methyl-jasmonate has been researched along with ethephon* in 46 studies
46 other study(ies) available for methyl-jasmonate and ethephon
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NaMLP, a new identified Kunitz trypsin inhibitor regulated synergistically by JA and ethylene, confers Spodoptera litura resistance in Nicotiana attenuata.
We identified a miraculin-like protein (NaMLP) who is a new Kunitz trypsin inhibitor regulated synergistically by JA and ethylene signals and confers Spodoptera litura resistance in wild tobacco Nicotiana attenuata. The findings revealed a new source of trypsin inhibitor activities after herbivory, and provide new insights into the complexity of the regulation of trypsin inhibitor-based defense after insect herbivore attack. Upon insect herbivore attack, wild tobacco Nicotiana attenuata accumulates trypsin protease inhibitor (TPI) activities as a defense response from different protease inhibitor (PI) coding genes, including WRKY3-regulated NaKTI2, and JA-dependent NaPI. However, whether any other TPI gene exists in N. attenuata is still unclear. A miraculin-like protein gene (NaMLP) was highly up-regulated in N. attenuata after Alternaria alternata infection. However, silencing or overexpression of NaMLP had no effect on the lesion diameter developed on N. attenuata leaves after A. alternata inoculation. Meanwhile, the transcripts of NaMLP could be induced by wounding and amplified by Spodoptera litura oral secretions (OS). S. litura larvae gained significantly more biomass on NaMLP-silenced plants but less on NaMLP overexpressed plants. Although NaMLP showed low sequence similarity to NaKTI2, it had conserved reaction sites of Kunitz trypsin inhibitors, and exhibited TPI activities when its coding gene was overexpressed transiently or stably in N. attenuata. This was consistent with the worst performance of S. litura larvae on NaMLP overexpressed lines. Furthermore, NaMLP-silenced plants had reduced TPI activities and better S. litura performance. Finally, OS-elicited NaMLP was dramatically reduced in JA-deficient AOC silencing and ethylene-reduced ACO-silencing plants, and the expression of NaMLP could be significantly induced by methyl jasmonate or ethephon alone, but dramatically amplified by co-treatment of both methyl jasmonate and ethephon. Thus, our results demonstrate that in addition to JA-regulated NaPI, and WRKY3/6-dependent NaKTI2, N. attenuata plants also up-regulates TPI activities via NaMLP, which confers S. litura resistance through JA and ethylene signaling pathways in a synergistic way. Topics: Animals; Cyclopentanes; Ethylenes; Herbivory; Nicotiana; Oxylipins; Plant Proteins; Protease Inhibitors; Spodoptera; Trypsin Inhibitors | 2023 |
Salt and osmotic stress seriously restrict the growth, development, and productivity of horticultural crops in the greenhouse. The papain-like cysteine proteases (PLCPs) participate in multi-stress responses in plants. We previously demonstrated that salt and osmotic stress affect cysteine protease 15 of pepper ( Topics: Antioxidants; Capsicum; Mannitol; Osmoregulation; Salicylic Acid; Sodium Chloride | 2023 |
Silencing a Simple Extracellular Leucine-Rich Repeat Gene
Many plant proteins with extracellular leucine-rich repeat (eLRR) domains play an important role in plant immunity. However, the role of one class of eLRR plant proteins-the simple eLRR proteins-in plant defenses against herbivores remains largely unknown. Here, we found that a simple eLRR protein OsI-BAK1 in rice localizes to the plasma membrane. Its expression was induced by mechanical wounding, the infestation of gravid females of brown planthopper (BPH) Topics: Abscisic Acid; Acetates; Animals; Cyclopentanes; Ethylenes; Female; Gene Expression Regulation, Plant; Gene Silencing; Hemiptera; Leucine; Organophosphorus Compounds; Oryza; Oviposition; Oxylipins; Plant Defense Against Herbivory; Plant Immunity; Plant Proteins; Plants, Genetically Modified; Transcription Factors | 2021 |
Effects of palmitic acid (16:0), hexacosanoic acid (26:0), ethephon and methyl jasmonate on the cuticular wax composition, structure and expression of key gene in the fruits of three pear cultivars.
The chemical composition, crystal morphology and expression levels of associated genes involved in the cuticular wax of three pear cultivars 'Housui', 'Cuiguan' and 'Yuluxiang' after treatment with palmitic acid (PA), hexacosanoic acid (HA), ethephon and methyl jasmonate (Meja) were determined. A total of 59 cuticular wax compounds were detected across all samples. The wax coverage of 'Housui' fruits increased by 71.74, 93.48 and 89.13% after treatment with PA, ethephon and Meja, respectively, and treatment with PA, HA and Meja also increased the wax coverage in 'Cuiguan' (65.33, 20.00 and 21.33% respectively) and in 'Yuluxiang' (38.60, 63.16 and 42.11% respectively) fruits. Heatmap clustering analysis and partial least-squares-discriminate analysis (PLS-DA) also revealed that the different treatments exerted various influences on cuticular wax among the different cultivars. In addition, the wax component coverage and wax crystal structures showed variations among the different cultivars as well as different treatments. Gene expression analysis revealed 11 genes likely to be involved in pear fruit wax synthesis, transport and regulation. Taken together, the results of this study demonstrate that the differences in the cuticular waxes of the fruits of different cultivars after treatment with PA, HA, ethephon or Meja might lead to a better understanding of the regulatory effect of a substrate or elicitor on the composition and deposition of cuticular waxes. Topics: Acetates; Cyclopentanes; Fatty Acids; Fruit; Organophosphorus Compounds; Oxylipins; Palmitic Acid; Pyrus; Waxes | 2020 |
Enhanced accumulation of harpagide and 8-O-acetyl-harpagide in Melittis melissophyllum L. agitated shoot cultures analyzed by UPLC-MS/MS.
