression of AtPYL4 and AtPYL5 enhanced drought resistance, antioxidant enzyme activity, and osmolyte levels. These observations increase our understanding of the role of NO in drought stress response in Arabidopsis.

  2. Pathogen-associated molecular pattern-triggered immunity and resistance to the root pathogen Phytophthora parasitica in Arabidopsis.

    Science.gov (United States)

    Larroque, Mathieu; Belmas, Elodie; Martinez, Thomas; Vergnes, Sophie; Ladouce, Nathalie; Lafitte, Claude; Gaulin, Elodie; Dumas, Bernard

    2013-09-01

    The cellulose binding elicitor lectin (CBEL) of the genus Phytophthora induces necrosis and immune responses in several plant species, including Arabidopsis thaliana. However, the role of CBEL-induced responses in the outcome of the interaction is still unclear. This study shows that some of CBEL-induced defence responses, but not necrosis, required the receptor-like kinase BAK1, a general regulator of basal immunity in Arabidopsis, and the production of a reactive oxygen burst mediated by respiratory burst oxidases homologues (RBOH). Screening of a core collection of 48 Arabidopsis ecotypes using CBEL uncovered a large variability in CBEL-induced necrotic responses. Analysis of non-responsive CBEL lines Ws-4, Oy-0, and Bla-1 revealed that Ws-4 and Oy-0 were also impaired in the production of the oxidative burst and expression of defence genes, whereas Bla-1 was partially affected in these responses. Infection tests using two Phytophthora parasitica strains, Pp310 and Ppn0, virulent and avirulent, respectively, on the Col-0 line showed that BAK1 and RBOH mutants were susceptible to Ppn0, suggesting that some immune responses controlled by these genes, but not CBEL-induced cell death, are required for Phytophthora parasitica resistance. However, Ws-4, Oy-0, and Bla-1 lines were not affected in Ppn0 resistance, showing that natural variability in CBEL responsiveness is not correlated to Phytophthora susceptibility. Overall, the results uncover a BAK1- and RBOH-dependent CBEL-triggered immunity essential for Phytophthora resistance and suggest that natural quantitative variation of basal immunity triggered by conserved general elicitors such as CBEL does not correlate to Phytophthora susceptibility.

  3. Moss Pathogenesis-Related-10 Protein Enhances Resistance to Pythium irregulare in Physcomitrella patens and Arabidopsis thaliana.

    Science.gov (United States)

    Castro, Alexandra; Vidal, Sabina; Ponce de León, Inés

    2016-01-01

    Plants respond to pathogen infection by activating signaling pathways leading to the accumulation of proteins with diverse roles in defense. Here, we addressed the functional role of PpPR-10, a pathogenesis-related (PR)-10 gene, of the moss Physcomitrella patens, in response to biotic stress. PpPR-10 belongs to a multigene family and encodes a protein twice the usual size of PR-10 proteins due to the presence of two Bet v1 domains. Moss PR-10 genes are differentially regulated during development and inoculation with the fungal pathogen Botrytis cinerea. Specifically, PpPR-10 transcript levels increase significantly by treatments with elicitors of Pectobacterium carotovorum subsp. carotovorum, spores of B. cinerea, and the defense hormone salicylic acid. To characterize the role of PpPR-10 in plant defense against pathogens, we conducted overexpression analysis in P. patens and in Arabidopsis thaliana. We demonstrate that constitutive expression of PpPR-10 in moss tissues increased resistance against the oomycete Pythium irregulare. PpPR-10 overexpressing moss plants developed less symptoms and decreased mycelium growth than wild type plants. In addition, PpPR-10 overexpressing plants constitutively produced cell wall depositions in protonemal tissue. Ectopic expression of PpPR-10 in Arabidopsis resulted in increased resistance against P. irregulare as well, evidenced by smaller lesions and less cellular damage compared to wild type plants. These results indicate that PpPR-10 is functionally active in the defense against the pathogen P. irregulare, in both P. patens and Arabidopsis, two evolutionary distant plants. Thus, P. patens can serve as an interesting source of genes to improve resistance against pathogen infection in flowering plants.

  4. Moss Pathogenesis-Related-10 protein enhances resistance to Pythium irregulare in Physcomitrella patens and Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Alexandra eCastro

    2016-04-01

    Full Text Available Plants respond to pathogen infection by activating signaling pathways leading to the accumulation of proteins with diverse roles in defense. Here, we addressed the functional role of PpPR-10, a pathogenesis-related (PR-10 gene, of the moss Physcomitrella patens, in response to biotic stress. PpPR-10 belongs to a multigene family and encodes a protein twice the usual size of PR-10 proteins due to the presence of two Bet v1 domains. Moss PR-10 genes are differentially regulated during development and inoculation with the fungal pathogen Botrytis cinerea. Specifically, PpPR-10 transcript levels increase significantly by treatments with elicitors of Pectobacterium carotovorum subsp. carotovorum, spores of B. cinerea, and the defense hormone salicylic acid. To characterize the role of PpPR-10 in plant defense against pathogens, we conducted overexpression analysis in P. patens and in Arabidopsis thaliana. We demonstrate that constitutive expression of PpPR-10 in moss tissues increased resistance against the oomycete Pythium irregulare. PpPR-10 overexpressing moss plants developed less symptoms and decreased mycelium growth than wild type plants. In addition, PpPR-10 overexpressing plants constitutively produced cell wall depositions in protonemal tissue. Ectopic expression of PpPR-10 in Arabidopsis resulted in increased resistance against P. irregulare as well, evidenced by smaller lesions and less cellular damage compared to wild type plants. These results indicate that PpPR-10 is functionally active in the defense against the pathogen P. irregulare, in both P. patens and Arabidopsis, two evolutionary distant plants. Thus, P. patens can serve as an interesting source of genes to improve resistance against pathogen infection in flowering plants.

  5. Evidence for a positive regulatory role of strawberry (Fragaria x ananassa) Fa WRKY1 and Arabidopsis At WRKY75 proteins in resistance.

    Science.gov (United States)

    Encinas-Villarejo, Sonia; Maldonado, Ana M; Amil-Ruiz, Francisco; de los Santos, Berta; Romero, Fernando; Pliego-Alfaro, Fernando; Muñoz-Blanco, Juan; Caballero, José L

    2009-01-01

    Knowledge of the molecular basis of plant resistance to pathogens in species other than Arabidopsis is limited. The function of Fa WRKY1, the first WRKY gene isolated from strawberry (Fragaria x ananassa), an important agronomical fruit crop, has been investigated here. Fa WRKY1 encodes a IIc WRKY transcription factor and is up-regulated in strawberry following Colletotrichum acutatum infection, treatments with elicitors, and wounding. Its Arabidopsis sequence homologue, At WRKY75, has been described as playing a role in regulating phosphate starvation responses. However, using T-DNA insertion mutants, a role for the At WRKY75 and Fa WRKY1 in the activation of basal and R-mediated resistance in Arabidopsis is demonstrated. At wrky75 mutants are more susceptible to virulent and avirulent isolates of Pseudomonas syringae. Overexpression of Fa WRKY1 in At wrky75 mutant and wild type reverts the enhanced susceptible phenotype of the mutant, and even increases resistance to avirulent strains of P. syringae. The resistance phenotype is uncoupled to PATHOGENESIS-RELATED (PR) gene expression, but it is associated with a strong oxidative burst and glutathione-S-transferase (GST) induction. Taken together, these results indicate that At WRKY75 and Fa WRKY1 act as positive regulators of defence during compatible and incompatible interactions in Arabidopsis and, very likely, Fa WRKY1 is an important element mediating defence responses to C. acutatum in strawberry. Moreover, these results provide evidence that Arabidopsis can be a useful model for functional studies in Rosacea species like strawberry.

  6. Overexpression of a novel Arabidopsis gene related to putative zinc-transporter genes from animals can lead to enhanced zinc resistance and accumulation.

    Science.gov (United States)

    van der Zaal, B J; Neuteboom, L W; Pinas, J E; Chardonnens, A N; Schat, H; Verkleij, J A; Hooykaas, P J

    1999-03-01

    We describe the isolation of an Arabidopsis gene that is closely related to the animal ZnT genes (Zn transporter). The protein encoded by the ZAT (Zn transporter of Arabidopsis thaliana) gene has 398 amino acid residues and is predicted to have six membrane-spanning domains. To obtain evidence for the postulated function of the Arabidopsis gene, transgenic plants with the ZAT coding sequence under control of the cauliflower mosaic virus 35S promoter were analyzed. Plants obtained with ZAT in the sense orientation exhibited enhanced Zn resistance and strongly increased Zn content in the roots under high Zn exposure. Antisense mRNA-producing plants were viable, with a wild-type level of Zn resistance and content, like plants expressing a truncated coding sequence lacking the C-terminal cytoplasmic domain of the protein. The availability of ZAT can lead to a better understanding of the mechanism of Zn homeostasis and resistance in plants.

  7. Foliar treatments with Gaultheria procumbens essential oil induce defence responses and resistance against a fungal pathogen in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Sophie eVergnes

    2014-09-01

    Full Text Available Essential oil from Gaultheria procumbens is mainly composed of methylsalicylate (>96%, a compound which can be metabolized in plant tissues to salicylic acid, a phytohormone inducing plant immunity against microbial pathogens. The potential use of G. procumbens essential oil as a biocontrol agent was evaluated on the model plant Arabidopsis thaliana. Expression of a selection of defence genes was detected 1, 6 and 24 hours after essential oil treatment (0.1 ml/L using a high-throughput qPCR-based microfluidic technology. Control treatments included methyl jasmonate and a commercialized salicylic acid analog, benzo(1,2,3-thiadiazole-7carbothiolic acid (BTH. Strong induction of defence markers known to be regulated by the salicylic acid pathway was observed after the treatment with G. procumbens essential oil. Treatment induced the accumulation of total salicylic acid in the wild -type Arabidopsis line Col-0 and analysis of the Arabidopsis line sid2, mutated in a salicylic acid biosynthetic gene, revealed that approximately 30% of methylsalicylate sprayed on the leaves penetrated inside plant tissues and was demethylated by endogenous esterases. Induction of plant resistance by G. procumbens essential oil was tested following inoculation with a GFP-expressing strain of the Arabidopsis fungal pathogen Colletotrichum higginsianum. Flurorescence measurement of infected tissues revealed that treatments led to a strong reduction (60% of pathogen development and that the efficacy of the G. procumbens essential oil was similar to the commercial product BION®. Together, these results show that the G. procubens essential oil is a natural source of methylsalicylate which can be formulated to develop new biocontrol products.

  8. Benzoylsalicylic acid isolated from seed coats of Givotia rottleriformis induces systemic acquired resistance in tobacco and Arabidopsis.

    Science.gov (United States)

    Kamatham, Samuel; Neela, Kishore Babu; Pasupulati, Anil Kumar; Pallu, Reddanna; Singh, Surya Satyanarayana; Gudipalli, Padmaja

    2016-06-01

    Systemic acquired resistance (SAR), a whole plant defense response to a broad spectrum of pathogens, is characterized by a coordinated expression of a large number of defense genes. Plants synthesize a variety of secondary metabolites to protect themselves from the invading microbial pathogens. Several studies have shown that salicylic acid (SA) is a key endogenous component of local and systemic disease resistance in plants. Although SA is a critical signal for SAR, accumulation of endogenous SA levels alone is insufficient to establish SAR. Here, we have identified a new acyl derivative of SA, the benzoylsalicylic acid (BzSA) also known as 2-(benzoyloxy) benzoic acid from the seed coats of Givotia rottleriformis and investigated its role in inducing SAR in tobacco and Arabidopsis. Interestingly, exogenous BzSA treatment induced the expression of NPR1 (Non-expressor of pathogenesis-related gene-1) and pathogenesis related (PR) genes. BzSA enhanced the expression of hypersensitivity related (HSR), mitogen activated protein kinase (MAPK) and WRKY genes in tobacco. Moreover, Arabidopsis NahG plants that were treated with BzSA showed enhanced resistance to tobacco mosaic virus (TMV) as evidenced by reduced leaf necrosis and TMV-coat protein levels in systemic leaves. We, therefore, conclude that BzSA, hitherto unknown natural plant product, is a new SAR inducer in plants.

  9. Is the cost of herbicide resistance expressed in the breakdown of the relationships between characters? A case study using synthetic-auxin-resistant Arabidopsis thaliana mutants.

    Science.gov (United States)

    Roux, Fabrice; Reboud, Xavier

    2005-04-01

    A mutation endowing herbicide resistance is often found to induce a parallel morphological or fitness penalty. To test whether such 'cost' of resistance to herbicides is expressed through lower resource acquisition, changes in resource allocation, or both, is of ecological significance. Here, we analysed 12 morphological traits in 900 plants covering three herbicide resistance mutations at genes AUX1 , AXR1 and AXR2 in the model species Arabidopsis thaliana . Comparing these 2,4-D herbicide-resistant homozygous (RR) and heterozygous (RS) plants to homozygous susceptible (SS) plants, this analysis estimates the dominance level of the resistance allele on morphology. We also demonstrated that the herbicide resistance cost was primarily expressed as a change in resource acquisition (62.1-94% of the analysed traits). Although AUX1 , AXR1 and AXR2 genes act in the same metabolic pathway of auxin response, each resistance factor was found to have its own unique signature in the way the cost was expressed. Furthermore, no link was observed between the absolute fitness penalty and the respective modifications of resource acquisition and/or resource allocation in the resistant plants. These results and their implications for herbicide resistance spread and establishment are discussed.

  10. Arabidopsis nonhost resistance gene PSS1 confers immunity against an oomycete and a fungal pathogen but not a bacterial pathogen that cause diseases in soybean

    Directory of Open Access Journals (Sweden)

    Sumit Rishi

    2012-06-01

    Full Text Available Abstract Background Nonhost resistance (NHR provides immunity to all members of a plant species against all isolates of a microorganism that is pathogenic to other plant species. Three Arabidopsis thaliana PEN (penetration deficient genes, PEN1, 2 and 3 have been shown to provide NHR against the barley pathogen Blumeria graminis f. sp. hordei at the prehaustorial level. Arabidopsis pen1-1 mutant lacking the PEN1 gene is penetrated by the hemibiotrophic oomycete pathogen Phytophthora sojae, the causal organism of the root and stem rot disease in soybean. We investigated if there is any novel nonhost resistance mechanism in Arabidopsis against the soybean pathogen, P. sojae. Results The P.sojaesusceptible (pss 1 mutant was identified by screening a mutant population created in the Arabidopsis pen1-1 mutant that lacks penetration resistance against the non adapted barley biotrophic fungal pathogen, Blumeria graminis f. sp. hordei. Segregation data suggested that PEN1 is not epistatic to PSS1. Responses of pss1 and pen1-1 to P. sojae invasion were distinct and suggest that PSS1 may act at both pre- and post-haustorial levels, while PEN1 acts at the pre-haustorial level against this soybean pathogen. Therefore, PSS1 encodes a new form of nonhost resistance. The pss1 mutant is also infected by the necrotrophic fungal pathogen, Fusarium virguliforme, which causes sudden death syndrome in soybean. Thus, a common NHR mechanism is operative in Arabidopsis against both hemibiotrophic oomycetes and necrotrophic fungal pathogens that are pathogenic to soybean. However, PSS1 does not play any role in immunity against the bacterial pathogen, Pseudomonas syringae pv. glycinea, that causes bacterial blight in soybean. We mapped PSS1 to a region very close to the southern telomere of chromosome 3 that carries no known disease resistance genes. Conclusions The study revealed that Arabidopsis PSS1 is a novel nonhost resistance gene that confers a new form of

  11. Rhizobacteria-mediated induced systemic resistance (ISR) in Arabidopsis is not associated with a direct effect on expression of known defense-related genes but stimulates the expression of the jasmonate-inducible gene Atvsp upon challenge

    NARCIS (Netherlands)

    Wees, A.C.M. van; Luijendijk, M.; Smoorenburg, I.; Loon, L.C. van; Pieterse, C.M.J.

    1999-01-01

    Selected strains of nonpathogenic rhizobacteria from the genus Pseudomonas are capable of eliciting broadspectrum induced systemic resistance (ISR) in plants that is phenotypically similar to pathogen-induced systemic acquired resistance (SAR). In Arabidopsis, the ISR pathway functions independently

  12. Characterization of eds1, a mutation in Arabidopsis suppressing resistance to Peronospora parasitica specified by several different RPP genes.

    Science.gov (United States)

    Parker, J E; Holub, E B; Frost, L N; Falk, A; Gunn, N D; Daniels, M J

    1996-11-01

    The interaction between Arabidopsis and the biotrophic oomycete Peronospora parasitica (downy mildew) provides an attractive model pathosystem to identify molecular components of the host that are required for genotype-specific recognition of the parasite. These components are the so-called RPP genes (for resistance to P. parasitica). Mutational analysis of the ecotype Wassilewskija (Ws-0) revealed an RPP-nonspecific locus called EDS1 (for enhanced disease susceptibility) that is required for the function of RPP genes on chromosomes 3 (RPP1/RPP14 and RPP10) and 4 (RPP12). Genetic analyses demonstrated that the eds1 mutation is recessive and is not a defective allele of any known RPP gene, mapping to the bottom arm of chromosome 3 (approximately 13 centimorgans below RPP1/RPP14). Phenotypically, the Ws-eds1 mutant seedlings supported heavy sporulation by P. parasitica isolates that are each diagnostic for one of the RPP genes in wild-type Ws-0; none of the isolates is capable of sporulating on wild-type Ws-0. Ws-eds1 seedlings exhibited enhanced susceptibility to some P. parasitica isolates when compared with a compatible wild-type ecotype, Columbia, and the eds1 parental ecotype, Ws-0. This was observed as earlier initiation of sporulation and elevated production of conidiosporangia. Surprisingly, cotyledons of Ws-eds1 also supported low sporulation by five isolates of P. parasitica from Brassica oleracea. These isolates were unable to sporulate on > 100 ecotypes of Arabidopsis, including wild-type Ws-0. An isolate of Albugo candida (white blister) from B. oleracea also sporulated on Ws-eds1, but the mutant exhibited no alteration in phenotype when inoculated with several oomycete isolates from other host species. The bacterial resistance gene RPM1, conferring specific recognition of the avirulence gene avrB from Pseudomonas syringae pv glycinea, was not compromised in Ws-eds1 plants. The mutant also retained full responsiveness to the chemical inducer of systemic

  13. Functional properties of a cysteine proteinase from pineapple fruit with improved resistance to fungal pathogens in Arabidopsis thaliana.

    Science.gov (United States)

    Wang, Wei; Zhang, Lu; Guo, Ning; Zhang, Xiumei; Zhang, Chen; Sun, Guangming; Xie, Jianghui

    2014-01-01

    In plant cells, many cysteine proteinases (CPs) are synthesized as precursors in the endoplasmic reticulum, and then are subject to post-translational modifications to form the active mature proteinases. They participate in various cellular and physiological functions. Here, AcCP2, a CP from pineapple fruit (Ananas comosus L.) belonging to the C1A subfamily is analyzed based on the molecular modeling and homology alignment. Transcripts of AcCP2 can be detected in the different parts of fruits (particularly outer sarcocarps), and gradually increased during fruit development until maturity. To analyze the substrate specificity of AcCP2, the recombinant protein was overexpressed and purified from Pichia pastoris. The precursor of purified AcCP2 can be processed to a 25 kDa active form after acid treatment (pH 4.3). Its optimum proteolytic activity to Bz-Phe-Val-Arg-NH-Mec is at neutral pH. In addition, the overexpression of AcCP2 gene in Arabidopsis thaliana can improve the resistance to fungal pathogen of Botrytis cinerea. These data indicate that AcCP2 is a multifunctional proteinase, and its expression could cause fruit developmental characteristics of pineapple and resistance responses in transgenic Arabidopsis plants.

  14. Functional Properties of a Cysteine Proteinase from Pineapple Fruit with Improved Resistance to Fungal Pathogens in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Wei Wang

    2014-02-01

    Full Text Available In plant cells, many cysteine proteinases (CPs are synthesized as precursors in the endoplasmic reticulum, and then are subject to post-translational modifications to form the active mature proteinases. They participate in various cellular and physiological functions. Here, AcCP2, a CP from pineapple fruit (Ananas comosus L. belonging to the C1A subfamily is analyzed based on the molecular modeling and homology alignment. Transcripts of AcCP2 can be detected in the different parts of fruits (particularly outer sarcocarps, and gradually increased during fruit development until maturity. To analyze the substrate specificity of AcCP2, the recombinant protein was overexpressed and purified from Pichia pastoris. The precursor of purified AcCP2 can be processed to a 25 kDa active form after acid treatment (pH 4.3. Its optimum proteolytic activity to Bz-Phe-Val-Arg-NH-Mec is at neutral pH. In addition, the overexpression of AcCP2 gene in Arabidopsis thaliana can improve the resistance to fungal pathogen of Botrytis cinerea. These data indicate that AcCP2 is a multifunctional proteinase, and its expression could cause fruit developmental characteristics of pineapple and resistance responses in transgenic Arabidopsis plants.

  15. Molecular and Functional Characterization of a Polygalacturonase-Inhibiting Protein from Cynanchum komarovii That Confers Fungal Resistance in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Nana Liu

    Full Text Available Compliance with ethical standards: This study did not involve human participants and animals, and the plant of interest is not an endangered species. Polygalacturonase-inhibiting proteins (PGIPs are leucine-rich repeat proteins that plants produce against polygalacturonase, a key virulence agent in pathogens. In this paper, we cloned and purified CkPGIP1, a gene product from Cynanchum komarovii that effectively inhibits polygalacturonases from Botrytis cinerea and Rhizoctonia solani. We found the expression of CkPGIP1 to be induced in response to salicylic acid, wounding, and infection with B. cinerea and R. solani. In addition, transgenic overexpression in Arabidopsis enhanced resistance against B. cinerea. Furthermore, CkPGIP1 obtained from transgenic Arabidopsis inhibited the activity of B. cinerea and R. solani polygalacturonases by 62.7-66.4% and 56.5-60.2%, respectively. Docking studies indicated that the protein interacts strongly with the B1-sheet at the N-terminus of the B. cinerea polygalacturonase, and with the C-terminus of the polygalacturonase from R. solani. This study highlights the significance of CkPGIP1 in plant disease resistance, and its possible application to manage fungal pathogens.

  16. The effects of the genetic background on herbicide resistance fitness cost and its associated dominance in Arabidopsis thaliana.

    Science.gov (United States)

    Paris, M; Roux, F; Bérard, A; Reboud, X

    2008-12-01

    The advantage of the resistance conferred by a mutation can sometimes be offset by a high fitness-cost penalty. This balance will affect possible fate of the resistance allele. Few studies have explored the impact of the genetic background on the expression of the resistance fitness cost and none has attempted to measure the variation in fitness-cost dominance. However, both the fitness penalty and its dominance may modify evolutionary trajectory and outcome. Here the impact of Arabidopsis thaliana intraspecific genetic diversity on fitness cost and its associated dominance was investigated by analysing 12 quantitative traits in crosses between a mutant conferring resistance to the herbicide 2,4-D and nine different natural genetic backgrounds. Fitness cost values were found to be more affected by intraspecific genetic diversity than fitness cost dominance, even though this effect depends on the quantitative trait measured. This observation has implications for the choice of the best strategy for preventing herbicide resistance development. In addition, our results pinpoint a potential compensatory improvement of the resistance fitness cost and its associated dominance by the genetic diversity locally present within a species.

  17. Differences in early callose deposition during adapted and non-adapted powdery mildew infection of resistant Arabidopsis lines.

    Science.gov (United States)

    Naumann, Marcel; Somerville, Shauna; Voigt, Christian

    2013-06-01

    The deposition of callose, a (1,3)-β-glucan cell wall polymer, can play an essential role in the defense response to invading pathogens. We could recently show that Arabidopsis thaliana lines with an overexpression of the callose synthase gene PMR4 gained complete penetration resistance to the adapted powdery mildew Golovinomyces cichoracearum and the non-adapted powdery mildew Blumeria graminis f. sp hordei. The penetration resistance is based on the transport of the callose synthase PMR4 to the site of attempted fungal penetration and the subsequent formation of enlarged callose deposits. The deposits differed in their total diameter comparing both types of powdery mildew infection. In this study, further characterization of these callose deposits revealed that size differences were especially pronounced in the core region of the deposits. This suggests that specific, pathogen-dependent factors exist, which might regulate callose synthase transport to the core region of forming deposits.

  18. Identification of PAD2 as a gamma-glutamylcysteine synthetase highlights the importance of glutathione in disease resistance of Arabidopsis.

    Science.gov (United States)

    Parisy, Vincent; Poinssot, Benoit; Owsianowski, Lucas; Buchala, Antony; Glazebrook, Jane; Mauch, Felix

    2007-01-01

    The Arabidopsis pad2-1 mutant belongs to a series of non-allelic camalexin-deficient mutants. It was originally described as showing enhanced susceptibility to virulent strains of Pseudomonas syringae and was later shown to be hyper-susceptible to the oomycete pathogen Phytophthora brassicae (formerly P. porri). Surprisingly, in both pathosystems, the disease susceptibility of pad2-1 was not caused by the camalexin deficiency, suggesting additional roles of PAD2 in disease resistance. The susceptibility of pad2-1 to P. brassicae was used to map the mutation to the gene At4g23100, which encodes gamma-glutamylcysteine synthetase (gamma-ECS, GSH1). GSH1 catalyzes the first committed step of glutathione (GSH) biosynthesis. The pad2-1 mutation caused an S to N transition at amino acid position 298 close to the active center. The conclusion that PAD2 encodes GSH1 is supported by several lines of evidence: (i) pad2-1 mutants contained only about 22% of wild-type amounts of GSH, (ii) genetic complementation of pad2-1 with wild-type GSH1 cDNA restored GSH production, accumulation of camalexin in response to P. syringae and resistance to P. brassicae and P. syringae, (iii) another GSH1 mutant, cad2-1, showed pad2-like phenotypes, and (iv) feeding of GSH to excised leaves of pad2-1 restored camalexin production and resistance to P. brassicae. Inoculation of Col-0 with P. brassicae caused a coordinated increase in the transcript abundance of GSH1 and GSH2, the gene encoding the second enzyme in GSH biosynthesis, and resulted in enhanced foliar GSH accumulation. The pad2-1 mutant showed enhanced susceptibility to additional pathogens, suggesting an important general role of GSH in disease resistance of Arabidopsis.

  19. Expression of antimicrobial peptides thanatin(S) in transgenic Arabidopsis enhanced resistance to phytopathogenic fungi and bacteria.

    Science.gov (United States)

    Wu, Tingquan; Tang, Dingzhong; Chen, Weida; Huang, Hexun; Wang, Rui; Chen, Yongfang

    2013-09-15

    Thanatin(S) is an analog of thanatin, an insect antimicrobial peptide possessing strong and broad spectrum of antimicrobial activity. In order to investigate if the thanatin could be used in engineering transgenic plants for increased resistance against phytopathogens, the synthetic thanatin(S) was introduced into Arabidopsis thaliana plants. To increase the expression level of thanatin(S) in plants, the coding sequence was optimized by plant-preference codon. To avoid cellular protease degradation, signal peptide of rice Cht1 was fused to N terminal of thanatin(S) for secreting the expressed thanatin(S) into intercellular spaces. To evaluate the application value of thanatin(S) in plant disease control, the synthesized coding sequence of Cht1 signal peptide (Cht1SP)-thanatin(S) was ligated to plant gateway destination binary vectors pGWB11 (with FLAG tag). Meanwhile, in order to observe the subcellular localization of Cht1SP-thanatin(S)-GFP and thanatin(S)-GFP, the sequences of Cht1SP-thanatin(S) and thanatin(S) were respectively linked to pGWB5 (with GFP tag). The constructs were transformed into Arabidopsis ecotype Col-0 and mutant pad4-1 via Agrobacterium-mediated transformation. The transformants with Cht1SP-thanatin(S)-FLAG fusion gene were analyzed by genomic PCR, real-time PCR, and western blots and the transgenic Arabidopsis plants introduced respectively Cht1SP-thanatin(S)-GFP and thanatin(S)-GFP were observed by confocal microscopy. Transgenic plants expressing Cht1SP-thanatin(S)-FLAG fusion protein showed antifungal activity against Botrytis cinerea and powdery mildew, as well as antibacterial activity against Pseudomonas syringae pv. tomato. And the results from confocal observation showed that the GFP signal from Cht1SP-thanatin(S)-GFP transgenic Arabidopsis plants occurred mainly in intercellular space, while that from thanatin(S)-GFP transgenic plants was mainly detected in the cytoplasm and that from empty vector transgenic plants was distributed

  20. Induced systemic resistance in Arabidopsis against Pseudomonas syringae pv. tomato by disease suppressive soils

    Science.gov (United States)

    Two-week-old Arabidopsis thaliana ecotype Col-0 seedlings were transferred into an autoclaved sand-soil mixture amended with 10% or 20% (weight/weight) soil that is suppressive to either take-all or Rhizoctonia root rot of wheat from fields in Washington State USA. These soils contain population siz...

  1. Arabidopsis lectin receptor kinases LecRK-IX.1 and LecRK-IX.2 are functional analogs in regulating phytophthora resistance and plant cell death

    NARCIS (Netherlands)

    Wang, Yan; Cordewener, Jan H G; America, Antoine H P; Shan, Weixing; Bouwmeester, Klaas; Govers, Francine

    2015-01-01

    L-type lectin receptor kinases (LecRK) are potential immune receptors. Here, we characterized two closely-related Arabidopsis LecRK, LecRK-IX.1 and LecRK-IX.2, of which T-DNA insertion mutants showed compromised resistance to Phytophthora brassicae and Phytophthora capsici, with double mutants showi

  2. Rhizobacteria-mediated induced systemic resistance (ISR) in Arabidopsis requires sensitivity to jasmonate and ethylene but is not accompanied by an increase in their production

    NARCIS (Netherlands)

    Pieterse, C.M.J.; Pelt, J.A. van; Ton, J.; Parchmann, S.; Mueller, M.J.; Buchala, A.J.; Métraux, J.P.; Loon, L.C. van

    2000-01-01

    Plants develop an enhanced defensive capacity against a broad spectrum of plant pathogens after colonization of the roots by selected strains of nonpathogenic biocontrol bacteria. In Arabidopsis thaliana, this induced systemic resistance (ISR) functions independently of salicylic acid but requires a

  3. β-Glucosidase BGLU42 is a MYB72-dependent key regulator of rhizobacteria-induced systemic resistance and modulates iron deficiency responses in Arabidopsis roots

    NARCIS (Netherlands)

    Zamioudis, Christos; Hanson, Johannes; Pieterse, Corné M J

    2014-01-01

    Selected soil-borne rhizobacteria can trigger an induced systemic resistance (ISR) that is effective against a broad spectrum of pathogens. In Arabidopsis thaliana, the root-specific transcription factor MYB72 is required for the onset of ISR, but is also associated with plant survival under conditi

  4. Rhizobacterial volatiles and photosynthesis-related signals coordinate MYB72 in Arabidopsis roots during onset of induced systemic resistance and iron deficiency responses

    NARCIS (Netherlands)

    Zamioudis, C.; Korteland, J.; Van Pelt, J.A.; Van Hamersveld, M.; Dombrowski, N.; Bai, Y.; Hanson, J.; Van Verk, M.C.; Ling, H.-Q.; Schulze-Lefert, P.; Pieterse, C.M.J.

    2015-01-01

    In Arabidopsis roots, the transcription factor MYB72 plays a dual role in the onset of rhizobacteria-induced systemic resistance (ISR) and plant survival under conditions of limited iron availability. Previously, it was shown that MYB72 coordinates the expression of a gene module that promotes synth

  5. Auxin Resistant1 and PIN-FORMED2 Protect Lateral Root Formation in Arabidopsis under Iron Stress.

    Science.gov (United States)

    Li, Guangjie; Song, Haiyan; Li, Baohai; Kronzucker, Herbert J; Shi, Weiming

    2015-12-01

    A stunted root system is a significant symptom of iron (Fe) toxicity, yet little is known about the effects of excess Fe on lateral root (LR) development. In this work, we show that excess Fe has different effects on LR development in different portions of the Arabidopsis (Arabidopsis thaliana) root system and that inhibitory effects on the LR initiation are only seen in roots newly formed during excess Fe exposure. We show that root tip contact with Fe is both necessary and sufficient for LR inhibition and that the auxin, but not abscisic acid, pathway is engaged centrally in the initial stages of excess Fe exposure. Furthermore, Fe stress significantly reduced PIN-FORMED2 (PIN2)-green fluorescent protein (GFP) expression in root tips, and pin2-1 mutants exhibited significantly fewer LR initiation events under excess Fe than the wild type. Exogenous application of both Fe and glutathione together increased PIN2-GFP expression and the number of LR initiation events compared with Fe treatment alone. The ethylene inhibitor aminoethoxyvinyl-glycine intensified Fe-dependent inhibition of LR formation in the wild type, and this inhibition was significantly reduced in the ethylene overproduction mutant ethylene overproducer1-1. We show that Auxin Resistant1 (AUX1) is a critical component in the mediation of endogenous ethylene effects on LR formation under excess Fe stress. Our findings demonstrate the relationship between excess Fe-dependent PIN2 expression and LR formation and the potential role of AUX1 in ethylene-mediated LR tolerance and suggest that AUX1 and PIN2 protect LR formation in Arabidopsis during the early stages of Fe stress.

  6. Arabidopsis ENHANCED DISEASE SUSCEPTIBILITY1 promotes systemic acquired resistance via azelaic acid and its precursor 9-oxo nonanoic acid.

    Science.gov (United States)

    Wittek, Finni; Hoffmann, Thomas; Kanawati, Basem; Bichlmeier, Marlies; Knappe, Claudia; Wenig, Marion; Schmitt-Kopplin, Philippe; Parker, Jane E; Schwab, Wilfried; Vlot, A Corina

    2014-11-01

    Systemic acquired resistance (SAR) is a form of inducible disease resistance that depends on salicylic acid and its upstream regulator ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1). Although local Arabidopsis thaliana defence responses activated by the Pseudomonas syringae effector protein AvrRpm1 are intact in eds1 mutant plants, SAR signal generation is abolished. Here, the SAR-specific phenotype of the eds1 mutant is utilized to identify metabolites that contribute to SAR. To this end, SAR bioassay-assisted fractionation of extracts from the wild type compared with eds1 mutant plants that conditionally express AvrRpm1 was performed. Using high-performance liquid chromatography followed by mass spectrometry, systemic immunity was associated with the accumulation of 60 metabolites, including the putative SAR signal azelaic acid (AzA) and its precursors 9-hydroperoxy octadecadienoic acid (9-HPOD) and 9-oxo nonanoic acid (ONA). Exogenous ONA induced SAR in systemic untreated leaves when applied at a 4-fold lower concentration than AzA. The data suggest that in planta oxidation of ONA to AzA might be partially responsible for this response and provide further evidence that AzA mobilizes Arabidopsis immunity in a concentration-dependent manner. The AzA fragmentation product pimelic acid did not induce SAR. The results link the C9 lipid peroxidation products ONA and AzA with systemic rather than local resistance and suggest that EDS1 directly or indirectly promotes the accumulation of ONA, AzA, or one or more of their common precursors possibly by activating one or more pathways that either result in the release of these compounds from galactolipids or promote lipid peroxidation.

  7. Multiple roles for UV RESISTANCE LOCUS8 in regulating gene expression and metabolite accumulation in Arabidopsis under solar ultraviolet radiation.

    Science.gov (United States)

    Morales, Luis O; Brosché, Mikael; Vainonen, Julia; Jenkins, Gareth I; Wargent, Jason J; Sipari, Nina; Strid, Åke; Lindfors, Anders V; Tegelberg, Riitta; Aphalo, Pedro J

    2013-02-01

    Photomorphogenic responses triggered by low fluence rates of ultraviolet B radiation (UV-B; 280-315 nm) are mediated by the UV-B photoreceptor UV RESISTANCE LOCUS8 (UVR8). Beyond our understanding of the molecular mechanisms of UV-B perception by UVR8, there is still limited information on how the UVR8 pathway functions under natural sunlight. Here, wild-type Arabidopsis (Arabidopsis thaliana) and the uvr8-2 mutant were used in an experiment outdoors where UV-A (315-400 nm) and UV-B irradiances were attenuated using plastic films. Gene expression, PYRIDOXINE BIOSYNTHESIS1 (PDX1) accumulation, and leaf metabolite signatures were analyzed. The results show that UVR8 is required for transcript accumulation of genes involved in UV protection, oxidative stress, hormone signal transduction, and defense against herbivores under solar UV. Under natural UV-A irradiance, UVR8 is likely to interact with UV-A/blue light signaling pathways to moderate UV-B-driven transcript and PDX1 accumulation. UVR8 both positively and negatively affects UV-A-regulated gene expression and metabolite accumulation but is required for the UV-B induction of phenolics. Moreover, UVR8-dependent UV-B acclimation during the early stages of plant development may enhance normal growth under long-term exposure to solar UV.

  8. Yeast cell wall extract induces disease resistance against bacterial and fungal pathogens in Arabidopsis thaliana and Brassica crop.

    Directory of Open Access Journals (Sweden)

    Mari Narusaka

    Full Text Available Housaku Monogatari (HM is a plant activator prepared from a yeast cell wall extract. We examined the efficacy of HM application and observed that HM treatment increased the resistance of Arabidopsis thaliana and Brassica rapa leaves to bacterial and fungal infections. HM reduced the severity of bacterial leaf spot and anthracnose on A. thaliana and Brassica crop leaves with protective effects. In addition, gene expression analysis of A. thaliana plants after treatment with HM indicated increased expression of several plant defense-related genes. HM treatment appears to induce early activation of jasmonate/ethylene and late activation of salicylic acid (SA pathways. Analysis using signaling mutants revealed that HM required SA accumulation and SA signaling to facilitate resistance to the bacterial pathogen Pseudomonas syringae pv. maculicola and the fungal pathogen Colletotrichum higginsianum. In addition, HM-induced resistance conferred chitin-independent disease resistance to bacterial pathogens in A. thaliana. These results suggest that HM contains multiple microbe-associated molecular patterns that activate defense responses in plants. These findings suggest that the application of HM is a useful tool that may facilitate new disease control methods.

  9. Expression of BvGLP-1 encoding a germin-like protein from sugar beet in Arabidopsis thaliana leads to resistance against phytopathogenic fungi.

    Science.gov (United States)

    Knecht, Katrin; Seyffarth, Monique; Desel, Christine; Thurau, Tim; Sherameti, Irena; Lou, Binggan; Oelmüller, Ralf; Cai, Daguang

    2010-04-01

    Nematode (Heterodera schachtii) resistance in sugar beet (Beta vulgaris) is controlled by a single dominant resistance gene, Hs1(pro-1). BvGLP-1 was cloned from resistant sugar beet. The BvGLP-1 messenger (m)RNA is highly upregulated in the resistant plants after nematode infection, suggesting its role in the Hs1(pro-1) mediated resistance. BvGLP-1 exhibits sequence homology to a set of plant germin-like proteins (GLP), from which several have proved to be functional in plant basal or defense resistance against fungal pathogens. To test whether BvGLP-1 is also involved in the plant-fungus interaction, we transferred BvGLP-1 into Arabidopsis and challenged the transgenic plants with the pathogenic fungi Verticillium longisporum and Rhizoctonia solani as well as with the beneficial endophytic fungus Piriformospora indica. The expression of BvGLP-1 in Arabidopsis elevated the H(2)O(2) content and conferred significant resistance to V. longisporum and R. solani but did not affect the beneficial interaction with P. indica in seedlings. Microscopic observations revealed a dramatic reduction in the amount of hyphae of the pathogenic fungi on the root surface as well as of fungal mycelium developed inside the roots of transgenic Arabidopsis compared with wild-type plants. Molecular analysis demonstrated that the BvGLP-1 expression in Arabidopsis constitutively activates the expression of a subset of plant defense-related proteins such as PR-1 to PR-4 and PDF1.2 but not PDF2.1 and PDF2.3. In contrast, the PDF2.1 mRNA level was downregulated. These data suggest an important role of BvGLP-1 in establishment of plant defense responses, which follow specific signaling routes that diverge from those induced by the beneficial fungus.

  10. Transcriptomics and knockout mutant analysis of rhizobacteria-mediated induced systemic resistance in Arabidopsis

    NARCIS (Netherlands)

    Verhagen, B.W.M.

    2004-01-01

    A classic example of induced resistance is triggered after infection by a necrotizing pathogen, rendering uninfected,distal parts more resistant to subsequent pathogen attack, and is often referred to as systemic acquired resistance (SAR). A phenotypically comparable type of induced resistance is tr

  11. Engineering of CRISPR/Cas9‐mediated potyvirus resistance in transgene‐free Arabidopsis plants

    Science.gov (United States)

    Pyott, Douglas E.; Sheehan, Emma

    2016-01-01

    Summary Members of the eukaryotic translation initiation factor (eIF) gene family, including eIF4E and its paralogue eIF(iso)4E, have previously been identified as recessive resistance alleles against various potyviruses in a range of different hosts. However, the identification and introgression of these alleles into important crop species is often limited. In this study, we utilise CRISPR/Cas9 technology to introduce sequence‐specific deleterious point mutations at the eIF(iso)4E locus in Arabidopsis thaliana to successfully engineer complete resistance to Turnip mosaic virus (TuMV), a major pathogen in field‐grown vegetable crops. By segregating the induced mutation from the CRISPR/Cas9 transgene, we outline a framework for the production of heritable, homozygous mutations in the transgene‐free T2 generation in self‐pollinating species. Analysis of dry weights and flowering times for four independent T3 lines revealed no differences from wild‐type plants under standard growth conditions, suggesting that homozygous mutations in eIF(iso)4E do not affect plant vigour. Thus, the established CRISPR/Cas9 technology provides a new approach for the generation of Potyvirus resistance alleles in important crops without the use of persistent transgenes. PMID:27103354

  12. Constitutive cyclic GMP accumulation in Arabidopsis thaliana compromises systemic acquired resistance induced by an avirulent pathogen by modulating local signals.

    Science.gov (United States)

    Hussain, Jamshaid; Chen, Jian; Locato, Vittoria; Sabetta, Wilma; Behera, Smrutisanjita; Cimini, Sara; Griggio, Francesca; Martínez-Jaime, Silvia; Graf, Alexander; Bouneb, Mabrouk; Pachaiappan, Raman; Fincato, Paola; Blanco, Emanuela; Costa, Alex; De Gara, Laura; Bellin, Diana; de Pinto, Maria Concetta; Vandelle, Elodie

    2016-11-04

    The infection of Arabidopsis thaliana plants with avirulent pathogens causes the accumulation of cGMP with a biphasic profile downstream of nitric oxide signalling. However, plant enzymes that modulate cGMP levels have yet to be identified, so we generated transgenic A. thaliana plants expressing the rat soluble guanylate cyclase (GC) to increase genetically the level of cGMP and to study the function of cGMP in plant defence responses. Once confirmed that cGMP levels were higher in the GC transgenic lines than in wild-type controls, the GC transgenic plants were then challenged with bacterial pathogens and their defence responses were characterized. Although local resistance was similar in the GC transgenic and wild-type lines, differences in the redox state suggested potential cross-talk between cGMP and the glutathione redox system. Furthermore, large-scale transcriptomic and proteomic analysis highlighted the significant modulation of both gene expression and protein abundance at the infection site, inhibiting the establishment of systemic acquired resistance. Our data indicate that cGMP plays a key role in local responses controlling the induction of systemic acquired resistance in plants challenged with avirulent pathogens.

  13. Ectopically expressed sweet pepper ferredoxin PFLP enhances disease resistance to Pectobacterium carotovorum subsp. carotovorum affected by harpin and protease-mediated hypersensitive response in Arabidopsis.

    Science.gov (United States)

    Ger, Mang-Jye; Louh, Guan-Yu; Lin, Yi-Hsien; Feng, Teng-Yung; Huang, Hsiang-En

    2014-12-01

    Plant ferredoxin-like protein (PFLP) is a photosynthesis-type ferredoxin (Fd) found in sweet pepper. It contains an iron-sulphur cluster that receives and delivers electrons between enzymes involved in many fundamental metabolic processes. It has been demonstrated that transgenic plants overexpressing PFLP show a high resistance to many bacterial pathogens, although the mechanism remains unclear. In this investigation, the PFLP gene was transferred into Arabidopsis and its defective derivatives, such as npr1 (nonexpresser of pathogenesis-related gene 1) and eds1 (enhanced disease susceptibility 1) mutants and NAHG-transgenic plants. These transgenic plants were then infected with the soft-rot bacterial pathogen Pectobacterium carotovorum subsp. carotovorum (Erwinia carotovora ssp. carotovora, ECC) to investigate the mechanism behind PFLP-mediated resistance. The results revealed that, instead of showing soft-rot symptoms, ECC activated hypersensitive response (HR)-associated events, such as the accumulation of hydrogen peroxide (H2 O2 ), electrical conductivity leakage and expression of the HR marker genes (ATHSR2 and ATHSR3) in PFLP-transgenic Arabidopsis. This PFLP-mediated resistance could be abolished by inhibitors, such as diphenylene iodonium (DPI), 1-l-trans-epoxysuccinyl-leucylamido-(4-guanidino)-butane (E64) and benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-VAD-fmk), but not by myriocin and fumonisin. The PFLP-transgenic plants were resistant to ECC, but not to its harpin mutant strain ECCAC5082. In the npr1 mutant and NAHG-transgenic Arabidopsis, but not in the eds1 mutant, overexpression of the PFLP gene increased resistance to ECC. Based on these results, we suggest that transgenic Arabidopsis contains high levels of ectopic PFLP; this may lead to the recognition of the harpin and to the activation of the HR and other resistance mechanisms, and is dependent on the protease-mediated pathway.

  14. Arabidopsis Elongator subunit 2 positively contributes to resistance to the necrotrophic fungal pathogens Botrytis cinerea and Alternaria brassicicola.