Harpagide and its derivatives have valuable medicinal properties, such as anti-inflammatory, analgesic and potential antirheumatic effects. There is the demand for searching plant species containing these iridoids or developing biotechnological methods to obtain the compounds. The present study investigated the effects of methyl jasmonate (MeJa, 50 μM), ethephon (Eth, 50 μM) and L-phenylalanine (L-Phe, 2.4 g/L of medium), added to previously selected variant of Murashige and Skoog medium (supplemented with plant growth regulators: 6-benzylaminopurine 1.0 mg/L, α-naphthaleneacetic acid 0.5 mg/L, gibberellic acid 0.25 mg/L) on the accumulation of harpagide and 8-O-acetyl-harpagide in Melittis melissophyllum L. agitated shoot cultures. Plant material was harvested 2 and 8 days after the supplementation. Iridoids were quantitatively analyzed by the UPLC-MS/MS method in extracts from the biomass and the culture medium. It was found that all of the variants caused an increase in the accumulation of harpagide. In the biomass harvested after 2 days, the highest harpagide content of 247.3 mg/100 g DW was found for variant F (L-Phe and Eth), and the highest 8-O-acetyl-harpagide content of 138 mg/100 g DW for variant E (L-Phe and MeJa). After 8 days, in some variants, a portion of the metabolites was released into the culture medium. Considering the total amount of the compounds (in the biomass and medium), the highest accumulation of harpagide, amounting to 619 mg/100 g DW, was found in variant F, and the highest amount of 8-O-acetyl-harpagide, of 255.4 mg/100 g DW, was found in variant H (L-Phe, MeJa, Eth) when harvested on the 8th day. These amounts were, respectively, 24.7 and 4.8 times higher than in the control culture, and were, respectively, 15 and 6.7 times higher than in the leaves of the soil-grown plant. The total amount of the two iridoids was highest for variant F (0.78% DW) and variant H (0.68% DW) when harvested on the 8th day. The results indicate that the agitated shoot cultures of M. melissophyllum can be a rich source of harpagide and 8-O-acetyl-harpagide, having a potential practical application. To the best of our knowledge we present for the first time the results of the quantitative UPLC-MS/MS analysis of harpagide and 8-O-acetyl-harpagide in M. melissophyllum shoot cultures and the enhancement of their accumulation by means of medium supplementation with elicitors and precursor. Topics: Acetates; Chromatography, High Pressure Liquid; Culture Media; Cyclopentanes; Iridoid Glycosides; Iridoids; Lamiaceae; Mass Spectrometry; Organophosphorus Compounds; Oxylipins; Phenylalanine; Plant Leaves; Plant Shoots; Pyrans | 2018 |
CaHDZ27, a Homeodomain-Leucine Zipper I Protein, Positively Regulates the Resistance to Ralstonia solanacearum Infection in Pepper.
Homeodomain-leucine zipper class I (HD-Zip I) transcription factors have been functionally characterized in plant responses to abiotic stresses, but their roles in plant immunity are poorly understood. Here, a HD-Zip I gene, CaHZ27, was isolated from pepper (Capsicum annum) and characterized for its role in pepper immunity. Quantitative real-time polymerase chain reaction showed that CaHDZ27 was transcriptionally induced by Ralstonia solanacearum inoculation and exogenous application of methyl jasmonate, salicylic acid, or ethephon. The CaHDZ27-green fluorescent protein fused protein was targeted exclusively to the nucleus. Chromatin immunoprecipitation demonstrated that CaHDZ27 bound to the 9-bp pseudopalindromic element (CAATAATTG) and triggered β-glucuronidase expression in a CAATAATTG-dependent manner. Virus-induced gene silencing of CaHDZ27 significantly attenuated the resistance of pepper plants against R. solanacearum and downregulated defense-related marker genes, including CaHIR1, CaACO1, CaPR1, CaPR4, CaPO2, and CaBPR1. By contrast, transient overexpression of CaHDZ27 triggered strong cell death mediated by the hypersensitive response and upregulated the tested immunity-associated marker genes. Ectopic CaHDZ27 expression in tobacco enhances its resistance against R. solanacearum. These results collectively suggest that CaHDZ27 functions as a positive regulator in pepper resistance against R. solanacearum. Bimolecular fluorescence complementation and coimmunoprecipitation assays indicate that CaHDZ27 monomers bind with each other, and this binding is enhanced significantly by R. solanacearum inoculation. We speculate that homodimerization of CaHZ27 might play a role in pepper response to R. solanacearum, further direct evidence is required to confirm it. Topics: Acetates; Amino Acid Sequence; Capsicum; Cell Death; Cell Nucleus; Cyclopentanes; Disease Resistance; DNA, Plant; Gene Expression Regulation, Plant; Gene Silencing; Homeodomain Proteins; Leucine Zippers; Luminescence; Nicotiana; Organophosphorus Compounds; Oxylipins; Plant Diseases; Plant Immunity; Plant Leaves; Plant Proteins; Plants, Genetically Modified; Protein Binding; Protein Multimerization; Protein Transport; Ralstonia solanacearum; Salicylic Acid; Transcriptional Activation; Up-Regulation | 2017 |
Overexpression of a novel peanut NBS-LRR gene AhRRS5 enhances disease resistance to Ralstonia solanacearum in tobacco.