    Science.gov (United States)

    Wang, Chenggang; Ding, Yezhang; Yao, Jin; Zhang, Yanping; Sun, Yijun; Colee, James; Mou, Zhonglin

    2015-09-01

    The evolutionarily conserved Elongator complex functions in diverse biological processes including salicylic acid-mediated immune response. However, how Elongator functions in jasmonic acid (JA)/ethylene (ET)-mediated defense is unknown. Here, we show that Elongator is required for full induction of the JA/ET defense pathway marker gene PLANT DEFENSIN1.2 (PDF1.2) and for resistance to the necrotrophic fungal pathogens Botrytis cinerea and Alternaria brassicicola. A loss-of-function mutation in the Arabidopsis Elongator subunit 2 (ELP2) alters B. cinerea-induced transcriptome reprogramming. Interestingly, in elp2, expression of WRKY33, OCTADECANOID-RESPONSIVE ARABIDOPSIS AP2/ERF59 (ORA59), and PDF1.2 is inhibited, whereas transcription of MYC2 and its target genes is enhanced. However, overexpression of WRKY33 or ORA59 and mutation of MYC2 fail to restore PDF1.2 expression and B. cinerea resistance in elp2, suggesting that ELP2 is required for induction of not only WRKY33 and ORA59 but also PDF1.2. Moreover, elp2 is as susceptible as coronatine-insensitive1 (coi1) and ethylene-insensitive2 (ein2) to B. cinerea, indicating that ELP2 is an important player in B. cinerea resistance. Further analysis of the lesion sizes on the double mutants elp2 coi1 and elp2 ein2 and the corresponding single mutants revealed that the function of ELP2 overlaps with COI1 and is additive to EIN2 for B. cinerea resistance. Finally, basal histone acetylation levels in the coding regions of WRKY33, ORA59, and PDF1.2 are reduced in elp2 and a functional ELP2-GFP fusion protein binds to the chromatin of these genes, suggesting that constitutive ELP2-mediated histone acetylation may be required for full activation of the WRKY33/ORA59/PDF1.2 transcriptional cascade.

  15. Strong Suppression of Systemic Acquired Resistance in Arabidopsis by NRR is Dependent on its Ability to Interact with NPR1and its Putative Repression Domain

    Institute of Scientific and Technical Information of China (English)

    Mawsheng Chern; Patrick E. Canlas; Pamela C. Ronald

    2008-01-01

    Systemic Acquired Resistance (SAR) in plants confers lasting broad-spectrum resistance to pathogens and requires the phytohormone salicylic acid (SA). Arabidopsis NPR1/NIM1 is a key regulator of the SAR response. Studies attempting to reveal the function of NPR1 and how it mediates SA signaling have led to isolation of two classes of proteins that interact with NPRI: the first class includes rice NRR, Arabidopsis NIMIN1, NIMIN2, and NIMIN3, and tobacco NIMIN2-1ike proteins; the second class belongs to TGA transcription factors. We have previously shown that overexpression of NRR in rice suppresses both basal and Xa21-mediated resistance. In order to test whether NRR affects SA-induced, NPRl-mediated SAR, we have transformed Arabidopsis with the rice NRR gene and tested its effects on the defense response. Expression of NRR in Arabidopsis results in suppression of PR gene induction by SAR inducer and resistance to pathogens. These phenotypes are even more severe than those of the nprl- 1 mutant. The ability of NRR to suppress PR gene induction and disease resistance is correlated with its ability to bind to NPR1 because two point mutations in NRR, which reduce NPR1 binding, fail to suppress NPR1. In contrast, wild-type and a mutant NRR, which still binds to NPR1 strongly, retain the ability to suppress the SAR response. Replacing the C-terminal 79 amino acids of NRR with the VP16 activation domain turns the fusion protein into a transcriptional co-activator. These results indicate that NRR binds to NPR1 in vivo in a protein complex to inhibit transcriptional activation of PR genes and that NRR contains a transcription repression domain for active repression.

  16. Characterization of an Arabidopsis-Phytophthora pathosystem: resistance requires a functional PAD2 gene and is independent of salicylic acid, ethylene and jasmonic acid signalling.

    Science.gov (United States)

    Roetschi, A; Si-Ammour, A; Belbahri, L; Mauch, F; Mauch-Mani, B

    2001-11-01

    Arabidopsis accessions were screened with isolates of Phytophthora porri originally isolated from other crucifer species. The described Arabidopsis-Phytophthora pathosystem shows the characteristics of a facultative biotrophic interaction similar to that seen in agronomically important diseases caused by Phytophthora species. In susceptible accessions, extensive colonization of the host tissue occurred and sexual and asexual spores were formed. In incompatible combinations, the plants reacted with a hypersensitive response (HR) and the formation of papillae at the sites of attempted penetration. Defence pathway mutants such as jar1 (jasmonic acid-insensitive), etr1 (ethylene receptor mutant) and ein2 (ethylene-insensitive) remained resistant towards P. porri. However, pad2, a mutant with reduced production of the phytoalexin camalexin, was hyper-susceptible. The accumulation of salicylic acid (SA) and PR1 protein was strongly reduced in pad2. Surprisingly, this lack of SA accumulation does not appear to be the cause of the hyper-susceptibility because interference with SA signalling in nahG plants or sid2 or npr1 mutants had only a minor effect on resistance. In addition, the functional SA analogue benzothiadiazol (BTH) did not induce resistance in susceptible plants including pad2. Similarly, the complete blockage of camalexin biosynthesis in pad3 did not cause susceptibility. Resistance of Arabidopsis against P. porri appears to depend on unknown defence mechanisms that are under the control of PAD2.

  17. Ethylmethanesulfonate Saturation Mutagenesis in Arabidopsis to Determine Frequency of Herbicide Resistance

    Science.gov (United States)

    Plant resistance to glyphosate has been reported far less frequently than resistance to sulfonylurea and imidazolinone herbicides. However, these studies tend to be anecdotal, without side by side comparisons for a single species or natural isolate. In this study, we tested the frequencies of resist...

  18. Systemic resistance induced by volatile organic compounds emitted by plant growth-promoting fungi in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Hushna Ara Naznin

    Full Text Available Volatile organic compounds (VOC were extracted and identified from plant growth-promoting fungi (PGPF, Phoma sp., Cladosporium sp. and Ampelomyces sp., using gas chromatography-mass spectrometry (GC-MS. Among the three VOC extracted, two VOC blends (emitted from Ampelomyces sp. and Cladosporium sp. significantly reduced disease severity in Arabidopsis plants against Pseudomonas syringae pv. tomato DC3000 (Pst. Subsequently, m-cresol and methyl benzoate (MeBA were identified as major active volatile compounds from Ampelomyces sp. and Cladosporium sp., respectively, and found to elicit induced systemic resistance (ISR against the pathogen. Molecular signaling for disease suppression by the VOC were investigated by treating different mutants and transgenic Arabidopsis plants impaired in salicylic acid (SA or Jasmonic acid (JA/ethylene (ET signaling pathways with m-cresol and MeBA followed by challenge inoculation with Pst. Results show that the level of protection was significantly lower when JA/ET-impaired mutants were treated with MeBA, and in SA-, and JA/ET-disrupted mutants after m-cresol treatment, indicating the involvement of these signal transduction pathways in the ISR primed by the volatiles. Analysis of defense-related genes by real-time qRT-PCR showed that both the SA-and JA-signaling pathways combine in the m-cresol signaling of ISR, whereas MeBA is mainly involved in the JA-signaling pathway with partial recruitment of SA-signals. The ET-signaling pathway was not employed in ISR by the volatiles. Therefore, this study identified two novel volatile components capable of eliciting ISR that may be promising candidates in biological control strategy to protect plants from diseases.

  19. Systemic resistance induced by volatile organic compounds emitted by plant growth-promoting fungi in Arabidopsis thaliana.

    Science.gov (United States)

    Naznin, Hushna Ara; Kiyohara, Daigo; Kimura, Minako; Miyazawa, Mitsuo; Shimizu, Masafumi; Hyakumachi, Mitsuro

    2014-01-01

    Volatile organic compounds (VOC) were extracted and identified from plant growth-promoting fungi (PGPF), Phoma sp., Cladosporium sp. and Ampelomyces sp., using gas chromatography-mass spectrometry (GC-MS). Among the three VOC extracted, two VOC blends (emitted from Ampelomyces sp. and Cladosporium sp.) significantly reduced disease severity in Arabidopsis plants against Pseudomonas syringae pv. tomato DC3000 (Pst). Subsequently, m-cresol and methyl benzoate (MeBA) were identified as major active volatile compounds from Ampelomyces sp. and Cladosporium sp., respectively, and found to elicit induced systemic resistance (ISR) against the pathogen. Molecular signaling for disease suppression by the VOC were investigated by treating different mutants and transgenic Arabidopsis plants impaired in salicylic acid (SA) or Jasmonic acid (JA)/ethylene (ET) signaling pathways with m-cresol and MeBA followed by challenge inoculation with Pst. Results show that the level of protection was significantly lower when JA/ET-impaired mutants were treated with MeBA, and in SA-, and JA/ET-disrupted mutants after m-cresol treatment, indicating the involvement of these signal transduction pathways in the ISR primed by the volatiles. Analysis of defense-related genes by real-time qRT-PCR showed that both the SA-and JA-signaling pathways combine in the m-cresol signaling of ISR, whereas MeBA is mainly involved in the JA-signaling pathway with partial recruitment of SA-signals. The ET-signaling pathway was not employed in ISR by the volatiles. Therefore, this study identified two novel volatile components capable of eliciting ISR that may be promising candidates in biological control strategy to protect plants from diseases.

  20. Induced systemic resistance in Arabidopsis thaliana against Pseudomonas syringae pv. tomato by 2,4-diacetylphloroglucinol-producing Pseudomonas fluorescens.

    Science.gov (United States)

    Weller, David M; Mavrodi, Dmitri V; van Pelt, Johan A; Pieterse, Corné M J; van Loon, Leendert C; Bakker, Peter A H M

    2012-04-01

    Pseudomonas fluorescens strains that produce the polyketide antibiotic 2,4-diacetylphloroglucinol (2,4-DAPG) are among the most effective rhizobacteria that suppress root and crown rots, wilts, and damping-off diseases of a variety of crops, and they play a key role in the natural suppressiveness of some soils to certain soilborne pathogens. Root colonization by 2,4-DAPG-producing P. fluorescens strains Pf-5 (genotype A), Q2-87 (genotype B), Q8r1-96 (genotype D), and HT5-1 (genotype N) produced induced systemic resistance (ISR) in Arabidopsis thaliana accession Col-0 against bacterial speck caused by P. syringae pv. tomato. The ISR-eliciting activity of the four bacterial genotypes was similar, and all genotypes were equivalent in activity to the well-characterized strain P. fluorescens WCS417r. The 2,4-DAPG biosynthetic locus consists of the genes phlHGF and phlACBDE. phlD or phlBC mutants of Q2-87 (2,4-DAPG minus) were significantly reduced in ISR activity, and genetic complementation of the mutants restored ISR activity back to wild-type levels. A phlF regulatory mutant (overproducer of 2,4-DAPG) had ISR activity equivalent to the wild-type Q2-87. Introduction of DAPG into soil at concentrations of 10 to 250 μM 4 days before challenge inoculation induced resistance equivalent to or better than the bacteria. Strain Q2-87 induced resistance on transgenic NahG plants but not on npr1-1, jar1, and etr1 Arabidopsis mutants. These results indicate that the antibiotic 2,4-DAPG is a major determinant of ISR in 2,4-DAPG-producing P. fluorescens, that the genotype of the strain does not affect its ISR activity, and that the activity induced by these bacteria operates through the ethylene- and jasmonic acid-dependent signal transduction pathway.

  1. Decreased abundance of type III secretion system-inducing signals in Arabidopsis mkp1 enhances resistance against Pseudomonas syringae

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Jeffrey C.; Wan, Ying; Kim, Young-Mo; Pasa-Tolic, Ljiljana; Metz, Thomas O.; Peck, Scott C.

    2014-04-21

    Many phytopathogenic bacteria use a type III secretion system (T3SS) to inject defense-suppressing effector proteins into host cells. Genes encoding the T3SS are induced at the start of infection, yet host signals that initiate T3SS gene expression are poorly understood. Here we identify several plant-derived metabolites that induce the T3SS in the bacterial pathogen Pseudomonas syringae pv tomato DC3000. In addition, we report that mkp1 (mapk phosphatase 1), an Arabidopsis mutant that is more resistant to bacterial infection, produces decreased levels of these T3SS-inducing metabolites. Consistent with the observed decrease in these metabolites, T3SS effector delivery by DC3000 was impaired in mkp1. Addition of the bioactive metabolites to the mkp1-DC3000 interaction fully restored T3SS effector delivery and suppressed enhanced resistance in mkp1. Together, these results demonstrate that DC3000 perceives multiple signals derived from plants to initiate their virulence program, and reveal a new layer of molecular communication between plants and these pathogenic bacteria.

  2. Arabidopsis flowering locus D influences systemic-acquired-resistance- induced expression and histone modifications of WRKY genes.

    Science.gov (United States)

    Singh, Vijayata; Roy, Shweta; Singh, Deepjyoti; Nandi, Ashis Kumar

    2014-03-01

    A plant that is in part infected by a pathogen is more resistant throughout its whole body to subsequent infections--a phenomenon known as systemic acquired resistance (SAR). Mobile signals are synthesized at the site of infection and distributed throughout the plant through vascular tissues. Mechanism of SAR development subsequent to reaching the mobile signal in the distal tissue is largely unknown. Recently we showed that flowering locus D (FLD) gene of Arabidopsis thaliana is required in the distal tissue to activate SAR. FLD codes for a homologue of human-lysine-specific histone demethylase. Here we show that FLD function is required for priming (SAR induced elevated expression during challenge inoculation) of WRKY29 and WRKY6 genes. FLD also differentially influences basal and SAR-induced expression of WRKY38, WRKY65 and WRKY53 genes. In addition, we also show that FLD partly localizes in nucleus and influences histone modifications at the promoters of WRKY29 and WRKY6 genes. The results altogether indicate to the possibility of FLD's involvement in epigenetic regulation of SAR.

  3. ZmNAC55, a maize stress-responsive NAC transcription factor, confers drought resistance in transgenic Arabidopsis.

    Science.gov (United States)

    Mao, Hude; Yu, Lijuan; Han, Ran; Li, Zhanjie; Liu, Hui

    2016-08-01

    Abiotic stress has been shown to significantly limit the growth and productivity of crops. NAC transcription factors play essential roles in response to various abiotic stresses. However, only little information regarding stress-related NAC genes is available in maize. Here, we cloned a maize NAC transcription factor ZmNAC55 and identified its function in drought stress. Transient expression and transactivation assay demonstrated that ZmNAC55 was localized in the nucleus and had transactivation activity. Expression analysis of ZmNAC55 in maize showed that this gene was induced by drought, high salinity and cold stresses and by abscisic acid (ABA). Promoter analysis demonstrated that multiple stress-related cis-acting elements exist in promoter region of ZmNAC55. Overexpression of ZmNAC55 in Arabidopsis led to hypersensitivity to ABA at the germination stage, but enhanced drought resistence compared to wild-type seedlings. Transcriptome analysis identified a number of differentially expressed genes between 35S::ZmNAC55 transgenic and wild-type plants, and many of which are involved in stress response, including twelve qRT-PCR confirmed well-known drought-responsive genes. These results highlight the important role of ZmNAC55 in positive regulates of drought resistence, and may have potential applications in transgenic breeding of drought-tolerant crops.

  4. Different requirements for EDS1 and NDR1 by disease resistance genes define at least two R gene-mediated signaling pathways in Arabidopsis.

    Science.gov (United States)

    Aarts, N; Metz, M; Holub, E; Staskawicz, B J; Daniels, M J; Parker, J E

    1998-08-18

    The Arabidopsis genes EDS1 and NDR1 were shown previously by mutational analysis to encode essential components of race-specific disease resistance. Here, we examined the relative requirements for EDS1 and NDR1 by a broad spectrum of Resistance (R) genes present in three Arabidopsis accessions (Columbia, Landsberg-erecta, and Wassilewskija). We show that there is a strong requirement for EDS1 by a subset of R loci (RPP2, RPP4, RPP5, RPP21, and RPS4), conferring resistance to the biotrophic oomycete Peronospora parasitica, and to Pseudomonas bacteria expressing the avirulence gene avrRps4. The requirement for NDR1 by these EDS1-dependent R loci is either weak or not measurable. Conversely, three NDR1-dependent R loci, RPS2, RPM1, and RPS5, operate independently of EDS1. Another RPP locus, RPP8, exhibits no strong exclusive requirement for EDS1 or NDR1 in isolate-specific resistance to P. parasitica, although resistance is compromised weakly by eds1. Similarly, resistance conditioned by two EDS1-dependent RPP genes, RPP4 and RPP5, is impaired partially by ndr1, implicating a degree of pathway cross-talk. Our results provide compelling evidence for the preferential utilization of either signaling component by particular R genes and thus define at least two disease resistance pathways. The data also suggest that strong dependence on EDS1 or NDR1 is governed by R protein structural type rather than pathogen class.

  5. Accumulation of isochorismate-derived 2,3-dihydroxybenzoic 3-O-beta-D-xyloside in arabidopsis resistance to pathogens and ageing of leaves.

    Science.gov (United States)

    Bartsch, Michael; Bednarek, Paweł; Vivancos, Pedro D; Schneider, Bernd; von Roepenack-Lahaye, Edda; Foyer, Christine H; Kombrink, Erich; Scheel, Dierk; Parker, Jane E

    2010-08-13

    An intricate network of hormone signals regulates plant development and responses to biotic and abiotic stress. Salicylic acid (SA), derived from the shikimate/isochorismate pathway, is a key hormone in resistance to biotrophic pathogens. Several SA derivatives and associated modifying enzymes have been identified and implicated in the storage and channeling of benzoic acid intermediates or as bioactive molecules. However, the range and modes of action of SA-related metabolites remain elusive. In Arabidopsis, Enhanced Disease Susceptibility 1 (EDS1) promotes SA-dependent and SA-independent responses in resistance against pathogens. Here, we used metabolite profiling of Arabidopsis wild type and eds1 mutant leaf extracts to identify molecules, other than SA, whose accumulation requires EDS1 signaling. Nuclear magnetic resonance and mass spectrometry of isolated and purified compounds revealed 2,3-dihydroxybenzoic acid (2,3-DHBA) as an isochorismate-derived secondary metabolite whose accumulation depends on EDS1 in resistance responses and during ageing of plants. 2,3-DHBA exists predominantly as a xylose-conjugated form (2-hydroxy-3-beta-O-D-xylopyranosyloxy benzoic acid) that is structurally distinct from known SA-glucose conjugates. Analysis of DHBA accumulation profiles in various Arabidopsis mutants suggests an enzymatic route to 2,3-DHBA synthesis that is under the control of EDS1. We propose that components of the EDS1 pathway direct the generation or stabilization of 2,3-DHBA, which as a potentially bioactive molecule is sequestered as a xylose conjugate.

  6. Increased resistance to biotrophic pathogens in the Arabidopsis constitutive induced resistance 1 mutant is EDS1 and PAD4-dependent and modulated by environmental temperature.

    Science.gov (United States)

    Carstens, Maryke; McCrindle, Tyronne K; Adams, Nicolette; Diener, Anastashia; Guzha, Delroy T; Murray, Shane L; Parker, Jane E; Denby, Katherine J; Ingle, Robert A

    2014-01-01

    The Arabidopsis constitutive induced resistance 1 (cir1) mutant displays salicylic acid (SA)-dependent constitutive expression of defence genes and enhanced resistance to biotrophic pathogens. To further characterise the role of CIR1 in plant immunity we conducted epistasis analyses with two key components of the SA-signalling branch of the defence network, ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1) and PHYTOALEXIN DEFICIENT4 (PAD4). We demonstrate that the constitutive defence phenotypes of cir1 require both EDS1 and PAD4, indicating that CIR1 lies upstream of the EDS1-PAD4 regulatory node in the immune signalling network. In light of this finding we examined EDS1 expression in cir1 and observed increased protein, but not mRNA levels in this mutant, suggesting that CIR1 might act as a negative regulator of EDS1 via a post-transcriptional mechanism. Finally, as environmental temperature is known to influence the outcome of plant-pathogen interactions, we analysed cir1 plants grown at 18, 22 or 25°C. We found that susceptibility to Pseudomonas syringae pv. tomato (Pst) DC3000 is modulated by temperature in cir1. Greatest resistance to this pathogen (relative to PR-1:LUC control plants) was observed at 18°C, while at 25°C no difference in susceptibility between cir1 and control plants was apparent. The increase in resistance to Pst DC3000 at 18°C correlated with a stunted growth phenotype, suggesting that activation of defence responses may be enhanced at lower temperatures in the cir1 mutant.

  7. Increased resistance to biotrophic pathogens in the Arabidopsis constitutive induced resistance 1 mutant is EDS1 and PAD4-dependent and modulated by environmental temperature.

    Directory of Open Access Journals (Sweden)

    Maryke Carstens

    Full Text Available The Arabidopsis constitutive induced resistance 1 (cir1 mutant displays salicylic acid (SA-dependent constitutive expression of defence genes and enhanced resistance to biotrophic pathogens. To further characterise the role of CIR1 in plant immunity we conducted epistasis analyses with two key components of the SA-signalling branch of the defence network, ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1 and PHYTOALEXIN DEFICIENT4 (PAD4. We demonstrate that the constitutive defence phenotypes of cir1 require both EDS1 and PAD4, indicating that CIR1 lies upstream of the EDS1-PAD4 regulatory node in the immune signalling network. In light of this finding we examined EDS1 expression in cir1 and observed increased protein, but not mRNA levels in this mutant, suggesting that CIR1 might act as a negative regulator of EDS1 via a post-transcriptional mechanism. Finally, as environmental temperature is known to influence the outcome of plant-pathogen interactions, we analysed cir1 plants grown at 18, 22 or 25°C. We found that susceptibility to Pseudomonas syringae pv. tomato (Pst DC3000 is modulated by temperature in cir1. Greatest resistance to this pathogen (relative to PR-1:LUC control plants was observed at 18°C, while at 25°C no difference in susceptibility between cir1 and control plants was apparent. The increase in resistance to Pst DC3000 at 18°C correlated with a stunted growth phenotype, suggesting that activation of defence responses may be enhanced at lower temperatures in the cir1 mutant.

  8. Quantification of induced resistance against Phytophthora species expressing GFP as a vital marker: beta-aminobutyric acid but not BTH protects potato and Arabidopsis from infection.

    Science.gov (United States)

    Si-Ammour, Azeddine; Mauch-Mani, Brigitte; Mauch, Felix

    2003-07-01

    SUMMARY Induced resistance was studied in the model pathosystem Arabidopsis-Phytophthora brassicae (formerly P. porri) in comparison with the agronomically important late blight disease of potato caused by Phytophthora infestans. For the quantification of disease progress, both Phytophthora species were transformed with the vector p34GFN carrying the selectable marker gene neomycine phosphotransferase (nptII) and the reporter gene green fluorescent protein (gfp). Eighty five per cent of the transformants of P. brassicae and P. infestans constitutively expressed GFP at high levels at all developmental stages both in vitro and in planta. Transformants with high GFP expression and normal in vitro growth and virulence were selected to quantify pathogen growth by measuring the in planta emitted GFP fluorescence. This non-destructive monitoring of the infection process was applied to analyse the efficacy of two chemical inducers of disease resistance, a functional SA-analogue, benzothiadiazole (BTH), and beta-aminobutyric acid (BABA) which is involved in priming mechanisms of unknown nature. BABA pre-treatment (300 microm) via soil drench applied 24 h before inoculation completely protected the susceptible Arabidopsis accession Landsberg erecta (Ler) from infection with P. brassicae. A similar treatment with BTH (330 microm) did not induce resistance. Spraying the susceptible potato cultivar Bintje with BABA (1 mm) 2 days before inoculation resulted in a phenocopy of the incompatible interaction shown by the resistant potato cultivar Matilda while BTH (1.5 mm) did not protect Bintje from severe infection. Thus, in both pathosystems, the mechanisms of induced resistance appeared to be similar, suggesting that the Arabidopsis-P. brassicae pathosystem is a promising model for the molecular analysis of induced resistance mechanisms of potato against the late blight disease.

  9. Arabidopsis Lectin Receptor Kinases LecRK-IX.1 and LecRK-IX.2 Are Functional Analogs in Regulating Phytophthora Resistance and Plant Cell Death.

    Science.gov (United States)

    Wang, Yan; Cordewener, Jan H G; America, Antoine H P; Shan, Weixing; Bouwmeester, Klaas; Govers, Francine

    2015-09-01

    L-type lectin receptor kinases (LecRK) are potential immune receptors. Here, we characterized two closely-related Arabidopsis LecRK, LecRK-IX.1 and LecRK-IX.2, of which T-DNA insertion mutants showed compromised resistance to Phytophthora brassicae and Phytophthora capsici, with double mutants showing additive susceptibility. Overexpression of LecRK-IX.1 or LecRK-IX.2 in Arabidopsis and transient expression in Nicotiana benthamiana increased Phytophthora resistance but also induced cell death. Phytophthora resistance required both the lectin domain and kinase activity, but for cell death, the lectin domain was not needed. Silencing of the two closely related mitogen-activated protein kinase genes NbSIPK and NbNTF4 in N. benthamiana completely abolished LecRK-IX.1-induced cell death but not Phytophthora resistance. Liquid chromatography-mass spectrometry analysis of protein complexes coimmunoprecipitated in planta with LecRK-IX.1 or LecRK-IX.2 as bait, resulted in the identification of the N. benthamiana ABC transporter NbPDR1 as a potential interactor of both LecRK. The closest homolog of NbPDR1 in Arabidopsis is ABCG40, and coimmunoprecipitation experiments showed that ABCG40 associates with LecRK-IX.1 and LecRK-IX.2 in planta. Similar to the LecRK mutants, ABCG40 mutants showed compromised Phytophthora resistance. This study shows that LecRK-IX.1 and LecRK-IX.2 are Phytophthora resistance components that function independent of each other and independent of the cell-death phenotype. They both interact with the same ABC transporter, suggesting that they exploit similar signal transduction pathways.

  10. Both the Jasmonic Acid and the Salicylic Acid Pathways Contribute to Resistance to the Biotrophic Clubroot Agent Plasmodiophora brassicae in Arabidopsis.

    Science.gov (United States)

    Lemarié, Séverine; Robert-Seilaniantz, Alexandre; Lariagon, Christine; Lemoine, Jocelyne; Marnet, Nathalie; Jubault, Mélanie; Manzanares-Dauleux, Maria J; Gravot, Antoine

    2015-11-01

    The role of salicylic acid (SA) and jasmonic acid (JA) signaling in resistance to root pathogens has been poorly documented. We assessed the contribution of SA and JA to basal and partial resistance of Arabidopsis to the biotrophic clubroot agent Plasmodiophora brassicae. SA and JA levels as well as the expression of the SA-responsive genes PR2 and PR5 and the JA-responsive genes ARGAH2 and THI2.1 were monitored in infected roots of the accessions Col-0 (susceptible) and Bur-0 (partially resistant). SA signaling was activated in Bur-0 but not in Col-0. The JA pathway was weakly activated in Bur-0 but was strongly induced in Col-0. The contribution of both pathways to clubroot resistance was then assessed using exogenous phytohormone application and mutants affected in SA or JA signaling. Exogenous SA treatment decreased clubroot symptoms in the two Arabidopsis accessions, whereas JA treatment reduced clubroot symptoms only in Col-0. The cpr5-2 mutant, in which SA responses are constitutively induced, was more resistant to clubroot than the corresponding wild type, and the JA signaling-deficient mutant jar1 was more susceptible. Finally, we showed that the JA-mediated induction of NATA1 drove N(δ)-acetylornithine biosynthesis in infected Col-0 roots. The 35S::NATA1 and nata1 lines displayed reduced or enhanced clubroot symptoms, respectively, thus suggesting that in Col-0 this pathway was involved in the JA-mediated basal clubroot resistance. Overall, our data support the idea that, depending on the Arabidopsis accession, both SA and JA signaling can play a role in partial inhibition of clubroot development in compatible interactions with P. brassicae.

  11. Expression of the grape VqSTS21 gene in Arabidopsis confers resistance to osmotic stress and biotrophic pathogens but not Botrytis cinerea

    Directory of Open Access Journals (Sweden)

    Li Huang

    2016-09-01

    Full Text Available Stilbene synthase (STS is a key gene in the biosynthesis of various stilbenoids, including resveratrol and its derivative glucosides (such as piceid, that has been shown to contribute to disease resistance in plants. However, the mechanism behind such a role has yet to be elucidated. Furthermore, the function of STS genes in osmotic stress tolerance remains unclear. As such, we sought to elucidate the role of STS genes in the defense against biotic and abiotic stress in the model plant Arabidopsis thaliana. Expression profiling of 31 VqSTS genes from Vitis quinquangularis revealed that VqSTS21 was up-regulated in response to powdery mildew (PM infection. To provide a deeper understanding of the function of this gene, we cloned the full-length coding sequence of VqSTS21 and overexpressed it in Arabidopsis thaliana via Agrobacterium-mediated transformation. The resulting VqSTS21 Arabidopsis lines produced trans-piceid rather than resveratrol as their main stilbenoid product and exhibited improved disease resistance to PM and Pseudomonas syringae pv. tomato DC3000, but displayed increased susceptibility to Botrytis cinerea. In addition, transgenic Arabidopsis lines were found to confer tolerance to salt and drought stress from seed germination through plant maturity. Intriguingly, qPCR assays of defense-related genes involved in salicylic acid, jasmonic acid, and abscisic acid-induced signaling pathways in these transgenic lines suggested that VqSTS21 plays a role in various phytohormone-related pathways, providing insight into the mechanism behind VqSTS21-mediated resistance to biotic and abiotic stress.

  12. Involvement of the salicylic acid signaling pathway in the systemic resistance induced in Arabidopsis by plant growth-promoting fungus Fusarium equiseti GF19-1.

    Science.gov (United States)

    Kojima, Hanae; Hossain, Md Motaher; Kubota, Mayumi; Hyakumachi, Mitsuro

    2013-01-01

    Plant growth-promoting fungi (PGPF) are effective biocontrol agents for a number of soil-borne diseases and are known for their ability to trigger induced systemic resistance (ISR). In this study, we investigated the mechanisms triggered by PGPF Fusarium equiseti GF19-1, which is known to increase pathogen resistance in plants, by using GF19-1 spores and the culture filtrate (CF) to treat the roots of Arabidopsis thaliana. Subsequently, the leaves were challenged with Pseudomonas syringae pv tomato DC3000 (Pst) bacteria. Arabidopsis plants treated with GF19-1 spores or the CF elicited ISR against the Pst pathogen, resulting in a restriction of disease severity and suppression of pathogen proliferation. Examination of ISR in various signaling mutants and transgenic plants showed that GF19-1-induced protection was observed in the jasmonate response mutant jar1 and the ethylene response mutant etr1, whereas it was blocked in Arabidopsis plants expressing the NahG transgene or demonstrating a disruption of the NPR1 gene (npr1). Analysis of systemic gene expression revealed that GF19-1 modulates the expression of salicylic acid (SA)-responsive PR-1, PR-2, and PR-5 genes. Moreover, transient accumulation of SA was observed in GF19-1-treated plant, whereas the level was further enhanced after Pst infection of GF19-1-pretreated plants, indicating that accumulation of SA was potentiated when Arabidopsis plants were primed for disease resistance by GF19-1. In conclusion, these findings imply that the induced protective effect conferred by F. equiseti GF19-1 against the leaf pathogen Pst requires responsiveness to an SA-dependent pathway.

  13. Expression of the Grape VqSTS21 Gene in Arabidopsis Confers Resistance to Osmotic Stress and Biotrophic Pathogens but Not Botrytis cinerea

    Science.gov (United States)

    Huang, Li; Zhang, Songlin; Singer, Stacy D.; Yin, Xiangjing; Yang, Jinhua; Wang, Yuejin; Wang, Xiping

    2016-01-01

    Stilbene synthase (STS) is a key gene in the biosynthesis of various stilbenoids, including resveratrol and its derivative glucosides (such as piceid), that has been shown to contribute to disease resistance in plants. However, the mechanism behind such a role has yet to be elucidated. Furthermore, the function of STS genes in osmotic stress tolerance remains unclear. As such, we sought to elucidate the role of STS genes in the defense against biotic and abiotic stress in the model plant Arabidopsis thaliana. Expression profiling of 31 VqSTS genes from Vitis quinquangularis revealed that VqSTS21 was up-regulated in response to powdery mildew (PM) infection. To provide a deeper understanding of the function of this gene, we cloned the full-length coding sequence of VqSTS21 and overexpressed it in Arabidopsis thaliana via Agrobacterium-mediated transformation. The resulting VqSTS21 Arabidopsis lines produced trans-piceid rather than resveratrol as their main stilbenoid product and exhibited improved disease resistance to PM and Pseudomonas syringae pv. tomato DC3000, but displayed increased susceptibility to Botrytis cinerea. In addition, transgenic Arabidopsis lines were found to confer tolerance to salt and drought stress from seed germination through plant maturity. Intriguingly, qPCR assays of defense-related genes involved in salicylic acid, jasmonic acid, and abscisic acid-induced signaling pathways in these transgenic lines suggested that VqSTS21 plays a role in various phytohormone-related pathways, providing insight into the mechanism behind VqSTS21-mediated resistance to biotic and abiotic stress. PMID:27695466

  14. EDS1, an essential component of R gene-mediated disease resistance in Arabidopsis has homology to eukaryotic lipases.

    Science.gov (United States)

    Falk, A; Feys, B J; Frost, L N; Jones, J D; Daniels, M J; Parker, J E

    1999-03-16

    A major class of plant disease resistance (R) genes encodes leucine-rich-repeat proteins that possess a nucleotide binding site and amino-terminal similarity to the cytoplasmic domains of the Drosophila Toll and human IL-1 receptors. In Arabidopsis thaliana, EDS1 is indispensable for the function of these R genes. The EDS1 gene was cloned by targeted transposon tagging and found to encode a protein that has similarity in its amino-terminal portion to the catalytic site of eukaryotic lipases. Thus, hydrolase activity, possibly on a lipid-based substrate, is anticipated to be central to EDS1 function. The predicted EDS1 carboxyl terminus has no significant sequence homologies, although analysis of eight defective eds1 alleles reveals it to be essential for EDS1 function. Two plant defense pathways have been defined previously that depend on salicylic acid, a phenolic compound, or jasmonic acid, a lipid-derived molecule. We examined the expression of EDS1 mRNA and marker mRNAs (PR1 and PDF1.2, respectively) for these two pathways in wild-type and eds1 mutant plants after different challenges. The results suggest that EDS1 functions upstream of salicylic acid-dependent PR1 mRNA accumulation and is not required for jasmonic acid-induced PDF1.2 mRNA expression.

  15. Arabidopsis COPPER MODIFIED RESISTANCE1/PATRONUS1 is essential for growth adaptation to stress and required for mitotic onset control.

    Science.gov (United States)

    Juraniec, Michal; Heyman, Jefri; Schubert, Veit; Salis, Pietrino; De Veylder, Lieven; Verbruggen, Nathalie

    2016-01-01

    The mitotic checkpoint (MC) guards faithful sister chromatid segregation by monitoring the attachment of spindle microtubules to the kinetochores. When chromosome attachment errors are detected, MC delays the metaphase-to-anaphase transition through the inhibition of the anaphase-promoting complex/cyclosome (APC/C) ubiquitin ligase. In contrast to yeast and mammals, our knowledge on the proteins involved in MC in plants is scarce. Transient synchronization of root tips as well as promoter-reporter gene fusions were performed to analyze temporal and spatial expression of COPPER MODIFIED RESISTANCE1/PATRONUS1 (CMR1/PANS1) in developing Arabidopsis thaliana seedlings. Functional analysis of the gene was carried out, including CYCB1;2 stability in CMR1/PANS1 knockout and overexpressor background as well as metaphase-anaphase chromosome status. CMR1/PANS1 is transcriptionally active during M phase. Its deficiency provokes premature cell cycle exit and in consequence a rapid consumption of the number of meristematic cells in particular under stress conditions that are known to affect spindle microtubules. Root growth impairment is correlated with a failure to delay the onset of anaphase, resulting in anaphase bridges and chromosome missegregation. CMR1/PANS1 overexpression stabilizes the mitotic CYCB1;2 protein. Likely, CMR1/PANS1 coordinates mitotic cell cycle progression by acting as an APC/C inhibitor and plays a key role in growth adaptation to stress.

  16. Resistance of Arabidopsis thaliana L. photosynthetic apparatus to UV-B is reduced by deficit of phytochromes B and A.

    Science.gov (United States)

    Khudyakova, Aleksandra Yu; Kreslavski, Vladimir D; Shirshikova, Galina N; Zharmukhamedov, Sergey K; Kosobryukhov, Anatoly A; Allakhverdiev, Suleyman I

    2017-03-01

    The photosynthetic responses of 25-day-old Arabidopsis phyA phyB double mutant (DM) compared with the wild type (WT) to UV-B radiation (1Wm(-2), 30min) were investigated. UV-B irradiation led to reduction of photosystem 2 (PS-2) activity and the photosynthetic rate. In plants grown under both white and red light (λm - 660nm) the reduction was greater in DM plants compared to the WT. Without UV-B irradiation a decrease in PS-2 activity was observed in DM grown under RL only. It is assumed that the lower content of UV-absorbing pigments and carotenoids observed in DM may be one of the reasons of reduced PS-2 resistance to UV-B. Higher decrease in activities under UV in DM plants grown under RL compared to DM plants grown under white light is likely due to the lack of activity of cryptochromes in plants grown under red light. Rates of post-stress recovery of photosynthetic activity of DM compared with WT plants under white and red light of low intensity were studied. Almost complete recovery of the activity was found which was not observed under dark conditions and in the presence of a protein synthesis inhibitor, chloramphenicol. It is assumed that phytochrome system participates in stress-protective mechanisms of the photosynthetic apparatus to UV-radiation.

  17. Ectopic Expression in Arabidopsis thaliana of an NB-ARC Encoding Putative Disease Resistance Gene from Wild Chinese Vitis pseudoreticulata Enhances Resistance to Phytopathogenic Fungi and Bacteria

    Directory of Open Access Journals (Sweden)

    Zhifeng eWen

    2015-12-01

    Full Text Available Plant resistance proteins mediate pathogen recognition and activate innate immune responses to restrict pathogen proliferation. One common feature of these proteins is an NB-ARC domain. In this study, we characterized a gene encoding a protein with an NB-ARC domain from wild Chinese grapevine Vitis pseudoreticulata accession Baihe-35-1, which was identified in a transcriptome analysis of the leaves following inoculation with Erysiphe necator (Schw., a causal agent of powdery mildew. Transcript levels of this gene, designated VpCN (GenBank accession number KT265084, increased strongly after challenge of grapevine leaves with E. necator. The deduced amino acid sequence was predicted to contain an NB-ARC domain in the C-terminus and an RxCC-like domain similar to CC domain of Rx protein in the N-terminus. Ectopic expression of VpCN in Arabidopsis thaliana resulted in either a wild-type phenotype or a dwarf phenotype. The phenotypically normal transgenic A. thaliana showed enhance resistance to A. thaliana powdery mildew Golovinomyces cichoracearum, as well as to a virulent bacterial pathogen Pseudomonas syringae pv. tomato DC3000. Moreover, promoter::GUS (β-glucuronidase analysis revealed that powdery mildew infection induced the promoter activity of VpCN in grapevine leaves. Finally, a promoter deletion analysis showed that TC rich repeat elements likely play an important role in the response to E. necator infection. Taken together, our results suggest that VpCN contribute to powdery mildew disease resistant in grapevine.

  18. The Arabidopsis downy mildew resistance gene, RPP13-Nd, functions independently of NDR1 and EDS1 and does not require the accumulation of salicylic acid.

    Science.gov (United States)

    Bittner-Eddy, P D; Beynon, J L

    2001-03-01

    RPP13-Nd-mediated resistance prevents parasitism by five isolates of Peronospora parasitica (At) in a transgenic Arabidopsis. Columbia background. We tested the effect of a number of known disease resistance mutations on the RPP13-Nd function and found that resistance remained unaltered in plants carrying mutations in either EDS1 or NDR1 and in double ndr1-1/eds1-2 mutant lines. Furthermore, we found that pbs2, pad4-1, npr1-1, and rps5-1, which compromise resistance to a number of P. parasitica (At) isolates, had no affect on RPP13-Nd function. In addition, RPP13-Nd-mediated resistance remained unchanged in a background of salicylic acid depletion (nahG). We conclude that RPP13-Nd is the first Arabidopsis R gene product reported to act via a novel signaling pathway that is independent of salicylic acid-mediated responses and is completely independent of NDR1 and EDS1.

  19. Ectopic expression of ubiquitin-conjugating enzyme gene from wild rice, OgUBC1, confers resistance against UV-B radiation and Botrytis infection in Arabidopsis thaliana

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, En Hee; Pak, Jung Hun; Kim, Mi Jin; Kim, Hye Jeong [Department of Genetic Engineering, Dong-A University, Busan 604-714 (Korea, Republic of); Shin, Sang Hyun [National Crop Experiment Station, Rural Development Administration, Suwon 441-100 (Korea, Republic of); Lee, Jai Heon; Kim, Doh Hoon; Oh, Ju Sung [Department of Genetic Engineering, Dong-A University, Busan 604-714 (Korea, Republic of); Oh, Boung-Jun [BioControl Center, Jeonnam 516-942 (Korea, Republic of); Jung, Ho Won, E-mail: hwjung@dau.ac.kr [Department of Genetic Engineering, Dong-A University, Busan 604-714 (Korea, Republic of); Chung, Young Soo, E-mail: chungys@dau.ac.kr [Department of Genetic Engineering, Dong-A University, Busan 604-714 (Korea, Republic of)

    2012-10-19

    Highlights: Black-Right-Pointing-Pointer We isolated a novel E2 ubiquitin-conjugating enzyme from leaves of wild rice plants. Black-Right-Pointing-Pointer The OgUBC1 was highly expressed in leaves treated with SA and UV-B radiation. Black-Right-Pointing-Pointer The recombinant OgUBC1 has an enzymatic activity of E2 in vitro. Black-Right-Pointing-Pointer The OgUBC1 could protect disruption of plant cells by UV-B radiation. Black-Right-Pointing-Pointer OgUBC1 confers disease resistance and UV-B tolerance in transgenic Arabidopsis plants. -- Abstract: A previously unidentified gene encoding ubiquitin-conjugating enzyme was isolated from leaves of wild rice plant treated with wounding and microbe-associated molecular patterns. The OgUBC1 gene was composed of 148 amino acids and contained a typical active site and 21 ubiquitin thioester intermediate interaction residues and 4 E3 interaction residues. Both exogenous application of salicylic acid and UV-B irradiation triggered expression of OgUBC1 in leaves of wild rice. Recombinant OgUBC1 proteins bound to ubiquitins in vitro, proposing that the protein might act as E2 enzyme in planta. Heterologous expression of the OgUBC1 in Arabidopsis thaliana protected plants from cellular damage caused by an excess of UV-B radiation. A stable expression of chalcone synthase gene was detected in leaves of OgUBC1-expressing Arabidopsis, resulting in producing higher amounts of anthocyanin than those in wild-type Col-0 plants. Additionally, both pathogenesis-related gene1 and 5 were transcribed in the transgenic Arabidopsis in the absence of pathogen infection. The OgUBC1-expressing plants were resistant to the infection of Botrytis cinerea. Taken together, we suggested that the OgUBC1 is involved in ubiquitination process important for cellular response against biotic and abiotic stresses in plants.

  20. Interfamily Transfer of Tomato Ve1 Mediates Verticillium Resistance in Arabidopsis

    NARCIS (Netherlands)

    Fradin, E.F.; Abd-El-Haliem, A.; Masini, L.; Berg, van den G.C.M.; Joosten, M.H.A.J.; Thomma, B.P.H.J.

    2011-01-01

    Vascular wilts caused by soil-borne fungal species of the Verticillium genus are devastating plant diseases. The most common species, Verticillium dahliae and Verticillium albo-atrum, have broad host ranges and are notoriously difficult to control. Therefore, genetic resistance is the preferred meth

  1. Thirty-seven transcription factor genes differentially respond to a harpin protein and affect resistance to the green peach aphid in Arabidopsis

    Indian Academy of Sciences (India)

    Ruoxue Liu; Beibei Lü; Xiaomeng Wang; Chunling Zhang; Shuping Zhang; Jun Qian; Lei Chen; Haojie Shi; Hansong Dong

    2010-09-01

    The harpin protein HrpNEa induces Arabidopsis resistance to the green peach aphid by activating the ethylene signalling pathway and by recruiting EIN2, an essential regulator of ethylene signalling, for a defence response in the plant. We investigated 37 ethylene-inducible Arabidopsis transcription factor genes for their effects on the activation of ethylene signalling and insect defence. Twenty-eight of the 37 genes responded to both ethylene and HrpNEa, and showed either increased or inhibited transcription, while 18 genes showed increased transcription not only by ethylene but also by HrpNEa. In response to HrpNEa, transcription levels of 22 genes increased, with AtMYB44 being the most inducible, six genes had decreased transcript levels, and nine remained unchanged. When Arabidopsis mutants previously generated by mutagenicity at the 37 genes were surveyed, 24 mutants were similar to the wild type plant while four mutants were more resistant and nine mutants were more susceptible than wild type to aphid infestation. Aphid-susceptible mutants showed a greater susceptibility for atmyb15, atmyb38 and atmyb44, which were generated previously by T-DNA insertion into the exon region of AtMYB15 and the promoter regions of AtMYB38 and AtMYB44. The atmyb44 mutant was the most susceptible to aphid infestation and most compromised in induced resistance. Resistance accompanied the expression of PDF1.2, an ethylene signalling marker gene that requires EIN2 for transcription in wild type but not in atmyb15, atmyb38, and atmyb44, suggesting a disruption of ethylene signalling in the mutants. However, only atmyb44 incurred an abrogation in induced EIN2 expression, suggesting a close relationship between AtMYB44 and EIN2.

  2. Silicon-mediated resistance of Arabidopsis against powdery mildew involves mechanisms other than the salicylic acid (SA)-dependent defence pathway.