Bacterial wilt caused by Ralstonia solanacearum is a ruinous soilborne disease affecting more than 450 plant species. Efficient control methods for this disease remain unavailable to date. This study characterized a novel nucleotide-binding site-leucine-rich repeat resistance gene AhRRS5 from peanut, which was up-regulated in both resistant and susceptible peanut cultivars in response to R. solanacearum. The product of AhRRS5 was localized in the nucleus. Furthermore, treatment with phytohormones such as salicylic acid (SA), abscisic acid (ABA), methyl jasmonate (MeJA) and ethephon (ET) increased the transcript level of AhRRS5 with diverse responses between resistant and susceptible peanuts. Abiotic stresses such as drought and cold conditions also changed AhRRS5 expression. Moreover, transient overexpression induced hypersensitive response in Nicotiana benthamiana. Overexpression of AhRRS5 significantly enhanced the resistance of heterogeneous tobacco to R. solanacearum, with diverse resistance levels in different transgenic lines. Several defence-responsive marker genes in hypersensitive response, including SA, JA and ET signals, were considerably up-regulated in the transgenic lines as compared with the wild type inoculated with R. solanacearum. Nonexpressor of pathogenesis-related gene 1 (NPR1) and non-race-specific disease resistance 1 were also up-regulated in response to the pathogen. These results indicate that AhRRS5 participates in the defence response to R. solanacearum through the crosstalk of multiple signalling pathways and the involvement of NPR1 and R gene signals for its resistance. This study may guide the resistance enhancement of peanut and other economic crops to bacterial wilt disease. Topics: Abscisic Acid; Acetates; Arachis; Base Sequence; Cell Nucleus; Cold Temperature; Cyclopentanes; Disease Resistance; Droughts; Gene Expression Regulation, Plant; Genes, Plant; Genetic Vectors; Nicotiana; Organophosphorus Compounds; Oxylipins; Phylogeny; Plant Diseases; Plant Growth Regulators; Plant Proteins; Plants, Genetically Modified; Ralstonia solanacearum; Salicylic Acid; Sequence Alignment; Stress, Physiological; Transcription Factors; Up-Regulation | 2017 |
Comparative proteomic analysis of latex from Hevea brasiliensis treated with Ethrel and methyl jasmonate using iTRAQ-coupled two-dimensional LC-MS/MS.
Ethrel (ET) is an effective and widely used latex yield stimulant of Hevea brasiliensis (Pará rubber tree), and jasmonate (JA) is a key inducer of laticifer differentiation in this plant. To examine variations in the latex proteome caused by these phytohormones, ET and methyl jasmonate (MeJA) were applied to Reyan 7-33-97 rubber tree clones, and comparative proteomic analyses were conducted. On the basis of a transcriptome shotgun assembly (TSA) sequence database and an iTRAQ-coupled two-dimensional LC-MS/MS approach, 1499 latex proteins belonging to 1078 clusters were identified. With a 1.5-fold cut-off value to determine up- and down-regulated proteins, a total of 101 latex proteins were determined to be regulated by ET and/or MeJA via pairwise comparisons among the three exposure durations (0 h, 6 h, and 48 h). Proteins associated with latex regeneration, including phosphoenolpyruvate carboxylase and acetyl-CoA C-acetyltransferase, and those associated with latex flow, such as chitinase and a sieve element occlusion protein, were affected by the application of ET. Chitinase and polyphenol oxidase were also found to be regulated by MeJA. The findings of this study may provide new insight into the roles of phytohormones in latex yield and the causative mechanisms of laticifer differentiation in rubber trees.. On the basis of a transcriptome shotgun assembly (TSA) sequence database and an iTRAQ-coupled two-dimensional LC-MS/MS approach, the most comprehensive proteome of the latex was profiled, and the ethylene-/jasmonate-responsive proteins were identified in the latex of H. brasiliensis. The findings of this study may provide new insight into the role of phytohormones in latex yield and the causative mechanisms of laticifer differentiation in rubber trees. Topics: Acetates; Chromatography, Liquid; Cyclopentanes; Hevea; Latex; Mass Spectrometry; Organophosphorus Compounds; Oxylipins; Peptide Mapping; Plant Extracts; Proteome | 2016 |
CaCDPK15 positively regulates pepper responses to Ralstonia solanacearum inoculation and forms a positive-feedback loop with CaWRKY40 to amplify defense signaling.