    Science.gov (United States)

    Vivancos, Julien; Labbé, Caroline; Menzies, James G; Bélanger, Richard R

    2015-08-01

    On absorption by plants, silicon (Si) offers protection against many fungal pathogens, including powdery mildews. The mechanisms by which Si exerts its prophylactic role remain enigmatic, although a prevailing hypothesis suggests that Si positively influences priming. Attempts to decipher Si properties have been limited to plants able to absorb Si, which excludes the model plant Arabidopsis because it lacks Si influx transporters. In this work, we were able to engineer Arabidopsis plants with an Si transporter from wheat (TaLsi1) and to exploit mutants (pad4 and sid2) deficient in salicylic acid (SA)-dependent defence responses to study their phenotypic response and changes in defence expression against Golovinomyces cichoracearum (Gc) following Si treatment. Our results showed that TaLsi1 plants contained significantly more Si and were significantly more resistant to Gc infection than control plants when treated with Si, the first such demonstration in a plant transformed with a heterologous Si transporter. The resistant plants accumulated higher levels of SA and expressed higher levels of transcripts encoding defence genes, thus suggesting a role for Si in the process. However, TaLsi1 pad4 and TaLsi1 sid2 plants were also more resistant to Gc than were pad4 and sid2 plants following Si treatment. Analysis of the resistant phenotypes revealed a significantly reduced production of SA and expression of defence genes comparable with susceptible controls. These results indicate that Si contributes to Arabidopsis defence priming following pathogen infection, but highlight that Si will confer protection even when priming is altered. We conclude that Si-mediated protection involves mechanisms other than SA-dependent defence responses.

  3. Modulation of auxin content in Arabidopsis confers improved drought stress resistance.

    Science.gov (United States)

    Shi, Haitao; Chen, Li; Ye, Tiantian; Liu, Xiaodong; Ding, Kejian; Chan, Zhulong

    2014-09-01

    Auxin is a well-known plant phytohormone that is involved in multiple plant growth processes and stress responses. In this study, auxin response was significantly modulated under drought stress condition. The iaaM-OX transgenic lines with higher endogenous indole-3-acetic acid (IAA) level and IAA pre-treated wild type (WT) plants exhibited enhanced drought stress resistance, while the yuc1yuc2yuc6 triple mutants with lower endogenous IAA level showed decreased stress resistance in comparison to non-treated WT plants. Additionally, endogenous and exogenous auxin positively modulated the expression levels of multiple abiotic stress-related genes (RAB18, RD22, RD29A, RD29B, DREB2A, and DREB2B), and positively affected reactive oxygen species (ROS) metabolism and underlying antioxidant enzyme activities. Moreover, auxin significantly modulated some carbon metabolites including amino acids, organic acids, sugars, sugar alcohols and aromatic amines. Notably, endogenous and exogenous auxin positively modulated root architecture especially the lateral root number. Taken together, this study demonstrated that auxin might participate in the positive regulation of drought stress resistance, through regulation of root architecture, ABA-responsive genes expression, ROS metabolism, and metabolic homeostasis, at least partially.

  4. A synthetic antimicrobial peptide BTD-S expressed in Arabidopsis thaliana confers enhanced resistance to Verticillium dahliae.

    Science.gov (United States)

    Li, Feng; Shen, Hao; Wang, Ming; Fan, Kai; Bibi, Noreen; Ni, Mi; Yuan, Shuna; Wang, Xuede

    2016-08-01

    BTD-S is a synthetic non-cyclic θ-defensin derivative which was previously designed in our laboratory based on baboon θ-defensins (BTDs). It shows robust antimicrobial activity against economically important phytopathogen, Verticillium dahliae. Here, we deduced the coding nucleotide sequence of BTD-S and introduced the gene into wild-type (ecotype Columbia-0) Arabidopsis thaliana plants. Results demonstrated that BTD-S-transgenic lines displayed in bioassays inhibitory effects on the growth of V. dahliae in vivo and in vitro. Based on symptom severity, enhanced resistance was found in a survey of BTD-S-transgenic lines. Besides, crude protein extracts from root tissues of BTD-S-transformed plants significantly restricted the growth of fungal hyphae and the germination of conidia. Also, fungal biomass over time determined by real-time PCR demonstrated the overgrowth of V. dahliae in wild-type plants 2-3 weeks after inoculation, while almost no fungal DNA was detected in aerial tissues of their transgenic progenitors. The result suggested that fungus failed to invade and progress acropetally up to establish a systemic infection in BTD-S-transgenic plants. Moreover, the assessment of basal defense responses was performed in the leaves of WT and BTD-S-transgenic plants. The mitigated oxidative stress and low antioxidase level in BTD-S-transgenic plants revealed that BTD-S acts via permeabilizing target microbial membranes, which is in a category different from hypersensitive response-dependent defense. Taken together, our results demonstrate that BTD-S is a promising gene to be explored for transgenic engineering for plant protection against Verticillium wilt.

  5. The Arabidopsis Tellurite resistance C protein together with ALB3 is involved in photosystem II protein synthesis.

    Science.gov (United States)

    Schneider, Anja; Steinberger, Iris; Strissel, Henning; Kunz, Hans-Henning; Manavski, Nikolay; Meurer, Jörg; Burkhard, Gabi; Jarzombski, Sabine; Schünemann, Danja; Geimer, Stefan; Flügge, Ulf-Ingo; Leister, Dario

    2014-04-01

    Assembly of photosystem II (PSII) occurs sequentially and requires several auxiliary proteins, such as ALB3 (ALBINO3). Here, we describe the role of the Arabidopsis thaliana thylakoid membrane protein Tellurite resistance C (AtTerC) in this process. Knockout of AtTerC was previously shown to be seedling-lethal. This phenotype was rescued by expressing TerC fused C-terminally to GFP in the terc-1 background, and the resulting terc-1TerC- GFP line and an artificial miRNA-based knockdown allele (amiR-TerC) were used to analyze the TerC function. The alterations in chlorophyll fluorescence and thylakoid ultrastructure observed in amiR-TerC plants and terc-1TerC- GFP were attributed to defects in PSII. We show that this phenotype resulted from a reduction in the rate of de novo synthesis of PSII core proteins, but later steps in PSII biogenesis appeared to be less affected. Yeast two-hybrid assays showed that TerC interacts with PSII proteins. In particular, its interaction with the PSII assembly factor ALB3 has been demonstrated by co-immunoprecipitation. ALB3 is thought to assist in incorporation of CP43 into PSII via interaction with Low PSII Accumulation2 (LPA2) Low PSII Accumulation3 (LPA3). Homozygous lpa2 mutants expressing amiR-TerC displayed markedly exacerbated phenotypes, leading to seedling lethality, indicating an additive effect. We propose a model in which TerC, together with ALB3, facilitates de novo synthesis of thylakoid membrane proteins, for instance CP43, at the membrane insertion step.

  6. AtMIN7 mediated disease resistance to Pseudomonas syringae in Arabidopsis

    Science.gov (United States)

    He, Sheng Yang; Nomura, Kinya

    2011-07-26

    The present invention relates to compositions and methods for enhancing plant defenses against pathogens. More particularly, the invention relates to enhancing plant immunity against bacterial pathogens, wherein AtMIN7 mediated protection is enhanced and/or there is a decrease in activity of an AtMIN7 associated virulence protein such as a Pseudomonas syringae pv. tomato DC3000 HopM1. Reagents of the present invention provide a means of studying cellular trafficking while formulations of the present inventions provide increased pathogen resistance in plants.

  7. Iron-regulated metabolites produced by Pseudomonas fluorescens WCS374r are not required for eliciting induced systemic resistance against Pseudomonas syringae pv. tomato in Arabidopsis.

    Science.gov (United States)

    Djavaheri, Mohammad; Mercado-Blanco, Jesús; Versluis, C; Meyer, J-M; Loon, L C; Bakker, Peter A H M

    2012-09-01

    The plant growth-promoting rhizobacterium Pseudomonas fluorescens WCS374r produces several iron-regulated metabolites, including the fluorescent siderophore pseudobactin (Psb374), salicylic acid (SA), and pseudomonine (Psm), a siderophore that contains a SA moiety. After purification of Psb374 from culture supernatant of WCS374r, its structure was determined following isoelectrofocusing and tandem mass spectrometry, and found to be identical to the fluorescent siderophore produced by P. fluorescens ATCC 13525. To study the role of SA and Psm production in colonization of Arabidopsis thaliana roots and in induced systemic resistance (ISR) against Pseudomonas syringae pv. tomato (Pst) by strain WCS374r, mutants disrupted in the production of these metabolites were obtained by homologous recombination. These mutants were further subjected to transposon Tn5 mutagenesis to generate mutants also deficient in Psb374 production. The mutants behaved similar to the wild type in both their Arabidopsis rhizosphere-colonizing capacity and their ability to elicit ISR against Pst. We conclude that Psb374, SA, and Psm production by P. fluorescens WCS374r are not required for eliciting ISR in Arabidopsis.

  8. Transport of antimony salts by Arabidopsis thaliana protoplasts over-expressing the human multidrug resistance-associated protein 1 (MRP1/ABCC1).

    Science.gov (United States)

    Gayet, Landry; Picault, Nathalie; Cazalé, Anne-Claire; Beyly, Audrey; Lucas, Philippe; Jacquet, Hélène; Suso, Henri-Pierre; Vavasseur, Alain; Peltier, Gilles; Forestier, Cyrille

    2006-12-22

    ABC transporters from the multidrug resistance-associated protein (MRP) subfamily are glutathione S-conjugate pumps exhibiting a broad substrate specificity illustrated by numerous xenobiotics, such as anticancer drugs, herbicides, pesticides and heavy metals. The engineering of MRP transporters into plants might be interesting either to reduce the quantity of xenobiotics taken up by the plant in the context of "safe-food" strategies or, conversely, in the development of phytoremediation strategies in which xenobiotics are sequestered in the vacuolar compartment. In this report, we obtained Arabidopsis transgenic plants overexpressing human MRP1. In these plants, expression of MRP1 did not increase plant resistance to antimony salts (Sb(III)), a classical glutathione-conjugate substrate of MRP1. However, the transporter was fully translated in roots and shoots, and targeted to the plasma membrane. In order to investigate the functionality of MRP1 in Arabidopsis, mesophyll cell protoplasts (MCPs) were isolated from transgenic plants and transport activities were measured by using calcein or Sb(III) as substrates. Expression of MRP1 at the plasma membrane was correlated with an increase in the MCPs resistance to Sb(III) and a limitation of the metalloid content in the protoplasts due to an improvement in Sb(III) efflux. Moreover, Sb(III) transport was sensitive to classical inhibitors of the human MRP1, such as MK571 or glibenclamide. These results demonstrate that a human ABC transporter can be functionally introduced in Arabidopsis, which might be useful, with the help of stronger promoters, to reduce the accumulation of xenobiotics in plants, such as heavy metals from multi-contaminated soils.

  9. Bacillus cereus AR156 primes induced systemic resistance by suppressing miR825/825? and activating defense-related genes in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Dongdong Niu; Hongwei Zhao; Jing Xia; Chunhao Jiang; Beibei Qi; Xiaoyu Ling; Siyuan Lin; Weixiong Zhang; Jianhua Guo; Hailing Jin

    2016-01-01

    Small RNAs play an important role in plant immune responses. However, their regulatory function in induced systemic resistance (ISR) is nascent. Bacillus cereus AR156 is a plant growth-promoting rhizobacterium that induces ISR in Arabidopsis against bacterial infection. Here, by comparing small RNA profiles of Pseudomonas syringae pv. tomato (Pst) DC3000-infected Arabidopsis with and without AR156 pretreatment, we identified a group of Arabidopsis microRNAs (miRNAs) that are differentially regulated by AR156 pretreatment. miR825 and miR825? are two miRNA generated from a single miRNA gene. Northern blot analysis indicated that they were significantly downregulated in Pst DC3000-infected plants pretreated with AR156, in contrast to the plants without AR156 pretreatment. miR825 targets two ubiquitin-protein ligases, while miR825? targets toll-interleukin-like receptor (TIR)-nucleotide binding site (NBS) and leucine-rich repeat (LRR) type resistance (R) genes. The expression of these target genes negatively correlated with the expression of miR825 and miR825?. Moreover, transgenic plants showing reduced expression of miR825 and miR825? displayed enhanced resistance to Pst DC3000 infection, whereas transgenic plants overexpressing miR825 and miR825? were more susceptible. Taken together, our data indicates that Bacillus cereus AR156 pretreatment primes ISR to Pst infection by suppressing miR825 and miR825? and activating the defense related genes they targeted.

  10. Bacillus cereus AR156 primes induced systemic resistance by suppressing miR825/825* and activating defense-related genes in Arabidopsis.

    Science.gov (United States)

    Niu, Dongdong; Xia, Jing; Jiang, Chunhao; Qi, Beibei; Ling, Xiaoyu; Lin, Siyuan; Zhang, Weixiong; Guo, Jianhua; Jin, Hailing; Zhao, Hongwei

    2016-04-01

    Small RNAs play an important role in plant immune responses. However, their regulatory function in induced systemic resistance (ISR) is nascent. Bacillus cereus AR156 is a plant growth-promoting rhizobacterium that induces ISR in Arabidopsis against bacterial infection. Here, by comparing small RNA profiles of Pseudomonas syringae pv. tomato (Pst) DC3000-infected Arabidopsis with and without AR156 pretreatment, we identified a group of Arabidopsis microRNAs (miRNAs) that are differentially regulated by AR156 pretreatment. miR825 and miR825* are two miRNA generated from a single miRNA gene. Northern blot analysis indicated that they were significantly downregulated in Pst DC3000-infected plants pretreated with AR156, in contrast to the plants without AR156 pretreatment. miR825 targets two ubiquitin-protein ligases, while miR825* targets toll-interleukin-like receptor (TIR)-nucleotide binding site (NBS) and leucine-rich repeat (LRR) type resistance (R) genes. The expression of these target genes negatively correlated with the expression of miR825 and miR825*. Moreover, transgenic plants showing reduced expression of miR825 and miR825* displayed enhanced resistance to Pst DC3000 infection, whereas transgenic plants overexpressing miR825 and miR825* were more susceptible. Taken together, our data indicates that Bacillus cereus AR156 pretreatment primes ISR to Pst infection by suppressing miR825 and miR825* and activating the defense related genes they targeted.

  11. Heterologous expression of a Tpo1 homolog from Arabidopsis thaliana confers resistance to the herbicide 2,4-D and other chemical stresses in yeast.

    Science.gov (United States)

    Cabrito, Tânia R; Teixeira, Miguel C; Duarte, Alexandra A; Duque, Paula; Sá-Correia, Isabel

    2009-10-01

    The understanding of the molecular mechanisms underlying acquired herbicide resistance is crucial in dealing with the emergence of resistant weeds. Saccharomyces cerevisiae has been used as a model system to gain insights into the mechanisms underlying resistance to the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). The TPO1 gene, encoding a multidrug resistance (MDR) plasma membrane transporter of the major facilitator superfamily (MFS), was previously found to confer resistance to 2,4-D in yeast and to be transcriptionally activated in response to the herbicide. In this work, we demonstrate that Tpo1p is required to reduce the intracellular concentration of 2,4-D. ScTpo1p homologs encoding putative plasma membrane MFS transporters from the plant model Arabidopsis thaliana were analyzed for a possible role in 2,4-D resistance. At5g13750 was chosen for further analysis, as its transcript levels were found to increase in 2,4-D stressed plants. The functional heterologous expression of this plant open reading frame in yeast was found to confer increased resistance to the herbicide in Deltatpo1 and wild-type cells, through the reduction of the intracellular concentration of 2,4-D. Heterologous expression of At5g13750 in yeast also leads to increased resistance to indole-3-acetic acid (IAA), Al(3+) and Tl(3+). At5g13750 is the first plant putative MFS transporter to be suggested as possibly involved in MDR.

  12. Contrasting Roles of the Apoplastic Aspartyl Protease APOPLASTIC, ENHANCED DISEASE SUSCEPTIBILITY1-DEPENDENT1 and LEGUME LECTIN-LIKE PROTEIN1 in Arabidopsis Systemic Acquired Resistance.

    Science.gov (United States)

    Breitenbach, Heiko H; Wenig, Marion; Wittek, Finni; Jordá, Lucia; Maldonado-Alconada, Ana M; Sarioglu, Hakan; Colby, Thomas; Knappe, Claudia; Bichlmeier, Marlies; Pabst, Elisabeth; Mackey, David; Parker, Jane E; Vlot, A Corina

    2014-04-22

    Systemic acquired resistance (SAR) is an inducible immune response that depends on ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1). Here, we show that Arabidopsis (Arabidopsis thaliana) EDS1 is required for both SAR signal generation in primary infected leaves and SAR signal perception in systemic uninfected tissues. In contrast to SAR signal generation, local resistance remains intact in eds1 mutant plants in response to Pseudomonas syringae delivering the effector protein AvrRpm1. We utilized the SAR-specific phenotype of the eds1 mutant to identify new SAR regulatory proteins in plants conditionally expressing AvrRpm1. Comparative proteomic analysis of apoplast-enriched extracts from AvrRpm1-expressing wild-type and eds1 mutant plants led to the identification of 12 APOPLASTIC, EDS1-DEPENDENT (AED) proteins. The genes encoding AED1, a predicted aspartyl protease, and another AED, LEGUME LECTIN-LIKE PROTEIN1 (LLP1), were induced locally and systemically during SAR signaling and locally by salicylic acid (SA) or its functional analog, benzo 1,2,3-thiadiazole-7-carbothioic acid S-methyl ester. Because conditional overaccumulation of AED1-hemagglutinin inhibited SA-induced resistance and SAR but not local resistance, the data suggest that AED1 is part of a homeostatic feedback mechanism regulating systemic immunity. In llp1 mutant plants, SAR was compromised, whereas the local resistance that is normally associated with EDS1 and SA as well as responses to exogenous SA appeared largely unaffected. Together, these data indicate that LLP1 promotes systemic rather than local immunity, possibly in parallel with SA. Our analysis reveals new positive and negative components of SAR and reinforces the notion that SAR represents a distinct phase of plant immunity beyond local resistance.

  13. Downy mildew (Peronospora parasitica) resistance genes in Arabidopsis vary in functional requirements for NDR1, EDS1, NPR1 and salicylic acid accumulation.

    Science.gov (United States)

    McDowell, J M; Cuzick, A; Can, C; Beynon, J; Dangl, J L; Holub, E B

    2000-06-01

    To better understand the genetic requirements for R gene-dependent defense activation in Arabidopsis, we tested the effect of several defense response mutants on resistance specified by eight RPP genes (for resistance to Peronospora parasitica) expressed in the Col-0 background. In most cases, resistance was not suppressed by a mutation in the SAR regulatory gene NPR1 or by expression of the NahG transgene. Thus, salicylic acid accumulation and NPR1 function are not necessary for resistance mediated by these RPP genes. In addition, resistance conferred by two of these genes, RPP7 and RPP8, was not significantly suppressed by mutations in either EDS1 or NDR1. RPP7 resistance was also not compromised by mutations in EIN2, JAR1 or COI1 which affect ethylene or jasmonic acid signaling. Double mutants were therefore tested. RPP7 and RPP8 were weakly suppressed in an eds1-2/ndr1-1 background, suggesting that these RPP genes operate additively through EDS1, NDR1 and as-yet-undefined signaling components. RPP7 was not compromised in coi1/npr1 or coi1/NahG backgrounds. These observations suggest that RPP7 initiates resistance through a novel signaling pathway that functions independently of salicylic acid accumulation or jasmonic acid response components.

  14. Transcription factors WRKY70 and WRKY11 served as regulators in rhizobacterium Bacillus cereus AR156-induced systemic resistance to Pseudomonas syringae pv. tomato DC3000 in Arabidopsis.

    Science.gov (United States)

    Jiang, Chun-Hao; Huang, Zi-Yang; Xie, Ping; Gu, Chun; Li, Ke; Wang, Da-Chen; Yu, Yi-Yang; Fan, Zhi-Hang; Wang, Chun-Juan; Wang, Yun-Peng; Guo, Ya-Hui; Guo, Jian-Hua

    2016-01-01

    The activation of both the SA and JA/ETsignalling pathways may lead to more efficient general and broad resistance to Pst DC3000 by non-pathogenic rhizobacteria. However, the mechanisms that govern this simultaneous activation are unclear. Using Arabidopsis as a model system, two transcription factors, WRKY11 and WRKY70, were identified as important regulators involved in Induced Systemic Resistance (ISR) triggered by Bacillus cereus AR156. The results revealed that AR156 treatment significantly stimulated the transcription of WRKY70, but suppressed that of WRKY11 in Arabidopsis leaves. Furthermore, they were shown to be required for AR156 enhancing the activation of cellular defence responses and the transcription level of the plant defence response gene. Overexpression of the two transcription factors in Arabidopsis also showed that they were essential for AR156 to elicit ISR. AR156-triggered ISR was completely abolished in the double mutant of the two transcription factors, but still partially retained in the single mutants, indicating that the regulation of the two transcription factors depend on two different pathways. The target genes of the two transcription factors and epistasis analysis suggested that WRKY11 regulated AR156-triggered ISR through activating the JA signalling pathway, and WRKY70 regulated the ISR through activating the SA signalling pathway. In addition, both WRKY11 and WRKY70 modulated AR156-triggered ISR in a NPR1-dependent manner. In conclusion, WRKY11 and WRKY70 played an important role in regulating the signalling transduction pathways involved in AR156-triggered ISR. This study is the first to illustrate the mechanism by which a single rhizobacterium elicits ISR by simultaneously activating both the SA and JA/ET signalling pathways.

  15. Are bacterial volatile compounds poisonous odors to a fungal pathogen Botrytis cinerea, alarm signals to Arabidopsis seedlings for eliciting induced resistance, or both?

    Directory of Open Access Journals (Sweden)

    Choong-Min eRyu

    2016-02-01

    Full Text Available Biological control (biocontrol agents act on plants via numerous mechanisms, and can be used to protect plants from pathogens. Biocontrol agents can act directly as pathogen antagonists or competitors or indirectly to promote plant induced systemic resistance (ISR. Whether a biocontrol agent acts directly or indirectly depends on the specific strain and the pathosystem type. We reported previously that bacterial volatile organic compounds (VOCs are determinants for eliciting plant ISR. Emerging data suggest that bacterial VOCs also can directly inhibit fungal and plant growth. The aim of the current study was to differentiate direct and indirect mechanisms of bacterial VOC effects against Botrytis cinerea infection of Arabidopsis. Volatile emissions from Bacillus subtilis GB03 successfully protected Arabidopsis seedlings against B. cinerea. First, we investigated the direct effects of bacterial VOCs on symptom development and different phenological stages of B. cinerea including spore germination, mycelial attachment to the leaf surface, mycelial growth, and sporulation in vitro and in planta. Volatile emissions inhibited hyphal growth in a dose-dependent manner in vitro, and interfered with fungal attachment on the hydrophobic leaf surface. Second, the optimized bacterial concentration that did not directly inhibit fungal growth successfully protected Arabidopsis from fungal infection, which indicates that bacterial VOC-elicited plant ISR has a more important role in biocontrol than direct inhibition of fungal growth on Arabidopsis. We performed qRT-PCR to investigate the priming of the defense-related genes PR1, PDF1.2, and ChiB at 0, 12, 24, and 36 hours post-infection and 14 days after the start of plant exposure to bacterial VOCs. The results indicate that bacterial VOCs potentiate expression of PR1 and PDF1.2 but not ChiB, which stimulates SA- and JA-dependent signaling pathways in plant ISR and protects plants against pathogen

  16. Expression of an alfalfa (Medicago sativa L.) peroxidase gene in transgenic Arabidopsis thaliana enhances resistance to NaCl and H2O2.

    Science.gov (United States)

    Teng, K; Xiao, G Z; Guo, W E; Yuan, J B; Li, J; Chao, Y H; Han, L B

    2016-05-23

    Peroxidases (PODs) are enzymes that play important roles in catalyzing the reduction of H2O2 and the oxidation of various substrates. They function in many different and important biological processes, such as defense mechanisms, immune responses, and pathogeny. The POD genes have been cloned and identified in many plants, but their function in alfalfa (Medicago sativa L.) is not known, to date. Based on the POD gene sequence (GenBank accession No. L36157.1), we cloned the POD gene in alfalfa, which was named MsPOD. MsPOD expression increased with increasing H2O2. The gene was expressed in all of the tissues, including the roots, stems, leaves, and flowers, particularly in stems and leaves under light/dark conditions. A subcellular analysis showed that MsPOD was localized outside the cells. Transgenic Arabidopsis with MsPOD exhibited increased resistance to H2O2 and NaCl. Moreover, POD activity in the transgenic plants was significantly higher than that in wild-type Arabidopsis. These results show that MsPOD plays an important role in resistance to H2O2 and NaCl.

  17. Arabidopsis and Brachypodium distachyon transgenic plants expressing Aspergillus nidulans acetylesterases have decreased degree of polysaccharide acetylation and increased resistance to pathogens.

    Science.gov (United States)

    Pogorelko, Gennady; Lionetti, Vincenzo; Fursova, Oksana; Sundaram, Raman M; Qi, Mingsheng; Whitham, Steven A; Bogdanove, Adam J; Bellincampi, Daniela; Zabotina, Olga A

    2013-05-01

    The plant cell wall has many significant structural and physiological roles, but the contributions of the various components to these roles remain unclear. Modification of cell wall properties can affect key agronomic traits such as disease resistance and plant growth. The plant cell wall is composed of diverse polysaccharides often decorated with methyl, acetyl, and feruloyl groups linked to the sugar subunits. In this study, we examined the effect of perturbing cell wall acetylation by making transgenic Arabidopsis (Arabidopsis thaliana) and Brachypodium (Brachypodium distachyon) plants expressing hemicellulose- and pectin-specific fungal acetylesterases. All transgenic plants carried highly expressed active Aspergillus nidulans acetylesterases localized to the apoplast and had significant reduction of cell wall acetylation compared with wild-type plants. Partial deacetylation of polysaccharides caused compensatory up-regulation of three known acetyltransferases and increased polysaccharide accessibility to glycosyl hydrolases. Transgenic plants showed increased resistance to the fungal pathogens Botrytis cinerea and Bipolaris sorokiniana but not to the bacterial pathogens Pseudomonas syringae and Xanthomonas oryzae. These results demonstrate a role, in both monocot and dicot plants, of hemicellulose and pectin acetylation in plant defense against fungal pathogens.

  18. Overexpression of Arabidopsis YUCCA6 in Potato Results in High-Auxin Developmental Phenotypes and Enhanced Resistance to Water Deficit

    Institute of Scientific and Technical Information of China (English)

    Jeong Im Kim; Dongwon Baek; Hyeong Cheol Park; Hyun Jin Chun; Dong-Ha Oh; Min Kyung Lee; Joon-Yung Cha

    2013-01-01

    Indole-3-acetic acid (IAA),a major plant auxin,is produced in both tryptophan-dependent and tryptophanindependent pathways.A major pathway in Arabidopsis thaliana generates IAA in two reactions from tryptophan.Step one converts tryptophan to indole-3-pyruvic acid (IPA) by tryptophan aminotransferases followed by a rate-limiting step converting IPA to IAA catalyzed by YUCCA proteins.We identified eight putative StYUC (Solanum tuberosum YUCCA)genes whose deduced amino acid sequences share 50%-70% identity with those of Arabidopsis YUCCA proteins.All include canonical,conserved YUCCA sequences:FATGY motif,FMO signature sequence,and FAD-binding and NADP-binding sequences.In addition,five genes were found with-50% amino acid sequence identity to Arabidopsis tryptophan aminotransferases.Transgenic potato (Solanum tuberosum cv.Jowon) constitutively overexpressing Arabidopsis AtYUC6 displayed high-auxin phenotypes such as narrow downward-curled leaves,increased height,erect stature,and longevity.Transgenic potato plants overexpressing AtYUC6 showed enhanced drought tolerance based on reduced water loss.The phenotype was correlated with reduced levels of reactive oxygen species in leaves.The results suggest a functional YUCCA pathway of auxin biosynthesis in potato that may be exploited to alter plant responses to the environment.

  19. Constitutive disease resistance requires EDS1 in the Arabidopsis mutants cpr1 and cpr6 and is partially EDS1-dependent in cpr5.

    Science.gov (United States)

    Clarke, J D; Aarts, N; Feys, B J; Dong, X; Parker, J E

    2001-05-01

    The systemic acquired resistance (SAR) response in Arabidopsis is characterized by the accumulation of salicylic acid (SA), expression of the pathogenesis-related (PR) genes, and enhanced resistance to virulent bacterial and oomycete pathogens. The cpr (constitutive expressor of PR genes) mutants express all three SAR phenotypes. In addition, cpr5 and cpr6 induce expression of PDF1.2, a defense-related gene associated with activation of the jasmonate/ethylene-mediated resistance pathways. cpr5 also forms spontaneous lesions. In contrast, the eds1 (enhanced disease susceptibility) mutation abolishes race-specific resistance conferred by a major subclass of resistance (R) gene products in response to avirulent pathogens. eds1 plants also exhibit increased susceptibility to virulent pathogens. Epistasis experiments were designed to explore the relationship between the cpr- and EDS1-mediated resistance pathways. We found that a null eds1 mutation suppresses the disease resistance phenotypes of both cpr1 and cpr6. In contrast, eds1 only partially suppresses resistance in cpr5, leading us to conclude that cpr5 expresses both EDS1-dependent and EDS1-independent components of plant disease resistance. Although eds1 does not prevent lesion formation on cpr5 leaves, it alters their appearance and reduces their spread. This phenotypic difference is associated with increased pathogen colonization of cpr5 eds1 plants compared to cpr5. The data allow us to place EDS1 as a necessary downstream component of cpr1- and cpr6-mediated responses, but suggest a more complex relationship between EDS1 and cpr5 in plant defense.

  20. A Rice Gene Homologous to Arabidopsis AGD2-LIKE DEFENSE1 Participates in Disease Resistance Response against Infection with Magnaporthe oryzae

    Directory of Open Access Journals (Sweden)

    Ga Young Jung

    2016-08-01

    Full Text Available ALD1 (ABERRANT GROWTH AND DEATH2 [AGD2]-LIKE DEFENSE1 is one of the key defense regulators in Arabidopsis thaliana and Nicotiana benthamiana. In these model plants, ALD1 is responsible for triggering basal defense response and systemic resistance against bacterial infection. As well ALD1 is involved in the production of pipecolic acid and an unidentified compound(s for systemic resistance and priming syndrome, respectively. These previous studies proposed that ALD1 is a potential candidate for developing genetically modified (GM plants that may be resistant to pathogen infection. Here we introduce a role of ALD1-LIKE gene of Oryza sativa, named as OsALD1, during plant immunity. OsALD1 mRNA was strongly transcribed in the infected leaves of rice plants by Magnaporthe oryzae, the rice blast fungus. OsALD1 proteins predominantly localized at the chloroplast in the plant cells. GM rice plants over-expressing OsALD1 were resistant to the fungal infection. The stable expression of OsALD1 also triggered strong mRNA expression of PATHOGENESIS-RELATED PROTEIN1 genes in the leaves of rice plants during infection. Taken together, we conclude that OsALD1 plays a role in disease resistance response of rice against the infection with rice blast fungus.

  1. A Rice Gene Homologous to Arabidopsis AGD2-LIKE DEFENSE1 Participates in Disease Resistance Response against Infection with Magnaporthe oryzae.

    Science.gov (United States)

    Jung, Ga Young; Park, Ju Yeon; Choi, Hyo Ju; Yoo, Sung-Je; Park, Jung-Kwon; Jung, Ho Won

    2016-08-01

    ALD1 (ABERRANT GROWTH AND DEATH2 [AGD2]-LIKE DEFENSE1) is one of the key defense regulators in Arabidopsis thaliana and Nicotiana benthamiana. In these model plants, ALD1 is responsible for triggering basal defense response and systemic resistance against bacterial infection. As well ALD1 is involved in the production of pipecolic acid and an unidentified compound(s) for systemic resistance and priming syndrome, respectively. These previous studies proposed that ALD1 is a potential candidate for developing genetically modified (GM) plants that may be resistant to pathogen infection. Here we introduce a role of ALD1-LIKE gene of Oryza sativa, named as OsALD1, during plant immunity. OsALD1 mRNA was strongly transcribed in the infected leaves of rice plants by Magnaporthe oryzae, the rice blast fungus. OsALD1 proteins predominantly localized at the chloroplast in the plant cells. GM rice plants over-expressing OsALD1 were resistant to the fungal infection. The stable expression of OsALD1 also triggered strong mRNA expression of PATHOGENESIS-RELATED PROTEIN1 genes in the leaves of rice plants during infection. Taken together, we conclude that OsALD1 plays a role in disease resistance response of rice against the infection with rice blast fungus.

  2. Arabidopsis TAF1 is an MRE11-interacting protein required for resistance to genotoxic stress and viability of the male gametophyte.

    Science.gov (United States)

    Waterworth, Wanda M; Drury, Georgina E; Blundell-Hunter, George; West, Christopher E

    2015-11-01

    Repair of DNA double-strand breaks (DSBs) by recombination pathways is essential for plant growth and fertility. The recombination endonuclease MRE11 plays important roles in sensing and repair of DNA DSBs. Here we demonstrate protein interaction between Arabidopsis MRE11 and the histone acetyltransferase TAF1, a TATA-binding protein Associated Factor (TAF) of the RNA polymerase II transcription initiation factor complex TFIID. Arabidopsis has two TAF1 homologues termed TAF1 and TAF1b and mutant taf1b lines are viable and fertile. In contrast, taf1 null mutations are lethal, demonstrating that TAF1 is an essential gene. Heterozygous taf1+/- plants display abnormal segregation of the mutant allele resulting from defects in pollen tube development, indicating that TAF1 is important for gamete viability. Characterization of an allelic series of taf1 lines revealed that hypomorphic mutants are viable but display developmental defects and reduced plant fertility. Hypersensitivity of taf1 mutants lacking the C-terminal bromodomain to X-rays and mitomycin C, but not to other forms of abiotic stress, established a specific role for TAF1 in plant DNA repair processes. Collectively these studies reveal a function for TAF1 in plant resistance to genotoxic stress, providing further insight into the molecular mechanisms of the DNA damage response in plants.

  3. The arabidopsis TIR-NB-LRR gene RAC1 confers resistance to Albugo candida (white rust) and is dependent on EDS1 but not PAD4.

    Science.gov (United States)

    Borhan, Mohammad H; Holub, Eric B; Beynon, Jim L; Rozwadowski, Kevin; Rimmer, S Roger

    2004-07-01

    Resistance to Albugo candida isolate Acem1 is conferred by a dominant gene, RAC1, in accession Ksk-1 of Arabidopsis thaliana. This gene was isolated by positional cloning and is a member of the Drosophila toll and mammalian interleukin-1 receptor (TIR) nucleotide-binding site leucine-rich repeat (NB-LRR) class of plant resistance genes. Strong identity of the TIR and NB domains was observed between the predicted proteins encoded by the Ksk-1 allele and the allele from an Acem1-susceptible accession Columbia (Col) (99 and 98%, respectively). However, major differences between the two predicted proteins occur within the LRR domain and mainly are confined to the beta-strand/beta-turn structure of the LRR. Both proteins contain 14 imperfect repeats. RAC1-mediated resistance was analyzed further using mutations in defense regulation, including: pad4-1, eds1-1, and NahG, in the presence of the RAC1 allele from Ksk-1. White rust resistance was completely abolished by eds1-1 but was not affected by either pad4-1 or NahG.

  4. Possible Involvement of MYB44-Mediated Stomatal Regulation in Systemic Resistance Induced by Penicillium simplicissimum GP17-2 in Arabidopsis

    Science.gov (United States)

    Hieno, Ayaka; Naznin, Hushna Ara; Hyakumachi, Mitsuro; Higuchi-Takeuchi, Mieko; Matsui, Minami; Yamamoto, Yoshiharu Y.

    2016-01-01

    The plant growth-promoting fungus (PGPF), Penicillium simplicissimum GP17-2 (GP17-2), induces systemic resistance against Pseudomonas syringae pv. tomato DC3000 (Pst) in Arabidopsis thaliana. The molecular mechanisms underlying induced systemic resistance (ISR) by GP17-2 were investigated in the present study. Microscopic observations revealed that stomatal reopening by Pst was restricted by elicitation with the culture filtrate (CF) from GP17-2. A gene expression analysis of MYB44, which enhances abscisic acid signaling and consequently closes stomata, revealed that the gene was activated by CF. CF-elicited myb44 mutant plants failed to restrict stomatal reopening and showed lower resistance to Pst than wild-type plants. These results indicate that stomatal resistance by GP17-2 is mediated by the gene activation of MYB44. We herein revealed that the MYB44-mediated prevention of penetration through the stomata is one of the components responsible for GP17-2-elicited ISR. PMID:27301421

  5. Possible Involvement of MYB44-Mediated Stomatal Regulation in Systemic Resistance Induced by Penicillium simplicissimum GP17-2 in Arabidopsis.

    Science.gov (United States)

    Hieno, Ayaka; Naznin, Hushna Ara; Hyakumachi, Mitsuro; Higuchi-Takeuchi, Mieko; Matsui, Minami; Yamamoto, Yoshiharu Y

    2016-06-25

    The plant growth-promoting fungus (PGPF), Penicillium simplicissimum GP17-2 (GP17-2), induces systemic resistance against Pseudomonas syringae pv. tomato DC3000 (Pst) in Arabidopsis thaliana. The molecular mechanisms underlying induced systemic resistance (ISR) by GP17-2 were investigated in the present study. Microscopic observations revealed that stomatal reopening by Pst was restricted by elicitation with the culture filtrate (CF) from GP17-2. A gene expression analysis of MYB44, which enhances abscisic acid signaling and consequently closes stomata, revealed that the gene was activated by CF. CF-elicited myb44 mutant plants failed to restrict stomatal reopening and showed lower resistance to Pst than wild-type plants. These results indicate that stomatal resistance by GP17-2 is mediated by the gene activation of MYB44. We herein revealed that the MYB44-mediated prevention of penetration through the stomata is one of the components responsible for GP17-2-elicited ISR.

  6. Dominant negative RPW8.2 fusion proteins reveal the importance of haustorium-oriented protein trafficking for resistance against powdery mildew in Arabidopsis.

    Science.gov (United States)

    Zhang, Qiong; Berkey, Robert; Pan, Zhiyong; Wang, Wenming; Zhang, Yi; Ma, Xianfeng; King, Harlan; Xiao, Shunyuan

    2015-01-01

    Powdery mildew fungi form feeding structures called haustoria inside epidermal cells of host plants to extract photosynthates for their epiphytic growth and reproduction. The haustorium is encased by an interfacial membrane termed the extrahaustorial membrane (EHM). The atypical resistance protein RPW8.2 from Arabidopsis is specifically targeted to the EHM where RPW8.2 activates haustorium-targeted (thus broad-spectrum) resistance against powdery mildew fungi. EHM-specific localization of RPW8.2 suggests the existence of an EHM-oriented protein/membrane trafficking pathway during EHM biogenesis. However, the importance of this specific trafficking pathway for host defense has not been evaluated via a genetic approach without affecting other trafficking pathways. Here, we report that expression of EHM-oriented, nonfunctional RPW8.2 chimeric proteins exerts dominant negative effect over functional RPW8.2 and potentially over other EHM-localized defense proteins, thereby compromising both RPW8.2-mediated and basal resistance to powdery mildew. Thus, our results highlight the importance of the EHM-oriented protein/membrane trafficking pathway for host resistance against haustorium-forming pathogens such as powdery mildew fungi.

  7. Insight into herbicide resistance of W574L mutant Arabidopsis thaliana acetohydroxyacid synthase:molecular dynamics simulations and binding free energy calculations

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Acetohydroxyacid synthase(AHAS) is the target enzyme of several classes of herbicides,such as sulfonylureas and imidazolinones.Now many mutant AHASs with herbicide resistance have emerged along with extensive use of herbicides,therefore it is imperative to understand the detailed interaction mechanism and resistance mechanism so as to develop new potent inhibitors for wild-type or resistant AHAS.With the aid of available crystal structures of the Arabidopsis thaliana(At) AHAS-inhibitor complex,molecular dynamics(MD) simulations were used to investigate the interaction and resistance mechanism directly and dynamically at the atomic level.Nanosecond-level MD simulations were performed on six systems consisting of wild-type or W574L mutant AtAHAS in the complex with three sulfonylurea inhibitors,separately,and binding free energy was calculated for each system using the MM-GBSA method.Comprehensive analyses from structural and energetic aspects confirmed the importance of residue W574,and also indicated that W574L mutation might alert the structural charactersistic of the substrate access channel and decrease the binding affinity of inhibitors,which cooperatively weaken the effective channel-blocked effect and finally result in weaker inhibitory effect of inhibitor and corresponding herbicide resistance of W574L mutant.To our knowledge,it is the first report about MD simulations study on the AHAS-related system,which will pave the way to study the interactions between herbicides and wild-type or mutant AHAS dynamically,and decipher the resistance mechanism at the atomic level for better designing new potent anti-resistance herbicides.

  8. Crystallization and preliminary X-ray diffraction analyses of the TIR domains of three TIR-NB-LRR proteins that are involved in disease resistance in Arabidopsis thaliana.

    Science.gov (United States)

    Wan, Li; Zhang, Xiaoxiao; Williams, Simon J; Ve, Thomas; Bernoux, Maud; Sohn, Kee Hoon; Jones, Jonathan D G; Dodds, Peter N; Kobe, Bostjan

    2013-11-01

    The Toll/interleukin-1 receptor (TIR) domain is a protein-protein interaction domain that is found in both animal and plant immune receptors. The N-terminal TIR domain from the nucleotide-binding (NB)-leucine-rich repeat (LRR) class of plant disease-resistance (R) proteins has been shown to play an important role in defence signalling. Recently, the crystal structure of the TIR domain from flax R protein L6 was determined and this structure, combined with functional studies, demonstrated that TIR-domain homodimerization is a requirement for function of the R protein L6. To advance the molecular understanding of the function of TIR domains in R-protein signalling, the protein expression, purification, crystallization and X-ray diffraction analyses of the TIR domains of the Arabidopsis thaliana R proteins RPS4 (resistance to Pseudomonas syringae 4) and RRS1 (resistance to Ralstonia solanacearum 1) and the resistance-like protein SNC1 (suppressor of npr1-1, constitutive 1) are reported here. RPS4 and RRS1 function cooperatively as a dual resistance-protein system that prevents infection by three distinct pathogens. SNC1 is implicated in resistance pathways in Arabidopsis and is believed to be involved in transcriptional regulation through its interaction with the transcriptional corepressor TPR1 (Topless-related 1). The TIR domains of all three proteins have successfully been expressed and purified as soluble proteins in Escherichia coli. Plate-like crystals of the RPS4 TIR domain were obtained using PEG 3350 as a precipitant; they diffracted X-rays to 2.05 Å resolution, had the symmetry of space group P1 and analysis of the Matthews coefficient suggested that there were four molecules per asymmetric unit. Tetragonal crystals of the RRS1 TIR domain were obtained using ammonium sulfate as a precipitant; they diffracted X-rays to 1.75 Å resolution, had the symmetry of space group P4(1)2(1)2 or P4(3)2(1)2 and were most likely to contain one molecule per asymmetric

  9. A functional EDS1 ortholog is differentially regulated in powdery mildew resistant and susceptible grapevines and complements an Arabidopsis eds1 mutant.

    Science.gov (United States)

    Gao, Fei; Shu, Xiaomei; Ali, Mohammad Babar; Howard, Susanne; Li, Nan; Winterhagen, Patrick; Qiu, Wenping; Gassmann, Walter

    2010-04-01

    Vitis vinifera (grapevine) is the most economically important deciduous fruit crop, but cultivated grapevine varieties lack adequate innate immunity to a range of devastating diseases. To identify genetic resources for grapevine innate immunity and understand pathogen defense pathways in a woody perennial plant, we focus in this study on orthologs of the central Arabidopsis thaliana defense regulator ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1). The family of EDS1-like genes is expanded in grapevine, and members of this family were previously found to be constitutively upregulated in the resistant variety 'Norton' of the North American grapevine species Vitis aestivalis, while they were induced by Erysiphe necator, the causal agent of grapevine powdery mildew (PM), in the susceptible V. vinifera variety 'Cabernet Sauvignon'. Here, we determine the responsiveness of individual EDS1-like genes in grapevine to PM and salicylic acid, and find that EDS1-like paralogs are differentially regulated in 'Cabernet Sauvignon', while two are constitutively upregulated in 'Norton'. Sequencing of VvEDS1 and VaEDS1 cDNA and genomic clones revealed high conservation in the protein-encoding sequence and some divergence of the promoter sequence in the two grapevine varieties. Complementation of the Arabidopsis eds1-1 mutant showed that the EDS1-like gene with highest predicted amino acid sequence similarity to AtEDS1 from either grapevine varieties is a functional ortholog of AtEDS1. Together, our analyses show that differential susceptibility to PM is correlated with differences in EDS1 expression, not differences in EDS1 function, between resistant 'Norton' and susceptible 'Cabernet Sauvignon'.

  10. AtTGA4, a bZIP transcription factor, confers drought resistance by enhancing nitrate transport and assimilation in Arabidopsis thaliana.

    Science.gov (United States)

    Zhong, Li; Chen, Dandan; Min, Donghong; Li, Weiwei; Xu, Zhaoshi; Zhou, Yongbin; Li, Liancheng; Chen, Ming; Ma, Youzhi

    2015-02-13

    To cope with environmental stress caused by global climate change and excessive nitrogen application, it is important to improve water and nitrogen use efficiencies in crop plants. It has been reported that higher nitrogen uptake could alleviate the damaging impact of drought stress. However, there is scant evidence to explain how nitrogen uptake affects drought resistance. In this study we observed that bZIP transcription factor AtTGA4 (TGACG motif-binding factor 4) was induced by both drought and low nitrogen stresses, and that overexpression of AtTGA4 simultaneously improved drought resistance and reduced nitrogen starvation in Arabidopsis. Following drought stress there were higher nitrogen and proline contents in transgenic AtTGA4 plants than in wild type controls, and activity of the key enzyme nitrite reductase (NIR) involved in nitrate assimilation processes was also higher. Expressions of the high-affinity nitrate transporter genes NRT2.1 and NRT2.2 and nitrate reductase genes NIA1 and NIA2 in transgenic plants were all higher than in wild type indicating that higher levels of nitrate transport and assimilation activity contributed to enhanced drought resistance of AtTGA4 transgenic plants. Thus genetic transformation with AtTGA4 may provide a new approach to simultaneously improve crop tolerance to drought and low nitrogen stresses.