CaWRKY40 is a positive regulator of pepper (Capsicum annum) response to Ralstonia solanacearum inoculation (RSI), but the underlying mechanism remains largely unknown. Here, we functionally characterize CaCDPK15 in the defense signaling mediated by CaWRKY40. Pathogen-responsive TGA, W, and ERE boxes were identified in the CaCDPK15 promoter (pCaCDPK15), and pCaCDPK15-driven GUS expression was significantly enhanced in response to RSI and exogenously applied salicylic acid, methyl jasmonate, abscisic acid, and ethephon. Virus-induced gene silencing (VIGS) of CaCDPK15 significantly increased the susceptibility of pepper to RSI and downregulated the immunity-associated markers CaNPR1, CaPR1, and CaDEF1. By contrast, transient CaCDPK15 overexpression significantly activated hypersensitive response associated cell death, upregulated the immunity-associated marker genes, upregulated CaWRKY40 expression, and enriched CaWRKY40 at the promoters of its targets genes. Although CaCDPK15 failed to interact with CaWRKY40, the direct binding of CaWRKY40 to pCaCDPK15 was detected by chromatin immunoprecipitation, which was significantly potentiated by RSI in pepper plants. These combined results suggest that RSI in pepper induces CaCDPK15 and indirectly activates downstream CaWRKY40, which in turn potentiates CaCDPK15 expression. This positive-feedback loop would amplify defense signaling against RSI and efficiently activate strong plant immunity. Topics: Abscisic Acid; Acetates; Capsicum; Cell Death; Cyclopentanes; Disease Resistance; Gene Expression Regulation, Plant; Gene Silencing; Hydrogen Peroxide; Organophosphorus Compounds; Oxylipins; Plant Diseases; Plant Growth Regulators; Promoter Regions, Genetic; Protein Binding; Protein Kinases; Ralstonia solanacearum; Salicylic Acid; Signal Transduction; Transcription Factors | 2016 |
Hormonal regulation of gummosis and composition of gums from bulbs of hyacinth (Hyacinthus orientalis).
Hyacinth (Hyacinthus orientalis) bulbs infected by Fusarium oxysporum showed the symptoms of gummosis. The purpose of this study was to clarify the hormonal regulation of gummosis and composition of gums from hyacinth bulbs. The application of ethephon (2-chloroethylphosphonic acid), an ethylene-releasing compound, at 2% (w/w, in lanolin) induced gummosis in hyacinth bulbs. Methyl jasmonate (JA-Me) at 1.5% (w/w, in lanolin) induced gummosis as well. Simultaneous application of JA-Me and ethephon further enhanced gummosis. Molecular mass distribution of hyacinth gums analyzed by gel permeation chromatography indicated that the gums were mainly homogenous polysaccharides with an average molecular weight of ca. 30kDa. Analysis of the sugar composition of the gums after hydrolysis revealed that the majority were arabinose (ca. 35%) and galactose (ca. 40%) together with small amounts of fucose, rhamnose and uronic acids (ca. 5%, respectively), suggesting that the gums are pectic arabinogalactans. These results indicate that jasmonates (JAs) interact with ethylene to stimulate sugar metabolism, producing pectic arabinogalactans, and vice versa, leading to gummosis. These findings, together with those from our previous studies in tulips (Tulipa gesneriana) and grape hyacinth (Muscari armeniacum), revealed that sugar metabolism and hormonal regulation relating to gummosis are different among species of bulbous plants. Topics: Acetates; Carbohydrates; Chromatography, Ion Exchange; Cyclopentanes; Hyacinthus; Molecular Weight; Organophosphorus Compounds; Oxylipins; Plant Diseases; Plant Growth Regulators; Plant Gums; Plant Roots; Reference Standards | 2015 |
Isolation and characterization of StERF transcription factor genes from potato (Solanum tuberosum L.).