  11. WRR4, a broad-spectrum TIR-NB-LRR gene from Arabidopsis thaliana that confers white rust resistance in transgenic oilseed Brassica crops.

    Science.gov (United States)

    Borhan, Mohammad Hossein; Holub, Eric B; Kindrachuk, Colin; Omidi, Mansour; Bozorgmanesh-Frad, Ghazaleh; Rimmer, S Roger

    2010-03-01

    White blister rust caused by Albugo candida (Pers.) Kuntze is a common and often devastating disease of oilseed and vegetable brassica crops worldwide. Physiological races of the parasite have been described, including races 2, 7 and 9 from Brassica juncea, B. rapa and B. oleracea, respectively, and race 4 from Capsella bursa-pastoris (the type host). A gene named WRR4 has been characterized recently from polygenic resistance in the wild brassica relative Arabidopsis thaliana (accession Columbia) that confers broad-spectrum white rust resistance (WRR) to all four of the above Al. candida races. This gene encodes a TIR-NB-LRR (Toll-like/interleukin-1 receptor-nucleotide binding-leucine-rich repeat) protein which, as with other known functional members in this subclass of intracellular receptor-like proteins, requires the expression of the lipase-like defence regulator, enhanced disease susceptibility 1 (EDS1). Thus, we used RNA interference-mediated suppression of EDS1 in a white rust-resistant breeding line of B. napus (transformed with a construct designed from the A. thaliana EDS1 gene) to determine whether defence signalling via EDS1 is functionally intact in this oilseed brassica. The eds1-suppressed lines were fully susceptible following inoculation with either race 2 or 7 isolates of Al. candida. We then transformed white rust-susceptible cultivars of B. juncea (susceptible to race 2) and B. napus (susceptible to race 7) with the WRR4 gene from A. thaliana. The WRR4-transformed lines were resistant to the corresponding Al. candida race for each host species. The combined data indicate that WRR4 could potentially provide a novel source of white rust resistance in oilseed and vegetable brassica crops.

  12. Overexpression of Poplar PtrWRKY89 in Transgenic Arabidopsis Leads to a Reduction of Disease Resistance by Regulating Defense-Related Genes in Salicylate- and Jasmonate-Dependent Signaling.

    Directory of Open Access Journals (Sweden)

    Yuanzhong Jiang

    Full Text Available The plant hormones jasmonic acid (JA and salicylic acid (SA play key roles in plant defenses against pathogens and several WRKY transcription factors have been shown to have a role in SA/JA crosstalk. In a previous study, overexpression of the poplar WRKY gene PtrWRKY89 enhanced resistance to pathogens in transgenic poplars. In this study, the promoter of PtrWRKY89 (ProPtrWRKY89 was isolated and used to drive GUS reporter gene. High GUS activity was observed in old leaves of transgenic Arabidopsis containing ProPtrWRKY89-GUS construct and GUS expression was extremely induced by SA solution and SA+MeJA mixture but not by MeJA treatment. Subcellular localization and transactivation assays showed that PtrWRKY89 acted as a transcription activator in the nucleus. Constitutive expression of PtrWRKY89 in Arabidopsis resulted in more susceptible to Pseudomonas syringae and Botrytis cinerea compared to wild-type plants. Quantitative real-time PCR (qRT-PCR analysis confirmed that marker genes of SA and JA pathways were down-regulated in transgenic Arabidopsis after pathogen inoculations. Overall, our results indicated that PtrWRKY89 modulates a cross talk in resistance to P. syringe and B. cinerea by negatively regulating both SA and JA pathways in Arabidopsis.

  13. The Arabidopsis KH-Domain RNA-Binding Protein ESR1 Functions in Components of Jasmonate Signalling, Unlinking Growth Restraint and Resistance to Stress.

    Directory of Open Access Journals (Sweden)

    Louise F Thatcher

    Full Text Available Glutathione S-transferases (GSTs play important roles in the protection of cells against toxins and oxidative damage where one Arabidopsis member, GSTF8, has become a commonly used marker gene for early stress and defense responses. A GSTF8 promoter fragment fused to the luciferase reporter gene was used in a forward genetic screen for Arabidopsis mutants with up-regulated GSTF8 promoter activity. This identified the esr1-1 (enhanced stress response 1 mutant which also conferred increased resistance to the fungal pathogen Fusarium oxysporum. Through positional cloning, the ESR1 gene was found to encode a KH-domain containing RNA-binding protein (At5g53060. Whole transcriptome sequencing of esr1-1 identified altered expression of genes involved in responses to biotic and abiotic stimuli, hormone signaling pathways and developmental processes. In particular was an overall significant enrichment for jasmonic acid (JA mediated processes in the esr1-1 down-regulated dataset. A subset of these genes were tested for MeJA inducibility and we found the expression of some but not all were reduced in esr1-1. The esr1-1 mutant was not impaired in other aspects of JA-signalling such as JA- sensitivity or development, suggesting ESR1 functions in specific components of the JA-signaling pathway. Examination of salicylic acid (SA regulated marker genes in esr1-1 showed no increase in basal or SA induced expression suggesting repression of JA-regulated genes is not due to antagonistic SA-JA crosstalk. These results define new roles for KH-domain containing proteins with ESR1 unlinking JA-mediated growth and defense responses.

  14. Rhizobacterial volatiles and photosynthesis-related signals coordinate MYB72 expression in Arabidopsis roots during onset of induced systemic resistance and iron-deficiency responses.

    Science.gov (United States)

    Zamioudis, Christos; Korteland, Jolanda; Van Pelt, Johan A; van Hamersveld, Muriël; Dombrowski, Nina; Bai, Yang; Hanson, Johannes; Van Verk, Marcel C; Ling, Hong-Qing; Schulze-Lefert, Paul; Pieterse, Corné M J

    2015-10-01

    In Arabidopsis roots, the transcription factor MYB72 plays a dual role in the onset of rhizobacteria-induced systemic resistance (ISR) and plant survival under conditions of limited iron availability. Previously, it was shown that MYB72 coordinates the expression of a gene module that promotes synthesis and excretion of iron-mobilizing phenolic compounds in the rhizosphere, a process that is involved in both iron acquisition and ISR signaling. Here, we show that volatile organic compounds (VOCs) from ISR-inducing Pseudomonas bacteria are important elicitors of MYB72. In response to VOC treatment, MYB72 is co-expressed with the iron uptake-related genes FERRIC REDUCTION OXIDASE 2 (FRO2) and IRON-REGULATED TRANSPORTER 1 (IRT1) in a manner that is dependent on FER-LIKE IRON DEFICIENCY TRANSCRIPTION FACTOR (FIT), indicating that MYB72 is an intrinsic part of the plant's iron-acquisition response that is typically activated upon iron starvation. However, VOC-induced MYB72 expression is activated independently of iron availability in the root vicinity. Moreover, rhizobacterial VOC-mediated induction of MYB72 requires photosynthesis-related signals, while iron deficiency in the rhizosphere activates MYB72 in the absence of shoot-derived signals. Together, these results show that the ISR- and iron acquisition-related transcription factor MYB72 in Arabidopsis roots is activated by rhizobacterial volatiles and photosynthesis-related signals, and enhances the iron-acquisition capacity of roots independently of the iron availability in the rhizosphere. This work highlights the role of MYB72 in plant processes by which root microbiota simultaneously stimulate systemic immunity and activate the iron-uptake machinery in their host plants.

  15. Enhanced Botrytis cinerea resistance of Arabidopsis plants grown in compost may be explained by increased expression of defense-related genes, as revealed by microarray analysis.

    Science.gov (United States)

    Segarra, Guillem; Santpere, Gabriel; Elena, Georgina; Trillas, Isabel

    2013-01-01

    Composts are the products obtained after the aerobic degradation of different types of organic matter waste and can be used as substrates or substrate/soil amendments for plant cultivation. There is a small but increasing number of reports that suggest that foliar diseases may be reduced when using compost, rather than standard substrates, as growing medium. The purpose of this study was to examine the gene expression alteration produced by the compost to gain knowledge of the mechanisms involved in compost-induced systemic resistance. A compost from olive marc and olive tree leaves was able to induce resistance against Botrytis cinerea in Arabidopsis, unlike the standard substrate, perlite. Microarray analyses revealed that 178 genes were differently expressed, with a fold change cut-off of 1, of which 155 were up-regulated and 23 were down-regulated in compost-grown, as against perlite-grown plants. A functional enrichment study of up-regulated genes revealed that 38 Gene Ontology terms were significantly enriched. Response to stress, biotic stimulus, other organism, bacterium, fungus, chemical and abiotic stimulus, SA and ABA stimulus, oxidative stress, water, temperature and cold were significantly enriched, as were immune and defense responses, systemic acquired resistance, secondary metabolic process and oxireductase activity. Interestingly, PR1 expression, which was equally enhanced by growing the plants in compost and by B. cinerea inoculation, was further boosted in compost-grown pathogen-inoculated plants. Compost triggered a plant response that shares similarities with both systemic acquired resistance and ABA-dependent/independent abiotic stress responses.

  16. The Arabidopsis thaliana lectin receptor kinase LecRK-I.9 is required for full resistance to Pseudomonas syringae and affects jasmonate signalling.

    Science.gov (United States)

    Balagué, Claudine; Gouget, Anne; Bouchez, Olivier; Souriac, Camille; Haget, Nathalie; Boutet-Mercey, Stéphanie; Govers, Francine; Roby, Dominique; Canut, Hervé

    2016-07-11

    On microbial attack, plants can detect invaders and activate plant innate immunity. For the detection of pathogen molecules or cell wall damage, plants employ receptors that trigger the activation of defence responses. Cell surface proteins that belong to large families of lectin receptor kinases are candidates to function as immune receptors. Here, the function of LecRK-I.9 (At5g60300), a legume-type lectin receptor kinase involved in cell wall-plasma membrane contacts and in extracellular ATP (eATP) perception, was studied through biochemical, gene expression and reverse genetics approaches. In Arabidopsis thaliana, LecRK-I.9 expression is rapidly, highly and locally induced on inoculation with avirulent strains of Pseudomonas syringae pv. tomato (Pst). Two allelic lecrk-I.9 knock-out mutants showed decreased resistance to Pst. Conversely, over-expression of LecRK-I.9 led to increased resistance to Pst. The analysis of defence gene expression suggests an alteration of both the salicylic acid (SA) and jasmonic acid (JA) signalling pathways. In particular, LecRK-I.9 expression during plant-pathogen interaction was dependent on COI1 (CORONATINE INSENSITIVE 1) and JAR1 (JASMONATE RESISTANT 1) components, and JA-responsive transcription factors (TFs) showed altered levels of expression in plants over-expressing LecRK-I.9. A similar misregulation of these TFs was obtained by JA treatment. This study identified LecRK-I.9 as necessary for full resistance to Pst and demonstrated its involvement in the control of defence against pathogens through a regulation of JA signalling components. The role of LecRK-I.9 is discussed with regard to the potential molecular mechanisms linking JA signalling to cell wall damage and/or eATP perception.

  17. Role of intron-mediated enhancement on accumulation of an Arabidopsis NB-LRR class R-protein that confers resistance to Cucumber mosaic virus.

    Directory of Open Access Journals (Sweden)

    Yukiyo Sato

    Full Text Available The accumulation of RCY1 protein, which is encoded by RESISTANCE TO CMV(Y (RCY1, a CC-NB-LRR class R-gene, is tightly correlated with the strength of the resistance to a yellow strain of Cucumber mosaic virus [CMV(Y] in Arabidopsis thaliana. In order to enhance resistance to CMV by overexpression of RCY1, A. thaliana was transformed with intron-less RCY1 cDNA construct under the control of strong CaMV35S promoter. Remarkably, a relative amount of RCY1 protein accumulation in the transformants was much lower than that in plants expressing genomic RCY1 under the control of its native promoter. To identify a regulatory element of RCY1 that could cause such differential levels of RCY1 accumulation, a series of RCY1 cDNA and genomic RCY1 constructs were transiently expressed in Nicotiana benthamiana leaves by the Agrobacterium-mediated infiltration method. Comparative analysis of the level of RCY1 accumulation in the leaf tissues transiently expressing each construct indicated that the intron located in the RCY1-coding region of genomic RCY1, but not the native RCY1 genomic promoter or the 5'-and 3'-untranslated regions of RCY1, was indispensable for high level RCY1 accumulation. The increased levels of RCY1 accelerated plant disease defense reactions. Interestingly, such intron-mediated enhancement of RCY1 accumulation depended neither on the abundance of the RCY1 transcript nor on the RCY1 specific-intron sequence. Taken together, intron-mediated RCY1 expression seems to play a key role in the expression of complete resistance to CMV(Y by maintaining RCY1 accumulation at high levels.

  18. Suppression of edr2-mediated powdery mildew resistance, cell death and ethylene-induced senescence by mutations in ALD1 in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Haozhen Nie; Yingying Wu; Chunpeng Yao; Dingzhong Tang

    2011-01-01

    EDR2 is a negative regulator of the defense response and cell death in Arabidopsis. Loss-of-function of EDR2 leads to enhanced resistance to powdery mildew. To identify new components in the EDR2 signal transduction pathway, mutations that suppress edr2 resistant phenotypes were screened. Three mutants, edts5-1, edts5-2 and edts5-3 (edr (t)wo (s)uppressor 5), were identified. The EDTS5 gene was identified by map-based cloning and previously was shown to encode an aminotransferase (ALD1). Therefore we renamed these three alleles ald1-10, ald1-11 and ald1-12, respectively. Mutations in ALD1 suppressed all edr2-mediated phenotypes, including powdery mildew resistance, programmed cell death and ethylene-induced senescence. Accumulation of hydrogen peroxide in edr2 was also suppressed by ald1 mutation. The expression of defense-related genes was up-regulated in the edr2 mutant, and the up-regulation of those genes in edr2 was suppressed in the edr2/ald1 double mutant. The ald1 single mutant displayed delayed ethylene-induced senescence. In addition, ald1 mutation suppressed edr1-mediated powdery mildew resistance, but could not suppress the edr1/edr2 double-mutant phenotype. These data demonstrate that ALD1 plays important roles in edr2-mediated defense responses and senescence, and revealed a crosstalk between ethylene and salicylic acid signaling mediated by ALD1 and EDR2.

  19. Enhanced Botrytis cinerea resistance of Arabidopsis plants grown in compost may be explained by increased expression of defense-related genes, as revealed by microarray analysis.

    Directory of Open Access Journals (Sweden)

    Guillem Segarra

    Full Text Available Composts are the products obtained after the aerobic degradation of different types of organic matter waste and can be used as substrates or substrate/soil amendments for plant cultivation. There is a small but increasing number of reports that suggest that foliar diseases may be reduced when using compost, rather than standard substrates, as growing medium. The purpose of this study was to examine the gene expression alteration produced by the compost to gain knowledge of the mechanisms involved in compost-induced systemic resistance. A compost from olive marc and olive tree leaves was able to induce resistance against Botrytis cinerea in Arabidopsis, unlike the standard substrate, perlite. Microarray analyses revealed that 178 genes were differently expressed, with a fold change cut-off of 1, of which 155 were up-regulated and 23 were down-regulated in compost-grown, as against perlite-grown plants. A functional enrichment study of up-regulated genes revealed that 38 Gene Ontology terms were significantly enriched. Response to stress, biotic stimulus, other organism, bacterium, fungus, chemical and abiotic stimulus, SA and ABA stimulus, oxidative stress, water, temperature and cold were significantly enriched, as were immune and defense responses, systemic acquired resistance, secondary metabolic process and oxireductase activity. Interestingly, PR1 expression, which was equally enhanced by growing the plants in compost and by B. cinerea inoculation, was further boosted in compost-grown pathogen-inoculated plants. Compost triggered a plant response that shares similarities with both systemic acquired resistance and ABA-dependent/independent abiotic stress responses.

  20. The disease resistance signaling components EDS1 and PAD4 are essential regulators of the cell death pathway controlled by LSD1 in Arabidopsis.

    Science.gov (United States)

    Rustérucci, C; Aviv, D H; Holt, B F; Dangl, J L; Parker, J E

    2001-10-01

    Specific recognition of pathogens is mediated by plant disease resistance (R) genes and translated into a successful defense response. The extent of associated hypersensitive cell death varies from none to an area encompassing cells surrounding an infection site, depending on the R gene activated. We constructed double mutants in Arabidopsis between positive regulators of R function and a negative regulator of cell death, LSD1, to address whether genes required for normal R function also regulate the runaway cell death observed in lsd1 mutants. We report here that EDS1 and PAD4, two signaling genes that mediate some but not all R responses, also are required for runaway cell death in the lsd1 mutant. Importantly, this novel function of EDS1 and PAD4 is operative when runaway cell death in lsd1 is initiated through an R gene that does not require EDS1 or PAD4 for disease resistance. NDR1, another component of R signaling, also contributes to the control of plant cell death. The roles of EDS1 and PAD4 in regulating lsd1 runaway cell death are related to the interpretation of reactive oxygen intermediate-derived signals at infection sites. We further demonstrate that the fate of superoxide at infection sites is different from that observed at the leading margins of runaway cell death lesions in lsd1 mutants.

  1. Leucine zipper motif in RRS1 is crucial for the regulation of Arabidopsis dual resistance protein complex RPS4/RRS1.

    Science.gov (United States)

    Narusaka, Mari; Toyoda, Kazuhiro; Shiraishi, Tomonori; Iuchi, Satoshi; Takano, Yoshitaka; Shirasu, Ken; Narusaka, Yoshihiro

    2016-01-11

    Arabidopsis thaliana leucine-rich repeat-containing (NLR) proteins RPS4 and RRS1, known as dual resistance proteins, confer resistance to multiple pathogen isolates, such as the bacterial pathogens Pseudomonas syringae and Ralstonia solanacearum and the fungal pathogen Colletotrichum higginsianum. RPS4 is a typical Toll/interleukin 1 Receptor (TIR)-type NLR, whereas RRS1 is an atypical TIR-NLR that contains a leucine zipper (LZ) motif and a C-terminal WRKY domain. RPS4 and RRS1 are localised near each other in a head-to-head orientation. In this study, direct mutagenesis of the C-terminal LZ motif in RRS1 caused an autoimmune response and stunting in the mutant. Co-immunoprecipitation analysis indicated that full-length RPS4 and RRS1 are physically associated with one another. Furthermore, virus-induced gene silencing experiments showed that hypersensitive-like cell death triggered by RPS4/LZ motif-mutated RRS1 depends on EDS1. In conclusion, we suggest that the RRS1-LZ motif is crucial for the regulation of the RPS4/RRS1 complex.

  2. The Arabidopsis mediator complex subunit16 positively regulates salicylate-mediated systemic acquired resistance and jasmonate/ethylene-induced defense pathways.

    Science.gov (United States)

    Zhang, Xudong; Wang, Chenggang; Zhang, Yanping; Sun, Yijun; Mou, Zhonglin

    2012-10-01

    Systemic acquired resistance (SAR) is a long-lasting plant immunity against a broad spectrum of pathogens. Biological induction of SAR requires the signal molecule salicylic acid (SA) and involves profound transcriptional changes that are largely controlled by the transcription coactivator nonexpressor of pathogenesis-related genes1 (NPR1). However, it is unclear how SAR signals are transduced from the NPR1 signaling node to the general transcription machinery. Here, we report that the Arabidopsis thaliana Mediator subunit16 (MED16) is an essential positive regulator of SAR. Mutations in MED16 reduced NPR1 protein levels and completely compromised biological induction of SAR. These mutations also significantly suppressed SA-induced defense responses, altered the transcriptional changes induced by the avirulent bacterial pathogen Pseudomonas syringae pv tomato (Pst) DC3000/avrRpt2, and rendered plants susceptible to both Pst DC3000/avrRpt2 and Pst DC3000. In addition, mutations in MED16 blocked the induction of several jasmonic acid (JA)/ethylene (ET)-responsive genes and compromised resistance to the necrotrophic fungal pathogens Botrytis cinerea and Alternaria brassicicola. The Mediator complex acts as a bridge between specific transcriptional activators and the RNA polymerase II transcription machinery; therefore, our data suggest that MED16 may be a signaling component in the gap between the NPR1 signaling node and the general transcription machinery and may relay signals from both the SA and the JA/ET pathways.

  3. β-Glucosidase BGLU42 is a MYB72-dependent key regulator of rhizobacteria-induced systemic resistance and modulates iron deficiency responses in Arabidopsis roots.

    Science.gov (United States)

    Zamioudis, Christos; Hanson, Johannes; Pieterse, Corné M J

    2014-10-01

    Selected soil-borne rhizobacteria can trigger an induced systemic resistance (ISR) that is effective against a broad spectrum of pathogens. In Arabidopsis thaliana, the root-specific transcription factor MYB72 is required for the onset of ISR, but is also associated with plant survival under conditions of iron deficiency. Here, we investigated the role of MYB72 in both processes. To identify MYB72 target genes, we analyzed the root transcriptomes of wild-type Col-0, mutant myb72 and complemented 35S:FLAG-MYB72/myb72 plants in response to ISR-inducing Pseudomonas fluorescens WCS417. Five WCS417-inducible genes were misregulated in myb72 and complemented in 35S:FLAG-MYB72/myb72. Amongst these, we uncovered β-glucosidase BGLU42 as a novel component of the ISR signaling pathway. Overexpression of BGLU42 resulted in constitutive disease resistance, whereas the bglu42 mutant was defective in ISR. Furthermore, we found 195 genes to be constitutively upregulated in MYB72-overexpressing roots in the absence of WCS417. Many of these encode enzymes involved in the production of iron-mobilizing phenolic metabolites under conditions of iron deficiency. We provide evidence that BGLU42 is required for their release into the rhizosphere. Together, this work highlights a thus far unidentified link between the ability of beneficial rhizobacteria to stimulate systemic immunity and mechanisms induced by iron deficiency in host plants.

  4. Comparative sequence analysis of Solanum and Arabidopsis in a hot spot for pathogen resistance on potato chromosome V reveals a patchwork of conserved and rapidly evolving genome segments

    Directory of Open Access Journals (Sweden)

    Bruggmann Rémy

    2007-05-01

    Full Text Available Abstract Background Quantitative phenotypic variation of agronomic characters in crop plants is controlled by environmental and genetic factors (quantitative trait loci = QTL. To understand the molecular basis of such QTL, the identification of the underlying genes is of primary interest and DNA sequence analysis of the genomic regions harboring QTL is a prerequisite for that. QTL mapping in potato (Solanum tuberosum has identified a region on chromosome V tagged by DNA markers GP21 and GP179, which contains a number of important QTL, among others QTL for resistance to late blight caused by the oomycete Phytophthora infestans and to root cyst nematodes. Results To obtain genomic sequence for the targeted region on chromosome V, two local BAC (bacterial artificial chromosome contigs were constructed and sequenced, which corresponded to parts of the homologous chromosomes of the diploid, heterozygous genotype P6/210. Two contiguous sequences of 417,445 and 202,781 base pairs were assembled and annotated. Gene-by-gene co-linearity was disrupted by non-allelic insertions of retrotransposon elements, stretches of diverged intergenic sequences, differences in gene content and gene order. The latter was caused by inversion of a 70 kbp genomic fragment. These features were also found in comparison to orthologous sequence contigs from three homeologous chromosomes of Solanum demissum, a wild tuber bearing species. Functional annotation of the sequence identified 48 putative open reading frames (ORF in one contig and 22 in the other, with an average of one ORF every 9 kbp. Ten ORFs were classified as resistance-gene-like, 11 as F-box-containing genes, 13 as transposable elements and three as transcription factors. Comparing potato to Arabidopsis thaliana annotated proteins revealed five micro-syntenic blocks of three to seven ORFs with A. thaliana chromosomes 1, 3 and 5. Conclusion Comparative sequence analysis revealed highly conserved collinear regions

  5. Reference: 724 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available is required in the roots during early signaling steps of rhizobacteria-mediated ...ISR. MYB72 is required in early signaling steps of rhizobacteria-induced systemic resistance in Arabidopsis.

  6. Systemic resistance in Arabidopsis induced by biocontrol bacteria is independent of salicylic acid accumulation and pathogenesis-related gene expression

    NARCIS (Netherlands)

    Pieterse, C.M.J.; Wees, A.C.M. van; Hoffland, E.; Pelt, J.A. van; Loon, L.C. van

    1996-01-01

    Systemic acquired resistance is a pathogen-inducible defense mechanism in plants. The resistant state is dependent on endogenous accumulation of salicylic acid (SA) and is characterized by the activation of genes encoding pathogenesis-related (PR) proteins. Recently, selected nonpathogenic, root-col

  7. Transformation of tobacco and Arabidopsis plants with Stellaria media genes encoding novel hevein-like peptides increases their resistance to fungal pathogens.

    Science.gov (United States)

    R Shukurov, Rahim; D Voblikova, Vera; Nikonorova, Alexandra K; Komakhin, Roman A; V Komakhina, Vera; A Egorov, Tsezi; V Grishin, Eugene; V Babakov, Alexey

    2012-04-01

    Two novel antifungal hevein-like peptides, SmAMP1.1a and SmAMP2.2a, were previously isolated from seeds of Stellaria media. It has been established that these peptides accumulate in this weed as a result of proteolysis of two propeptides, pro-SmAMP1 and pro-SmAMP2. The primary structure of these propeptides is unique; in addition to having a signal peptide and negatively charged C-terminus, each of these structures consists of two hevein-like peptides of different length separated by a space rather than a single peptide. In this work, we demonstrated that the expression of the pro-SmAMP1 and pro-SmAMP2 genes was tissue-specific and increased substantially under exposure to fungal infection. To elucidate whether S. media has any advantages in defending against phytopathogens due to its unusual structure of pro-SmAMP1 and pro-SmAMP2, on the basis of the pro-SmAMP1 gene, we created three genetic constructs. Arabidopsis and tobacco plants were subsequently transformed with these constructs. Transgenic plants bearing the full-length pro-SmAMP1 gene exhibited the best resistance to the phytopathogens Bipolaris sorokiniana and Thielaviopsis basicola. The resistance of S. media plants to phytopathogenic fungi was likely due to the fungal-inducible expression of pro-SmAMP1 and pro-SmAMP2 genes, and due to the specific features of the primary structure of the corresponding propeptides. As a result of the processing of these propeptides, two different antimicrobial peptides were released simultaneously. Based on our results, we conclude that the genes for antimicrobial peptides from S. media may be promising genetic tools for the improvement of plant resistance to fungal diseases.

  8. Separating the roles of acropetal and basipetal auxin transport on gravitropism with mutations in two Arabidopsis multidrug resistance-like ABC transporter genes.

    Science.gov (United States)

    Lewis, Daniel R; Miller, Nathan D; Splitt, Bessie L; Wu, Guosheng; Spalding, Edgar P

    2007-06-01

    Two Arabidopsis thaliana ABC transporter genes linked to auxin transport by various previous results were studied in a reverse-genetic fashion. Mutations in Multidrug Resistance-Like1 (MDR1) reduced acropetal auxin transport in roots by 80% without affecting basipetal transport. Conversely, mutations in MDR4 blocked 50% of basipetal transport without affecting acropetal transport. Developmental and auxin distribution phenotypes associated with these altered auxin flows were studied with a high-resolution morphometric system and confocal microscopy, respectively. Vertically grown mdr1 roots produced positive and negative curvatures threefold greater than the wild type, possibly due to abnormal auxin distribution observed in the elongation zone. However, upon 90 degrees reorientation, mdr1 gravitropism was inseparable from the wild type. Thus, acropetal auxin transport maintains straight growth but contributes surprisingly little to gravitropism. Conversely, vertically maintained mdr4 roots grew as straight as the wild type, but their gravitropism was enhanced. Upon reorientation, curvature in this mutant developed faster, was distributed more basally, and produced a greater total angle than the wild type. An amplified auxin asymmetry may explain the mdr4 hypertropism. Double mutant analysis indicated that the two auxin transport streams are more independent than interdependent. The hypothesis that flavanols regulate MDR-dependent auxin transport was supported by the epistatic relationship of mdr4 to the tt4 phenylpropanoid pathway mutation.

  9. Arabidopsis thaliana DM2h (R8) within the Landsberg RPP1-like Resistance Locus Underlies Three Different Cases of EDS1-Conditioned Autoimmunity.

    Science.gov (United States)

    Stuttmann, Johannes; Peine, Nora; Garcia, Ana V; Wagner, Christine; Choudhury, Sayan R; Wang, Yiming; James, Geo Velikkakam; Griebel, Thomas; Alcázar, Ruben; Tsuda, Kenichi; Schneeberger, Korbinian; Parker, Jane E

    2016-04-01

    Plants have a large panel of nucleotide-binding/leucine rich repeat (NLR) immune receptors which monitor host interference by diverse pathogen molecules (effectors) and trigger disease resistance pathways. NLR receptor systems are necessarily under tight control to mitigate the trade-off between induced defenses and growth. Hence, mis-regulated NLRs often cause autoimmunity associated with stunting and, in severe cases, necrosis. Nucleocytoplasmic ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1) is indispensable for effector-triggered and autoimmune responses governed by a family of Toll-Interleukin1-Receptor-related NLR receptors (TNLs). EDS1 operates coincidently or immediately downstream of TNL activation to transcriptionally reprogram cells for defense. We show here that low levels of nuclear-enforced EDS1 are sufficient for pathogen resistance in Arabidopsis thaliana, without causing negative effects. Plants expressing higher nuclear EDS1 amounts have the genetic, phenotypic and transcriptional hallmarks of TNL autoimmunity. In a screen for genetic suppressors of nuclear EDS1 autoimmunity, we map multiple, independent mutations to one gene, DM2h, lying within the polymorphic DANGEROUS MIX2 cluster of TNL RPP1-like genes from A. thaliana accession Landsberg erecta (Ler). The DM2 locus is a known hotspot for deleterious epistatic interactions leading to immune-related incompatibilities between A. thaliana natural accessions. We find that DM2hLer underlies two further genetic incompatibilities involving the RPP1-likeLer locus and EDS1. We conclude that the DM2hLer TNL protein and nuclear EDS1 cooperate, directly or indirectly, to drive cells into an immune response at the expense of growth. A further conclusion is that regulating the available EDS1 nuclear pool is fundamental for maintaining homeostatic control of TNL immune pathways.

  10. Arabidopsis thaliana DM2h (R8 within the Landsberg RPP1-like Resistance Locus Underlies Three Different Cases of EDS1-Conditioned Autoimmunity.

    Directory of Open Access Journals (Sweden)

    Johannes Stuttmann

    2016-04-01

    Full Text Available Plants have a large panel of nucleotide-binding/leucine rich repeat (NLR immune receptors which monitor host interference by diverse pathogen molecules (effectors and trigger disease resistance pathways. NLR receptor systems are necessarily under tight control to mitigate the trade-off between induced defenses and growth. Hence, mis-regulated NLRs often cause autoimmunity associated with stunting and, in severe cases, necrosis. Nucleocytoplasmic ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1 is indispensable for effector-triggered and autoimmune responses governed by a family of Toll-Interleukin1-Receptor-related NLR receptors (TNLs. EDS1 operates coincidently or immediately downstream of TNL activation to transcriptionally reprogram cells for defense. We show here that low levels of nuclear-enforced EDS1 are sufficient for pathogen resistance in Arabidopsis thaliana, without causing negative effects. Plants expressing higher nuclear EDS1 amounts have the genetic, phenotypic and transcriptional hallmarks of TNL autoimmunity. In a screen for genetic suppressors of nuclear EDS1 autoimmunity, we map multiple, independent mutations to one gene, DM2h, lying within the polymorphic DANGEROUS MIX2 cluster of TNL RPP1-like genes from A. thaliana accession Landsberg erecta (Ler. The DM2 locus is a known hotspot for deleterious epistatic interactions leading to immune-related incompatibilities between A. thaliana natural accessions. We find that DM2hLer underlies two further genetic incompatibilities involving the RPP1-likeLer locus and EDS1. We conclude that the DM2hLer TNL protein and nuclear EDS1 cooperate, directly or indirectly, to drive cells into an immune response at the expense of growth. A further conclusion is that regulating the available EDS1 nuclear pool is fundamental for maintaining homeostatic control of TNL immune pathways.

  11. Cerato-platanin induces resistance in Arabidopsis leaves through stomatal perception, overexpression of salicylic acid- and ethylene-signalling genes and camalexin biosynthesis.

    Science.gov (United States)

    Baccelli, Ivan; Lombardi, Lara; Luti, Simone; Bernardi, Rodolfo; Picciarelli, Piero; Scala, Aniello; Pazzagli, Luigia

    2014-01-01

    Microbe-associated molecular patterns (MAMPs) lead to the activation of the first line of plant defence. Few fungal molecules are universally qualified as MAMPs, and proteins belonging to the cerato-platanin protein (CPP) family seem to possess these features. Cerato-platanin (CP) is the name-giving protein of the CPP family and is produced by Ceratocystis platani, the causal agent of the canker stain disease of plane trees (Platanus spp.). On plane tree leaves, the biological activity of CP has been widely studied. Once applied on the leaf surface, CP acts as an elicitor of defence responses. The molecular mechanism by which CP elicits leaves is still unknown, and the protective effect of CP against virulent pathogens has not been clearly demonstrated. In the present study, we tried to address these questions in the model plant Arabidopsis thaliana. Our results suggest that stomata rapidly sense CP since they responded to the treatment with ROS signalling and stomatal closure, and that CP triggers salicylic acid (SA)- and ethylene (ET)-signalling pathways, but not the jasmonic acid (JA)-signalling pathway, as revealed by the expression pattern of 20 marker genes. Among these, EDS1, PAD4, NPR1, GRX480, WRKY70, ACS6, ERF1a/b, COI1, MYC2, PDF1.2a and the pathogenesis-related (PR) genes 1-5. CP rapidly induced MAPK phosphorylation and induced the biosynthesis of camalexin within 12 hours following treatment. The induction of localised resistance was shown by a reduced susceptibility of the leaves to the infection with Botrytis cinerea and Pseudomonas syringae pv. tomato. These results contribute to elucidate the key steps of the signalling process underlying the resistance induction in plants by CP and point out the central role played by the stomata in this process.

  12. PAPP2C Interacts with the Atypical Disease Resistance Protein RPW8.2 and Negatively Regulates Salicylic Acid-Dependent Defense Responses in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Wen-Ming Wang; Xian-Feng Ma; Yi Zhang; Ming-Cheng Luo; Guo-Liang Wang; Maria Bellizzi; Xing-Yao Xiong; Shun-Yuan Xiao

    2012-01-01

    Many fungal and oomycete pathogens differentiate a feeding structure named the haustorium to extract nutrition from the plant epidermal cell.The atypical resistance (R) protein RPW8.2 activates salicylic acid (SA)-dependent,haustorium-targeted defenses against Golovinomyces spp.,the causal agents of powdery mildew diseases on multiple plant species.How RPW8.2 activates defense remains uncharacterized.Here,we report that RPW8.2 interacts with the phytochrome-associated protein phosphatase type 2C (PAPP2C) in yeast and in planta as evidenced by coimmunoprecipitation and bimolecular fluorescence complementation assays.Down-regulation of PAPP2C by RNA interference (RNAi) in Col-0 plants lacking RPW8.2 leads to leaf spontaneous cell death and enhanced disease resistance to powdery mildew via the SA-dependent signaling pathway.Moreover,down-regulation of PAPP2C by RNAi in the RPW8.2 background results in strong HR-like cell death,which correlates with elevated RPW8.2 expression.We further demonstrate that hemagglutinin (HA)-tagged PAPP2C prepared from tobacco leaf cells transiently transformed with HA-PAPP2C possesses phosphatase activity.In addition,silencing a rice gene (Os04g0452000) homologous to PAPP2C also results in spontaneous cell death in rice.Combined,our results suggest that RPW8.2 is functionally connected with PAPP2C and that PAPP2C negatively regulates SA-dependent basal defense against powdery mildew in Arabidopsis.

  13. IAA-Ala Resistant3, an evolutionarily conserved target of miR167, mediates Arabidopsis root architecture changes during high osmotic stress

    KAUST Repository

    Kinoshita, Natsuko

    2012-09-01

    The functions of microRNAs and their target mRNAs in Arabidopsis thaliana development have been widely documented; however, roles of stress-responsive microRNAs and their targets are not as well understood. Using small RNA deep sequencing and ATH1 microarrays to profile mRNAs, we identified IAA-Ala Resistant3 (IAR3) as a new target of miR167a. As expected, IAR3 mRNA was cleaved at the miR167a complementary site and under high osmotic stress miR167a levels decreased, whereas IAR3 mRNA levels increased. IAR3 hydrolyzes an inactive form of auxin (indole-3-acetic acid [IAA]-alanine) and releases bioactive auxin (IAA), a central phytohormone for root development. In contrast with the wild type, iar3 mutants accumulated reduced IAA levels and did not display high osmotic stress-induced root architecture changes. Transgenic plants expressing a cleavage-resistant form of IAR3 mRNA accumulated high levels of IAR3 mRNAs and showed increased lateral root development compared with transgenic plants expressing wild-type IAR3. Expression of an inducible noncoding RNA to sequester miR167a by target mimicry led to an increase in IAR3 mRNA levels, further confirming the inverse relationship between the two partners. Sequence comparison revealed the miR167 target site on IAR3 mRNA is conserved in evolutionarily distant plant species. Finally, we showed that IAR3 is required for drought tolerance. © 2012 American Society of Plant Biologists. All rights reserved.

  14. Vacuolar H(+)-Pyrophosphatase AVP1 is Involved in Amine Fungicide Tolerance in Arabidopsis thaliana and Provides Tridemorph Resistance in Yeast.

    Science.gov (United States)

    Hernández, Agustín; Herrera-Palau, Rosana; Madroñal, Juan M; Albi, Tomás; López-Lluch, Guillermo; Perez-Castiñeira, José R; Navas, Plácido; Valverde, Federico; Serrano, Aurelio

    2016-01-01

    Amine fungicides are widely used as crop protectants. Their success is believed to be related to their ability to inhibit postlanosterol sterol biosynthesis in fungi, in particular sterol-Δ(8),Δ(7)-isomerases and sterol-Δ(14)-reductases, with a concomitant accumulation of toxic abnormal sterols. However, their actual cellular effects and mechanisms of death induction are still poorly understood. Paradoxically, plants exhibit a natural resistance to amine fungicides although they have similar enzymes in postcicloartenol sterol biosynthesis that are also susceptible to fungicide inhibition. A major difference in vacuolar ion homeostasis between plants and fungi is the presence of a dual set of primary proton pumps in the former (V-ATPase and H(+)-pyrophosphatase), but only the V-ATPase in the latter. Abnormal sterols affect the proton-pumping capacity of V-ATPases in fungi and this has been proposed as a major determinant in fungicide action. Using Saccharomyces cerevisiae as a model fungus, we provide evidence that amine fungicide treatment induced cell death by apoptosis. Cell death was concomitant with impaired H(+)-pumping capacity in vacuole vesicles and dependent on vacuolar proteases. Also, the heterologous expression of the Arabidopsis thaliana main H(+)-pyrophosphatase (AVP1) at the fungal vacuolar membrane reduced apoptosis levels in yeast and increased resistance to amine fungicides. Consistently, A. thaliana avp1 mutant seedlings showed increased susceptibility to this amine fungicide, particularly at the level of root development. This is in agreement with AVP1 being nearly the sole H(+)-pyrophosphatase gene expressed at the root elongation zones. All in all, the present data suggest that H(+)-pyrophosphatases are major determinants of plant tolerance to amine fungicides.

  15. Cerato-platanin induces resistance in Arabidopsis leaves through stomatal perception, overexpression of salicylic acid- and ethylene-signalling genes and camalexin biosynthesis.

    Directory of Open Access Journals (Sweden)

    Ivan Baccelli

    Full Text Available Microbe-associated molecular patterns (MAMPs lead to the activation of the first line of plant defence. Few fungal molecules are universally qualified as MAMPs, and proteins belonging to the cerato-platanin protein (CPP family seem to possess these features. Cerato-platanin (CP is the name-giving protein of the CPP family and is produced by Ceratocystis platani, the causal agent of the canker stain disease of plane trees (Platanus spp.. On plane tree leaves, the biological activity of CP has been widely studied. Once applied on the leaf surface, CP acts as an elicitor of defence responses. The molecular mechanism by which CP elicits leaves is still unknown, and the protective effect of CP against virulent pathogens has not been clearly demonstrated. In the present study, we tried to address these questions in the model plant Arabidopsis thaliana. Our results suggest that stomata rapidly sense CP since they responded to the treatment with ROS signalling and stomatal closure, and that CP triggers salicylic acid (SA- and ethylene (ET-signalling pathways, but not the jasmonic acid (JA-signalling pathway, as revealed by the expression pattern of 20 marker genes. Among these, EDS1, PAD4, NPR1, GRX480, WRKY70, ACS6, ERF1a/b, COI1, MYC2, PDF1.2a and the pathogenesis-related (PR genes 1-5. CP rapidly induced MAPK phosphorylation and induced the biosynthesis of camalexin within 12 hours following treatment. The induction of localised resistance was shown by a reduced susceptibility of the leaves to the infection with Botrytis cinerea and Pseudomonas syringae pv. tomato. These results contribute to elucidate the key steps of the signalling process underlying the resistance induction in plants by CP and point out the central role played by the stomata in this process.

  16. The salty tale of Arabidopsis.

    Science.gov (United States)

    Sanders, D

    2000-06-29

    High concentrations of sodium chloride are toxic to most plant species. New insights into the mechanisms by which plants tolerate salt have emerged from the identification of genes in Arabidopsis thaliana that play a critical part in physiological resistance to salt.

  17. Enhancement of induced disease resistance by simultaneous activation of salicylate- and jasmonate-dependent defense pathways in Arabidopsis thaliana

    NARCIS (Netherlands)

    Wees, A.C.M. van; Swart, E.A.M. de; Pelt, J.A. van; Loon, L.C. van; Pieterse, C.M.J.

    2000-01-01

    The plant-signaling molecules salicylic acid (SA) and jasmonic acid (JA) play an important role in induced disease resistance pathways. Cross-talk between SA- and JA-dependent pathways can result in inhibition of JA-mediated defense responses. We investigated possible antagonistic interactions betwe

  18. Nitric oxide responsive heavy metal-associated gene AtHMAD1 contributes to development and disease resistance in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Qari Muhammad Imran

    2016-11-01

    Full Text Available Exposure of plants to different biotic and abiotic stress condition instigates significant change in the cellular redox status; resulting in the elevation of reactive nitrogen species that play signaling role in mediating defense responses. Heavy metal associated (HMA domain containing genes are required for spatio-temporal transportation of metal ions that bind with various enzymes and co-factors within the cell. To uncover the underlying mechanisms mediated by AtHMA genes, we identified 14 Arabidopsis HMA genes that were differentially expressed in response to nitrosative stress through RNA-seq analysis. Of those 14 genes, the expression of eight HMA genes was significantly increased, whereas that of six genes was significantly reduced. We further validated the RNA-seq results through quantitative real-time PCR analysis. Gene ontology analysis revealed the involvement of these genes in biological processes such as hemostasis and transport. The majority of these nitric oxide (NO-responsive AtHMA gene products are carrier/transport proteins. AtHMAD1 (At1g51090 showed the highest fold change to S-nitrosocystein. We therefore, further investigated its role in oxidative and nitrosative mediated stress conditions and found that AtHMAD1 has antagonistic role in shoot and root growth. Characterization of AtHMAD1 through functional genomics showed that the knock out mutant athmad1 plants were resistant to virulent Pseudomonas syringae (DC3000 and showed early induction and high transcript accumulation of pathogenesis related gene. Furthermore, inoculation of athamd1 with avirulent strain of the same bacteria showed negative regulation of R-gene mediated resistance. These results were supported by hypersensitive cell death response and cell death induced electrolyte leakage. AtHMAD1 was also observed to negatively regulate systemic acquired resistance SAR as the KO mutant showed induction of SAR marker genes. Overall, these results imply that NO

  19. An Arabidopsis callose synthase

    DEFF Research Database (Denmark)

    Ostergaard, Lars; Petersen, Morten; Mattsson, Ole

    2002-01-01

    in the Arabidopsis mpk4 mutant which exhibits systemic acquired resistance (SAR), elevated beta-1,3-glucan synthase activity, and increased callose levels. In addition, AtGsl5 is a likely target of salicylic acid (SA)-dependent SAR, since AtGsl5 mRNA accumulation is induced by SA in wild-type plants, while...... expression of the nahG salicylate hydroxylase reduces AtGsl5 mRNA levels in the mpk4 mutant. These results indicate that AtGsl5 is likely involved in callose synthesis in flowering tissues and in the mpk4 mutant....

  20. Redundancy among phospholipase D isoforms in resistance triggered by recognition of the Pseudomonas syringae effector AvrRpm1 in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Oskar N Johansson

    2014-11-01

    Full Text Available Plants possess a highly sophisticated system for defense against microorganisms. So called MAMP (Microbe Associated Molecular Patterns triggered immunity (MTI prevents the majority of non-adapted pathogens from causing disease. Adapted plant pathogens use secreted effector proteins to interfere with such signaling. Recognition of microbial effectors or their activity by plant resistance (R-proteins triggers a second line of defense resulting in effector triggered immunity (ETI. The latter usually comprises the hypersensitive response (HR which includes programmed cell death at the site of infection. Phospholipase D (PLD mediated production of phosphatidic acid (PA has been linked to both MTI and ETI in plants. Inhibition of PLD activity has been shown to attenuate MTI as well as ETI. In this study, we systematically tested single and double knockouts in all 12 genes encoding PLDs in Arabidopsis thaliana for effects on ETI and MTI. No single PLD could be linked to ETI triggered by recognition of effectors secreted by the bacterium Pseudomonas syringae. However, repression of PLD dependent PA production by n-butanol strongly inhibited the HR following P. syringae effector recognition. In addition some pld mutants were more sensitive to n-butanol than wild type. Thus, the effect of mutations of PLDs could become detectable, and the corresponding genes can be proposed to be involved in the HR. Only knockout of PLDδ caused a loss of MTI-induced cell wall based defense against the non-host powdery mildew Erysiphe pisi. This is thus in stark contrast to the involvement of a multitude of PLD isoforms in the HR triggered by AvrRpm1 recognition.

  1. The bHLH transcription factor bHLH104 interacts with IAA-LEUCINE RESISTANT3 and modulates iron homeostasis in Arabidopsis.

    Science.gov (United States)

    Zhang, Jie; Liu, Bing; Li, Mengshu; Feng, Dongru; Jin, Honglei; Wang, Peng; Liu, Jun; Xiong, Feng; Wang, Jinfa; Wang, Hong-Bin

    2015-03-01

    Iron (Fe) is an indispensable micronutrient for plant growth and development. The regulation of Fe homeostasis in plants is complex and involves a number of transcription factors. Here, we demonstrate that a basic helix-loop-helix (bHLH) transcription factor, bHLH104, belonging to the IVc subgroup of bHLH family, acts as a key component positively regulating Fe deficiency responses. Knockout of bHLH104 in Arabidopsis thaliana greatly reduced tolerance to Fe deficiency, whereas overexpression of bHLH104 had the opposite effect and led to accumulation of excess Fe in soil-grown conditions. The activation of Fe deficiency-inducible genes was substantially suppressed by loss of bHLH104. Further investigation showed that bHLH104 interacted with another IVc subgroup bHLH protein, IAA-LEUCINE RESISTANT3 (ILR3), which also plays an important role in Fe homeostasis. Moreover, bHLH104 and ILR3 could bind directly to the promoters of Ib subgroup bHLH genes and POPEYE (PYE) functioning in the regulation of Fe deficiency responses. Interestingly, genetic analysis showed that loss of bHLH104 could decrease the tolerance to Fe deficiency conferred by the lesion of BRUTUS, which encodes an E3 ligase and interacts with bHLH104. Collectively, our data support that bHLH104 and ILR3 play pivotal roles in the regulation of Fe deficiency responses via targeting Ib subgroup bHLH genes and PYE expression.

  2. Long distance movement of DIR1 and investigation of the role of DIR1-like during Systemic Acquired Resistance in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Marc J Champigny

    2013-07-01

    Full Text Available DIR1 is a lipid transfer protein postulated to complex with and/or chaperone a signal(s to distant leaves during Systemic Acquired Resistance (SAR in Arabidopsis. DIR1 was detected in phloem sap-enriched petiole exudates collected from wild-type leaves induced for SAR, suggesting that DIR1 gains access to the phloem for movement from the induced leaf. Occasionally the dir1-1 mutant displayed a partially SAR-competent phenotype and a DIR1-sized band in protein gel blots was detected in dir1-1 exudates suggesting a highly similar protein, DIR1-like (At5g48490, may contribute to SAR. Recombinant protein studies demonstrated that DIR1 polyclonal antibodies recognize DIR1 and DIR1-like. Homology modeling of DIR1-like using the DIR1-phospholipid crystal structure as template, provides clues as to why DIR1-like rarely compensates for the dir1-1 SAR defect. The contribution of DIR1 and DIR1-like during SAR was examined using an Agrobacterium-mediated transient transformation-SAR assay and an estrogen-inducible DIR1-EGFP/dir1-1 line. We provide evidence that upon SAR induction, DIR1 moves down the leaf petiole to distant leaves. Our data also suggests that DIR1-like displays a reduced capacity to move to distant leaves during SAR. The existence of DIR1-like and its infrequent participation in SAR may contribute to the variable SAR responses reported by groups studying SAR mutants.

  3. Strong resistance of Arabidopsis thaliana and Raphanus sativus seeds for ionizing radiation as studied by ESR, ENDOR, ESE spectroscopy and germination measurement: Effect of long-lived and super-long-lived radicals

    Science.gov (United States)

    Kumagai, Jun; Katoh, Hiromi; Kumada, Takayuki; Tanaka, Atsushi; Tano, Shigemitsu; Miyazaki, Tetsuo

    2000-01-01

    Resistance of seeds for ionizing radiation effects on Arabidopsis thaliana and Raphanus sativus seeds were investigated by ESR, ENDOR, ESE spectroscopy and germination measurement. Two types of free radicals, such as long-lived (LL) and super-long-lived (SL) radicals, were produced by the γ-irradiation in the seeds. More than 90% of the 1 kGy-irradiated-seeds can germinate probably by decreasing the LL radicals by absorbing water. 10 kGy-irradiated-seeds cannot germinate at all probably due to the existence of significant amounts of the SL radicals even after absorbing water.

  4. Strong resistance of Arabidopsis thaliana and Raphanus sativus seeds for ionizing radiation as studied by ESR, ENDOR, ESE spectroscopy and germination measurement: Effect of long-lived and super-long-lived radicals

    Energy Technology Data Exchange (ETDEWEB)

    Kumagai, Jun E-mail: kumagai@apchem.nagoya-u.ac.jp; Katoh, Hiromi; Kumada, Takayuki; Tanaka, Atsushi; Tano, Shigemitsu; Miyazaki, Tetsuo

    2000-01-01

    Resistance of seeds for ionizing radiation effects on Arabidopsis thaliana and Raphanus sativus seeds were investigated by ESR, ENDOR, ESE spectroscopy and germination measurement. Two types of free radicals, such as long-lived (LL) and super-long-lived (SL) radicals, were produced by the {gamma}-irradiation in the seeds. More than 90% of the 1 kGy-irradiated-seeds can germinate probably by decreasing the LL radicals by absorbing water. 10 kGy-irradiated-seeds cannot germinate at all probably due to the existence of significant amounts of the SL radicals even after absorbing water. (author)

  5. Reference: 457 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available n et al. 2006 Oct. Plant J. 48(2):238-48. The Arabidopsis BAP1 gene encodes a small protein with a C2-like domain. Here...er and is associated with membranes in vivo. We identify multiple roles of BAP1 in negatively re...gulating defense responses and cell death in Arabidopsis thaliana. The loss of BAP1 function ...confers an enhanced disease resistance to virulent bacterial and oomycete pathogens. The enhanced resistance... is mediated by salicylic acid, PAD4 and a disease resistance gene SNC1. BAP1 is

  6. Ectopic expression of Arabidopsis genes encoding salicylic acid- and jasmonic acid-related proteins confers partial resistance to soybean cyst nematode (Heterodera glycines) in transgenic soybean roots

    Science.gov (United States)

    Background. Extensive studies using the model system Arabidopsis thaliana to elucidate plant defense signaling and pathway networks indicate that salicylic acid (SA) is the key hormone triggering the plant defense response against biotrophic and hemi-biotrophic pathogens, while jasmonic acid (JA) an...

  7. A mutation in negative regulator of basal resistance WRKY17 of Arabidopsis increases susceptibility to Agrobacterium-mediated genetic transformation [v1; ref status: indexed, http://f1000r.es/no

    Directory of Open Access Journals (Sweden)

    Benoît Lacroix

    2013-02-01

    Full Text Available Agrobacterium is a phytopathogenic bacterium that induces crown gall disease in many plant species by transferring and integrating a segment of its own DNA (T-DNA into its host genome. Whereas Agrobacterium usually does not trigger an extensive defense response in its host plants, it induces the expression of several defense-related genes and activates plant stress reactions. In the complex interplay between Agrobacterium and its host plant, Agrobacterium has evolved to take advantage of these plant defense pathways for its own purpose of advancement of the infection process. For example, Agrobacterium utilizes the host stress response transcriptional regulator VIP1 to facilitate nuclear import and proteasomal uncoating of its T-DNA during genetic transformation of the host cell. In Arabidopsis, the VIP1 gene expression is repressed by WRKY17, a negative regulator of basal resistance to Pseudomonas. Thus, we examined whether WRKY17 is also involved in plant susceptibility to genetic transformation by Agrobacterium. Using reverse genetics, we showed that a wrky17 mutant displays higher expression of the VIP1 gene in roots, but not in shoots. In a root infection assay, the wrky17 mutant plants were hyper-susceptible to Agrobacterium compared to wild type plants. WRKY17, therefore, may act as a positive regulator of Arabidopsis resistance to Agrobacterium. This notion is important for understanding the complex regulation of Agrobacterium-mediated genetic transformation; thus, although this paper reports a relatively small set of data that we do not plan to pursue further in our lab, we believe it might be useful for the broad community of plant pathologists and plant biotechnologists.

  8. The promoter of the nematode resistance gene Hs1pro-1 activates a nematode-responsive and feeding site-specific gene expression in sugar beet (Beta vulgaris L.) and Arabidopsis thaliana.

    Science.gov (United States)

    Thurau, Tim; Kifle, Sirak; Jung, Christian; Cai, Daguang

    2003-06-01

    The Hs1pro-1 gene confers resistance to the beet cyst nematode Heterodera schachtii in sugar beet (Beta vulgaris L.) on the basis of a gene-for-gene relationship. RNA-gel blot analysis revealed that the transcript of Hs1pro-1 was present in uninfected roots of resistant beet at low levels but increased by about fourfold one day after nematode infection. Treatments of plants with external stimuli including salicylic acid, jasmonic acid, gibberellic acid and abscisic acid as well as wounding or salt stress did not result in changes in the gene transcription, indicating de novo transcription of Hs1pro-1 upon nematode infection specifically. To study transcriptional regulation of Hs1pro-1 expression at the cellular level, a 3082 bp genomic fragment representing the Hs1pro-1 promoter, isolated from the YAC-DNA housing the Hs1pro-1 gene, was fused to the beta-glucuronidase reporter gene (1832prm1::GUS) and transformed into susceptible beet roots and Arabidopsis plants, respectively. Fluorometric and histochemical GUS assays on transgenic beet roots and Arabidopsis plants carrying the 1832prm1::GUS construct demonstrated that the Hs1pro-1 promoter is functional in both species and drives a nematode responsive and feeding site-specific GUS-expression. GUS activity was detected as early as at initiation of the nematode feeding sites and GUS staining was restricted to the nematode feeding sites. To delineate the regulatory domains of the Hs1pro-1 promoter, fusion genes with various 5' deletions of the Hs1pro-1 promoter and the GUS gene were constructed and analysed in transgenic beet roots as well. Cis elements responsible for feeding site-specific gene expression reside between -355 and +247 from the transcriptional initiation site of Hs1pro-1 whereas an enhancer region necessary for higher gene expression is located between -1199 and -705 of the promoter. The Hs1pro-1 promoter drives a nematode feeding site-specific GUS expression in both sugar beet and Arabidopsis

  9. Reference: 392 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available pment. The Arabidopsis SUPPRESSOR OF AUXIN RESISTANCE proteins are nucleoporins with an important role in ho...olyadenylated RNA within the nucleus, indicating that SAR1 and SAR3 are required for mRNA export. Our results demonstrate the importa...nt role of the plant NPC in hormone signaling and develo

  10. Expression of Caenorhabditis elegans PCS in the AtPCS1-deficient Arabidopsis thaliana cad1-3 mutant separates the metal tolerance and non-host resistance functions of phytochelatin synthases.

    Science.gov (United States)

    Kühnlenz, Tanja; Westphal, Lore; Schmidt, Holger; Scheel, Dierk; Clemens, Stephan

    2015-11-01

    Phytochelatin synthases (PCS) play key roles in plant metal tolerance. They synthesize small metal-binding peptides, phytochelatins, under conditions of metal excess. Respective mutants are strongly cadmium and arsenic hypersensitive. However, their ubiquitous presence and constitutive expression had long suggested a more general function of PCS besides metal detoxification. Indeed, phytochelatin synthase1 from Arabidopsis thaliana (AtPCS1) was later implicated in non-host resistance. The two different physiological functions may be attributable to the two distinct catalytic activities demonstrated for AtPCS1, that is the dipeptidyl transfer onto an acceptor molecule in phytochelatin synthesis, and the proteolytic deglycylation of glutathione conjugates. In order to test this hypothesis and to possibly separate the two biological roles, we expressed a phylogenetically distant PCS from Caenorhabditis elegans in an AtPCS1 mutant. We confirmed the involvement of AtPCS1 in non-host resistance by showing that plants lacking the functional gene develop a strong cell death phenotype when inoculated with the potato pathogen Phytophthora infestans. Furthermore, we found that the C. elegans gene rescues phytochelatin synthesis and cadmium tolerance, but not the defect in non-host resistance. This strongly suggests that the second enzymatic function of AtPCS1, which remains to be defined in detail, is underlying the plant immunity function.

  11. Systemic resistance induced by rhizosphere bacteria

    NARCIS (Netherlands)

    Loon, L.C. van; Bakker, P.A.H.M.; Pieterse, C.M.J.

    1998-01-01

    Nonpathogenic rhizobacteria can induce a systemic resistance in plants that is phenotypically similar to pathogen-induced systemic acquired resistance (SAR). Rhizobacteria-mediated induced systemic resistance (ISR) has been demonstrated against fungi, bacteria, and viruses in Arabidopsis, bean, carn

  12. Reference: 600 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available n M et al. 2007 Jun. Plant J. 50(5):810-24. A novel abscisic acid (ABA)-deficient mutant, aba4, was identified in a scre...en for paclobutrazol-resistant germination. Compared with wild-type, the mutant showed reduced e...by map-based cloning, and found to be a unique gene in the Arabidopsis genome. The predicted protein has fou...r putative helical transmembrane domains and shows significant similarity to pred...icted proteins from tomato, rice and cyanobacteria. Constitutive expression of the ABA4 gene in Arabidopsis

  13. Reference: 640 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available er Alois et al. 2007 Jul. Plant Cell 19(7):2213-24. Wound signaling pathways in plants are mediated by mitog...en-activated protein kinases (MAPKs) and stress hormones, such as ethylene and jasmonates. In Arabidopsis th...ed investigations; however, the involvement of specific phosphatases in wound signaling is not known. Here, ...we show that AP2C1, an Arabidopsis Ser/Thr phosphatase of type 2C, is a novel stress signal regulator that inactivates the stress-re... significantly higher amounts of jasmonate upon wounding and are more resistant to phytophagous mites (Tetra

  14. Arabidopsis hybrid speciation processes.

    Science.gov (United States)

    Schmickl, Roswitha; Koch, Marcus A

    2011-08-23

    The genus Arabidopsis provides a unique opportunity to study fundamental biological questions in plant sciences using the diploid model species Arabidopsis thaliana and Arabidopsis lyrata. However, only a few studies have focused on introgression and hybrid speciation in Arabidopsis, although polyploidy is a common phenomenon within this genus. More recently, there is growing evidence of significant gene flow between the various Arabidopsis species. So far, we know Arabidopsis suecica and Arabidopsis kamchatica as fully stabilized allopolyploid species. Both species evolved during Pleistocene glaciation and deglaciation cycles in Fennoscandinavia and the amphi-Beringian region, respectively. These hybrid studies were conducted either on a phylogeographic scale or reconstructed experimentally in the laboratory. In our study we focus at a regional and population level. Our research area is located in the foothills of the eastern Austrian Alps, where two Arabidopsis species, Arabidopsis arenosa and A. lyrata ssp. petraea, are sympatrically distributed. Our hypothesis of genetic introgression, migration, and adaptation to the changing environment during the Pleistocene has been confirmed: We observed significant, mainly unidirectional gene flow between the two species, which has given rise to the tetraploid A. lyrata. This cytotype was able to escape from the narrow ecological niche occupied by diploid A. lyrata ssp. petraea on limestone outcrops by migrating northward into siliceous areas, leaving behind a trail of genetic differentiation.

  15. TaNAC1 acts as a negative regulator of stripe rust resistance in wheat, enhances susceptibility to Pseudomonas syringae, and promotes lateral root development in transgenic Arabidopsis thaliana.

    Science.gov (United States)

    Wang, Fengtao; Lin, Ruiming; Feng, Jing; Chen, Wanquan; Qiu, Dewen; Xu, Shichang

    2015-01-01

    Plant-specific NAC transcription factors (TFs) constitute a large family and play important roles in regulating plant developmental processes and responses to environmental stresses, but only some of them have been investigated for effects on disease reaction in cereal crops. Virus-induced gene silencing (VIGS) is an effective strategy for rapid functional analysis of genes in plant tissues. In this study, TaNAC1, encoding a new member of the NAC1 subgroup, was cloned from bread wheat and characterized. It is a TF localized in the cell nucleus, and contains an activation domain in its C-terminal. TaNAC1 was strongly expressed in wheat roots and was involved in responses to infection by the obligate pathogen Puccinia striiformis f. sp. tritici and defense-related hormone treatments such as salicylic acid (SA), methyl jasmonate, and ethylene. Knockdown of TaNAC1 with barley stripe mosaic virus-induced gene silencing (BSMV-VIGS) enhanced stripe rust resistance. TaNAC1-overexpression in Arabidopsis thaliana plants gave enhanced susceptibility, attenuated systemic-acquired resistance to Pseudomonas syringae DC3000, and promoted lateral root development. Jasmonic acid-signaling pathway genes PDF1.2 and ORA59 were constitutively expressed in transgenic plants. TaNAC1 overexpression suppressed the expression levels of resistance-related genes PR1 and PR2 involved in SA signaling and AtWRKY70, which functions as a connection node between the JA- and SA-signaling pathways. Collectively, TaNAC1 is a novel NAC member of the NAC1 subgroup, negatively regulates plant disease resistance, and may modulate plant JA- and SA-signaling defense cascades.

  16. TaNAC1 acts as a negative regulator of stripe rust resistance in wheat, enhances susceptibility to Pseudomonas syringae, and promotes lateral root development in transgenic Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Fengtao eWang

    2015-02-01

    Full Text Available Plant-specific NAC transcription factors constitute a large family and play important roles in regulating plant developmental processes and responses to environmental stresses, but only some of them have been investigated for effects on disease reaction in cereal crops. Virus-induced gene silencing (VIGS is an effective strategy for rapid functional analysis of genes in plant tissues. In this study, TaNAC1, encoding a new member of the NAC1 subgroup, was cloned from bread wheat and characterized. It is a transcription factor localized in the cell nucleus, and contains an activation domain in its C-terminal. TaNAC1 was strongly expressed in wheat roots and was involved in responses to infection by the obligate pathogen Puccinia striiformis f. sp. tritici and defense-related hormone treatments such as salicylic acid, methyl jasmonate and ethylene. Knockdown of TaNAC1 with barley stripe mosaic virus-induced gene silencing (BSMV-VIGS enhanced stripe rust resistance. TaNAC1-overexpression in Arabidopsis plants gave enhanced susceptibility, attenuated systemic-acquired resistance to Pseudomonas syringae DC3000, and promoted lateral root development. Jasmonic acid-signaling pathway genes PDF1.2 and ORA59 were constitutively expressed in transgenic plants. TaNAC1 overexpression suppressed the expression levels of resistance-related genes PR1 and PR2 involved in SA signaling and AtWRKY70, which functions as a connection node between the JA- and SA-signaling pathways. Collectively, TaNAC1 is a novel NAC member of the NAC1 subgroup, negatively regulates plant disease resistance, and may modulate plant JA- and SA-signaling defense cascades.

  17. Induced Systemic Resistance against Botrytis cinerea by Bacillus cereus AR156 through a JA/ET- and NPR1-Dependent Signaling Pathway and Activates PAMP-Triggered Immunity in Arabidopsis

    Science.gov (United States)

    Nie, Pingping; Li, Xia; Wang, Shune; Guo, Jianhua; Zhao, Hongwei; Niu, Dongdong

    2017-01-01

    Induced resistance response is a potent and cost effective plant defense against pathogen attack. The effectiveness and underlying mechanisms of the suppressive ability by Bacillus cereus AR156 to Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) in Arabidopsis has been investigated previously; however, the strength of induced systemic resistance (ISR) activity against Botrytis cinerea remains unknown. Here, we show that root-drench application of AR156 significantly reduces disease incidence through activation of ISR. This protection is accompanied with multilayered ISR defense response activated via enhanced accumulation of PR1 protein expression in a timely manner, hydrogen peroxide accumulation and callose deposition, which is significantly more intense in plants with both AR156 pretreatment and B. cinerea inoculation than that in plants with pathogen inoculation only. Moreover, AR156 can trigger ISR in sid2-2 and NahG mutants, but not in jar1, ein2 and npr1 mutant plants. Our results indicate that AR156-induced ISR depends on JA/ET-signaling pathway and NPR1, but not SA. Also, AR156-treated plants are able to rapidly activate MAPK signaling and FRK1/WRKY53 gene expression, both of which are involved in pathogen associated molecular pattern (PAMP)-triggered immunity (PTI). The results indicate that AR156 can induce ISR by the JA/ET-signaling pathways in an NPR1-dependent manner and involves multiple PTI components. PMID:28293243

  18. Induced Systemic Resistance against Botrytis cinerea by Bacillus cereus AR156 through a JA/ET- and NPR1-Dependent Signaling Pathway and Activates PAMP-Triggered Immunity in Arabidopsis.

    Science.gov (United States)

    Nie, Pingping; Li, Xia; Wang, Shune; Guo, Jianhua; Zhao, Hongwei; Niu, Dongdong

    2017-01-01

    Induced resistance response is a potent and cost effective plant defense against pathogen attack. The effectiveness and underlying mechanisms of the suppressive ability by Bacillus cereus AR156 to Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) in Arabidopsis has been investigated previously; however, the strength of induced systemic resistance (ISR) activity against Botrytis cinerea remains unknown. Here, we show that root-drench application of AR156 significantly reduces disease incidence through activation of ISR. This protection is accompanied with multilayered ISR defense response activated via enhanced accumulation of PR1 protein expression in a timely manner, hydrogen peroxide accumulation and callose deposition, which is significantly more intense in plants with both AR156 pretreatment and B. cinerea inoculation than that in plants with pathogen inoculation only. Moreover, AR156 can trigger ISR in sid2-2 and NahG mutants, but not in jar1, ein2 and npr1 mutant plants. Our results indicate that AR156-induced ISR depends on JA/ET-signaling pathway and NPR1, but not SA. Also, AR156-treated plants are able to rapidly activate MAPK signaling and FRK1/WRKY53 gene expression, both of which are involved in pathogen associated molecular pattern (PAMP)-triggered immunity (PTI). The results indicate that AR156 can induce ISR by the JA/ET-signaling pathways in an NPR1-dependent manner and involves multiple PTI components.

  19. Ectopic Expression of the Wild Grape WRKY Transcription Factor VqWRKY52 in Arabidopsis thaliana Enhances Resistance to the Biotrophic Pathogen Powdery Mildew But Not to the Necrotrophic Pathogen Botrytis cinerea

    Science.gov (United States)

    Wang, Xianhang; Guo, Rongrong; Tu, Mingxing; Wang, Dejun; Guo, Chunlei; Wan, Ran; Li, Zhi; Wang, Xiping

    2017-01-01

    WRKY transcription factors are known to play important roles in plant responses to biotic stresses. We previously showed that the expression of the WRKY gene, VqWRKY52, from Chinese wild Vitis quinquangularis was strongly induced 24 h post inoculation with powdery mildew. In this study, we analyzed the expression levels of VqWRKY52 following treatment with the defense related hormones salicylic acid (SA) and methyl jasmonate, revealing that VqWRKY52 was strongly induced by SA but not JA. We characterized the VqWRKY52 gene, which encodes a WRKY III gene family member, and found that ectopic expression in Arabidopsis thaliana enhanced resistance to powdery mildew and Pseudomonas syringae pv. tomato DC3000, but increased susceptibility to Botrytis cinerea, compared with wild type (WT) plants. The transgenic A. thaliana lines displayed strong cell death induced by the biotrophic powdery mildew pathogen, the hemibiotrophic P. syringe pathogen and the necrotrophic pathogen B. cinerea. In addition, the relative expression levels of various defense-related genes were compared between the transgenic A. thaliana lines and WT plants following the infection by different pathogens. Collectively, the results indicated that VqWRKY52 plays essential roles in the SA dependent signal transduction pathway and that it can enhance the hypersensitive response cell death triggered by microbial pathogens. PMID:28197166

  20. Ectopic Expression of the Wild Grape WRKY Transcription Factor VqWRKY52 in Arabidopsis thaliana Enhances Resistance to the Biotrophic Pathogen Powdery Mildew But Not to the Necrotrophic Pathogen Botrytis cinerea.

    Science.gov (United States)

    Wang, Xianhang; Guo, Rongrong; Tu, Mingxing; Wang, Dejun; Guo, Chunlei; Wan, Ran; Li, Zhi; Wang, Xiping

    2017-01-01

    WRKY transcription factors are known to play important roles in plant responses to biotic stresses. We previously showed that the expression of the WRKY gene, VqWRKY52, from Chinese wild Vitis quinquangularis was strongly induced 24 h post inoculation with powdery mildew. In this study, we analyzed the expression levels of VqWRKY52 following treatment with the defense related hormones salicylic acid (SA) and methyl jasmonate, revealing that VqWRKY52 was strongly induced by SA but not JA. We characterized the VqWRKY52 gene, which encodes a WRKY III gene family member, and found that ectopic expression in Arabidopsis thaliana enhanced resistance to powdery mildew and Pseudomonas syringae pv. tomato DC3000, but increased susceptibility to Botrytis cinerea, compared with wild type (WT) plants. The transgenic A. thaliana lines displayed strong cell death induced by the biotrophic powdery mildew pathogen, the hemibiotrophic P. syringe pathogen and the necrotrophic pathogen B. cinerea. In addition, the relative expression levels of various defense-related genes were compared between the transgenic A. thaliana lines and WT plants following the infection by different pathogens. Collectively, the results indicated that VqWRKY52 plays essential roles in the SA dependent signal transduction pathway and that it can enhance the hypersensitive response cell death triggered by microbial pathogens.

  1. Rhizobacteria-mediated induced systemic resistance (ISR) in Arabidopsis is not associated with a direct effect on expression of known defense-related genes but stimulates the expression of the jasmonate-inducible gene Atvsp upon challenge.

    Science.gov (United States)

    van Wees, S C; Luijendijk, M; Smoorenburg, I; van Loon, L C; Pieterse, C M

    1999-11-01

    Selected strains of nonpathogenic rhizobacteria from the genus Pseudomonas are capable of eliciting broad-spectrum induced systemic resistance (ISR) in plants that is phenotypically similar to pathogen-induced systemic acquired resistance (SAR). In Arabidopsis, the ISR pathway functions independently of salicylic acid (SA) but requires responsiveness to jasmonate and ethylene. Here, we demonstrate that known defense-related genes, i.e. the SA-responsive genes PR-1, PR-2, and PR-5, the ethylene-inducible gene Hel, the ethylene- and jasmonate-responsive genes ChiB and Pdf1.2, and the jasmonate-inducible genes Atvsp, Lox1, Lox2, Pall, and Pin2, are neither induced locally in the roots nor systemically in the leaves upon induction of ISR by Pseudomonas fluorescens WCS417r. In contrast, plants infected with the virulent leaf pathogen Pseudomonas syringae pv. tomato (Pst) or expressing SAR induced by preinfecting lower leaves with the avirulent pathogen Pst(avrRpt2) exhibit elevated expression levels of most of the defense-related genes studied. Upon challenge inoculation with Pst, PR gene transcripts accumulated to a higher level in SAR-expressing plants than in control-treated and ISR-expressing plants, indicating that SAR involves potentiation of SA-responsive PR gene expression. In contrast, pathogen challenge of ISR-expressing plants led to an enhanced level of Atvsp transcript accumulation. The otherjasmonate-responsive defense-related genes studied were not potentiated during ISR, indicating that ISR is associated with the potentiation of specific jasmonate-responsive genes.

  2. Reference: 20 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available erial pathogens to host cells. Plants express disease resistance (R) proteins that respond specifically to a... particular type III effector by activating immune responses. We demonstrated previously that two unre...lated type III effectors from Pseudomonas syringae target and modify the Arabidopsis RIN4 protein. Here..., we show that AvrRpt2, a third, unrelated type III effector, also targets RIN4 and induces ...its posttranscriptional disappearance. This effect is independent of the presence

  3. Overexpression of URO Gene Enhances Drought Resistance in Arabidopsis%过量表达URO基因提高拟南芥的抗旱能力

    Institute of Scientific and Technical Information of China (English)

    庞静洋; 倪伟平; 杨扬; 徐艳飞; 李玲; 杨美良; 李小方; 孙越

    2013-01-01

    拟南芥uro突变体中由于URO (UPRIGHT ROSETTE)基因的过量表达导致生长素含量明显提高.本文结果表明,uro突变体的抗旱能力明显强于野生型,但uro突变体的根长、表皮毛数目以及离体叶的脱水速度都没有优于野生型.uro突变体对外源ABA不敏感,且在uro突变体中ABA响应基因的表达与野生型相比显著推迟.另外,表型分析表明uro突变体的营养生长延长,植株衰老延迟,特别是经过渗透胁迫后,uro植株内的丙二醛含量低于野生型.由此可见,URO基因的过量表达使uro突变体通过ABA非依赖途径提高了抗旱能力,而且uro突变体衰老延迟可能与其干旱抗性提高有关.%Arabidopsis uro mutant has higher IAA content than wild-type plants because of UROSETTE) gene overexpression.In this study,the results showed that uro mutant displayed improved drought tolerance compared to wild type.However,no evidence showed uro mutant had any drought tolerance related phenotypes such as root length,number of trichomes and the speed of cellular dehydration of leaf explants.In addition,uro mutant exhibited decreased sensitivity to exogenous abscisic acid (ABA).At the same time,the enhanced expression of ABA-responsive genes in uro mutant was delayed obviously relative to wild type after ABA treatment.On the other hand,uro mutant has prolonged vegetable growth and delayed senescence.Especially after osmotic stress treatment,there was much less malondialdehyde (MDA) in uro mutant than in wild type.These results indicate that overexpression of URO gene enhances drought tolerance of uro mutant through an ABA-independent pathway,and the delayed senescence of uro mutant may relate to its high drought tolerance.

  4. No Silver Bullet – Canonical Poly(ADP-Ribose) Polymerases (PARPs) Are No Universal Factors of Abiotic and Biotic Stress Resistance of Arabidopsis thaliana

    Science.gov (United States)

    Rissel, Dagmar; Heym, Peter P.; Thor, Kathrin; Brandt, Wolfgang; Wessjohann, Ludger A.; Peiter, Edgar

    2017-01-01

    Abiotic and biotic stress can have a detrimental impact on plant growth and productivity. Hence, there is a substantial demand for key factors of stress responses to improve yield stability of crops. Members of the poly(ADP-ribose)polymerase (PARP) protein family, which post-translationally modify (PARylate) nuclear proteins, have been suggested as such universal determinants of plant stress responses. A role under abiotic stress has been inferred from studies in which a genetic or, more commonly, pharmacological inhibition of PARP activity improved the performance of stressed plants. To further elucidate the role of PARP proteins under stress, T-DNA knockout mutants for the three Arabidopsis thaliana PARP genes were subjected to drought, osmotic, salt, and oxidative stress. To exclude a functional redundancy, which was indicated by a transcriptional upregulation of the remaining parp genes, a parp triple mutant was generated. Surprisingly, parp mutant plants did not differ from wild type plants in any of these stress experiments, independent from the number of PARP genes mutated. The parp triple mutant was also analyzed for callose formation in response to the pathogenassociated molecular pattern flg22. Unexpectedly, callose formation was unaltered in the mutant, albeit pharmacological PARP inhibition robustly blocked this immune response, confirming previous reports. Evidently, pharmacological inhibition appears to be more robust than the abolition of all PARP genes, indicating the presence of so-far undescribed proteins with PARP activity. This was supported by the finding that protein PARylation was not absent, but even increased in the parp triple mutant. Candidates for novel PARP-inhibitor targets may be found in the SRO protein family. These proteins harbor a catalytic PARP-like domain and are centrally involved in stress responses. Molecular modeling analyses, employing animal PARPs as templates, indeed indicated a capability of the SRO proteins RCD1 and

  5. Reference: 186 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available nce rooting during propagation. To better understand the role of IBA, we isolated Arabidopsis IBA-response (ibr) mutants that display...t, whereas acx1 acx3 and acx1 acx5 double mutants display enhanced IBA resistance...cx1 acx2 double mutants display enhanced IBA resistance and are sucrose dependent during seedling developmen...tive in ACX1, ACX3, or ACX4 have reduced fatty acyl-CoA oxidase activity on specific substrates. Moreover, a

  6. Arabidopsis thaliana cdd1 mutant uncouples the constitutive activation of salicylic acid signalling from growth defects

    NARCIS (Netherlands)

    Swain, S.; Roy, S.; Shah, J.; Wees, S.C.M. van; Pieterse, C.M.J.; Nandi, A.K.

    2011-01-01

    Arabidopsis genotypes with a hyperactive salicylic acidmediated signalling pathway exhibit enhanced disease resistance, which is often coupled with growth and developmental defects, such as dwarfing and spontaneous necrotic lesions on the leaves, resulting in reduced biomass yield. In this article,

  7. Enhanced disease resistance to Botrytis cinerea in myb46 Arabidopsis plants is associated to an early down-regulation of CesA genes.

    Science.gov (United States)

    Ramírez, Vicente; García-Andrade, Javier; Vera, Pablo

    2011-06-01

    The cell wall is a protective barrier of paramount importance for the survival of plant cells. Monitoring the integrity of cell wall allows plants to quickly activate defence pathways to minimize pathogen entry and reduce the spread of disease. Counterintuitively, however, pharmacological effects as well as genetic lesions that affect cellulose biosynthesis and content confer plants with enhanced resistance against necrotrophic fungi. This kind of pathogens target cellulose for degradation to facilitate penetration and to generate glucose units as a food source. Our results points towards the existence of a transcriptional reprogramming mechanism in genes encoding cellulose synthases (CesAs) that occurs very soon after Botrytis cinerea attack and that results in a temporarily shut down of some CesA genes. Interestingly, the observed coordinated down-regulation of CesA genes is more pronounced, and occurs earlier, in myb46 mutant plants. In the resistant myb46 plants, pathogen infection induces transient down-regulation of CesA genes that concurs with a selective transcriptional reprogramming in a set of genes encoding structural cell wall proteins and extracellular remodelling enzymes. Together with previous indications, our results favour the hypothesis that CesAs are part of a surveillance system of the cell wall integrity that senses the presence of a pathogen and transduces that signal into a rapid transcriptional reprogramming of the affected cell.

  8. Reference: 517 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available d isolated aleurone layers of Arabidopsis (Arabidopsis thaliana) were used in experiments designed to iden...tify components of the Arabidopsis seed that contribute to seed dormancy and to lea

  9. Diuretics Prime Plant Immunity in Arabidopsis thaliana

    Science.gov (United States)

    Noutoshi, Yoshiteru; Ikeda, Mika; Shirasu, Ken

    2012-01-01

    Plant activators are agrochemicals that activate the plant immune system, thereby enhancing disease resistance. Due to their prophylactic and durable effects on a wide spectrum of diseases, plant activators can provide synergistic crop protection when used in combination with traditional pest controls. Although plant activators have achieved great success in wet-rice farming practices in Asia, their use is still limited. To isolate novel plant activators applicable to other crops, we screened a chemical library using a method that can selectively identify immune-priming compounds. Here, we report the isolation and characterization of three diuretics, bumetanide, bendroflumethiazide and clopamide, as immune-priming compounds. These drugs upregulate the immunity-related cell death of Arabidopsis suspension-cultured cells induced with an avirulent strain of Pseudomonas syringae pv. tomato in a concentration-dependent manner. The application of these compounds to Arabidopsis plants confers disease resistance to not only the avirulent but also a virulent strain of the pathogen. Unlike salicylic acid, an endogenous phytohormone that governs disease resistance in response to biotrophic pathogens, the three diuretic compounds analyzed here do not induce PR1 or inhibit plant growth, showing potential as lead compounds in a practical application. PMID:23144763

  10. Diuretics prime plant immunity in Arabidopsis thaliana.

    Directory of Open Access Journals (Sweden)

    Yoshiteru Noutoshi

    Full Text Available Plant activators are agrochemicals that activate the plant immune system, thereby enhancing disease resistance. Due to their prophylactic and durable effects on a wide spectrum of diseases, plant activators can provide synergistic crop protection when used in combination with traditional pest controls. Although plant activators have achieved great success in wet-rice farming practices in Asia, their use is still limited. To isolate novel plant activators applicable to other crops, we screened a chemical library using a method that can selectively identify immune-priming compounds. Here, we report the isolation and characterization of three diuretics, bumetanide, bendroflumethiazide and clopamide, as immune-priming compounds. These drugs upregulate the immunity-related cell death of Arabidopsis suspension-cultured cells induced with an avirulent strain of Pseudomonas syringae pv. tomato in a concentration-dependent manner. The application of these compounds to Arabidopsis plants confers disease resistance to not only the avirulent but also a virulent strain of the pathogen. Unlike salicylic acid, an endogenous phytohormone that governs disease resistance in response to biotrophic pathogens, the three diuretic compounds analyzed here do not induce PR1 or inhibit plant growth, showing potential as lead compounds in a practical application.

  11. Reference: 288 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available ly of integral membrane transporters function in cellular detoxification, cell-to-cell signaling, and channel regulation. More re...cently, members of the multidrug resistance P-glycoprotein (...n in both monocots and dicots. Here, we report that the Arabidopsis thaliana MDR/PGP PGP4 functions in the basipetal redire...ction of auxin from the root tip. Reporter gene studies showed tha...l as lateral root formation were reduced in pgp4 mutants compared with the wild type. pgp4 exhibited re

  12. Reference: 624 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available lexin 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 C...YP79B2 and CYP79B3. The remaining biosynthetic steps are unknown except for the last step, which is conversi...on of dihydrocamalexic acid to camalexin by CYP71B15 (PAD3). This article reports

  13. The quantitative basis of the Arabidopsis innate immune system to endemic pathogens depends on pathogen genetics

    DEFF Research Database (Denmark)

    Corwin, Jason A; Copeland, Daniel; Feusier, Julie;

    2016-01-01

    The most established model of the eukaryotic innate immune system is derived from examples of large effect monogenic quantitative resistance to pathogens. However, many host-pathogen interactions involve many genes of small to medium effect and exhibit quantitative resistance. We used...... the Arabidopsis-Botrytis pathosystem to explore the quantitative genetic architecture underlying host innate immune system in a population of Arabidopsis thaliana. By infecting a diverse panel of Arabidopsis accessions with four phenotypically and genotypically distinct isolates of the fungal necrotroph B....... cinerea, we identified a total of 2,982 genes associated with quantitative resistance using lesion area and 3,354 genes associated with camalexin production as measures of the interaction. Most genes were associated with resistance to a specific Botrytis isolate, which demonstrates the influence...

  14. Reference: 774 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available an essential gene, the disruption of which causes embryonic lethality. Plants carrying a hypomorphic smg7 mu...e progression from anaphase to telophase in the second meiotic division in Arabidopsis. Arabidopsis SMG7 is

  15. Reference: 398 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available plays attenuated chloroplast movements under intermediate and high light intensitie...hese movements. In this work, we describe plastid movement impaired 2 (pmi2), a mutant in Arabidopsis (Arabidopsis thaliana) that dis

  16. Reference: 173 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available mical approaches to elucidate the action mechanisms of sirtinol in Arabidopsis. A...tic and chemical analyses of the action mechanisms of sirtinol in Arabidopsis. 8 3129-34 15710899 2005 Feb P

  17. Reference: 718 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available displayed a moderate but significant decrease in germination in the presence of D...NA damage. This report links Ubc13-Uev with functions in DNA damage response in Arabidopsis. Arabidopsis UEV

  18. Arabidopsis CDS blastp result: AK068856 [KOME

    Lifescience Database Archive (English)

    Full Text Available eme oxygenase (HY1) [Arabidopsis thaliana] GI:4877362, heme oxygenase 1 [Arabidopsis thaliana] GI:4530591 GB:AF132475; annotation upd...ated per Seth J. Davis at University of Wisconsin-Madison 3e-90 ...

  19. Arabidopsis CDS blastp result: AK104955 [KOME

    Lifescience Database Archive (English)

    Full Text Available B:AF132475; annotation updated per Seth J. Davis at University of Wisconsin-Madison 3e-90 ... ...heme oxygenase (HY1) [Arabidopsis thaliana] GI:4877362, heme oxygenase 1 [Arabidopsis thaliana] GI:4530591 G

  20. Reference: 110 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available on process. Our study shows that an Arabidopsis SNM protein, although structurally closer to the SNM1/PSO2 members, shares some prope...rties with ARTEMIS but also has novel characteristics. Arabidopsis plants defective

  1. Non-host defense response in a novel Arabidopsis-Xanthomonas citri subsp. citri pathosystem.

    Directory of Open Access Journals (Sweden)

    Chuanfu An

    Full Text Available Citrus canker, caused by Xanthomonas citri subsp. citri (Xcc, is one of the most destructive diseases of citrus. Progress of breeding citrus canker-resistant varieties is modest due to limited resistant germplasm resources and lack of candidate genes for genetic manipulation. The objective of this study is to establish a novel heterologous pathosystem between Xcc and the well-established model plant Arabidopsis thaliana for defense mechanism dissection and resistance gene identification. Our results indicate that Xcc bacteria neither grow nor decline in Arabidopsis, but induce multiple defense responses including callose deposition, reactive oxygen species and salicylic aicd (SA production, and defense gene expression, indicating that Xcc activates non-host resistance in Arabidopsis. Moreover, Xcc-induced defense gene expression is suppressed or attenuated in several well-characterized SA signaling mutants including eds1, pad4, eds5, sid2, and npr1. Interestingly, resistance to Xcc is compromised only in eds1, pad4, and eds5, but not in sid2 and npr1. However, combining sid2 and npr1 in the sid2npr1 double mutant compromises resistance to Xcc, suggesting genetic interactions likely exist between SID2 and NPR1 in the non-host resistance against Xcc in Arabidopsis. These results demonstrate that the SA signaling pathway plays a critical role in regulating non-host defense against Xcc in Arabidopsis and suggest that the SA signaling pathway genes may hold great potential for breeding citrus canker-resistant varieties through modern gene transfer technology.

  2. Environmental History Modulates Arabidopsis Pattern-Triggered Immunity in a HISTONE ACETYLTRANSFERASE1-Dependent Manner.

    Science.gov (United States)

    Singh, Prashant; Yekondi, Shweta; Chen, Po-Wen; Tsai, Chia-Hong; Yu, Chun-Wei; Wu, Keqiang; Zimmerli, Laurent

    2014-06-01

    In nature, plants are exposed to a fluctuating environment, and individuals exposed to contrasting environmental factors develop different environmental histories. Whether different environmental histories alter plant responses to a current stress remains elusive. Here, we show that environmental history modulates the plant response to microbial pathogens. Arabidopsis thaliana plants exposed to repetitive heat, cold, or salt stress were more resistant to virulent bacteria than Arabidopsis grown in a more stable environment. By contrast, long-term exposure to heat, cold, or exposure to high concentrations of NaCl did not provide enhanced protection against bacteria. Enhanced resistance occurred with priming of Arabidopsis pattern-triggered immunity (PTI)-responsive genes and the potentiation of PTI-mediated callose deposition. In repetitively stress-challenged Arabidopsis, PTI-responsive genes showed enrichment for epigenetic marks associated with transcriptional activation. Upon bacterial infection, enrichment of RNA polymerase II at primed PTI marker genes was observed in environmentally challenged Arabidopsis. Finally, repetitively stress-challenged histone acetyltransferase1-1 (hac1-1) mutants failed to demonstrate enhanced resistance to bacteria, priming of PTI, and increased open chromatin states. These findings reveal that environmental history shapes the plant response to bacteria through the development of a HAC1-dependent epigenetic mark characteristic of a primed PTI response, demonstrating a mechanistic link between the primed state in plants and epigenetics.

  3. Resistance to Powdery Mildews

    DEFF Research Database (Denmark)

    Siwoszek, Agnieszka Izabela

    how the basic resistance components contribute to resistance against powdery mildews. Furthermore, I propose an alternative strategy of achieving resistance to barley powdery mildew by application of peptide aptamers. Peptide aptamers are small proteins selected to specifically target conserved Yx......C motif of barley powdery mildew effectors. I present a proof-of-concept study in Arabidopsis, where overexpression of peptide aptamers significantly reduced the susceptibility to barley powdery mildew. Moreover, I set the discovery in a bigger context by summarizing genetic engineering technologies...

  4. The quantitative basis of the Arabidopsis innate immune system to endemic pathogens depends on pathogen genetics

    DEFF Research Database (Denmark)

    Corwin, Jason A; Copeland, Daniel; Feusier, Julie

    2016-01-01

    the Arabidopsis-Botrytis pathosystem to explore the quantitative genetic architecture underlying host innate immune system in a population of Arabidopsis thaliana. By infecting a diverse panel of Arabidopsis accessions with four phenotypically and genotypically distinct isolates of the fungal necrotroph B...... of pathogen genetic variation in analyzing host quantitative resistance. While known resistance genes, such as receptor-like kinases (RLKs) and nucleotide-binding site leucine-rich repeat proteins (NLRs), were found to be enriched among associated genes, they only account for a small fraction of the total......, including defense hormone signaling and ROS production, as well as novel processes, such as leaf development. Validation of single gene T-DNA knockouts in a Col-0 background demonstrate a high success rate (60%) when accounting for differences in environmental and Botrytis genetic variation. This study...

  5. Arabidopsis thaliana peroxidase N

    DEFF Research Database (Denmark)

    Mirza, Osman Asghar; Henriksen, A; Ostergaard, L

    2000-01-01

    The structure of the neutral peroxidase from Arabidopsis thaliana (ATP N) has been determined to a resolution of 1.9 A and a free R value of 20.5%. ATP N has the expected characteristic fold of the class III peroxidases, with a C(alpha) r.m.s.d. of 0.82 A when compared with horseradish peroxidase C...... (HRP C). HRP C is 54% identical to ATP N in sequence. When the structures of four class III plant peroxidases are superimposed, the regions with structural differences are non-randomly distributed; all are located in one half of the molecule. The architecture of the haem pocket of ATP N is very similar...... to that of HRP C, in agreement with the low small-molecule substrate specificity of all class III peroxidases. The structure of ATP N suggests that the pH dependence of the substrate turnover will differ from that of HRP C owing to differences in polarity of the residues in the substrate-access channel. Since...