Ethylene response factor (ERF) is a major subfamily of the AP2/ERF family and plays significant roles in the regulation of abiotic- and biotic-stress responses. ERF proteins can interact with the GCC-box cis-element and then initiate a transcriptional cascade activating downstream ethylene response and enhancing plant stress tolerance. In this research, we cloned five StERF genes from potato (Solanum tuberosum L.). The expressional analysis of StERF genes revealed that they showed tissue- or organ-specific expression patterns and the expression levels in leaf, stem, root, flower, and tuber were different. The assays of quantitative real-time polymerase chain reaction (qRT-PCR) and the reverse transcription-PCR (RT-PCR) showed that the expression of five StERF genes was regulated by ethephon, methyl jasmonate (MeJA), salt and drought stress. The result from the yeast one-hybrid experiment showed that five StERFs had trans-activation activity and could specifically bind to the GCC-box cis-elements. The StERFs responded to abiotic factors and hormones suggested that they possibly had diverse roles in stress and hormone regulation of potato. Topics: Acetates; Amino Acid Sequence; Consensus Sequence; Cyclopentanes; Gene Expression Regulation, Plant; Humidity; Molecular Sequence Data; Organ Specificity; Organophosphorus Compounds; Oxylipins; Phylogeny; Plant Growth Regulators; Plant Proteins; Plant Structures; Promoter Regions, Genetic; Real-Time Polymerase Chain Reaction; Recombinant Fusion Proteins; Reverse Transcriptase Polymerase Chain Reaction; Saccharomyces cerevisiae; Salinity; Sequence Alignment; Sequence Homology, Amino Acid; Solanum tuberosum; Stress, Physiological; Transcription Factors; Transcriptional Activation | 2015 |
Overexpression of CaWRKY27, a subgroup IIe WRKY transcription factor of Capsicum annuum, positively regulates tobacco resistance to Ralstonia solanacearum infection.
WRKY proteins are encoded by a large gene family and are linked to many biological processes across a range of plant species. The functions and underlying mechanisms of WRKY proteins have been investigated primarily in model plants such as Arabidopsis and rice. The roles of these transcription factors in non-model plants, including pepper and other Solanaceae, are poorly understood. Here, we characterize the expression and function of a subgroup IIe WRKY protein from pepper (Capsicum annuum), denoted as CaWRKY27. The protein localized to nuclei and activated the transcription of a reporter GUS gene construct driven by the 35S promoter that contained two copies of the W-box in its proximal upstream region. Inoculation of pepper cultivars with Ralstonia solanacearum induced the expression of CaWRKY27 transcript in 76a, a bacterial wilt-resistant pepper cultivar, whereas it downregulated the expression of CaWRKY27 transcript in Gui-1-3, a bacterial wilt-susceptible pepper cultivar. CaWRKY27 transcript levels were also increased by treatments with salicylic acid (SA), methyl jasmonate (MeJA) and ethephon (ETH). Transgenic tobacco plants overexpressing CaWRKY27 exhibited resistance to R. solanacearum infection compared to that of wild-type plants. This resistance was coupled with increased transcript levels in a number of marker genes, including hypersensitive response genes, and SA-, JA- and ET-associated genes. By contrast, virus-induced gene silencing (VIGS) of CaWRKY27 increased the susceptibility of pepper plants to R. solanacearum infection. These results suggest that CaWRKY27 acts as a positive regulator in tobacco resistance responses to R. solanacearum infection through modulation of SA-, JA- and ET-mediated signaling pathways. Topics: Acetates; Capsicum; Cyclopentanes; Disease Resistance; Gene Expression Regulation, Plant; Gene Silencing; Host-Pathogen Interactions; Nicotiana; Organophosphorus Compounds; Oxylipins; Plant Diseases; Plant Growth Regulators; Plant Proteins; Plants, Genetically Modified; Ralstonia solanacearum; Reverse Transcriptase Polymerase Chain Reaction; Salicylic Acid; Time Factors; Transcription Factors | 2014 |
Roles of ethylene and jasmonic acid in systemic induced defense in tomato (Solanum lycopersicum) against Helicoverpa zea.
Inducible defenses that provide enhanced resistance to insect attack are nearly universal in plants. The defense-signaling cascade is mediated by the synthesis, movement, and perception of jasmonate (JA) and the interaction of this signaling molecule with other plant hormones and messengers. To explore how the interaction of JA and ethylene influences induced defenses, we employed the never-ripe (Nr) tomato mutant, which exhibits a partial block in ethylene perception, and the defenseless (def1) mutant, which is deficient in JA biosynthesis. The defense gene proteinase inhibitor (PIN2) was used as marker to compare plant responses. The Nr mutant showed a normal wounding response with PIN2 induction, but the def1 mutant did not. As expected, methyl JA (MeJA) treatment restored the normal wound response in the def1 mutant. Exogenous application of MeJA increased resistance to Helicoverpa zea, induced defense gene expression, and increased glandular trichome density on systemic leaves. Exogenous application of ethephon, which penetrates tissues and decomposes to ethylene, resulted in increased H. zea growth and interfered with the wounding response. Ethephon treatment also increased salicylic acid in systemic leaves. These results indicate that while JA plays the main role in systemic induced defense, ethylene acts antagonistically in this system to regulate systemic defense. Topics: Acetates; Animals; Cyclopentanes; Ethylenes; Gene Expression Regulation, Plant; Herbivory; Moths; Organophosphorus Compounds; Oxylipins; Plant Growth Regulators; Plant Leaves; Solanum lycopersicum; Trichomes | 2014 |
The function of Rad6 gene in Hevea brasiliensis extends beyond DNA repair.