  6. Chromosomal proteins of Arabidopsis thaliana.

    Science.gov (United States)

    Moehs, C P; McElwain, E F; Spiker, S

    1988-07-01

    In plants with large genomes, each of the classes of the histones (H1, H2A, H2B, H3 and H4) are not unique polypeptides, but rather families of closely related proteins that are called histone variants. The small genome and preponderance of single-copy DNA in Arabidopsis thaliana has led us to ask if this plant has such families of histone variants. We have thus isolated histones from Arabidopsis and analyzed them on four polyacrylamide gel electrophoretic systems: an SDS system; an acetic acid-urea system; a Triton transverse gradient system; and a two-dimensional system combining SDS and Triton-acetic acid-urea systems. This approach has allowed us to identify all four of the nucleosomal core histones in Arabidopsis and to establish the existence of a set of H2A and H2B variants. Arabidopsis has at least four H2A variants and three H2B variants of distinct molecular weights as assessed by electrophoretic mobility on SDS-polyacrylamide gels. Thus, Arabidopsis displays a diversity in these histones similar to the diversity displayed by plants with larger genomes such as wheat.The high mobility group (HMG) non-histone chromatin proteins have attracted considerable attention because of the evidence implicating them as structural proteins of transcriptionally active chromatin. We have isolated a group of non-histone chromatin proteins from Arabidopsis that meet the operational criteria to be classed as HMG proteins and that cross-react with antisera to HMG proteins of wheat.

  7. Subcellular localization and resistance to Botrytis cinerea of a new type lipid transfer protein AtDHyPRP1 from Arabidopsis thaliana%拟南芥新型脂转移蛋白AtDHyPRP1的亚细胞定位及其对灰霉菌的抗性

    Institute of Scientific and Technical Information of China (English)

    张晨; 李岚; 徐子勤

    2012-01-01

    Genetic transformation was adopted to analyze the subcellular localization and the resistance to fungal pathogens of Arabidopsis lipid transfer protein AtDHyPRPl. The coding sequence of AtDHyPRPl amplified by PCR from Ws ecotype was used to construct the plant binary expression vector pRIlOl-AN-AtDHyPRPl and the fusion expression vector pCAMBIA1302-AtDHyPRPl-GFP. Transgenic tobacco and Arabidopsis plants were produced by leaf disc and floral dip protocols, respectively. AtDHyPRPl could improve the resistance of tobacco to Botrytis cinerea remarkably and the infection sites on transgenic tobacco leaves accumulated large amounts of H2O2. Observation under laser scanning confocal microscope showed that AtDHyPRPl was localized to cell surface. It suggested that AtDHyPRPl might play special function after secretion to outside of the cell and was involved in plant defense system against pathogens.%通过遗传转化技术研究了拟南芥脂转移蛋白AtDHyPRP1在细胞中的定位及其对真菌病原体的抗性.采用PCR方法从拟南芥Ws生态型克隆了AtDHyPRP1基因,构建产生pRI101-AN-AtDHyPRP1植物双元表达载体和pCAMBIA 1302-AtDHyPRP1-GFP融合表达载体,经农杆菌介导的叶盘和浸花法得到烟草和拟南芥转基因植株.AtDHyPRP1基因能够明显增加烟草对灰霉菌的抗性,转AtDHyPRP1烟草叶片的被侵染部位有大量H2O2积累,激光共聚焦显微观察发现AtDHyPRP1蛋白定位于细胞表面.说明AtDHyPRP1蛋白在合成后被分泌到细胞外执行特殊的功能,与植物抗病防御机制有关.

  8. Folic acid induces salicylic acid-dependent immunity in Arabidopsis and enhances susceptibility to Alternaria brassicicola.

    Science.gov (United States)

    Wittek, Finni; Kanawati, Basem; Wenig, Marion; Hoffmann, Thomas; Franz-Oberdorf, Katrin; Schwab, Wilfried; Schmitt-Kopplin, Philippe; Vlot, A Corina

    2015-08-01

    Folates are essential for one-carbon transfer reactions in all organisms and contribute, for example, to de novo DNA synthesis. Here, we detected the folate precursors 7,8-dihydropteroate (DHP) and 4-amino-4-deoxychorismate (ADC) in extracts from Arabidopsis thaliana plants by Fourier transform ion cyclotron resonance-mass spectrometry. The accumulation of DHP, but not ADC, was induced after infection of plants with Pseudomonas syringae delivering the effector protein AvrRpm1. Application of folic acid or the DHP precursor 7,8-dihydroneopterin (DHN) enhanced resistance in Arabidopsis to P. syringae and elevated the transcript accumulation of the salicylic acid (SA) marker gene pathogenesis-related1 in both the treated and systemic untreated leaves. DHN- and folic acid-induced systemic resistance was dependent on SA biosynthesis and signalling. Similar to SA, folic acid application locally enhanced Arabidopsis susceptibility to the necrotrophic fungus Alternaria brassicicola. Together, the data associate the folic acid pathway with innate immunity in Arabidopsis, simultaneously activating local and systemic SA-dependent resistance to P. syringae and suppressing local resistance to A. brassicicola.

  9. The Impact of the Absence of Aliphatic Glucosinolates on Insect Herbivory in Arabidopsis

    NARCIS (Netherlands)

    Beekwilder, J.; van Leeuwen, W.; Van Dam, N.M.; Bertossi, M.; Grandi, V.; Mizzi, L.; Soloviev, M.; Szabados, L.; Molthoff, J.W.; Schipper, B.; Verbocht, H.; de Vos, R.C.H.; Morandini, P.; Aarts, M.G.M.; Bovy, A.

    2008-01-01

    Aliphatic glucosinolates are compounds which occur in high concentrations in Arabidopsis thaliana and other Brassicaceae species. They are important for the resistance of the plant to pest insects. Previously, the biosynthesis of these compounds was shown to be regulated by transcription factors MYB

  10. Identification of genes affecting the response of tomato and Arabidopsis upon powdery mildew infection

    NARCIS (Netherlands)

    Gao, D.

    2014-01-01

      Many plant species are hosts of powdery mildew fungi, including Arabidopsis and economically important crops such as wheat, barley and tomato. Resistance has been explored using induced mutagenesis and natural variation in the plant species. The isolated genes encompass loss-of-function susc

  11. 过表达拟南芥点突变乙酰羟酸合成酶基因改变植物对缬氨酸的抗性及增强缬氨酸合成%Overexpression of the PointMutated Acetohydroxyacid Synthase Alters Resis-tance to Valine and Enhances Production of Valine inArabidopsis

    Institute of Scientific and Technical Information of China (English)

    赵菲佚; 焦成瑾; 王太术; 田春芳; 谢尚强; 刘亚萍

    2015-01-01

    拟南芥乙酰羟酸合成酶(acetohydroxyacid synthase, AHAS)在支链氨基酸合成中具有重要的作用。为考察AHAS不同亚基关键位点突变对植物缬氨酸抗性与缬氨酸合成的影响,对AHAS大小亚基上特定位点进行体外突变,构建AHAS点突变过表达转基因植物,研究AHAS不同亚基点突变转基因植物对缬氨酸抗性及其合成的影响。研究结果表明: AHAS小亚基G88D突变解除了终端产物对该酶的反馈抑制作用,使转基因植物缬氨酸含量提高。大亚基E305D突变增强小亚基G88D突变效应,而大亚基E482D突变对G88D突变具有相反的作用。AHAS全酶E305DG88D双突变转基因植物较E482DG88D具有更强的缬氨酸抗性表型和更高的缬氨酸含量。这些结果提示AHAS大小亚基间存在着相互作用,大小亚基不同位点突变对AHAS全酶活性具有不同的影响。%Acetohydroxyacid synthase (AHAS) plays a pivotal role in the synthesis of brahched-chain amino acids (BCAAs) inArabidopsis. To investigate effects of various speciifc mutated sites harboring in the large and small subunits of AHAS on resistance to valine and production of valine inArabidopsis, transgenic plants overexpressing the point mutated AHAS were generated by site-directed mutagenesis, and the phenotype of re-sistance to valine and production of valine of the transgenic plants were evaluatedin planta. The results showed that the G88D mutation in the small unit of AHAS abolished the feedback-resistant of valine to AHAS and this mutation resulted in increase of valine in the transgenic plants. The E305D mutation in the large unit of AHAS strengthens the effect of the G88D mutation. Interestingly, the E482D mutation in the large unit of AHAS acts antagonistically on the G88D mutation in resistance to valine and production of valine in transgenic plants. Compared with the combined double E482DG88D AHAS mutant transgenic plants, the E305DG88D AHAS transgenic plants exhibited the

  12. Transmembrane Calcium and Hydrogen Ion Flux Involved in Insect-Resistant Defense Induced by Linalool in Arabidopsis thaliana L.%跨膜Ca2+和H+离子流参与里那醇诱导的拟南芥中抗虫防御反应

    Institute of Scientific and Technical Information of China (English)

    张瑞鑫; 高海波; 闫素丽; 张婷; 刘蕾; 沈应柏

    2014-01-01

    里那醇可诱导植物产生防御物质从而阻止昆虫及病原菌的伤害。本文以拟南芥植株为材料,研究了里那醇对小菜蛾取食选择性的影响,测定了里那醇处理下小菜蛾生长量及存活率。采用非损伤微测技术分别检测了里那醇熏蒸及未熏蒸拟南芥对小菜蛾口腔分泌物及里那醇瞬时处理的植株叶片跨膜Ca2+和H+流的变化。结果表明,小菜蛾幼虫对里那醇熏蒸处理的植株选择性较差,用里那醇熏蒸后的拟南芥植株喂养小菜蛾幼虫,幼虫的生长量及存活率均低于对照组。小菜蛾口腔分泌物和里那醇熏蒸处理均导致拟南芥叶组织跨膜Ca2+和H+离子迅速外流,且小菜蛾口腔分泌物的作用更大。而对照中Ca2+和H+离子流整体均无明显变化。研究结果证明里那醇作为防御信号参与了拟南芥对昆虫的防御反应,叶组织跨膜Ca2+和H+离子流变化可能是拟南芥识别昆虫口腔分泌物与里那醇两种不同刺激的初始信号。%It is documented that linalool would induce plants to produce defense substances to prevent the harm from insects and pathogens. To analyze the early events and effects on the performances on herbivorous insects caused by linalool, Arabidopsis thaliana and Plutella xylostella were used as materials and net ion lfuxes of H+and Ca2+, as well as selectivity, growth rate, survival rate of P. xylostella feeding on Arabidopsis seedlings with or without linalool fumigating were analyzed. The results indicated that eflfuxes of Ca2+and H+were rapidly induced by linalool exposure and insect oral secretions whereas insect oral secretions resulted in stronger effects. Performances of P. xylostella were affected by linalool fumigating and lower selection, growth and survival rate were observed on linalool fumigated seedlings. Therefore, linalool might participate in insect resistance as defense substances, Ca2+and H+lfux change might be primal signals in

  13. Exploiting Natural Variation in Arabidopsis

    NARCIS (Netherlands)

    Molenaar, J.A.; Keurentjes, J.J.B.

    2014-01-01

    Natural variation for many traits is present within the species Arabidopsis thaliana . This chapter describes the use of natural variation to elucidate genes underlying the regulation of quantitative traits. It deals with the development and use of mapping populations, the detection and handling of

  14. Exploiting natural variation in Arabidopsis

    NARCIS (Netherlands)

    J.A. Molenaar; J.J.B. Keurentjes

    2014-01-01

    Natural variation for many traits is present within the species Arabidopsis thaliana. This chapter describes the use of natural variation to elucidate genes underlying the regulation of quantitative traits. It deals with the development and use of mapping populations, the detection and handling of g

  15. The Functions of RNA-Dependent RNA Polymerases in Arabidopsis

    Science.gov (United States)

    Willmann, Matthew R.; Endres, Matthew W.; Cook, Rebecca T.; Gregory, Brian D.

    2011-01-01

    One recently identified mechanism that regulates mRNA abundance is RNA silencing, and pioneering work in Arabidopsis thaliana and other genetic model organisms helped define this process. RNA silencing pathways are triggered by either self-complementary fold-back structures or the production of double-stranded RNA (dsRNA) that gives rise to small RNAs (smRNAs) known as microRNAs (miRNAs) or small-interfering RNAs (siRNAs). These smRNAs direct sequence-specific regulation of various gene transcripts, repetitive sequences, viruses, and mobile elements via RNA cleavage, translational inhibition, or transcriptional silencing through DNA methylation and heterochromatin formation. Early genetic screens in Arabidopsis were instrumental in uncovering numerous proteins required for these important regulatory pathways. Among the factors identified by these studies were RNA-dependent RNA polymerases (RDRs), which are proteins that synthesize siRNA-producing dsRNA molecules using a single-stranded RNA (ssRNA) molecule as a template. Recently, a growing body of evidence has implicated RDR-dependent RNA silencing in many different aspects of plant biology ranging from reproductive development to pathogen resistance. Here, we focus on the specific functions of the six Arabidopsis RDRs in RNA silencing, their ssRNA substrates and resulting RDR-dependent smRNAs, and the numerous biological functions of these proteins in plant development and stress responses. PMID:22303271

  16. Mapping moves on Arabidopsis

    OpenAIRE

    Kloth, K.J.

    2016-01-01

                    Aphids are pest insects in a wide variety of crops. They penetrate the host plant in order to feed on the sugar-rich phloem sap. Apart from the removal of nutrients from the host, they can transmit plant viruses. To control aphid populations and virus transmission in agriculture, insecticides are applied on a large scale with often negative effects on biodiversity. Improvement of crop resistance to aphids would be a more sustainable pes...

  17. Reference: 710 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available n factor family in Arabidopsis (Arabidopsis thaliana). Treatment with abscisic acid (ABA) induced AtMYB44 tr...anscript accumulation within 30 min. The gene was also activated under various abiotic stre...sses, such as dehydration, low temperature, and salinity. In transgenic Arabidopsis carrying an At...MYB44 promoter-driven beta-glucuronidase (GUS) construct, strong GUS activity was observed in the vasculature... and leaf epidermal guard cells. Transgenic Arabidopsis overexpressing AtMYB44 is more

  18. Evidences for involvement of endogenous cAMP in Arabidopsis defense responses to Verticillium toxins

    Institute of Scientific and Technical Information of China (English)

    Jing JIANG; Ling Wen FAN; Wei Hua WU

    2005-01-01

    Although there were reports suggesting the involvement of endogenous cAMP in plant defense signaling cascades,there is no direct evidence supporting this notion yet and the detailed mechanism is unclear. In the present study, we have used pathogenic fungi Verticillium dahliae and Arabidopsis plants as a model system of plant-microb interaction to demonstrate the function of endogenous cAMP in Arabidopsis defense responses. Both V. dahliae inoculation and Verticillium toxins injection induced typical "wilt" symptoms in Arabidopsis seedlings. When either 8-Br-AMP (a membrane permeable cAMP analogue) or salicylic acid (SA) was applied to Arabidopsis, the plants became resistant to V. dahliae toxins. However, addition of 8-Br-AMP did not increase the resistance of Arabidopsis transgenic plants deficient in SA to the toxins, suggesting that cAMP might act upstream of SA in plant defense signaling pathway.Indeed, 8-Br-cAMP and forskolin, an activator of adenylyl cyclase, significantly stimulated the endogenous SA level in plants, whereas DDA, an inhibitor of adenylyl cyclase dramatically reduced toxin-induced SA increase. Both the endogenous cAMP and SA increased significantly in Arabidopsis seedlings treated with toxins. Furthermore, transcription level of pathogenesis-related protein 1 gene (PR1) was strongly induced by both 8-Br-cAMP and the toxin treatment. Taken together, our data demonstrate that endogenous cAMP is involved in plant defense responses against Verticilliumsecreted toxins by regulating the production of the known signal SA in plant defense pathway.

  19. An International Bioinformatics Infrastructure to Underpin the Arabidopsis Community

    Science.gov (United States)

    The future bioinformatics needs of the Arabidopsis community as well as those of other scientific communities that depend on Arabidopsis resources were discussed at a pair of recent meetings held by the Multinational Arabidopsis Steering Committee (MASC) and the North American Arabidopsis Steering C...

  20. Arabidopsis CDS blastp result: AK240652 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK240652 J023098G11 At5g63090.2 68418.m07919 LOB domain protein / lateral organ boundaries... protein (LOB) identical to LOBa [Arabidopsis thaliana] GI:17484100, SP|Q9FML4 LATERAL ORGAN BOUNDARIES protein {Arabidopsis thaliana} 1e-13 ...

  1. Arabidopsis CDS blastp result: AK241761 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241761 J065205C18 At5g63090.1 68418.m07918 LOB domain protein / lateral organ boundaries... protein (LOB) identical to LOBa [Arabidopsis thaliana] GI:17484100, SP|Q9FML4 LATERAL ORGAN BOUNDARIES protein {Arabidopsis thaliana} 5e-32 ...

  2. Arabidopsis CDS blastp result: AK240652 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK240652 J023098G11 At5g63090.1 68418.m07918 LOB domain protein / lateral organ boundaries... protein (LOB) identical to LOBa [Arabidopsis thaliana] GI:17484100, SP|Q9FML4 LATERAL ORGAN BOUNDARIES protein {Arabidopsis thaliana} 1e-13 ...

  3. Arabidopsis CDS blastp result: AK240652 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK240652 J023098G11 At5g63090.4 68418.m07921 LOB domain protein / lateral organ boundaries... protein (LOB) identical to LOBa [Arabidopsis thaliana] GI:17484100, SP|Q9FML4 LATERAL ORGAN BOUNDARIES protein {Arabidopsis thaliana} 1e-13 ...

  4. Arabidopsis CDS blastp result: AK241761 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241761 J065205C18 At5g63090.3 68418.m07920 LOB domain protein / lateral organ boundaries... protein (LOB) identical to LOBa [Arabidopsis thaliana] GI:17484100, SP|Q9FML4 LATERAL ORGAN BOUNDARIES protein {Arabidopsis thaliana} 5e-32 ...

  5. Arabidopsis CDS blastp result: AK241761 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241761 J065205C18 At5g63090.2 68418.m07919 LOB domain protein / lateral organ boundaries... protein (LOB) identical to LOBa [Arabidopsis thaliana] GI:17484100, SP|Q9FML4 LATERAL ORGAN BOUNDARIES protein {Arabidopsis thaliana} 5e-32 ...

  6. Arabidopsis CDS blastp result: AK241761 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241761 J065205C18 At5g63090.4 68418.m07921 LOB domain protein / lateral organ boundaries... protein (LOB) identical to LOBa [Arabidopsis thaliana] GI:17484100, SP|Q9FML4 LATERAL ORGAN BOUNDARIES protein {Arabidopsis thaliana} 5e-32 ...

  7. Arabidopsis CDS blastp result: AK240652 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK240652 J023098G11 At5g63090.3 68418.m07920 LOB domain protein / lateral organ boundaries... protein (LOB) identical to LOBa [Arabidopsis thaliana] GI:17484100, SP|Q9FML4 LATERAL ORGAN BOUNDARIES protein {Arabidopsis thaliana} 1e-13 ...

  8. Arabidopsis CDS blastp result: AK105527 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK105527 001-127-G05 At5g63090.4 LOB domain protein / lateral organ boundaries prot...ein (LOB) identical to LOBa [Arabidopsis thaliana] GI:17484100, SP|Q9FML4 LATERAL ORGAN BOUNDARIES protein {Arabidopsis thaliana} 3e-52 ...

  9. Using "Arabidopsis" Genetic Sequences to Teach Bioinformatics

    Science.gov (United States)

    Zhang, Xiaorong

    2009-01-01

    This article describes a new approach to teaching bioinformatics using "Arabidopsis" genetic sequences. Several open-ended and inquiry-based laboratory exercises have been designed to help students grasp key concepts and gain practical skills in bioinformatics, using "Arabidopsis" leucine-rich repeat receptor-like kinase (LRR…

  10. Arabidopsis CDS blastp result: AK240730 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK240730 J043030K09 At2g32440.1 68415.m03963 ent-kaurenoic acid hydroxylase, putati...ve / cytochrome P450, putative identical to ent-kaurenoic acid hydroxylase / cytochrome P450 CYP88A (GI:1302...1856) [Arabidopsis thaliana]; similar to ent-kaurenoic acid hydroxylase [Arabidopsis thaliana] GI:13021853 2e-11 ...

  11. Arabidopsis CDS blastp result: AK288052 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK288052 J075151I09 At2g32440.1 68415.m03963 ent-kaurenoic acid hydroxylase, putati...ve / cytochrome P450, putative identical to ent-kaurenoic acid hydroxylase / cytochrome P450 CYP88A (GI:1302...1856) [Arabidopsis thaliana]; similar to ent-kaurenoic acid hydroxylase [Arabidopsis thaliana] GI:13021853 6e-14 ...

  12. Arabidopsis CDS blastp result: AK240911 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK240911 J065037E05 At2g32440.1 68415.m03963 ent-kaurenoic acid hydroxylase, putati...ve / cytochrome P450, putative identical to ent-kaurenoic acid hydroxylase / cytochrome P450 CYP88A (GI:1302...1856) [Arabidopsis thaliana]; similar to ent-kaurenoic acid hydroxylase [Arabidopsis thaliana] GI:13021853 4e-22 ...

  13. Arabidopsis CDS blastp result: AK241119 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241119 J065094C22 At2g32440.1 68415.m03963 ent-kaurenoic acid hydroxylase, putati...ve / cytochrome P450, putative identical to ent-kaurenoic acid hydroxylase / cytochrome P450 CYP88A (GI:1302...1856) [Arabidopsis thaliana]; similar to ent-kaurenoic acid hydroxylase [Arabidopsis thaliana] GI:13021853 2e-13 ...

  14. Arabidopsis CDS blastp result: AK243149 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK243149 J100032I21 At2g32440.1 68415.m03963 ent-kaurenoic acid hydroxylase, putati...ve / cytochrome P450, putative identical to ent-kaurenoic acid hydroxylase / cytochrome P450 CYP88A (GI:1302...1856) [Arabidopsis thaliana]; similar to ent-kaurenoic acid hydroxylase [Arabidopsis thaliana] GI:13021853 7e-12 ...

  15. Arabidopsis CDS blastp result: AK241581 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241581 J065181K09 At2g32440.1 68415.m03963 ent-kaurenoic acid hydroxylase, putati...ve / cytochrome P450, putative identical to ent-kaurenoic acid hydroxylase / cytochrome P450 CYP88A (GI:1302...1856) [Arabidopsis thaliana]; similar to ent-kaurenoic acid hydroxylase [Arabidopsis thaliana] GI:13021853 4e-15 ...

  16. Arabidopsis CDS blastp result: AK287479 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK287479 J043023O14 At2g32440.1 68415.m03963 ent-kaurenoic acid hydroxylase, putati...ve / cytochrome P450, putative identical to ent-kaurenoic acid hydroxylase / cytochrome P450 CYP88A (GI:1302...1856) [Arabidopsis thaliana]; similar to ent-kaurenoic acid hydroxylase [Arabidopsis thaliana] GI:13021853 1e-17 ...

  17. Reference: 631 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available ggest that atRZ-1a has a negative impact on seed germination and seedling growth of Arabidopsis under salt o...binding protein, atRZ-1a, has a negative impact on seed germination and seedling growth of Arabidopsis thali

  18. Re-Evaluation of Reportedly Metal Tolerant Arabidopsis thaliana Accessions

    Science.gov (United States)

    Silva-Guzman, Macarena; Addo-Quaye, Charles; Dilkes, Brian P.

    2016-01-01

    Santa Clara, Limeport, and Berkeley are Arabidopsis thaliana accessions previously identified as diversely metal resistant. Yet these same accessions were determined to be genetically indistinguishable from the metal sensitive Col-0. We robustly tested tolerance for Zn, Ni and Cu, and genetic relatedness by growing these accessions under a range of Ni, Zn and Cu concentrations for three durations in multiple replicates. Neither metal resistance nor variance in growth were detected between them and Col-0. We re-sequenced the genomes of these accessions and all stocks available for each accession. In all cases they were nearly indistinguishable from the standard laboratory accession Col-0. As Santa Clara was allegedly collected from the Jasper Ridge serpentine outcrop in California, USA we investigated the possibility of extant A. thaliana populations adapted to serpentine soils. Botanically vouchered Arabidopsis accessions in the Jepson database were overlaid with soil maps of California. This provided no evidence of A. thaliana collections from serpentine sites in California. Thus, our work demonstrates that the Santa Clara, Berkeley and Limeport accessions are not metal tolerant, not genetically distinct from Col-0, and that there are no known serpentine adapted populations or accessions of A. thaliana. PMID:27467746

  19. The Quantitative Basis of the Arabidopsis Innate Immune System to Endemic Pathogens Depends on Pathogen Genetics.

    Directory of Open Access Journals (Sweden)

    Jason A Corwin

    2016-02-01

    Full Text Available The most established model of the eukaryotic innate immune system is derived from examples of large effect monogenic quantitative resistance to pathogens. However, many host-pathogen interactions involve many genes of small to medium effect and exhibit quantitative resistance. We used the Arabidopsis-Botrytis pathosystem to explore the quantitative genetic architecture underlying host innate immune system in a population of Arabidopsis thaliana. By infecting a diverse panel of Arabidopsis accessions with four phenotypically and genotypically distinct isolates of the fungal necrotroph B. cinerea, we identified a total of 2,982 genes associated with quantitative resistance using lesion area and 3,354 genes associated with camalexin production as measures of the interaction. Most genes were associated with resistance to a specific Botrytis isolate, which demonstrates the influence of pathogen genetic variation in analyzing host quantitative resistance. While known resistance genes, such as receptor-like kinases (RLKs and nucleotide-binding site leucine-rich repeat proteins (NLRs, were found to be enriched among associated genes, they only account for a small fraction of the total genes associated with quantitative resistance. Using publically available co-expression data, we condensed the quantitative resistance associated genes into co-expressed gene networks. GO analysis of these networks implicated several biological processes commonly connected to disease resistance, including defense hormone signaling and ROS production, as well as novel processes, such as leaf development. Validation of single gene T-DNA knockouts in a Col-0 background demonstrate a high success rate (60% when accounting for differences in environmental and Botrytis genetic variation. This study shows that the genetic architecture underlying host innate immune system is extremely complex and is likely able to sense and respond to differential virulence among pathogen

  20. Arabidopsis seedling flood-inoculation technique: a rapid and reliable assay for studying plant-bacterial interactions

    Directory of Open Access Journals (Sweden)

    Uppalapati Srinivasa R

    2011-10-01

    Full Text Available Abstract Background The Arabidopsis thaliana-Pseudomonas syringae model pathosystem is one of the most widely used systems to understand the mechanisms of microbial pathogenesis and plant innate immunity. Several inoculation methods have been used to study plant-pathogen interactions in this model system. However, none of the methods reported to date are similar to those occurring in nature and amicable to large-scale mutant screens. Results In this study, we developed a rapid and reliable seedling flood-inoculation method based on young Arabidopsis seedlings grown on MS medium. This method has several advantages over conventional soil-grown plant inoculation assays, including a shorter growth and incubation period, ease of inoculation and handling, uniform infection and disease development, requires less growth chamber space and is suitable for high-throughput screens. In this study we demonstrated the efficacy of the Arabidopsis seedling assay to study 1 the virulence factors of P. syringae pv. tomato DC3000, including type III protein secretion system (TTSS and phytotoxin coronatine (COR; 2 the effector-triggered immunity; and 3 Arabidopsis mutants affected in salicylic acid (SA- and pathogen-associated molecular pattern (PAMPs-mediated pathways. Furthermore, we applied this technique to study nonhost resistance (NHR responses in Arabidopsis using nonhost pathogens, such as P. syringae pv. tabaci, pv. glycinea and pv. tomato T1, and confirmed the functional role of FLAGELLIN-SENSING 2 (FLS2 in NHR. Conclusions The Arabidopsis seedling flood-inoculation assay provides a rapid, efficient and economical method for studying Arabidopsis-Pseudomonas interactions with minimal growth chamber space and time. This assay could also provide an excellent system for investigating the virulence mechanisms of P. syringae. Using this method, we demonstrated that FLS2 plays a critical role in conferring NHR against nonhost pathovars of P. syringae, but not to

  1. Jasmonate Signal Pathway in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Xiao-Yi Shan; Zhi-Long Wang; Daoxin Xie

    2007-01-01

    Jasmonates (JAs), which include jasmonic acid and its cyclopentane derivatives are synthesized from the octadecanoid pathway and widely distributed throughout the plant kingdom. JAs modulate the expression of numerous genes and mediate responses to stress, wounding, insect attack, pathogen infection, and UV damage. They also affect a variety of processes in many plant developmental processes. The JA signal pathway involves two important events: the biosynthesis of JA and the transduction of JA signal. Several important Arabidopsis mutants in jasmonate signal pathway were described in this review.

  2. Selection of Arabidopsis mutants overexpressing genes driven by the promoter of an auxin-inducible glutathione S-transferase gene

    NARCIS (Netherlands)

    Kop, D.A.M. van der; Schuyer, M.; Pinas, J.E.; Zaal, B.J. van der; Hooykaas, P.J.J.

    1999-01-01

    Transgenic arabidopsis plants were isolated that contained a T-DNA construct in which the promoter of an auxin-inducible glutathione S-transferase (GST) gene from tobacco was fused to the kanamycin resistance (nptII) as well as to the β-glucuronidase (gusA) reporter gene. Subsequently, seeds were tr

  3. Colonization of Arabidopsis roots by Pseudomonas fluorescens primes the plant to produce higher levels of ethylene upon pathogen infection

    NARCIS (Netherlands)

    Hase, S.; Pelt, J.A. van; Loon, L.C. van; Pieterse, C.M.J.

    2003-01-01

    Plants develop an enhanced defensive capacity against a broad spectrum of plant pathogens after colonization of the roots by selected strains of non-pathogenic, fluorescent Pseudomonas spp. In Arabidopsis thaliana, this rhizobacteria-induced systemic resistance (ISR) functions independently of salic

  4. Reference: 572 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available et al. 2007 May. Plant J. 50(3):439-51. Although glycine-rich RNA-binding protein 2 (GRP2) has been implicated in plant re...sponses to environmental stresses, the function and importance of GRP2 in stress responses are largely unknown. Here...haliana under high-salinity, cold or osmotic stress. GRP2 affects seed germination of Arabidopsis plants under salt stre...ss, but does not influence seed germination and seedling growth of Arabidopsis plants under osmotic stre...ss. GRP2 accelerates seed germination and seedling growth in Arabidopsis plants under cold stre

  5. Reference: 446 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available rk E et al. 2006 Nov. Plant Physiol. 142(3):1004-13. Arabidopsis (Arabidopsis thaliana) QUARTET (QRT) genes are require...d for pollen separation during normal floral development. In qrt mutants, the four products of microsporogenesis re...main fused and pollen grains are released as tetrads. In Arabid...opsis, tetrad analysis in qrt mutants has been used to map all five centromeres, easily distinguish sporophy...tic from gametophytic mutations, and accurately assess crossover interference. Using a combination of forward and re

  6. AtPIN: Arabidopsis thaliana Protein Interaction Network

    Directory of Open Access Journals (Sweden)

    Silva-Filho Marcio C

    2009-12-01

    Full Text Available Abstract Background Protein-protein interactions (PPIs constitute one of the most crucial conditions to sustain life in living organisms. To study PPI in Arabidopsis thaliana we have developed AtPIN, a database and web interface for searching and building interaction networks based on publicly available protein-protein interaction datasets. Description All interactions were divided into experimentally demonstrated or predicted. The PPIs in the AtPIN database present a cellular compartment classification (C3 which divides the PPI into 4 classes according to its interaction evidence and subcellular localization. It has been shown in the literature that a pair of genuine interacting proteins are generally expected to have a common cellular role and proteins that have common interaction partners have a high chance of sharing a common function. In AtPIN, due to its integrative profile, the reliability index for a reported PPI can be postulated in terms of the proportion of interaction partners that two proteins have in common. For this, we implement the Functional Similarity Weight (FSW calculation for all first level interactions present in AtPIN database. In order to identify target proteins of cytosolic glutamyl-tRNA synthetase (Cyt-gluRS (AT5G26710 we combined two approaches, AtPIN search and yeast two-hybrid screening. Interestingly, the proteins glutamine synthetase (AT5G35630, a disease resistance protein (AT3G50950 and a zinc finger protein (AT5G24930, which has been predicted as target proteins for Cyt-gluRS by AtPIN, were also detected in the experimental screening. Conclusions AtPIN is a friendly and easy-to-use tool that aggregates information on Arabidopsis thaliana PPIs, ontology, and sub-cellular localization, and might be a useful and reliable strategy to map protein-protein interactions in Arabidopsis. AtPIN can be accessed at http://bioinfo.esalq.usp.br/atpin.

  7. The Arabidopsis NIMIN proteins affect NPR1 differentially

    Directory of Open Access Journals (Sweden)

    Meike eHermann

    2013-04-01

    Full Text Available NON-EXPRESSOR OF PATHOGENESIS-RELATED GENES1 (NPR1 is the central regulator of the pathogen defense reaction systemic acquired resistance (SAR. NPR1 acts by sensing the SAR signal molecule salicylic acid (SA to induce expression of PATHOGENESIS-RELATED (PR genes. Mechanistically, NPR1 is the core of a transcription complex interacting with TGA transcription factors and NIM1 INTERACTING (NIMIN proteins. Arabidopsis NIMIN1 has been shown to suppress NPR1 activity in transgenic plants. The Arabidopsis NIMIN family comprises four structurally related, yet distinct members. Here, we show that NIMIN1, NIMIN2 and NIMIN3 are expressed differentially, and that the encoded proteins affect expression of the SAR marker PR-1 differentially. NIMIN3 is expressed constitutively at a low level, but NIMIN2 and NIMIN1 are both responsive to SA. While NIMIN2 is an immediate early SA-induced and NPR1-independent gene, NIMIN1 is activated after NIMIN2, but clearly before PR-1. Notably, NIMIN1, like PR-1, depends on NPR1. In a transient assay system, NIMIN3 suppresses SA-induced PR-1 expression, albeit to a lesser extent than NIMIN1, whereas NIMIN2 does not negatively affect PR-1 gene activation. Furthermore, although binding to the same domain in the C-terminus, NIMIN1 and NIMIN2 interact differentially with NPR1, thus providing a molecular basis for their opposing effects on NPR1. Together, our data suggest that the Arabidopsis NIMIN proteins are regulators of the SAR response. We propose that NIMINs act in a strictly consecutive and SA-regulated manner on the SA sensor protein NPR1, enabling NPR1 to monitor progressing threat by pathogens and to promote appropriate defense gene activation at distinct stages of SAR. In this scenario, the defense gene PR-1 is repressed at the onset of SAR by SA-induced, yet instable NIMIN1.

  8. Arabidopsis CDS blastp result: AK065259 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK065259 J013002J18 At5g16910.1 cellulose synthase family protein similar to gi:2827143 cellulose... synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 0.0 ...

  9. Arabidopsis CDS blastp result: AK102134 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK102134 J033085F12 At5g16910.1 cellulose synthase family protein similar to gi:2827143 cellulose... synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 0.0 ...

  10. Arabidopsis CDS blastp result: AK066835 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK066835 J013087I16 At5g16910.1 cellulose synthase family protein similar to gi:2827143 cellulose... synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 1e-171 ...

  11. Arabidopsis CDS blastp result: AK100523 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK100523 J023100P04 At5g16910.1 cellulose synthase family protein similar to gi:2827143 cellulose... synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 0.0 ...

  12. Arabidopsis CDS blastp result: AK102695 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK102695 J033103F21 At5g16910.1 cellulose synthase family protein similar to gi:2827143 cellulose... synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 0.0 ...

  13. Reference: 488 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available Inactivation of ATAB2 strongly affects Arabidopsis development and thylakoid mem...n center subunits is decreased and the association of their mRNAs with polysomes is affected. ATAB2 is a chl

  14. Reference: 212 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available identified in pea (Pisum sativum) using biochemical approaches. The Arabidopsis (...C75-IV, which we studied using a range of molecular, genetic, and biochemical techniques. Expression of atTO

  15. Reference: 480 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available activity was analyzed. Compared to all other Suc transporters, AtSUC9 had an ult...abidopsis (Arabidopsis thaliana) L. Heynh., was expressed in Xenopus (Xenopus laevis) oocytes, and transport

  16. Reference: 507 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available een them. However, little is known about the mechanisms that regulate the two pathways and the metabolic cro...ss-talk. To identify such regulatory mechanisms, we isolated and characterized the Arabidopsis T-DNA inserti

  17. Reference: 278 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available functional ERA1 gene, which encodes the beta-subunit of protein farnesyltransferase (PFT), exhibit pleiotropic effects...gnaling and meristem development. Here, we report the effects of T-DNA insertion mutations in the Arabidopsi

  18. Reference: 185 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available organisms, we suggest that AtARP4 is likely to exert its effects on plant develop...nuclear actin-related protein AtARP4 in Arabidopsis has multiple effects on plant development, including ear

  19. Arabidopsis CDS blastp result: AK069960 [KOME

    Lifescience Database Archive (English)

    Full Text Available thyltransferase 1 / caffeic acid/5-hydroxyferulic acid O-methyltransferase (OMT1) identical to O-methyltrans...T1) (Flavonol 3- O-methyltransferase 1) (Caffeic acid/5-hydroxyferulic acid O- methyltransferase) {Arabidopsis thaliana} 5e-60 ...

  20. Arabidopsis CDS blastp result: AK064768 [KOME

    Lifescience Database Archive (English)

    Full Text Available thyltransferase 1 / caffeic acid/5-hydroxyferulic acid O-methyltransferase (OMT1) identical to O-methyltrans...T1) (Flavonol 3- O-methyltransferase 1) (Caffeic acid/5-hydroxyferulic acid O- methyltransferase) {Arabidopsis thaliana} 1e-112 ...

  1. Arabidopsis CDS blastp result: AK061551 [KOME

    Lifescience Database Archive (English)

    Full Text Available ethyltransferase 1 / caffeic acid/5-hydroxyferulic acid O-methyltransferase (OMT1) identical to O-methyltran...MT1) (Flavonol 3- O-methyltransferase 1) (Caffeic acid/5-hydroxyferulic acid O- methyltransferase) {Arabidopsis thaliana} 2e-67 ...

  2. Arabidopsis CDS blastp result: AK104764 [KOME

    Lifescience Database Archive (English)

    Full Text Available ethyltransferase 1 / caffeic acid/5-hydroxyferulic acid O-methyltransferase (OMT1) identical to O-methyltran...MT1) (Flavonol 3- O-methyltransferase 1) (Caffeic acid/5-hydroxyferulic acid O- methyltransferase) {Arabidopsis thaliana} 2e-67 ...

  3. Arabidopsis CDS blastp result: AK098998 [KOME

    Lifescience Database Archive (English)

    Full Text Available thyltransferase 1 / caffeic acid/5-hydroxyferulic acid O-methyltransferase (OMT1) identical to O-methyltrans...T1) (Flavonol 3- O-methyltransferase 1) (Caffeic acid/5-hydroxyferulic acid O- methyltransferase) {Arabidopsis thaliana} 8e-57 ...

  4. Arabidopsis CDS blastp result: AK061859 [KOME

    Lifescience Database Archive (English)

    Full Text Available ethyltransferase 1 / caffeic acid/5-hydroxyferulic acid O-methyltransferase (OMT1) identical to O-methyltran...MT1) (Flavonol 3- O-methyltransferase 1) (Caffeic acid/5-hydroxyferulic acid O- methyltransferase) {Arabidopsis thaliana} 1e-100 ...

  5. Arabidopsis CDS blastp result: AK103387 [KOME

    Lifescience Database Archive (English)

    Full Text Available ntical to SC35-like splicing factor SCL28, 28 kD [Arabidopsis thaliana] GI:9843655; contains Pfam profile PF00076: RNA recognition motif. (a.k.a. RRM, RBD, or RNP domain) 2e-34 ...

  6. Reference: 564 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available 39-44 17360695 2007 Feb Proceedings of the National Academy of Sciences of the Un...tion in plants. Arabidopsis plasma membrane protein crucial for Ca2+ influx and touch sensing in roots. 9 36

  7. Reference: 796 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available ceedings of the National Academy of Sciences of the United States of America DeBolt...required for normal microtubule dynamics and organization in Arabidopsis. 46 18064-9 19004800 2008 Nov Pro

  8. Reference: 67 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available A complete knockout of AGD2 renders embryos inviable. We suggest that AGD2 synthesizes an important amino a...no acid-derived molecule important for activating defense signaling. Divergent roles in Arabidopsis thaliana

  9. Reference: 420 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available are found in various compartments in plant cells. The cytosolic and chloroplast APXs appear to play important...d development, suggesting that APX3 may not be an important antioxidant enzyme in Arabidopsis, at least unde

  10. Reference: 771 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available RCADIAN TIMEKEEPER (XCT), an Arabidopsis thaliana gene important for light regula...l elongation in xct is hyposensitive to red light but hypersensitive to blue light. Finally, XCT is important

  11. Reference: 797 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available that the level of GMPase activity regulates Arabidopsis sensitivity to NH(4)(+). Further analysis showed that defective N-glycosylati...on of proteins, unfolded protein response, and cell death in the roots are likely i

  12. Arabidopsis CDS blastp result: AK241712 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241712 J065197H24 At4g37750.1 68417.m05344 ovule development protein aintegumenta... (ANT) identical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 6e-27 ...

  13. Arabidopsis CDS blastp result: AK242957 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242957 J090089I15 At4g37750.1 68417.m05344 ovule development protein aintegumenta... (ANT) identical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 1e-28 ...

  14. Arabidopsis CDS blastp result: AK287726 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK287726 J065138E17 At4g37750.1 68417.m05344 ovule development protein aintegumenta... (ANT) identical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 1e-88 ...

  15. Arabidopsis CDS blastp result: AK242387 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242387 J080051E14 At4g37750.1 68417.m05344 ovule development protein aintegumenta... (ANT) identical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 2e-45 ...

  16. Arabidopsis CDS blastp result: AK106306 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK106306 002-101-C10 At4g37750.1 ovule development protein aintegumenta (ANT) ident...ical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 3e-89 ...

  17. Arabidopsis CDS blastp result: AK241272 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241272 J065132I19 At4g37750.1 68417.m05344 ovule development protein aintegumenta... (ANT) identical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 1e-88 ...

  18. Arabidopsis CDS blastp result: AK240892 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK240892 J065030K10 At4g37750.1 68417.m05344 ovule development protein aintegumenta... (ANT) identical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 5e-88 ...

  19. Arabidopsis CDS blastp result: AK109848 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK109848 002-148-F05 At4g37750.1 ovule development protein aintegumenta (ANT) ident...ical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 5e-73 ...

  20. Arabidopsis CDS blastp result: AK287673 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK287673 J065121E18 At4g37750.1 68417.m05344 ovule development protein aintegumenta... (ANT) identical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 6e-17 ...

  1. Arabidopsis CDS blastp result: AK287621 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK287621 J065066I09 At4g37750.1 68417.m05344 ovule development protein aintegumenta... (ANT) identical to ovule development protein aintegumenta (ANT) (GI:1244708) ) [Arabidopsis thaliana] 5e-85 ...

  2. Reference: 142 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available te S-glucosyltransferase, UGT74B1, to determine its role in the Arabidopsis glucosinolate pathway. Biochem...ical analyses demonstrate that recombinant UGT74B1 specifically glucosylates the th

  3. Reference: 522 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available tol phosphate (InsP) and phosphoinositide phosphate (PtdInsP) substrates. Arabidopsis thaliana has 15 genes encoding 5PTases. Biochem...ical analyses of a subgroup of 5PTase enzymes suggest th

  4. Reference: 459 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available plants. These results suggest an additive contribution of AMT1;1 and AMT1;3 to the overall ammonium uptake ...capacity in Arabidopsis roots under nitrogen-deficiency conditions. Additive contribution

  5. Arabidopsis CDS blastp result: AK288065 [KOME

    Lifescience Database Archive (English)

    Full Text Available al to sulfate tansporter Sultr1;3 [Arabidopsis thaliana] GI:10716805; contains Pfam profile PF00916: Sulfate... transporter family; contains Pfam profile PF01740: STAS domain; contains TIGRfam profile TIGR00815: sulfate permease 1e-145 ...

  6. Reference: 645 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available rter AtDUR3 in nitrogen nutrition in Arabidopsis. In transgenic lines expressing ... impaired growth on urea as a sole nitrogen source were used to investigate a role of the H+/urea co-transpo

  7. The fifth international conference on Arabidopsis research

    Energy Technology Data Exchange (ETDEWEB)

    Hangarter, R.; Scholl, R.; Davis, K.; Feldmann, K.

    1993-12-31

    This volume contains abstracts of oral and poster presentations made in conjunction with the Fifth International Conference on Arabidopsis Research held August 19--22, 1993 at the Ohio State University, Columbus, Ohio.

  8. Reference: 711 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available of the RLK signaling pathway, which also mediates adaptation to Na(+) stress. RLK pathway components, known... The Arabidopsis kinase-associated protein phosphatase regulates adaptation to Na+ stress. 2 612-22 18162596

  9. Reference: 734 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available umi et al. 2008 Apr. Development 135(7):1335-45. CAPRICE (CPC) encodes a small protein with an R3 MYB motif ...doreduplication. Arabidopsis CAPRICE-LIKE MYB 3 (CPL3) controls endoreduplication and flowering development

  10. Arabidopsis CDS blastp result: AK101526 [KOME

    Lifescience Database Archive (English)

    Full Text Available ucosaminyltransferase, putative similar to N-acetylglucosaminyltransferase I from Arabidopsis thaliana [gi:5139335]; contains AT-AC non-consensus splice sites at intron 13 1e-179 ...

  11. Reference: 733 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available role in this transition. Specifically, two autonomous factors in the Arabidopsis...tes FCA alternative polyadenylation and promotes flowering as a novel factor in the autonomous pathway. Firs

  12. Reference: 343 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available the characterization of a T-DNA insertion mutant of the Arabidopsis CAP-C gene. Analysis of the progeny of selfe...matin was observed between segregating mitotic chromosomes in pollen produced by selfed heterozygotes. Addit

  13. Arabidopsis CDS blastp result: AK241281 [KOME

    Lifescience Database Archive (English)

    Full Text Available 2 protein) [Arabidopsis thaliana]; a false single bp exon was added to circumvent a single basepair insertion in the genomic sequence, supported by cDNA/genome alignment. 3e-19 ...

  14. Arabidopsis CDS blastp result: AK241243 [KOME

    Lifescience Database Archive (English)

    Full Text Available 2 protein) [Arabidopsis thaliana]; a false single bp exon was added to circumvent a single basepair insertion in the genomic sequence, supported by cDNA/genome alignment. 6e-11 ...

  15. Arabidopsis CDS blastp result: AK243188 [KOME

    Lifescience Database Archive (English)

    Full Text Available 2 protein) [Arabidopsis thaliana]; a false single bp exon was added to circumvent a single basepair insertion in the genomic sequence, supported by cDNA/genome alignment. 8e-23 ...

  16. Arabidopsis CDS blastp result: AK242986 [KOME

    Lifescience Database Archive (English)

    Full Text Available 2 protein) [Arabidopsis thaliana]; a false single bp exon was added to circumvent a single basepair insertion in the genomic sequence, supported by cDNA/genome alignment. 1e-17 ...

  17. Reference: 30 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available ponse to various biotic and abiotic stresses. However the physiological role of t...his pathway remains obscure. To elucidate its role in plants, we analyzed Arabidopsis T-DNA knockout mutants

  18. Arabidopsis CDS blastp result: AK062082 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK062082 001-044-F11 At3g59970.3 methylenetetrahydrofolate reductase 1 (MTHFR1) ide...ntical to methylenetetrahydrofolate reductase MTHFR1 [Arabidopsis thaliana] GI:5911425 4e-81 ...

  19. Reference: 783 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available sis ACBP6 was confirmed by analyses of transgenic Arabidopsis expressing autofluorescence-tagged ACBP6 and w... mRNA encoding phospholipase Ddelta. Lipid profiling analyses of rosettes from co

  20. Reference: 789 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available ylakoid membranes. Microarray analysis of the chl27-t mutant showed repression of numerous nuclear genes involved in photosynthesis...d CHL27 proteins. Role of Arabidopsis CHL27 protein for photosynthesis, chloroplast development and gene exp

  1. Reference: 352 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available em II and has a specific function distinct from 2-Cys peroxiredoxin in protecting photosynthesis. Its absenc...f Arabidopsis thaliana is attached to the thylakoids and functions in context of photosynthesis

  2. Reference: 21 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available ication of a number of mutant lines with altered Chl fluorescence characteristics. Analysis of photosynthesis...cation of mutants of Arabidopsis defective in acclimation of photosynthesis to th

  3. Reference: 413 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available ollination and fertilization, and, in the absence of fertilization, flowers senesce. In the Arabidopsis thal...ARF8 acts as an inhibitor to stop further carpel development in the absence of fertilization and the generat

  4. Reference: 405 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available as previously thought. These mutants will prove to be valuable resources for understanding laccase functions in vivo. Mutant identifi...cation and characterization of the laccase gene family in Arabidopsis. 11 2563-9 16

  5. Reference: 263 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available idopsis leaves GLB1 expression and PII protein levels were not significantly affected by either the day/nigh...bolism. Physiological characterisation of Arabidopsis mutants affected in the expression of the putative reg

  6. Reference: 160 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available excessive accumulation of these toxic compounds impairs cell death containment and counteracts the effect...iveness of the plant defenses to restrict pathogen infection. Arabidopsis SHMT1, a

  7. Arabidopsis CDS blastp result: AK242550 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242550 J080319D10 At2g35630.1 68415.m04369 microtubule organization 1 protein (MO...R1) identical to microtubule organization 1 protein GI:14317953 from [Arabidopsis thaliana] 5e-44 ...

  8. Reference: 301 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available n phosphatidylinositol metabolism and is encoded by an At5PTase gene family in Arabidopsis thaliana. A previous study...ntracellular calcium levels. In this study, we provide evidence that At5PTase13 m

  9. Reference: 289 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available f flavonoids in Arabidopsis seed coat. 11 2966-80 16243908 2005 Nov The Plant cell Caboche Michel|Debeaujon Isabelle|Kerhoas Lucien|Lepiniec Loïc|Pourcel Lucille|Routaboul Jean-Marc

  10. Reference: 684 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available cellular proliferation and expansion at nanomolar concentrations. PSY1 is widely expressed in various Arabi...ulfated glycopeptide involved in cellular proliferation and expansion in Arabidopsis. 46 18333-8 17989228 20

  11. Reference: 147 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available the region-specific control of trichome development of Arabidopsis. 3 389-98 15604688 2004 May Plant molecular biology Hulskamp Mart...in|Kirik Victor|Schiefelbein John|Simon Marissa|Wester Katja

  12. Arabidopsis CDS blastp result: AK241043 [KOME

    Lifescience Database Archive (English)

    Full Text Available upted by a stop codon, creating non-consensus donor and acceptor splice sites. 2e-41 ... ...tical to SP|P92997 Germin-like protein subfamily 1 member 13 precursor {Arabidopsis thaliana}; exon 2 interr

  13. Arabidopsis CDS blastp result: AK243135 [KOME

    Lifescience Database Archive (English)

    Full Text Available upted by a stop codon, creating non-consensus donor and acceptor splice sites. 7e-43 ... ...tical to SP|P92997 Germin-like protein subfamily 1 member 13 precursor {Arabidopsis thaliana}; exon 2 interr

  14. Reference: 798 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available iption factors, control the delicately tuned reorientation and timing of cell div...EZ and SOMBRERO control the orientation of cell division plane in Arabidopsis root stem cells. 6 913-22 1908

  15. Potential use of a serpin from Arabidopsis for pest control.

    Directory of Open Access Journals (Sweden)

    Fernando Alvarez-Alfageme

    Full Text Available Although genetically modified (GM plants expressing toxins from Bacillus thuringiensis (Bt protect agricultural crops against lepidopteran and coleopteran pests, field-evolved resistance to Bt toxins has been reported for populations of several lepidopteran species. Moreover, some important agricultural pests, like phloem-feeding insects, are not susceptible to Bt crops. Complementary pest control strategies are therefore necessary to assure that the benefits provided by those insect-resistant transgenic plants are not compromised and to target those pests that are not susceptible. Experimental GM plants producing plant protease inhibitors have been shown to confer resistance against a wide range of agricultural pests. In this study we assessed the potential of AtSerpin1, a serpin from Arabidopsis thaliana (L. Heynh., for pest control. In vitro assays were conducted with a wide range of pests that rely mainly on either serine or cysteine proteases for digestion and also with three non-target organisms occurring in agricultural crops. AtSerpin1 inhibited proteases from all pest and non-target species assayed. Subsequently, the cotton leafworm Spodoptera littoralis Boisduval and the pea aphid Acyrthosiphon pisum (Harris were fed on artificial diets containing AtSerpin1, and S. littoralis was also fed on transgenic Arabidopsis plants overproducing AtSerpin1. AtSerpin1 supplied in the artificial diet or by transgenic plants reduced the growth of S. littoralis larvae by 65% and 38%, respectively, relative to controls. Nymphs of A. pisum exposed to diets containing AtSerpin1 suffered high mortality levels (LC(50 = 637 µg ml(-1. The results indicate that AtSerpin1 is a good candidate for exploitation in pest control.

  16. Functional analysis of the theobroma cacao NPR1 gene in arabidopsis

    Directory of Open Access Journals (Sweden)

    Verica Joseph

    2010-11-01

    Full Text Available Abstract Background The Arabidopsis thaliana NPR1 gene encodes a transcription coactivator (NPR1 that plays a major role in the mechanisms regulating plant defense response. After pathogen infection and in response to salicylic acid (SA accumulation, NPR1 translocates from the cytoplasm into the nucleus where it interacts with other transcription factors resulting in increased expression of over 2000 plant defense genes contributing to a pathogen resistance response. Results A putative Theobroma cacao NPR1 cDNA was isolated by RT-PCR using degenerate primers based on homologous sequences from Brassica, Arabidopsis and Carica papaya. The cDNA was used to isolate a genomic clone from Theobroma cacao containing a putative TcNPR1 gene. DNA sequencing revealed the presence of a 4.5 kb coding region containing three introns and encoding a polypeptide of 591 amino acids. The predicted TcNPR1 protein shares 55% identity and 78% similarity to Arabidopsis NPR1, and contains each of the highly conserved functional domains indicative of this class of transcription factors (BTB/POZ and ankyrin repeat protein-protein interaction domains and a nuclear localization sequence (NLS. To functionally define the TcNPR1 gene, we transferred TcNPR1 into an Arabidopsis npr1 mutant that is highly susceptible to infection by the plant pathogen Pseudomonas syringae pv. tomato DC3000. Driven by the constitutive CaMV35S promoter, the cacao TcNPR1 gene partially complemented the npr1 mutation in transgenic Arabidopsis plants, resulting in 100 fold less bacterial growth in a leaf infection assay. Upon induction with SA, TcNPR1 was shown to translocate into the nucleus of leaf and root cells in a manner identical to Arabidopsis NPR1. Cacao NPR1 was also capable of participating in SA-JA signaling crosstalk, as evidenced by the suppression of JA responsive gene expression in TcNPR1 overexpressing transgenic plants. Conclusion Our data indicate that the TcNPR1 is a functional

  17. Arabidopsis CDS blastp result: AK071710 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK071710 J023110L07 At4g14030.1 selenium-binding protein, putative contains Pfam profile PF05694: 56kDa sele...nium binding protein (SBP56); identical to Putative selenium-binding protein (Swiss...-Prot:O23264) [Arabidopsis thaliana]; similar to selenium binding protein (GI:15485232) [Arabidopsis thalian...a]; identical to cDNA from partial mRNA for selenium binding protein (sbp gene) GI:15485231 1e-162 ...

  18. Reference: 221 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available ell cycle. In addition, RAD51 is required for meiosis and its Arabidopsis (Arabidopsis thaliana) ortholog is important... cell cultures, the RAD51 paralog RAD51C is also important for mitotic homologous...ortant for recombination and DNA repair in the mitotic c...chromosome (homolog) pairing, synapsis, and recombination. The budding yeast (Saccharomyces cerevisiae) RAD51 gene is known to be imp

  19. Reference: 598 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available omoter is markedly reduced in the cdkc;2 and cyct1;5 mutants, indicating that the kinase complexes are important... flowering. These results establish Arabidopsis CDKC kinase complexes as important...T1;4 and CYCT1;5, play important roles in infection with Cauliflower mosaic virus...hat Arabidopsis thaliana CDK9-like proteins, CDKC;1 and CDKC;2, and their interacting cyclin T partners, CYC

  20. Physiological and Molecular Features of the Pathosystem Arabidopsis thaliana L.-Sclerotinia sclerotiorum Libert

    Institute of Scientific and Technical Information of China (English)

    Fu-Ming Dai; Tong Xu; Gerhard A. Wolf; Zu-Hua He

    2006-01-01

    The fungal pathogen Sclerotinia sclerotiorum Libert causes rot diseases on many crops worldwide and large economic losses occur frequently because of a lack of resistant varieties. The pathogenesis of S. sclerotiorum and the molecular basis of plant responses to the pathogen are poorly understood. In the present investigation,the process of S. sclerotiorum infection in Arabidopsis thaliana L., a plant that is highly susceptible to this fungus, was analysed. In addition, the defense activation in the host was investigated. A convenient inoculation method using millet grain was developed for S. sclerotiorum in Arabidopsis. The fungus rapidly infected the plants, probably through ball- or cushion-like infection structures. Visible symptoms developed within 24h and plants were killed 72 h after inoculation. Cellulase, the main enzyme that caused host tissues to rot,was secreted by S. sclerotiorum in a pH-dependent manner. Oxalic acid, another pathogenic factor secreted by the fungus, induced necrotic lesions on the leaves. Infection with S. sclerotiorum strongly induced the production of the pathogenesis-related (PR) proteins β-1,3-glucanase and chitinase in Arabidopsis.Furthermore, the PR gene PDF. 1 was induced, but not PR1, indicating that the pathogen activated basal defense of jasmonic acid/ethylene dependence, which is consistent with its necrotrophic characteristics.This pathosystem for Arabidopsis-S. sclerotiorum could provide an approach for the analysis of the interactions between S. sclerotiorum and other crops, thereby facilitating genetic manipulation techniques for controlling this pathogen.

  1. Overexpression of Nelumbo nucifera metallothioneins 2a and 3 enhances seed germination vigor in Arabidopsis.

    Science.gov (United States)

    Zhou, Yuliang; Chu, Pu; Chen, Huhui; Li, Yin; Liu, Jun; Ding, Yu; Tsang, Edward W T; Jiang, Liwen; Wu, Keqiang; Huang, Shangzhi

    2012-03-01

    Metallothioneins (MTs) are small, cysteine-rich and metal-binding proteins which are involved in metal homeostasis and scavenging of reactive oxygen species. Although plant MTs have been intensively studied, their roles in seeds remain to be clearly established. Here, we report the isolation and characterization of NnMT2a, NnMT2b and NnMT3 from sacred lotus (Nelumbo nucifera Gaertn.) and their roles in seed germination vigor. The transcripts of NnMT2a, NnMT2b and NnMT3 were highly expressed in developing and germinating sacred lotus seeds, and were dramatically up-regulated in response to high salinity, oxidative stresses and heavy metals. Analysis of transformed Arabidopsis protoplasts showed that NnMT2a-YFP and NnMT3-YFP were localized in cytoplasm and nucleoplasm. Transgenic Arabidopsis seeds overexpressing NnMT2a and NnMT3 displayed improved resistance to accelerated aging (AA) treatment, indicating their significant roles in seed germination vigor. These transgenic seeds also exhibited higher superoxide dismutase activity compared to wild-type seeds after AA treatment. In addition, we showed that NnMT2a and NnMT3 conferred improved germination ability to NaCl and methyl viologen on transgenic Arabidopsis seeds. Taken together, these data demonstrate that overexpression of NnMT2a and NnMT3 in Arabidopsis significantly enhances seed germination vigor after AA treatment and under abiotic stresses.

  2. Biochemical and structural properties of cyanases from Arabidopsis thaliana and Oryza sativa.

    Science.gov (United States)

    Qian, Dan; Jiang, Lin; Lu, Lu; Wei, Chunhong; Li, Yi

    2011-01-01

    Cyanate is toxic to all organisms. Cyanase converts cyanate to CO₂ and NH₃ in a bicarbonate-dependent reaction. The biophysical functions and biochemical characteristics of plant cyanases are poorly studied, although it has been investigated in a variety of proteobacteria, cyanobacteria and fungi. In this study, we characterised plant cyanases from Arabidopsis thaliana and Oryza sativa (AtCYN and OsCYN). Prokaryotic-expressed AtCYN and OsCYN both showed cyanase activity in vitro. Temperature had a similar influence on the activity of both cyanases, but pH had a differential impact on AtCYN and OsCYN activity. Homology modelling provided models of monomers of AtCYN and OsCYN, and a coimmunoprecipitation assay and gel filtration indicated that AtCYN and OsCYN formed homodecamers. The analysis of single-residue mutants of AtCYN indicated that the conserved catalytic residues also contributed to the stability of the homodecamer. KCNO treatment inhibited Arabidopsis germination and early seedling growth. Plants containing AtCYN or OsCYN exhibited resistance to KCNO stress, which demonstrated that one role of cyanases in plants is detoxification. Transcription level of AtCYN was higher in the flower than in other organs of Arabidopsis. AtCYN transcription was not significantly affected by KCNO treatment in Arabidopsis, but was induced by salt stress. This research broadens our knowledge on plant detoxification of cyanate via cyanase.

  3. Biochemical and structural properties of cyanases from Arabidopsis thaliana and Oryza sativa.

    Directory of Open Access Journals (Sweden)

    Dan Qian

    Full Text Available Cyanate is toxic to all organisms. Cyanase converts cyanate to CO₂ and NH₃ in a bicarbonate-dependent reaction. The biophysical functions and biochemical characteristics of plant cyanases are poorly studied, although it has been investigated in a variety of proteobacteria, cyanobacteria and fungi. In this study, we characterised plant cyanases from Arabidopsis thaliana and Oryza sativa (AtCYN and OsCYN. Prokaryotic-expressed AtCYN and OsCYN both showed cyanase activity in vitro. Temperature had a similar influence on the activity of both cyanases, but pH had a differential impact on AtCYN and OsCYN activity. Homology modelling provided models of monomers of AtCYN and OsCYN, and a coimmunoprecipitation assay and gel filtration indicated that AtCYN and OsCYN formed homodecamers. The analysis of single-residue mutants of AtCYN indicated that the conserved catalytic residues also contributed to the stability of the homodecamer. KCNO treatment inhibited Arabidopsis germination and early seedling growth. Plants containing AtCYN or OsCYN exhibited resistance to KCNO stress, which demonstrated that one role of cyanases in plants is detoxification. Transcription level of AtCYN was higher in the flower than in other organs of Arabidopsis. AtCYN transcription was not significantly affected by KCNO treatment in Arabidopsis, but was induced by salt stress. This research broadens our knowledge on plant detoxification of cyanate via cyanase.

  4. HAL1 mediate salt adaptation in Arabidopsis thaliana

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The yeast HAL1 gene was introduced into Arabidopsis thaliana by Agrobacterium tumefaciens-mediated transformation with vacuum infiltration under the control of CaMV 35S promoter.Thirty-three individual kanamycin resistant plants were obtained from 75,000 seeds.Southern blotting analysis indicated that HAL1 gene had been integrated into all of the transgenic plants' genomes.The copy number of HAL1 gene in transgenic plants was mostly 1 to 3 by Southern analysis.Phenotypes of transgenic plants have no differences with wild type plants.Several samples of transformants were self-pollinated,and progenies from transformed and non-transformed plants(controls)were evaluated for salt tolerance and gene expression.Measurement of concentrations of intracellular K+ and Na+ showed that transgenic lines were able to retain less Na+ than that of the control under salt stress.Results from different tests indicated the expression of HAL1 gene promotes a higher level of salt tolerance in vivo in the transgenic Arabidopsis plants.

  5. Novel disease susceptibility factors for fungal necrotrophic pathogens in Arabidopsis.

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    Albor Dobón

    2015-04-01

    Full Text Available Host cells use an intricate signaling system to respond to invasions by pathogenic microorganisms. Although several signaling components of disease resistance against necrotrophic fungal pathogens have been identified, our understanding for how molecular components and host processes contribute to plant disease susceptibility is rather sparse. Here, we identified four transcription factors (TFs from Arabidopsis that limit pathogen spread. Arabidopsis mutants defective in any of these TFs displayed increased disease susceptibility to Botrytis cinerea and Plectosphaerella cucumerina, and a general activation of non-immune host processes that contribute to plant disease susceptibility. Transcriptome analyses revealed that the mutants share a common transcriptional signature of 77 up-regulated genes. We characterized several of the up-regulated genes that encode peptides with a secretion signal, which we named PROVIR (for provirulence factors. Forward and reverse genetic analyses revealed that many of the PROVIRs are important for disease susceptibility of the host to fungal necrotrophs. The TFs and PROVIRs identified in our work thus represent novel genetic determinants for plant disease susceptibility to necrotrophic fungal pathogens.

  6. Melatonin induces the transcripts of CBF/DREB1s and their involvement in both abiotic and biotic stresses in Arabidopsis.

    Science.gov (United States)

    Shi, Haitao; Qian, Yongqiang; Tan, Dun-Xian; Reiter, Russel J; He, Chaozu

    2015-10-01

    Melatonin (N-acetyl-5-methoxytryptamine) is a naturally occurring small molecule that acts as an important secondary messenger in plant stress responses. However, the mechanism underlying the melatonin-mediated signaling pathway in plant stress responses has not been established. C-repeat-binding factors (CBFs)/Drought response element Binding 1 factors (DREB1s) encode transcription factors that play important roles in plant stress responses. This study has determined that endogenous melatonin and transcripts level of CBFs (AtCBF1, AtCBF2, and AtCBF3) in Arabidopsis leaves were significantly induced by salt, drought, and cold stresses and by pathogen Pseudomonas syringe pv. tomato (Pst) DC3000 infection. Moreover, both exogenous melatonin treatment and overexpression of CBFs conferred enhanced resistance to both abiotic and biotic stresses in Arabidopsis. Notably, AtCBFs and exogenous melatonin treatment positively regulated the mRNA expression of several stress-responsive genes (COR15A, RD22, and KIN1) and accumulation of soluble sugars content such as sucrose in Arabidopsis under control and stress conditions. Additionally, exogenous sucrose also conferred improved resistance to both abiotic and biotic stresses in Arabidopsis. Taken together, this study indicates that AtCBFs confer enhanced resistance to both abiotic and biotic stresses, and AtCBF-mediated signaling pathway and sugar accumulation may be involved in melatonin-mediated stress response in Arabidopsis, at least partially.

  7. Advances in Arabidopsis research in China from 2006 to 2007

    Institute of Scientific and Technical Information of China (English)

    LIANG Yan; ZUO JianRu; YANG WeiCai

    2007-01-01

    @@ Arabidopsis thaliana, a model plant species, has a number of advantages over other plant species as an experimental organism due to many of its genetic and genomic features. The Chinese Arabidopsis community has made significant contributions to plant biology research in recent years[1,2]. In 2006, studies of plant biology in China received more attention than ever before, especially those pertaining to Arabidopsis research. Here we briefly summarize recent advances in Arabidopsis research in China.

  8. The Combined Action of ENHANCED DISEASE SUSCEPTIBILITY1, PHYTOALEXIN DEFICIENT4, and SENESCENCE-ASSOCIATED101 Promotes Salicylic Acid-Mediated Defenses to Limit Fusarium graminearum Infection in Arabidopsis thaliana.

    Science.gov (United States)

    Makandar, Ragiba; Nalam, Vamsi J; Chowdhury, Zulkarnain; Sarowar, Sujon; Klossner, Guy; Lee, Hyeonju; Burdan, Dehlia; Trick, Harold N; Gobbato, Enrico; Parker, Jane E; Shah, Jyoti

    2015-08-01

    Fusarium graminearum causes Fusarium head blight (FHB) disease in wheat and other cereals. F. graminearum also causes disease in Arabidopsis thaliana. In both Arabidopsis and wheat, F. graminearum infection is limited by salicylic acid (SA) signaling. Here, we show that, in Arabidopsis, the defense regulator EDS1 (ENHANCED DISEASE SUSCEPTIBILITY1) and its interacting partners, PAD4 (PHYTOALEXIN-DEFICIENT4) and SAG101 (SENESCENCE-ASSOCIATED GENE101), promote SA accumulation to curtail F. graminearum infection. Characterization of plants expressing the PAD4 noninteracting eds1(L262P) indicated that interaction between EDS1 and PAD4 is critical for limiting F. graminearum infection. A conserved serine in the predicted acyl hydrolase catalytic triad of PAD4, which is not required for defense against bacterial and oomycete pathogens, is necessary for limiting F. graminearum infection. These results suggest a molecular configuration of PAD4 in Arabidopsis defense against F. graminearum that is different from its defense contribution against other pathogens. We further show that constitutive expression of Arabidopsis PAD4 can enhance FHB resistance in Arabidopsis and wheat. Taken together with previous studies of wheat and Arabidopsis expressing salicylate hydroxylase or the SA-response regulator NPR1 (NON-EXPRESSER OF PR GENES1), our results show that exploring fundamental processes in a model plant provides important leads to manipulating crops for improved disease resistance.

  9. A rapid and robust method of identifying transformed Arabidopsis thaliana seedlings following floral dip transformation

    Directory of Open Access Journals (Sweden)

    Gray John C

    2006-11-01

    Full Text Available Abstract Background The floral dip method of transformation by immersion of inflorescences in a suspension of Agrobacterium is the method of choice for Arabidopsis transformation. The presence of a marker, usually antibiotic- or herbicide-resistance, allows identification of transformed seedlings from untransformed seedlings. Seedling selection is a lengthy process which does not always lead to easily identifiable transformants. Selection for kanamycin-, phosphinothricin- and hygromycin B-resistance commonly takes 7–10 d and high seedling density and fungal contamination may result in failure to recover transformants. Results A method for identifying transformed seedlings in as little as 3.25 d has been developed. Arabidopsis T1 seeds obtained after floral dip transformation are plated on 1% agar containing MS medium and kanamycin, phosphinothricin or hygromycin B, as appropriate. After a 2-d stratification period, seeds are subjected to a regime of 4–6 h light, 48 h dark and 24 h light (3.25 d. Kanamycin-resistant and phosphinothricin-resistant seedlings are easily distinguished from non-resistant seedlings by green expanded cotyledons whereas non-resistant seedlings have pale unexpanded cotyledons. Seedlings grown on hygromycin B differ from those grown on kanamycin and phosphinothricin as both resistant and non-resistant seedlings are green. However, hygromycin B-resistant seedlings are easily identified as they have long hypocotyls (0.8–1.0 cm whereas non-resistant seedlings have short hypocotyls (0.2–0.4 cm. Conclusion The method presented here is an improvement on current selection methods as it allows quicker identification of transformed seedlings: transformed seedlings are easily discernable from non-transformants in as little as 3.25 d in comparison to the 7–10 d required for selection using current protocols.

  10. Enhancement of Thiamin Content in Arabidopsis thaliana by Metabolic Engineering.

    Science.gov (United States)

    Dong, Wei; Stockwell, Virginia O; Goyer, Aymeric

    2015-12-01

    Thiamin is an essential nutrient in the human diet. Severe thiamin deficiency leads to beriberi, a lethal disease which is common in developing countries. Thiamin biofortification of staple food crops is a possible strategy to alleviate thiamin deficiency-related diseases. In plants, thiamin plays a role in the response to abiotic and biotic stresses, and data from the literature suggest that boosting thiamin content could increase resistance to stresses. Here, we tested an engineering strategy to increase thiamin content in Arabidopsis. Thiamin is composed of a thiazole ring linked to a pyrimidine ring by a methylene bridge. THI1 and THIC are the first committed steps in the synthesis of the thiazole and pyrimidine moieties, respectively. Arabidopsis plants were transformed with a vector containing the THI1-coding sequence under the control of a constitutive promoter. Total thiamin leaf content in THI1 plants was up approximately 2-fold compared with the wild type. THI1-overexpressing lines were then crossed with pre-existing THIC-overexpressing lines. Resulting THI1 × THIC plants accumulated up to 3.4- and 2.6-fold more total thiamin than wild-type plants in leaf and seeds, respectively. After inoculation with Pseudomonas syringae, THI1 × THIC plants had lower populations than the wild-type control. However, THI1 × THIC plants subjected to various abiotic stresses did not show any visible or biochemical changes compared with the wild type. We discuss the impact of engineering thiamin biosynthesis on the nutritional value of plants and their resistance to biotic and abiotic stresses.

  11. Effector-Triggered Immune Response in Arabidopsis thaliana Is a Quantitative Trait.

    Science.gov (United States)

    Iakovidis, Michail; Teixeira, Paulo J P L; Exposito-Alonso, Moises; Cowper, Matthew G; Law, Theresa F; Liu, Qingli; Vu, Minh Chau; Dang, Troy Minh; Corwin, Jason A; Weigel, Detlef; Dangl, Jeffery L; Grant, Sarah R

    2016-09-01

    We identified loci responsible for natural variation in Arabidopsis thaliana (Arabidopsis) responses to a bacterial pathogen virulence factor, HopAM1. HopAM1 is a type III effector protein secreted by the virulent Pseudomonas syringae strain Pto DC3000. Delivery of HopAM1 from disarmed Pseudomonas strains leads to local cell death, meristem chlorosis, or both, with varying intensities in different Arabidopsis accessions. These phenotypes are not associated with differences in bacterial growth restriction. We treated the two phenotypes as quantitative traits to identify host loci controlling responses to HopAM1. Genome-wide association (GWA) of 64 Arabidopsis accessions identified independent variants highly correlated with response to each phenotype. Quantitative trait locus (QTL) mapping in a recombinant inbred population between Bur-0 and Col-0 accessions revealed genetic linkage to regions distinct from the top GWA hits. Two major QTL associated with HopAM1-induced cell death were also associated with HopAM1-induced chlorosis. HopAM1-induced changes in Arabidopsis gene expression showed that rapid HopAM1-dependent cell death in Bur-0 is correlated with effector-triggered immune responses. Studies of the effect of mutations in known plant immune system genes showed, surprisingly, that both cell death and chlorosis phenotypes are enhanced by loss of EDS1, a regulatory hub in the plant immune-signaling network. Our results reveal complex genetic architecture for response to this particular type III virulence effector, in contrast to the typical monogenic control of cell death and disease resistance triggered by most type III effectors.

  12. Effector-Triggered Immune Response in Arabidopsis thaliana Is a Quantitative Trait

    Science.gov (United States)

    Iakovidis, Michail; Teixeira, Paulo J. P. L.; Exposito-Alonso, Moises; Cowper, Matthew G.; Law, Theresa F.; Liu, Qingli; Vu, Minh Chau; Dang, Troy Minh; Corwin, Jason A.; Weigel, Detlef; Dangl, Jeffery L.; Grant, Sarah R.

    2016-01-01

    We identified loci responsible for natural variation in Arabidopsis thaliana (Arabidopsis) responses to a bacterial pathogen virulence factor, HopAM1. HopAM1 is a type III effector protein secreted by the virulent Pseudomonas syringae strain Pto DC3000. Delivery of HopAM1 from disarmed Pseudomonas strains leads to local cell death, meristem chlorosis, or both, with varying intensities in different Arabidopsis accessions. These phenotypes are not associated with differences in bacterial growth restriction. We treated the two phenotypes as quantitative traits to identify host loci controlling responses to HopAM1. Genome-wide association (GWA) of 64 Arabidopsis accessions identified independent variants highly correlated with response to each phenotype. Quantitative trait locus (QTL) mapping in a recombinant inbred population between Bur-0 and Col-0 accessions revealed genetic linkage to regions distinct from the top GWA hits. Two major QTL associated with HopAM1-induced cell death were also associated with HopAM1-induced chlorosis. HopAM1-induced changes in Arabidopsis gene expression showed that rapid HopAM1-dependent cell death in Bur-0 is correlated with effector-triggered immune responses. Studies of the effect of mutations in known plant immune system genes showed, surprisingly, that both cell death and chlorosis phenotypes are enhanced by loss of EDS1, a regulatory hub in the plant immune-signaling network. Our results reveal complex genetic architecture for response to this particular type III virulence effector, in contrast to the typical monogenic control of cell death and disease resistance triggered by most type III effectors. PMID:27412712

  13. The interaction of Arabidopsis with Piriformospora indica shifts from initial transient stress induced by fungus-released chemical mediators to a mutualistic interaction after physical contact of the two symbionts

    OpenAIRE

    Vahabi, K.; Sherameti, I.; Bakshi, M.; Mrozinska, A.; Ludwig, A.; M. Reichelt; Oelmüller, R

    2015-01-01

    Background Piriformospora indica, an endophytic fungus of Sebacinales, colonizes the roots of many plant species including Arabidopsis thaliana. The symbiotic interaction promotes plant performance, growth and resistance/tolerance against abiotic and biotic stress. Results We demonstrate that exudated compounds from the fungus activate stress and defense responses in the Arabidopsis roots and shoots before the two partners are in physical contact. They induce stomata closure, stimulate reacti...

  14. Green peach aphid infestation induces Arabidopsis PHYTOALEXIN-DEFICIENT4 expression at site of insect feeding.

    Science.gov (United States)

    Louis, Joe; Mondal, Hossain A; Shah, Jyoti

    2012-11-01

    The Arabidopsis thaliana PHYTOALEXIN-DEFICIENT4 (PAD4) protein, which has homology to lipases, is required for phloem-based resistance against the green peach aphid (GPA; Myzus persicae Sülzer). PAD4 modulates antibiotic and antixenotic defenses against GPA. PAD4 in conjunction with its interacting partner ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1) also functions in basal resistance to bacterial and oomycete pathogens by promoting salicylic acid (SA)-dependent and SA-independent defenses. By contrast, neither EDS1 nor SA is required for PAD4-controlled defense against GPA. Distinct molecular activities of PAD4 are involved in different aspects of Arabidopsis defense against GPA and pathogens. Histochemical analysis of plants containing a PAD4p:GUS chimera, which expresses the GUS reporter from the PAD4 promoter, indicated strong PAD4 promoter activity at the site of penetration of the vasculature by the insect stylet. GUS activity was also observed in non-vascular tissues of GPA-infested leaves, thus raising the possibility that a combination of distinct PAD4 activities in vascular and non-vascular tissues contribute to Arabidopsis defense against GPA.

  15. Defence responses of arabidopsis thaliana to infection by pseudomonas syringae are regulated by the circadian clock

    KAUST Repository

    Bhardwaj, Vaibhav

    2011-10-31

    The circadian clock allows plants to anticipate predictable daily changes in abiotic stimuli, such as light; however, whether the clock similarly allows plants to anticipate interactions with other organisms is unknown. Here we show that Arabidopsis thaliana (Arabidopsis) has circadian clock-mediated variation in resistance to the virulent bacterial pathogen Pseudomonas syringae pv. tomato DC3000 (Pst DC3000), with plants being least susceptible to infection in the subjective morning. We suggest that the increased resistance to Pst DC3000 observed in the morning in Col-0 plants results from clock-mediated modulation of pathogen associated molecular pattern (PAMP)-triggered immunity. Analysis of publicly available microarray data revealed that a large number of Arabidopsis defence-related genes showed both diurnal- and circadian-regulation, including genes involved in the perception of the PAMP flagellin which exhibit a peak in expression in the morning. Accordingly, we observed that PAMP-triggered callose deposition was significantly higher in wild-type plants inoculated with Pst DC3000 hrpA in the subjective morning than in the evening, while no such temporal difference was evident in arrhythmic plants. Our results suggest that PAMP-triggered immune responses are modulated by the circadian clock and that temporal regulation allows plants to anticipate and respond more effectively to pathogen challenges in the daytime. © 2011 Bhardwaj et al.

  16. Novel sulI binary vectors enable an inexpensive foliar selection method in Arabidopsis

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    Smith Jamison

    2011-03-01

    Full Text Available Abstract Background Sulfonamide resistance is conferred by the sulI gene found on many Enterobacteriaceae R plasmids and Tn21 type transposons. The sulI gene encodes a sulfonamide insensitive dihydropteroate synthase enzyme required for folate biosynthesis. Transformation of tobacco, potato or Arabidopsis using sulI as a selectable marker generates sulfadiazine-resistant plants. Typically sulI-based selection of transgenic plants is performed on tissue culture media under sterile conditions. Findings A set of novel binary vectors containing a sulI selectable marker expression cassette were constructed and used to generate transgenic Arabidopsis. We demonstrate that the sulI selectable marker can be utilized for direct selection of plants grown in soil with a simple foliar spray application procedure. A highly effective and inexpensive high throughput screening strategy to identify transgenic Arabidopsis without use of tissue culture was developed. Conclusion Novel sulI-containing Agrobacterium binary vectors designed to over-express a gene of interest or to characterize a test promoter in transgenic plants have been constructed. These new vector tools combined with the various beneficial attributes of sulfonamide selection and the simple foliar screening strategy provide an advantageous alternative for plant biotechnology researchers. The set of binary vectors is freely available upon request.

  17. Hydrogen sulfide improves drought tolerance in Arabidopsis thaliana by microRNA expressions.

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    Jiejie Shen

    Full Text Available Hydrogen sulfide (H2S is a gasotransmitter and plays an important role in many physiological processes in mammals. Studies of its functions in plants are attracting ever growing interest, for example, its ability to enhance drought resistance in Arabidopsis. A general role of microRNAs (miRNAs in plant adaptive responses to drought stress has thereby increased our interest to delve into the possible interplay between H2S and miRNAs. Our results showed that treating wild type (WT Arabidopsis seedlings with polyethylene glycol 8000 (PEG8000 to simulate drought stress caused an increase in production rate of endogenous H2S; and a significant transcriptional reformation of relevant miRNAs, which were also triggered by exogenous H2S in WT. When lcd mutants (with lower H2S production rate than WT were treated with PEG8000, they showed lower levels of miRNA expression changes than WT. In addition, we detected significant changes in target gene expression of those miRNAs and the corresponding phenotypes in lcd, including less roots, retardation of leaf growth and development and greater superoxide dismutase (SOD activity under drought stress. We thereby conclude that H2S can improve drought resistance through regulating drought associated miRNAs in Arabidopsis.

  18. Mining the active proteome of Arabidopsis thaliana

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    Renier A. L. Van Der Hoorn

    2011-11-01

    Full Text Available Assigning functions to the >30.000 proteins encoded by the Arabidopsis genome is a challenging task of the Arabidopsis Functional Genomics Network. Although genome-wide technologies like proteomics and transcriptomics have generated a wealth of information that significantly accelerated gene annotation, protein activities are poorly predicted by transcript or protein levels as protein activities are post-translationally regulated. To directly display protein activities in Arabidopsis proteomes, we developed and applied Activity-based Protein Profiling (ABPP. ABPP is based on the use of small molecule probes that react with the catalytic residues of distinct protein classes in an activity-dependent manner. Labeled proteins are separated and detected from proteins gels and purified and identified by mass spectrometry. Using probes of six different chemotypes we have displayed of activities of 76 Arabidopsis proteins. These proteins represent over ten different protein classes that contain over 250 Arabidopsis proteins, including cysteine- serine- and metallo-proteases, lipases, acyltransferases, and the proteasome. We have developed methods for identification of in vivo labeled proteins using click-chemistry and for in vivo imaging with fluorescent probes. In vivo labeling has revealed novel protein activities and unexpected subcellular activities of the proteasome. Labeling of extracts displayed several differential activities e.g. of the proteasome during immune response and methylesterases during infection. These studies illustrate the power of ABPP to display the functional proteome and testify to a successful interdisciplinary collaboration involving chemical biology, organic chemistry and proteomics.

  19. Repression of the Auxin Response Pathway Increases Arabidopsis Susceptibility to Necrotrophic Fungi

    Institute of Scientific and Technical Information of China (English)

    Francisco Llorente; Paul Muskett; Andrea Sánchez-Vallet; Gemma López; Brisa Ramos; Clara Sánchez-Rodríguez; Lucia Jordá; Jane Parker; Antonio Molina

    2008-01-01

    In plants, resistance to necrotrophic pathogens depends on the interplay between different hormone systems, such as those regulated by salicylic acid (SA), jasmonic acid (JA), ethylene, and abscisic acid. Repression of auxin signaling by the SA pathway was recently shown to contribute to antibacterial resistance. Here, we demonstrate that Arabidopsis auxin signaling mutants axrl, axr2, and axr6 that have defects in the auxin-stimulated SCF (Skpl-Cullin-F-box) ubiquitination pathway exhibit increased susceptibility to the necrotrophic fungi Plectosphaerella cucumerina and Botrytis cinerea. Also, stabilization of the auxin transcriptional repressor AXR3 that is normally targeted for removal by the SCF-ubiquitin/proteasome machinery occurs upon P. cucumerina infection. Pharmacological inhibition of auxin transport or proteasome function each compromise necrotroph resistance of wild-type plants to a similar extent as in non-treated auxin response mutants. These results suggest that auxin signaling is important for resistance to the necrotrophic fungi P. cucumerina and B. cinerea. SGTlb (one of two Arabidopsis SGT1 genes encoding HSP90/HSC70 co-chaperones) promotes the functions of SCF E3-ubiquitin ligase complexes in auxin and JA responses and resistance conditioned by certain Resistance (R) genes to biotrophic pathogens. We find that sgtlb mutants are as resistant to P. cucumerina as wild-type plants. Conversely, auxin/SCF signaling mutants are uncompromised in RPP4-triggered resistance to the obligate biotrophic oomycete, Hyaloperonospora parasitica. Thus, the predominant action of SGTlb in R gene-conditioned resistance to oomycetes appears to be at a site other than assisting SCF E3-ubiquitin ligases. However, genetic additivity of sgtlb axr1 double mutants in susceptibility to H. parasitica suggests that SCF-mediated ubiquitination contributes to limiting biotrophic pathogen colonization once plant-pathogen compatibility is established.

  20. Riboflavin-induced Priming for Pathogen Defense in Arabidopsis thaliana

    Institute of Scientific and Technical Information of China (English)

    Shujian Zhang; Xue Yang; Maowu Sun; Feng Sun; Sheng Deng; Hansong Dong

    2009-01-01

    Riboflavin (vitamin B2) participates in a variety of redox processes that affect plant defense responses. Previously we have shown that riboflavin induces pathogen resistance in the absence of hypersensitive cell death (HCD) in plants. Herein, we report that riboflavin induces priming of defense responses in Arabidopsis thaliana toward infection by virulent Pseudomonas syringae pv. Tomato DC3000 (Pst). Induced resistance was mechanistically connected with the expression of defense response genes and cellular defense events, including H2O2 burst, HCD, and callose deposition in the plant. Riboflavin treatment and inoculation of plants with Pst were neither active but both synergized to induce defense responses. The priming process needed NPR1 (essential regulator of systemic acquired resistance) and maintenance of H2O2 burst but was independent of salicylic acid, jasmonic acid, ethylene, and abscisic acid. Our results suggest that the role of riboflavin in priming defenses is subject to a signaling process distinct from the known pathways of hormone signal transduction.

  1. Recent Progress in Arabidopsis Research in China: A Preface

    Institute of Scientific and Technical Information of China (English)

    Zhi-Hong Xu

    2006-01-01

    @@ In 2002, a workshop on Arabidopsis research in China was held in Shanghai, when a small group of Chinese plant scientists was working on this model species. Since then, we have witnessed the rapid growth of Arabidopsis research in China. This special issue of Journal of Integrative Plant Biology is dedicated exclusively to the Fourth Workshop on Arabidopsis Research in China, scheduled on November 30, 2005, in Beijing. In addition to reports collected in this special issue, the Chinese Arabidopsis community has been able to make significant contributions to many research fields. Here, I briefly summarize recent advances in Arabidopsis research in China.

  2. Functional characterization of aroA from Rhizobium leguminosarum with significant glyphosate tolerance in transgenic Arabidopsis.

    Science.gov (United States)

    Han, Jing; Tian, Yong-Sheng; Xu, Jing; Wang, Li-Juan; Wang, Bo; Peng, Ri-He; Yao, Quan-Hong

    2014-09-01

    Glyphosate is the active component of the top-selling herbicide, the phytotoxicity of which is due to its inhibition of the shikimic acid pathway. 5-Enolpyruvylshikimate-3-phosphate synthase (EPSPS) is a key enzyme in the shikimic acid pathway. Glyphosate tolerance in plants can be achieved by the expression of a glyphosate-insensitive aroA gene (EPSPS). In this study, we used a PCR-based two-step DNA synthesis method to synthesize a new aroA gene (aroAR. leguminosarum) from Rhizobium leguminosarum. In vitro glyphosate sensitivity assays showed that aroAR. leguminosarum is glyphosate tolerant. The new gene was then expressed in E. coli and key kinetic values of the purified enzyme were determined. Furthermore, we transformed the aroA gene into Arabidopsis thaliana by the floral dip method. Transgenic Arabidopsis with the aroAR. leguminosarum gene was obtained to prove its potential use in developing glyphosate-resistant crops.

  3. The arabidopsis cyclic nucleotide interactome

    KAUST Repository

    Donaldson, Lara

    2016-05-11

    Background Cyclic nucleotides have been shown to play important signaling roles in many physiological processes in plants including photosynthesis and defence. Despite this, little is known about cyclic nucleotide-dependent signaling mechanisms in plants since the downstream target proteins remain unknown. This is largely due to the fact that bioinformatics searches fail to identify plant homologs of protein kinases and phosphodiesterases that are the main targets of cyclic nucleotides in animals. Methods An affinity purification technique was used to identify cyclic nucleotide binding proteins in Arabidopsis thaliana. The identified proteins were subjected to a computational analysis that included a sequence, transcriptional co-expression and functional annotation analysis in order to assess their potential role in plant cyclic nucleotide signaling. Results A total of twelve cyclic nucleotide binding proteins were identified experimentally including key enzymes in the Calvin cycle and photorespiration pathway. Importantly, eight of the twelve proteins were shown to contain putative cyclic nucleotide binding domains. Moreover, the identified proteins are post-translationally modified by nitric oxide, transcriptionally co-expressed and annotated to function in hydrogen peroxide signaling and the defence response. The activity of one of these proteins, GLYGOLATE OXIDASE 1, a photorespiratory enzyme that produces hydrogen peroxide in response to Pseudomonas, was shown to be repressed by a combination of cGMP and nitric oxide treatment. Conclusions We propose that the identified proteins function together as points of cross-talk between cyclic nucleotide, nitric oxide and reactive oxygen species signaling during the defence response.

  4. Arabidopsis thaliana natural variation reveals connections between UV radiation stress and plant pathogen-like defense responses.

    Science.gov (United States)

    Piofczyk, Thomas; Jeena, Ganga; Pecinka, Ales

    2015-08-01

    UV radiation is a ubiquitous component of solar radiation that affects plant growth and development. Here we studied growth related traits of 345 Arabidopsis thaliana accessions in response to UV radiation stress. We analyzed the genetic basis of this natural variation by genome-wide association studies, which suggested a specific candidate genomic region. RNA-sequencing of three sensitive and three resistant accessions combined with mutant analysis revealed five large effect genes. Mutations in PHE ammonia lyase 1 (PAL1) and putative kinase At1g76360 rendered Arabidopsis hypersensitive to UV stress, while loss of function from putative methyltransferase At4g22530, novel plant snare 12 (NPSN12) and defense gene activated disease resistance 2 (ADR2) conferred higher UV stress resistance. Three sensitive accessions showed strong ADR2 transcriptional activation, accumulation of salicylic acid (SA) and dwarf growth upon UV stress, while these phenotypes were much less affected in resistant plants. The phenotype of sensitive accessions resembles autoimmune reactions due to overexpression of defense related genes, and suggests that natural variation in response to UV radiation stress is driven by pathogen-like responses in Arabidopsis.