The Rad6 gene of Saccharomyces cerevisiae encodes an ubiquitin-conjugating enzyme (E2) which is required for DNA repair, damage-induced mutagenesis, sporulation, etc. In this study, one Rad6 homolog, designated HbRad6, was cloned in rubber tree (Hevea brasiliensis). The putative protein sequence of HbRad6 contains 152 amino acids, a conserved UBC domain, and a conserved active-site cysteine in the UBC domain, which is required for E2 enzymes catalytic activity. HbRad6 shared high similarity with Rad6 from other species. It shared the highest similarity with rice OsRad6 and Arabidopsis thaliana AtUBC2 with 96.05% identical residues, and 63.16% sequence identity with yeast Rad6 (excluding the acidic tail). Comparing expression among different Hevea tissues demonstrated that HbRad6 was ubiquitously expressed in all tissues, but it revealed a preferential expression in the latex. Furthermore, HbRad6 expression was markedly induced by DNA-damaging agent H2O2, the latex stimulator ethephon (ET), and methyl jasmonate (MeJA), while NaCl and wounding treatments had relatively minor effect upon its expression. Genetic complementation experiment revealed that HbRad6 had minor effects on the complementation of the UV sensitivity of yeast rad6 null mutant, indicating that the Hevea Rad6 protein may partially suppress the UV sensitivity of the yeast rad6 mutant. These results suggested that HbRad6 was a multifunction gene involved in DNA damage repair, hormones and stress responses in rubber tree. Topics: Acetates; Amino Acid Sequence; Cloning, Molecular; Cyclopentanes; DNA Damage; DNA Repair; Evolution, Molecular; Gene Expression Regulation; Genes, Plant; Genetic Complementation Test; Hevea; Hydrogen Peroxide; Organophosphorus Compounds; Oxylipins; Phylogeny; Plant Proteins; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins; Sequence Alignment; Sodium Chloride; Stress, Mechanical; Ubiquitin-Conjugating Enzymes; Ultraviolet Rays | 2013 |
Transcription analyses of GmICHG, a gene coding for a β-glucosidase that catalyzes the specific hydrolysis of isoflavone conjugates in Glycine max (L.) Merr.
Isoflavone conjugate-hydrolyzing β-glucosidase (GmICHG) of soybeans [Glycine max (L.) Merr.] catalyzes the specific hydrolysis of isoflavone conjugates (β-7-O-(malonyl)glucosides of isoflavones) to produce free isoflavones. In this study, changes in the transcription levels of GmICHG in the individual organs of soybean seedlings (cv. Enrei) in response to microbial infection and abiotic stresses were analyzed and compared with those of genes coding for 2-hydroxyisoflavanone synthase (GmIFS) and isoflavone 7-O-glucosyltransferase (GmIF7GT). GmICHG was originally expressed in abundance only in the roots and at low levels only in the other organs. The transcription of GmICHG in the roots and other organs was suppressed upon infection of the roots by Phytophthora sojae. Upon wounding of the cotyledon, a transient long-distance up-regulation of GmICHG transcription in the roots was observed; upon fungal infection in the cotyledon, however, a delayed elevation of GmICHG transcription took place in the roots with the maximum at 10 h after the infection. Such long-distance up-regulation patterns were not observed with either GmIFS or GmIF7GT. The transcription levels of GmICHG remained essentially unchanged upon treatment of the roots with Bradyrhizobium japonicum. The transcription of GmICHG in the roots was also sensitive to a variety of stresses on the roots, such as flooding, elicitation with yeast extract, drought, and treatment with plant hormones such as abscisic, salicylic, and jasmonic acids and ethylene. Topics: Acetates; beta-Glucosidase; Biocatalysis; Biosynthetic Pathways; Bradyrhizobium; Cotyledon; Cyclopentanes; Gene Expression Profiling; Gene Expression Regulation, Plant; Genes, Plant; Glycine max; Hydrolysis; Isoflavones; Organ Specificity; Organophosphorus Compounds; Oxylipins; Phytophthora; Plant Proteins; Plant Roots; Seedlings; Stress, Physiological; Transcription, Genetic | 2013 |
Molecular characterization of VvSDIR1 from Vitis vinifera and its functional analysis by heterologous expression in Nicotiana tabacum.