  5. Reference: 510 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available ch stabilizes the water-oxidizing complex, is represented in Arabidopsis thaliana (Arabidopsis) by two isofo...rms. Two T-DNA insertion mutant lines deficient in either the PsbO1 or the PsbO2 protein were re...ally. Both PsbO proteins were able to support the oxygen evolution activity of PSII, although PsbO2 was less... efficient than PsbO1 under photoinhibitory conditions. Prolonged high light stress led to re...duced growth and fitness of the mutant lacking PsbO2 as compared with the wild type and the muta

  6. Reference: 59 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available 59 http://metadb.riken.jp/db/SciNetS_ria224i/cria224u4ria224u14563930i Kaczorowski Kare...naling network in Arabidopsis, we used a sensitized genetic screen for deetiolation-defective seedlings. Two allelic mutants were... isolated that exhibited reduced sensitivity to both continuous red and far-re...d light, suggesting involvement in both phyA and phyB signaling. The molecular lesions res...ponsible for the phenotype were shown to be mutations in the Arabidopsis PSEUDO-RESPONSE REGULATOR7 (PRR7) g

  7. Reference: 756 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available elle et al. 2008 Jun. Plant Physiol. 147(2):595-610. Treatment of Arabidopsis (Arabidopsis thaliana) alterna...tive oxidase1a (aox1a) mutant plants with moderate light under drought conditions resulted in a phenotypic difference compare...d with ecotype Columbia (Col-0), as evidenced by a 10-fold incre...ase in the accumulation of anthocyanins in leaves, alterations in photosynthetic efficiency, and increased superoxide radical and re...duced root growth at the early stages of seedling growth. Analysis of metabolite profiles re

  8. Gibberellins control fruit patterning in Arabidopsis thaliana.

    Science.gov (United States)

    Arnaud, Nicolas; Girin, Thomas; Sorefan, Karim; Fuentes, Sara; Wood, Thomas A; Lawrenson, Tom; Sablowski, Robert; Østergaard, Lars

    2010-10-01

    The Arabidopsis basic helix-loop-helix (bHLH) proteins INDEHISCENT (IND) and ALCATRAZ (ALC) specify tissues required for fruit opening that have major roles in seed dispersal and plant domestication. Here, we show that synthesis of the phytohormone gibberellin is a direct and necessary target of IND, and that ALC interacts directly with DELLA repressors, which antagonize ALC function but are destabilized by gibberellin. Thus, the gibberellin/DELLA pathway has a key role in patterning the Arabidopsis fruit, and the interaction between DELLA and bHLH proteins, previously shown to connect gibberellin and light responses, is a versatile regulatory module also used in tissue patterning.

  9. Colonization of the Arabidopsis rhizosphere by fluorescent Pseudomonas spp. activates a root-specific, ethylene-responsive PR-5 gene in the vascular bundle

    NARCIS (Netherlands)

    Léon-Kloosterziel, K.M.; Verhagen, B.W.M.; Keurentjes, J.J.B.; Pelt, J.A. van; Rep, M.; Loon, L.C. van; Pieterse, C.M.J.

    2005-01-01

    Plants of which the roots are colonized by selected strains of non-pathogenic, fluorescent Pseudomonas spp. develop an enhanced defensive capacity against a broad spectrum of foliar pathogens. In Arabidopsis thaliana, this rhizobacteria-induced systemic resistance (ISR) functions independently of sa

  10. An Efficient Visual Screen for CRISPR/Cas9 Activity in Arabidopsis thaliana

    Science.gov (United States)

    Hahn, Florian; Mantegazza, Otho; Greiner, André; Hegemann, Peter; Eisenhut, Marion; Weber, Andreas P. M.

    2017-01-01

    The CRISPR/Cas9 system enables precision editing of the genome of the model plant Arabidopsis thaliana and likely of any other organism. Tools and methods for further developing and optimizing this widespread and versatile system in Arabidopsis would hence be welcomed. Here, we designed a generic vector system that can be used to clone any sgRNA sequence in a plant T-DNA vector containing an ubiquitously expressed Cas9 gene. With this vector, we explored two alternative marker systems for tracking Cas9-mediated gene-editing in vivo: BIALAPHOS RESISTANCE (BAR) and GLABROUS1 (GL1). BAR confers resistance to glufosinate and is widely used as a positive selection marker; GL1 is required for the formation of trichomes. Reversion of a frameshift null BAR allele to a functional one by Cas9-mediated gene editing yielded a higher than expected number of plants that are resistant to glufosinate. Surprisingly, many of those plants did not display reversion of the BAR gene through the germline. We hypothesize that few BAR revertant cells in a highly chimeric plant likely provide system-wide resistance to glufosinate and thus we suggest that BAR is not suitable as marker for tracking Cas9-mediated gene-editing. Targeting the GL1 gene for disruption with Cas9 provided clearly visible phenotypes of partially and completely glabrous plants. 50% of the analyzed T1 plants produced descendants with a chimeric phenotype and we could recover fully homozygous plants in the T3 generation with high efficiency. We propose that targeting of GL1 is suitable for assessing and optimizing Cas9-mediated gene-editing in Arabidopsis. PMID:28174584

  11. Arabidopsis EDS1 connects pathogen effector recognition to cell compartment-specific immune responses.

    Science.gov (United States)

    Heidrich, Katharina; Wirthmueller, Lennart; Tasset, Céline; Pouzet, Cécile; Deslandes, Laurent; Parker, Jane E

    2011-12-01

    Pathogen effectors are intercepted by plant intracellular nucleotide binding-leucine-rich repeat (NB-LRR) receptors. However, processes linking receptor activation to downstream defenses remain obscure. Nucleo-cytoplasmic basal resistance regulator EDS1 (ENHANCED DISEASE SUSCEPTIBILITY1) is indispensible for immunity mediated by TIR (Toll-interleukin-1 receptor)-NB-LRR receptors. We show that Arabidopsis EDS1 molecularly connects TIR-NB-LRR disease resistance protein RPS4 recognition of bacterial effector AvrRps4 to defense pathways. RPS4-EDS1 and AvrRps4-EDS1 complexes are detected inside nuclei of living tobacco cells after transient coexpression and in Arabidopsis soluble leaf extracts after resistance activation. Forced AvrRps4 localization to the host cytoplasm or nucleus reveals cell compartment-specific RPS4-EDS1 defense branches. Although nuclear processes restrict bacterial growth, programmed cell death and transcriptional resistance reinforcement require nucleo-cytoplasmic coordination. Thus, EDS1 behaves as an effector target and activated TIR-NB-LRR signal transducer for defenses across cell compartments.

  12. GH3-mediated auxin homeostasis links growth regulation with stress adaptation response in Arabidopsis.

    Science.gov (United States)

    Park, Jung-Eun; Park, Ju-Young; Kim, Youn-Sung; Staswick, Paul E; Jeon, Jin; Yun, Ju; Kim, Sun-Young; Kim, Jungmook; Lee, Yong-Hwan; Park, Chung-Mo

    2007-03-30

    Plants constantly monitor environmental fluctuations to optimize their growth and metabolism. One example is adaptive growth occurring in response to biotic and abiotic stresses. Here, we demonstrate that GH3-mediated auxin homeostasis is an essential constituent of the complex network of auxin actions that regulates stress adaptation responses in Arabidopsis. Endogenous auxin pool is regulated, at least in part, through negative feedback by a group of auxin-inducible GH3 genes encoding auxin-conjugating enzymes. An Arabidopsis mutant, wes1-D, in which a GH3 gene WES1 is activated by nearby insertion of the (35)S enhancer, exhibited auxin-deficient traits, including reduced growth and altered leaf shape. Interestingly, WES1 is also induced by various stress conditions as well as by salicylic acid and abscisic acid. Accordingly, wes1-D was resistant to both biotic and abiotic stresses, and stress-responsive genes, such as pathogenesis-related genes and CBF genes, were upregulated in this mutant. In contrast, a T-DNA insertional mutant showed reduced stress resistance. We therefore propose that GH3-mediated growth suppression directs reallocation of metabolic resources to resistance establishment and represents the fitness costs of induced resistance.

  13. Rice blast fungus (Magnaporthe oryzae) infects Arabidopsis via a mechanism distinct from that required for the infection of rice.

    Science.gov (United States)

    Park, Ju-Young; Jin, Jianming; Lee, Yin-Won; Kang, Seogchan; Lee, Yong-Hwan

    2009-01-01

    Magnaporthe oryzae is a hemibiotrophic fungal pathogen that causes rice (Oryza sativa) blast. Although M. oryzae as a whole infects a wide variety of monocotyledonous hosts, no dicotyledonous plant has been reported as a host. We found that two rice pathogenic strains of M. oryzae, KJ201 and 70-15, interacted differentially with 16 ecotypes of Arabidopsis (Arabidopsis thaliana). Strain KJ201 infected all ecotypes with varying degrees of virulence, whereas strain 70-15 caused no symptoms in certain ecotypes. In highly susceptible ecotypes, small chlorotic lesions appeared on infected leaves within 3 d after inoculation and subsequently expanded across the affected leaves. The fungus produced spores in susceptible ecotypes but not in resistant ecotypes. Fungal cultures recovered from necrotic lesions caused the same symptoms in healthy plants, satisfying Koch's postulates. Histochemical analyses showed that infection by the fungus caused an accumulation of reactive oxygen species and eventual cell death. Similar to the infection process in rice, the fungus differentiated to form appressorium and directly penetrated the leaf surface in Arabidopsis. However, the pathogenic mechanism in Arabidopsis appears distinct from that in rice; three fungal genes essential for pathogenicity in rice played only limited roles in causing disease symptoms in Arabidopsis, and the fungus seems to colonize Arabidopsis as a necrotroph through the secretion of phytotoxic compounds, including 9,12-octadecadienoic acid. Expression of PR-1 and PDF1.2 was induced in response to infection by the fungus, suggesting the activation of salicylic acid- and jasmonic acid/ethylene-dependent signaling pathways. However, the roles of these signaling pathways in defense against M. oryzae remain unclear. In combination with the wealth of genetic and genomic resources available for M. oryzae, this newly established pathosystem allows comparison of the molecular and cellular mechanisms underlying

  14. The Identification of Maize and Arabidopsis Type I FLAVONE SYNTHASEs Links Flavones with Hormones and Biotic Interactions.

    Science.gov (United States)

    Falcone Ferreyra, María Lorena; Emiliani, Julia; Rodriguez, Eduardo José; Campos-Bermudez, Valeria Alina; Grotewold, Erich; Casati, Paula

    2015-10-01

    Flavones are a major group of flavonoids with diverse functions and are extensively distributed in land plants. There are two different classes of FLAVONE SYNTHASE (FNS) enzymes that catalyze the conversion of the flavanones into flavones. The FNSI class comprises soluble Fe(2+)/2-oxoglutarate-dependent dioxygenases, and FNSII enzymes are oxygen- and NADPH-dependent cytochrome P450 membrane-bound monooxygenases. Here, we describe the identification and characterization of FNSI enzymes from maize (Zea mays) and Arabidopsis (Arabidopsis thaliana). In maize, ZmFNSI-1 is expressed at significantly higher levels in silks and pericarps expressing the 3-deoxy flavonoid R2R3-MYB regulator P1, suggesting that ZmFNSI-1 could be the main enzyme for the synthesis of flavone O-glycosides. We also show here that DOWNY MILDEW RESISTANT6 (AtDMR6), the Arabidopsis homologous enzyme to ZmFNSI-1, has FNSI activity. While dmr6 mutants show loss of susceptibility to Pseudomonas syringae, transgenic dmr6 plants expressing ZmFNSI-1 show similar susceptibility to wild-type plants, demonstrating that ZmFNSI-1 can complement the mutant phenotype. AtDMR6 expression analysis showed a tissue- and developmental stage-dependent pattern, with high expression in cauline and senescing leaves. Finally, we show that Arabidopsis cauline and senescing leaves accumulate apigenin, demonstrating that Arabidopsis plants have an FNSI activity involved in the biosynthesis of flavones. The results presented here also suggest cross talk between the flavone and salicylic acid pathways in Arabidopsis; in this way, pathogens would induce flavones to decrease salicylic acid and, hence, increase susceptibility.

  15. Overexpression of OsWRKY72 gene interferes in the abscisic acid signal and auxin transport pathway of Arabidopsis

    Indian Academy of Sciences (India)

    Song Yu; Chen Ligang; Zhang Liping; Yu Diqiu

    2010-09-01

    Through activating specific transcriptional programmes, plants can launch resistance mechanisms to stressful environments and acquire a new equilibrium between development and defence. To screen the rice WRKY transcription factor which functions in abiotic stress tolerance and modulates the abscisic acid (ABA) response, we generated a whole array of 35S-OsWRKY transgenic Arabidopsis. In this study, we report that 35S-OsWRKY72 transgenic Arabidopsis, whose seed germination was retarded under normal conditions, emerged more sensitive to mannitol, NaCl, ABA stresses and sugar starvation than vector plants. Meanwhile, 35S-OsWRKY72 transgenic Arabidopsis displayed early flowering, reduced apical dominance, lost high temperature-induced hypocotyl elongation response, and enhanced gravitropism response, which were similar to the auxin-related gene mutants aux1, axr1 and bud1. Further, semi-quantitative RT-PCR showed that the expression patterns of three auxin-related genes AUX1, AXR1 and BUD1 were significantly altered in rosette leaves and inflorescences of 35S-OsWRKY72 plants compared with control Arabidopsis, and two ABA-related genes ABA2 and ABI4 were induced in 35S-OsWRKY72 seedlings. In addition, northern blot analysis indicated that, in rice, OsWRKY72 was inducible by polyethylene glycol (PEG), NaCl, naphthalene acetic acid (NAA), ABA and 42°C, similar to its orthologue AtWRKY75 in Arabidopsis, implying that these two WRKY genes might be required for multiple physiological processes in their plants. Together, these results suggest that OsWRKY72 interferes in the signal cross-talk between the ABA signal and auxin transport pathway in transgenic Arabidopsis.

  16. Arabidopsis CDS blastp result: AK242890 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242890 J090079L19 At2g32540.1 68415.m03975 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 4e-47 ...

  17. Arabidopsis CDS blastp result: AK242585 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242585 J090010M20 At5g16910.1 68418.m01982 cellulose synthase family protein similar to gi:2827143 cellulo...se synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 1e-28 ...

  18. Arabidopsis CDS blastp result: AK242601 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242601 J090014G03 At4g23990.1 68417.m03448 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 2e-26 ...

  19. Arabidopsis CDS blastp result: AK242601 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242601 J090014G03 At2g32540.1 68415.m03975 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 2e-45 ...

  20. Arabidopsis CDS blastp result: AK242601 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242601 J090014G03 At5g16910.1 68418.m01982 cellulose synthase family protein similar to gi:2827143 cellulo...se synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 0.0 ...

  1. Arabidopsis CDS blastp result: AK242585 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242585 J090010M20 At1g32180.1 68414.m03958 cellulose synthase family protein similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose synthase-9 (gi:9622890) from Zea mays 1e-24 ...

  2. Arabidopsis CDS blastp result: AK242585 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242585 J090010M20 At5g16910.1 68418.m01982 cellulose synthase family protein similar to gi:2827143 cellulo...se synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 2e-65 ...

  3. Arabidopsis CDS blastp result: AK110534 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK110534 002-168-A07 At5g16910.1 cellulose synthase family protein similar to gi:2827143 cellulose... synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 1e-114 ...

  4. Arabidopsis CDS blastp result: AK242890 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242890 J090079L19 At2g32530.1 68415.m03974 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 4e-50 ...

  5. Arabidopsis CDS blastp result: AK242601 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242601 J090014G03 At4g38190.1 68417.m05391 cellulose synthase family protein similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose synthase-5 (gi:9622882) from Zea mays 0.0 ...

  6. Arabidopsis CDS blastp result: AK242601 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242601 J090014G03 At4g23990.1 68417.m03448 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 5e-25 ...

  7. Arabidopsis CDS blastp result: AK242585 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242585 J090010M20 At2g32530.1 68415.m03974 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 8e-98 ...

  8. Arabidopsis CDS blastp result: AK061162 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK061162 006-209-A01 At2g32540.1 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 3e-35 ...

  9. Arabidopsis CDS blastp result: AK242601 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242601 J090014G03 At1g32180.1 68414.m03958 cellulose synthase family protein similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose synthase-9 (gi:9622890) from Zea mays 0.0 ...

  10. Arabidopsis CDS blastp result: AK242585 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242585 J090010M20 At1g32180.1 68414.m03958 cellulose synthase family protein similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose synthase-9 (gi:9622890) from Zea mays 3e-66 ...

  11. Arabidopsis CDS blastp result: AK069071 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK069071 J023010H01 At2g32540.1 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 1e-167 ...

  12. Arabidopsis CDS blastp result: AK121003 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK121003 J023045B21 At2g32540.1 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 1e-167 ...

  13. Arabidopsis CDS blastp result: AK242890 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242890 J090079L19 At4g23990.1 68417.m03448 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 1e-45 ...

  14. Arabidopsis CDS blastp result: AK242585 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242585 J090010M20 At2g32540.1 68415.m03975 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 4e-98 ...

  15. Arabidopsis CDS blastp result: AK060286 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK060286 001-006-C08 At2g32540.1 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 6e-78 ...

  16. Arabidopsis CDS blastp result: AK242890 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242890 J090079L19 At4g38190.1 68417.m05391 cellulose synthase family protein similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose synthase-5 (gi:9622882) from Zea mays 1e-125 ...

  17. Arabidopsis CDS blastp result: AK242601 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242601 J090014G03 At4g23990.1 68417.m03448 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 8e-25 ...

  18. Arabidopsis CDS blastp result: AK242601 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242601 J090014G03 At2g32540.1 68415.m03975 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 3e-31 ...

  19. Arabidopsis CDS blastp result: AK242890 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242890 J090079L19 At5g16910.1 68418.m01982 cellulose synthase family protein similar to gi:2827143 cellulo...se synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 1e-130 ...

  20. Arabidopsis CDS blastp result: AK105393 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK105393 001-123-B04 At5g16910.1 cellulose synthase family protein similar to gi:2827143 cellulose... synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 0.0 ...

  1. Arabidopsis CDS blastp result: AK242601 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242601 J090014G03 At2g32530.1 68415.m03974 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 5e-48 ...

  2. Arabidopsis CDS blastp result: AK242601 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242601 J090014G03 At2g32530.1 68415.m03974 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 2e-29 ...

  3. Arabidopsis CDS blastp result: AK109812 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK109812 002-147-H02 At5g16910.1 cellulose synthase family protein similar to gi:2827143 cellulose... synthase catalytic subunit, Arabidopsis thaliana, gi:9622886 cellulose synthase-7 from Zea mays 5e-90 ...

  4. Arabidopsis CDS blastp result: AK242585 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242585 J090010M20 At4g38190.1 68417.m05391 cellulose synthase family protein similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose synthase-5 (gi:9622882) from Zea mays 8e-63 ...

  5. Arabidopsis CDS blastp result: AK242890 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242890 J090079L19 At1g32180.1 68414.m03958 cellulose synthase family protein similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose synthase-9 (gi:9622890) from Zea mays 1e-126 ...

  6. Arabidopsis CDS blastp result: AK242585 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242585 J090010M20 At4g23990.1 68417.m03448 cellulose synthase family protein similar to cellulose... synthase catalytic subunit from Arabidopsis thaliana [gi:5230423], cellulose synthase-5 from Zea mays [gi:9622882] 1e-124 ...

  7. Arabidopsis CDS blastp result: AK242585 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242585 J090010M20 At4g38190.1 68417.m05391 cellulose synthase family protein similar to cellulose... synthase catalytic subunit gi:2827143 from [Arabidopsis thaliana], cellulose synthase-5 (gi:9622882) from Zea mays 4e-27 ...

  8. Reference: 415 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available study focuses on the seven other Arabidopsis CAD for which functions are not yet elucidated. Their expression patterns were determine...ession of CAD 1, B1, and G genes was determined using their promoters fused to the GUS reporter gene. CAD 1

  9. Arabidopsis CDS blastp result: AK243408 [KOME

    Lifescience Database Archive (English)

    Full Text Available subunit ClpX, putative similar to CLP protease regulatory subunit CLPX GI:2674203 from [Arabidopsis thaliana]; non-consensus... splice donor GC at exon 4; non-consensus splice donor AA at exon 7 1e-151 ...

  10. Arabidopsis CDS blastp result: AK242797 [KOME

    Lifescience Database Archive (English)

    Full Text Available subunit ClpX, putative similar to CLP protease regulatory subunit CLPX GI:2674203 from [Arabidopsis thaliana]; non-consensus... splice donor GC at exon 4; non-consensus splice donor AA at exon 7 2e-23 ...

  11. Arabidopsis CDS blastp result: AK243408 [KOME

    Lifescience Database Archive (English)

    Full Text Available subunit ClpX, putative similar to CLP protease regulatory subunit CLPX GI:2674203 from [Arabidopsis thaliana]; non-consensus... splice donor GC at exon 4; non-consensus splice donor AA at exon 7 2e-12 ...

  12. Reference: 767 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available Arabidopsis thaliana genome. Mutation analysis of 25 of the 27 member genes representing 13 of the 14 sub-families... of the UBP gene family revealed that single-gene mutants of three genes in two sub-families exhibit v

  13. Reference: 158 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available onika et al. 2005 Feb. Plant J. 41(3):386-99. Cullin proteins, which belong to multigenic families in all eu...ic search revealed the existence of at least 76 BTB-domain proteins in Arabidopsis belonging to 11 major families.... Yeast two-hybrid experiments indicate that representative members of certain families are able to phy

  14. Reference: 456 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available h other Spo11/topo VIA proteins, but their functional relationship during meiosis or other processes is not ...s. Thus, the three Arabidopsis Spo11 homologues appear to function in two discrete processes, i.e. AtSPO11-1

  15. Reference: 412 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available the tobacco arcA gene, mediates hormone responses and plays a regulatory role in multiple developmental processes...in RACK1A confer defects in multiple developmental processes including seed germination, leaf production, an...ltiple hormone responsiveness and developmental processes in Arabidopsis. 11 2697-708 16829549 2006 Journal

  16. Reference: 51 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available urce of acetyl-CoA formation in the plastids of plants and is composed of multiple copies of four different ...astidic E2 (dihydrolipoyl acetyltransferase) subunit, plE2, of the complex in Arabidopsis destroys the expre

  17. Reference: 567 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available ith findings that noxy2 and mutants with defective 9-LOX activity showed increased numbers of lateral roots,...or of lateral root formation. Histochemical and molecular analyses revealed that 9-HOT activated events comm...in Arabidopsis regulate lateral root development and defense responses through a specific signaling cascade.

  18. Arabidopsis CDS blastp result: AK287911 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK287911 J065213B08 At1g12110.1 68414.m01402 nitrate/chlorate transporter (NRT1.1) ...(CHL1) identical to nitrate/chlorate transporter SP:Q05085 from [Arabidopsis thaliana]; contains Pfam profile: PF00854 POT family 3e-85 ...

  19. Arabidopsis CDS blastp result: AK318551 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK318551 J075138M12 At1g12110.1 68414.m01402 nitrate/chlorate transporter (NRT1.1) ...(CHL1) identical to nitrate/chlorate transporter SP:Q05085 from [Arabidopsis thaliana]; contains Pfam profile: PF00854 POT family 4e-27 ...

  20. Arabidopsis CDS blastp result: AK241823 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241823 J065212G21 At1g12110.1 68414.m01402 nitrate/chlorate transporter (NRT1.1) ...(CHL1) identical to nitrate/chlorate transporter SP:Q05085 from [Arabidopsis thaliana]; contains Pfam profile: PF00854 POT family 1e-150 ...

  1. Arabidopsis CDS blastp result: AK243378 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK243378 J100063A13 At1g12110.1 68414.m01402 nitrate/chlorate transporter (NRT1.1) ...(CHL1) identical to nitrate/chlorate transporter SP:Q05085 from [Arabidopsis thaliana]; contains Pfam profile: PF00854 POT family 5e-18 ...

  2. Arabidopsis CDS blastp result: AK288351 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK288351 J090024C17 At1g12110.1 68414.m01402 nitrate/chlorate transporter (NRT1.1) ...(CHL1) identical to nitrate/chlorate transporter SP:Q05085 from [Arabidopsis thaliana]; contains Pfam profile: PF00854 POT family 2e-24 ...

  3. Arabidopsis CDS blastp result: AK242252 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242252 J075182G16 At1g12110.1 68414.m01402 nitrate/chlorate transporter (NRT1.1) ...(CHL1) identical to nitrate/chlorate transporter SP:Q05085 from [Arabidopsis thaliana]; contains Pfam profile: PF00854 POT family 6e-88 ...

  4. Arabidopsis CDS blastp result: AK073411 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK073411 J033041P20 At4g02060.1 prolifera protein (PRL) / DNA replication licensing... factor Mcm7 (MCM7) identical to DNA replication licensing factor Mcm7 SP|P43299 PROLIFERA protein {Arabidopsis thaliana}; contains Pfam profile PF00493: MCM2/3/5 family 0.0 ...

  5. Arabidopsis CDS blastp result: AK100867 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK100867 J023124E13 At2g29640.1 josephin family protein contains Pfam domain PF02099: Jose...phin; similar to Josephin-like protein (Swiss-Prot:O82391) [Arabidopsis thaliana] 7e-59 ...

  6. Arabidopsis CDS blastp result: AK241402 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241402 J065159A02 At4g19070.1 68417.m02810 cadmium-responsive protein / cadmium i...nduced protein (AS8) identical to cadmium induced protein AS8 SP:P42735 from [Arabidopsis thaliana] 3e-11 ...

  7. Proteomics of Arabidopsis seed germination and priming

    NARCIS (Netherlands)

    Gallardo, K.; Job, C.; Groot, S.P.C.; Puype, M.; Demol, H.; Vandekerckhove, J.; Job, D.

    2003-01-01

    To better understand seed germination, a complex developmental process, we developed a proteome analysis of the model plant Arabidopsis for which complete genome sequence is now available. Among about 1,300 total seed proteins resolved in two-dimensional gels, changes in the abundance (up- and down-

  8. Arabidopsis CDS blastp result: AK241096 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241096 J065076O13 At3g10520.1 68416.m01262 non-symbiotic hemoglobin 2 (HB2) (GLB2...) identical to SP|O24521 Non-symbiotic hemoglobin 2 (Hb2) (ARAth GLB2) {Arabidopsis thaliana} 1e-40 ...

  9. Arabidopsis CDS blastp result: AK240885 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK240885 J065029A17 At3g10520.1 68416.m01262 non-symbiotic hemoglobin 2 (HB2) (GLB2...) identical to SP|O24521 Non-symbiotic hemoglobin 2 (Hb2) (ARAth GLB2) {Arabidopsis thaliana} 6e-34 ...

  10. Arabidopsis CDS blastp result: AK241096 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241096 J065076O13 At2g16060.1 68415.m01841 non-symbiotic hemoglobin 1 (HB1) (GLB1...) identical to SP|O24520 Non-symbiotic hemoglobin 1 (Hb1) (ARAth GLB1) {Arabidopsis thaliana} 1e-59 ...

  11. Arabidopsis CDS blastp result: AK240885 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK240885 J065029A17 At2g16060.1 68415.m01841 non-symbiotic hemoglobin 1 (HB1) (GLB1...) identical to SP|O24520 Non-symbiotic hemoglobin 1 (Hb1) (ARAth GLB1) {Arabidopsis thaliana} 3e-49 ...

  12. Protease gene families in Populus and Arabidopsis

    Directory of Open Access Journals (Sweden)

    Jansson Stefan

    2006-12-01

    Full Text Available Abstract Background Proteases play key roles in plants, maintaining strict protein quality control and degrading specific sets of proteins in response to diverse environmental and developmental stimuli. Similarities and differences between the proteases expressed in different species may give valuable insights into their physiological roles and evolution. Results We have performed a comparative analysis of protease genes in the two sequenced dicot genomes, Arabidopsis thaliana and Populus trichocarpa by using genes coding for proteases in the MEROPS database 1 for Arabidopsis to identify homologous sequences in Populus. A multigene-based phylogenetic analysis was performed. Most protease families were found to be larger in Populus than in Arabidopsis, reflecting recent genome duplication. Detailed studies on e.g. the DegP, Clp, FtsH, Lon, rhomboid and papain-Like protease families showed the pattern of gene family expansion and gene loss was complex. We finally show that different Populus tissues express unique suites of protease genes and that the mRNA levels of different classes of proteases change along a developmental gradient. Conclusion Recent gene family expansion and contractions have made the Arabidopsis and Populus complements of proteases different and this, together with expression patterns, gives indications about the roles of the individual gene products or groups of proteases.

  13. Arabidopsis CDS blastp result: AK241728 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241728 J065199H08 At1g50310.1 68414.m05640 monosaccharide transporter (STP9) iden...tical to monosaccharide transporter STP9 protein [Arabidopsis thaliana] GI:15487254; contains Pfam profile PF00083: major facilitator superfamily protein 3e-36 ...

  14. Arabidopsis CDS blastp result: AK240645 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK240645 J023003B03 At1g50310.1 68414.m05640 monosaccharide transporter (STP9) iden...tical to monosaccharide transporter STP9 protein [Arabidopsis thaliana] GI:15487254; contains Pfam profile PF00083: major facilitator superfamily protein 1e-17 ...

  15. Arabidopsis CDS blastp result: AK243302 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK243302 J100054J17 At1g50310.1 68414.m05640 monosaccharide transporter (STP9) iden...tical to monosaccharide transporter STP9 protein [Arabidopsis thaliana] GI:15487254; contains Pfam profile PF00083: major facilitator superfamily protein 4e-82 ...

  16. Arabidopsis CDS blastp result: AK241015 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241015 J065054A13 At1g50310.1 68414.m05640 monosaccharide transporter (STP9) iden...tical to monosaccharide transporter STP9 protein [Arabidopsis thaliana] GI:15487254; contains Pfam profile PF00083: major facilitator superfamily protein 8e-37 ...

  17. Arabidopsis CDS blastp result: AK288091 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK288091 J075184D14 At1g50310.1 68414.m05640 monosaccharide transporter (STP9) iden...tical to monosaccharide transporter STP9 protein [Arabidopsis thaliana] GI:15487254; contains Pfam profile PF00083: major facilitator superfamily protein 4e-29 ...

  18. Arabidopsis CDS blastp result: AK318617 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK318617 J100090H20 At1g19850.1 68414.m02490 transcription factor MONOPTEROS (MP) /... auxin-responsive protein (IAA24) / auxin response factor 5 (ARF5) identical to transcription factor MONOPTEROS (MP/IAA24/ARF5) SP:P93024 from [Arabidopsis thaliana] 2e-63 ...

  19. Arabidopsis CDS blastp result: AK103452 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK103452 J033129I11 At1g19850.1 transcription factor MONOPTEROS (MP) / auxin-respon...sive protein (IAA24) / auxin response factor 5 (ARF5) identical to transcription factor MONOPTEROS (MP/IAA24/ARF5) SP:P93024 from [Arabidopsis thaliana] 1e-166 ...

  20. Arabidopsis CDS blastp result: AK243230 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK243230 J100044L04 At1g19850.1 68414.m02490 transcription factor MONOPTEROS (MP) /... auxin-responsive protein (IAA24) / auxin response factor 5 (ARF5) identical to transcription factor MONOPTEROS (MP/IAA24/ARF5) SP:P93024 from [Arabidopsis thaliana] 2e-65 ...

  1. Reference: 346 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available 346 http://metadb.riken.jp/db/SciNetS_ria224i/cria224u4ria224u16496096i Todd Christopher...midohydrolase activity from Arabidopsis thaliana. 5 1108-13 16496096 2006 Apr Planta Polacco Joe C|Todd Christopher D

  2. Arabidopsis CDS blastp result: AK242980 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242980 J090094F15 At3g58780.1 68416.m06551 agamous-like MADS box protein AGL1 / shatterproof... 1 (AGL1) (SHP1) identical to SP|P29381 Agamous-like MADS box protein AGL1 (Protein Shatterproof 1) {Arabidopsis thaliana} 2e-19 ...

  3. Arabidopsis CDS blastp result: AK241644 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241644 J065189M04 At3g58780.1 68416.m06551 agamous-like MADS box protein AGL1 / shatterproof... 1 (AGL1) (SHP1) identical to SP|P29381 Agamous-like MADS box protein AGL1 (Protein Shatterproof 1) {Arabidopsis thaliana} 3e-37 ...

  4. Arabidopsis CDS blastp result: AK241055 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241055 J065063N18 At3g58780.1 68416.m06551 agamous-like MADS box protein AGL1 / shatterproof... 1 (AGL1) (SHP1) identical to SP|P29381 Agamous-like MADS box protein AGL1 (Protein Shatterproof 1) {Arabidopsis thaliana} 1e-26 ...

  5. Arabidopsis CDS blastp result: AK242211 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK242211 J075171C16 At3g58780.1 68416.m06551 agamous-like MADS box protein AGL1 / shatterproof... 1 (AGL1) (SHP1) identical to SP|P29381 Agamous-like MADS box protein AGL1 (Protein Shatterproof 1) {Arabidopsis thaliana} 5e-21 ...

  6. Arabidopsis CDS blastp result: AK243669 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK243669 J100089N11 At3g58780.1 68416.m06551 agamous-like MADS box protein AGL1 / shatterproof... 1 (AGL1) (SHP1) identical to SP|P29381 Agamous-like MADS box protein AGL1 (Protein Shatterproof 1) {Arabidopsis thaliana} 6e-14 ...

  7. Arabidopsis CDS blastp result: AK100613 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK100613 J023107M18 At4g10180.1 light-mediated development protein 1 / deetiolated1... (DET1) identical to Light-mediated development protein DET1 (Deetiolated1) (Swiss-Prot:P48732) [Arabidopsis thaliana] 0.0 ...

  8. Arabidopsis CDS blastp result: AK058683 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK058683 001-019-A06 At4g10180.1 light-mediated development protein 1 / deetiolated...1 (DET1) identical to Light-mediated development protein DET1 (Deetiolated1) (Swiss-Prot:P48732) [Arabidopsis thaliana] 0.0 ...

  9. Arabidopsis CDS blastp result: AK241645 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241645 J065189N07 At5g20000.1 68418.m02380 26S proteasome AAA-ATPase subunit, putative almost... identical to 26S proteasome AAA-ATPase subunit RPT6a GI:6652888 from [Arabidopsis thaliana]; almost

  10. Arabidopsis CDS blastp result: AK243043 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK243043 J100008P08 At5g20000.1 68418.m02380 26S proteasome AAA-ATPase subunit, putative almost... identical to 26S proteasome AAA-ATPase subunit RPT6a GI:6652888 from [Arabidopsis thaliana]; almost

  11. Arabidopsis CDS blastp result: AK241277 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241277 J065134P20 At5g20000.1 68418.m02380 26S proteasome AAA-ATPase subunit, putative almost... identical to 26S proteasome AAA-ATPase subunit RPT6a GI:6652888 from [Arabidopsis thaliana]; almost

  12. Arabidopsis CDS blastp result: AK241074 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241074 J065068E03 At5g20000.1 68418.m02380 26S proteasome AAA-ATPase subunit, putative almost... identical to 26S proteasome AAA-ATPase subunit RPT6a GI:6652888 from [Arabidopsis thaliana]; almost

  13. Reference: 386 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available 386 http://metadb.riken.jp/db/SciNetS_ria224i/cria224u4ria224u16698900i Hricová Andrea...d mesophyll cell proliferation in Arabidopsis. 3 942-56 16698900 2006 Jul Plant physiology Hricová Andrea|Micol José Luis|Quesada Victor

  14. Reference: 394 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available 394 http://metadb.riken.jp/db/SciNetS_ria224i/cria224u4ria224u16766689i Rudella Andrea...and defects in chloroplast biogenesis in Arabidopsis. 7 1704-21 16766689 2006 Jul The Plant cell Alonso Jose M|Ecker Joseph R|Friso Giulia|Rudella Andrea|van Wijk Klaas J

  15. Arabidopsis CDS blastp result: AK243428 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK243428 J100067L15 At5g14750.1 68418.m01731 myb family transcription factor (MYB66) / werewolf...iption factor (MYB66) mRNA, partial cds GI:3941491; identical to GP:9755743 myb transcription factor werewolf (WER)/ MYB66 {Arabidopsis thaliana} 8e-36 ...

  16. Arabidopsis CDS blastp result: AK288699 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK288699 J090061C22 At5g14750.1 68418.m01731 myb family transcription factor (MYB66) / werewolf...iption factor (MYB66) mRNA, partial cds GI:3941491; identical to GP:9755743 myb transcription factor werewolf (WER)/ MYB66 {Arabidopsis thaliana} 8e-36 ...

  17. Arabidopsis CDS blastp result: AK243271 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK243271 J100049K04 At5g14750.1 68418.m01731 myb family transcription factor (MYB66) / werewolf...iption factor (MYB66) mRNA, partial cds GI:3941491; identical to GP:9755743 myb transcription factor werewolf (WER)/ MYB66 {Arabidopsis thaliana} 4e-35 ...

  18. Arabidopsis CDS blastp result: AK241812 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241812 J065210K15 At5g14750.1 68418.m01731 myb family transcription factor (MYB66) / werewolf...iption factor (MYB66) mRNA, partial cds GI:3941491; identical to GP:9755743 myb transcription factor werewolf (WER)/ MYB66 {Arabidopsis thaliana} 1e-22 ...

  19. Arabidopsis CDS blastp result: AK241549 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241549 J065176M15 At5g14750.1 68418.m01731 myb family transcription factor (MYB66) / werewolf...iption factor (MYB66) mRNA, partial cds GI:3941491; identical to GP:9755743 myb transcription factor werewolf (WER)/ MYB66 {Arabidopsis thaliana} 3e-32 ...

  20. Arabidopsis CDS blastp result: AK241615 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241615 J065186D02 At5g14750.1 68418.m01731 myb family transcription factor (MYB66) / werewolf...iption factor (MYB66) mRNA, partial cds GI:3941491; identical to GP:9755743 myb transcription factor werewolf (WER)/ MYB66 {Arabidopsis thaliana} 8e-35 ...

  1. Arabidopsis CDS blastp result: AK288487 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK288487 J090040H24 At5g14750.1 68418.m01731 myb family transcription factor (MYB66) / werewolf...iption factor (MYB66) mRNA, partial cds GI:3941491; identical to GP:9755743 myb transcription factor werewolf (WER)/ MYB66 {Arabidopsis thaliana} 5e-37 ...

  2. Arabidopsis CDS blastp result: AK287469 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK287469 J043021L20 At5g14750.1 68418.m01731 myb family transcription factor (MYB66) / werewolf...iption factor (MYB66) mRNA, partial cds GI:3941491; identical to GP:9755743 myb transcription factor werewolf (WER)/ MYB66 {Arabidopsis thaliana} 2e-36 ...

  3. Arabidopsis CDS blastp result: AK241370 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241370 J065154C10 At5g14750.1 68418.m01731 myb family transcription factor (MYB66) / werewolf...iption factor (MYB66) mRNA, partial cds GI:3941491; identical to GP:9755743 myb transcription factor werewolf (WER)/ MYB66 {Arabidopsis thaliana} 2e-31 ...

  4. Arabidopsis CDS blastp result: AK288415 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK288415 J090031E07 At5g14750.1 68418.m01731 myb family transcription factor (MYB66) / werewolf...iption factor (MYB66) mRNA, partial cds GI:3941491; identical to GP:9755743 myb transcription factor werewolf (WER)/ MYB66 {Arabidopsis thaliana} 3e-37 ...

  5. Arabidopsis CDS blastp result: AK287447 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK287447 J043016O04 At2g46590.1 68415.m05811 Dof zinc finger protein DAG2 / Dof affecting germination... 2 (DAG2) identical to SP|Q9ZPY0 DOF zinc finger protein DAG2 (Dof affecting germination 2) {Arabidopsis thaliana} 2e-30 ...

  6. Arabidopsis CDS blastp result: AK241364 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK241364 J065152E11 At2g46590.1 68415.m05811 Dof zinc finger protein DAG2 / Dof affecting germination... 2 (DAG2) identical to SP|Q9ZPY0 DOF zinc finger protein DAG2 (Dof affecting germination 2) {Arabidopsis thaliana} 2e-20 ...

  7. Arabidopsis CDS blastp result: AK242393 [KOME

    Lifescience Database Archive (English)

    Full Text Available ctor, putative / enhancer of shoot regeneration (ESR1) similar to gb|D38124 EREBP-3 from Nicotiana tabacum a...nd contains PF|00847 AP2 domain; identical to cDNA enhancer of shoot regeneration ESR1 GI:18028939, enhancer of shoot regeneration ESR1 [Arabidopsis thaliana] GI:18028940 3e-13 ...

  8. Arabidopsis CDS blastp result: AK241281 [KOME

    Lifescience Database Archive (English)

    Full Text Available ctor, putative / enhancer of shoot regeneration (ESR1) similar to gb|D38124 EREBP-3 from Nicotiana tabacum a...nd contains PF|00847 AP2 domain; identical to cDNA enhancer of shoot regeneration ESR1 GI:18028939, enhancer of shoot regeneration ESR1 [Arabidopsis thaliana] GI:18028940 1e-12 ...

  9. Arabidopsis CDS blastp result: AK241762 [KOME

    Lifescience Database Archive (English)

    Full Text Available ctor, putative / enhancer of shoot regeneration (ESR1) similar to gb|D38124 EREBP-3 from Nicotiana tabacum a...nd contains PF|00847 AP2 domain; identical to cDNA enhancer of shoot regeneration ESR1 GI:18028939, enhancer of shoot regeneration ESR1 [Arabidopsis thaliana] GI:18028940 9e-17 ...

  10. Arabidopsis CDS blastp result: AK242986 [KOME

    Lifescience Database Archive (English)

    Full Text Available ctor, putative / enhancer of shoot regeneration (ESR1) similar to gb|D38124 EREBP-3 from Nicotiana tabacum a...nd contains PF|00847 AP2 domain; identical to cDNA enhancer of shoot regeneration ESR1 GI:18028939, enhancer of shoot regeneration ESR1 [Arabidopsis thaliana] GI:18028940 1e-13 ...

  11. Arabidopsis CDS blastp result: AK287689 [KOME

    Lifescience Database Archive (English)

    Full Text Available avonol 3-O-methyltransferase 1 / caffeic acid/5-hydroxyferulic acid O-methyltransferase (OMT1) identical to ...1.1.76) (AtOMT1) (Flavonol 3- O-methyltransferase 1) (Caffeic acid/5-hydroxyferulic acid O- methyltransferase) {Arabidopsis thaliana} 5e-23 ...

  12. Arabidopsis CDS blastp result: AK240736 [KOME

    Lifescience Database Archive (English)

    Full Text Available avonol 3-O-methyltransferase 1 / caffeic acid/5-hydroxyferulic acid O-methyltransferase (OMT1) identical to ...1.1.76) (AtOMT1) (Flavonol 3- O-methyltransferase 1) (Caffeic acid/5-hydroxyferulic acid O- methyltransferase) {Arabidopsis thaliana} 1e-22 ...

  13. Arabidopsis CDS blastp result: AK241705 [KOME

    Lifescience Database Archive (English)

    Full Text Available avonol 3-O-methyltransferase 1 / caffeic acid/5-hydroxyferulic acid O-methyltransferase (OMT1) identical to ...1.1.76) (AtOMT1) (Flavonol 3- O-methyltransferase 1) (Caffeic acid/5-hydroxyferulic acid O- methyltransferase) {Arabidopsis thaliana} 1e-11 ...

  14. Arabidopsis CDS blastp result: AK287483 [KOME

    Lifescience Database Archive (English)

    Full Text Available avonol 3-O-methyltransferase 1 / caffeic acid/5-hydroxyferulic acid O-methyltransferase (OMT1) identical to ...1.1.76) (AtOMT1) (Flavonol 3- O-methyltransferase 1) (Caffeic acid/5-hydroxyferulic acid O- methyltransferase) {Arabidopsis thaliana} 1e-37 ...

  15. Arabidopsis CDS blastp result: AK107208 [KOME

    Lifescience Database Archive (English)

    Full Text Available Ala hydrolase, putative virtually identical to gr1-protein from [Arabidopsis thaliana] GI:3559811; similar t...AK107208 002-125-B11 At1g44350.1 IAA-amino acid hydrolase 6, putative (ILL6) / IAA-

  16. Arabidopsis CDS blastp result: AK062144 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK062144 001-045-G08 At5g54080.2 homogentisate 1,2-dioxygenase / homogentisicase/ho... (EC 1.13.11.5) (Homogentisicase) (Homogentisate oxygenase) (Homogentisic acid oxidase) {Arabidopsis thaliana}; contains Pfam profile PF04209: homogentisate 1,2-dioxygenase 1e-155 ...

  17. Arabidopsis CDS blastp result: AK061294 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK061294 006-301-D01 At3g08900.1 reversibly glycosylated polypeptide-3 (RGP3) nearl...y identical to reversibly glycosylated polypeptide-3 [Arabidopsis thaliana] GI:11863238; contains non-consensus GA-donor splice site at intron 2 0.0 ...

  18. Reference: 119 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available of the Arabidopsis homolog of MSH4 (AtMSH4). We demonstrate that AtMSH4 expression can only be detected in floral tissues, consisten...chromosomes. A T-DNA insertional mutant (Atmsh4) exhibited normal vegetative growth but a severe reduction in fertility, consistent

  19. Reference: 428 [Arabidopsis Phenome Database[Archive

    Lifescience Database Archive (English)

    Full Text Available on was delayed in the psb27 mutant, suggesting that Psb27 is required for efficient...icient repair of photodamaged photosystem II. 4-5 567-75...he involvement of this lumenal protein in the recovery process of PSII. A Psb27 homologue in Arabidopsis thaliana is required for eff

  20. Arabidopsis CDS blastp result: AK105724 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK105724 001-201-G07 At1g07110.1 fructose-6-phosphate 2-kinase / fructose-2,6-bisph...osphatase (F2KP) identical to fructose-6-phosphate 2-kinase/fructose-2,6-bisphosphatase (F2KP) [Arabidopsis thaliana] GI:13096098 0.0 ...