The proteins harboring really interesting new gene (RING) finger domains comprise a large family and play key roles in a variety of cellular processes. One among them is the tolerance to biotic and abiotic stresses in plants. In the present study, we characterize Vitis vinifera salt- and drought-induced RING finger 1 (VvSDIR1) a homologue of the Arabidopsis SDIR1 gene obtained from V. vinifera. The VvSDIR1 gene was identified using in silico approaches and encodes a membrane-localized protein. This was evident as expression of VvSDIR1 fused with green fluorescent protein was detected in cell membrane. Southern blot analysis indicates that VvSDIR1 is present in single copy number in grape genome. The expression of VvSDIR1 gene is elevated by multiple abiotic stresses like salt, drought, cold, and heat as well as upon exogenous application of methyl jasmonate, salicylic acid, methyl viologen, abscisic acid, and ethephon. In silico analysis shows that the VvSDIR1 cDNA is 831-bp long and codes for a 276-amino acid-long protein containing a characteristic RING finger domain in its C-terminal end. Overexpression of VvSDIR1 in tobacco leads to enhanced transcript levels of many genes, homologues of which are reported to be important in regulating many stress conditions. The heterologous expression of VvSDIR1 in tobacco was found to enhance the oxidative stress tolerance in tobacco. Tobacco lines transgenic for VvSDIR1 showed enhanced tolerance to treatment with methyl viologen, NaCl, and polyethylene glycol. To the best of our knowledge, this is the first report of the heterologous expression of VvSDIR1 in oxidative stress tolerance in transgenic tobacco. Topics: Abscisic Acid; Acetates; Agrobacterium; Cyclopentanes; Nicotiana; Organophosphorus Compounds; Oxylipins; Paraquat; Plant Proteins; Plants, Genetically Modified; Salicylic Acid; Sodium Chloride; Vitis | 2013 |
Three Brassica rapa metallothionein genes are differentially regulated under various stress conditions.
The expression profiles of three Brassica rapa metallothionein genes (BrMT 1-3) were determined in 7-day-old seedlings exposed to various exogenous factors including plant hormones, heavy metals and abiotic stresses. BrMT1, BrMT2, and BrMT3 were representatives of MT gene type 1, type 2, and type 3, respectively, according to their cysteine alignment. BrMT2 showed a relatively higher basal expression level compared to BrMT1 and BrMT3 under normal conditions. The BrMT1 transcript was markedly increased by various factors including ethephon, polyethylene glycol and hydrogen peroxide, with no down-regulation evident. On the contrary, BrMT2 expression was down-regulated by abscisic acid, salicylic acid, and methyl jasmonate. Heavy metals did not increase BrMT2 expression. BrMT3 expression was only marginally and non-significantly up- and down-regulated by the stress conditions tested. Promoter regions of BrMT1 and BrMT2 display different cis-acting elements supporting the different responses of both genes against various stresses. The results demonstrate the differential regulation of BrMT1-3 by various plant exogenous factors, and indicate the utility of the BrMT1 promoter as a multiple stress inducible promoter. Topics: Abscisic Acid; Acetates; Brassica rapa; Cyclopentanes; DNA Primers; Gene Expression Profiling; Gene Expression Regulation, Plant; Hydrogen Peroxide; Metallothionein; Metals, Heavy; Organophosphorus Compounds; Oxylipins; Plant Growth Regulators; Polyethylene Glycols; Reverse Transcriptase Polymerase Chain Reaction; Salicylic Acid; Seedlings | 2012 |
Characterization of HbEREBP1, a wound-responsive transcription factor gene in laticifers of Hevea brasiliensis Muell. Arg.
AP2/ERF transcription factors play an important role in regulation of the cross-talk between ethylene and jasmonate signaling pathways mediating defense responses of plants to biotic and abiotic stresses. In this study, an AP2/ERF transcription factor gene was isolated and characterized from laticifers of rubber tree by using RACE and real time PCR. The full length cDNA, referred to as HbEREBP1, was 1,095 bp in length and contained a 732 bp open reading frame encoding a putative protein of 243 amino acid residues. The molecular mass of the putative protein is 26.4 kDa with a pI of 9.46. The deduced amino acid sequence had a specific domain of AP2 superfamily and an ethylene-responsive element binding factor-associated amphiphilic repression motif, sharing 42.4, 39.1, and 38.0% identity with that of AtERF11, AtERF4, and AtERF8 in Arabidopsis, respectively. HbEREBP1 expression was down-regulated by tapping and mechanical wounding in the laticifers of adult trees. It was also down-regulated at early stage while up-regulated at late stage upon treatment with exogenous ethephon or methyl jasmonate, which was reverse to the case of defense genes in laticifers of epicormic shoots of rubber tree. Our results suggest that HbEREBP1 may be a negative regulator of defense genes in laticifers. Topics: Acetates; Cyclopentanes; Gene Expression Regulation, Plant; Genes, Plant; Hevea; Organophosphorus Compounds; Oxylipins; Plant Diseases; Plant Proteins; Transcription Factors; Transcription, Genetic | 2012 |
Molecular characterization of peach PR genes and their induction kinetics in response to bacterial infection and signaling molecules.
'Venture' and 'BabyGold 5' are two peach cultivars with a demonstrated resistance and susceptibility, respectively, to bacterial spot disease caused by Xanthomonas campestris pv. pruni (Xcp). To explore the differences between these cultivars at the molecular level, two PR1 (Pp-PR1a, Pp-PR1b) and three PR5 (Pp-TLP1, Pp-TLP2 and Pp-TLP3) genes were isolated from peach (Prunus persica L.) and investigated by in silico and in situ approaches. The analysis of gene expression by qRT-PCR indicated that all PR genes, except Pp-PR1a, were induced to a significantly higher degree in the resistant cultivar. In response to signaling molecules, Pp-PR1a was induced chiefly by SA treatment, while other PR genes were induced mainly by ethephon or MeJA treatments. The induction of the same set of PR genes in response to bacterial infection, MeJA or ethephon suggests the involvement of jasmonic acid (JA)/ethylene (ET)-signaling pathways in mediating resistance against Xcp, which is consistent with the potential hemibiotrophic nature of this bacterium. The identification of binding sites for ERF and MYC2 transcription factors in the promoter of Pp-TLP1 and Pp-TLP2 genes further supported the role of JA/ET pathways in the transcription regulation of these genes. The role of stomata in defense against Xcp was also investigated by measuring stomatal apertures in both 'Venture' and 'BabyGold 5' leaves after 1 and 3 HPI. While most stomata closed in both cultivars within 1 HPI, stomata reopened again at 3 HPI with a higher percentage recorded for 'BabyGold 5', suggesting a potential role of stomata in the susceptibility of this cultivar. Topics: Acetates; Binding Sites; Cyclopentanes; Disease Resistance; Ethylenes; Gene Expression Regulation, Plant; Organophosphorus Compounds; Oxylipins; Plant Diseases; Plant Growth Regulators; Plant Leaves; Plant Proteins; Plant Stomata; Plants, Genetically Modified; Promoter Regions, Genetic; Prunus; RNA, Plant; Salicylic Acid; Signal Transduction; Xanthomonas campestris | 2012 |
Functional characterization of three ethylene response factor genes from Bupleurum kaoi indicates that BkERFs mediate resistance to Botrytis cinerea.
Three novel ethylene response factor (ERF) genes, BkERF1, BkERF2.1 and BkERF2.2, were isolated from a medicinal plant, Bupleurum kaoi. The deduced BkERFs contain a canonical nuclear localization signal and an ERF/AP2 DNA binding domain. RNA gel blot analysis revealed that BkERF1 and BkERF2.1 were ubiquitously expressed at low levels in all parts of mature plants, and that BkERF2.2 was expressed at moderate levels in vegetative tissues. Exogenous application of methyl jasmonate induced BkERF1/2.1/2.2 transcripts. BkERF2.2 transcript levels were slightly increased by addition of ethephon and salicylic acid. BkERFs were localized in the plant nucleus and functioned as transcriptional activators. In B. kaoi cells overexpressing BKERFs, inoculation with Botrytis cinerea increased expression of some defense genes which are associated with enhanced disease resistance. Similarly, overexpression of BkERFs in transgenic Arabidopsis thaliana resulted in elevated mRNA levels of the defense gene PDF1.2, and in enhanced resistance to B. cinerea. Collectively, these results provide evidence that BkERFs mediate the expression of defense-related genes in plants. Topics: Acetates; Anti-Infective Agents; Arabidopsis; Arabidopsis Proteins; Botrytis; Bupleurum; Cyclopentanes; Defensins; DNA, Complementary; DNA, Plant; Ethylenes; Gene Expression Regulation, Plant; Organophosphorus Compounds; Oxylipins; Plant Diseases; Plant Growth Regulators; Plant Immunity; Plant Proteins; Plants, Genetically Modified; Salicylic Acid; Signal Transduction; Transcription Factors | 2011 |
MYC genes with differential responses to tapping, mechanical wounding, ethrel and methyl jasmonate in laticifers of rubber tree (Hevea brasiliensis Muell. Arg.).
MYC2 transcription factor is a key component of the core module COI1-JAZ-MYC2 of jasmonate signaling in Arabidopsis, but the MYC transcription factor (s) associated with jasmonate signaling in jasmonate-responsive laticifer cells remains to be identified. Two full-length cDNAs, designated HblMYC1 and HblMYC2, were isolated from laticifer cells in Hevea brasiliensis by the method of RACE. HblMYC1 contained 1431bp ORF encoding a putative protein of 476 amino acids while HblMYC2 contained 1428bp ORF encoding a putative protein of 475 amino acids. Bioinformatic analysis showed that the putative proteins, HblMYC1 and HblMYC2, possessed a bHLH domain and were most related to the MYC2 among the selected 27 MYC members with identified functions in Arabidopsis. In addition to the presence of cis-regulatory elements involving jasmonate responsiveness in the promoter regions of HblMYC1 and HblMYC2, the abscisic acid-, salicylic acid- and gibberellin-responsive elements were found in the promoter region of HblMYC1. Transcripts of HblMYC1 and HblMYC2 were most abundant in latex, relatively low in male flowers and nearly undetected in bark tissues and roots by real-time RT-PCR analysis. Regular tapping, mechanical wounding, and ethrel remarkably up-regulated HblMYC1 expression, but had little effect on the expression of HblMYC2 in laticifer cells. Successive tapping, however, significantly down-regulated the expression of HblMYC2 while up-regulating the expression of HblMYC1. The HblMYC2 expression took a mutual ebb and flow relationship with the HblMYC1 expression upon treatment with methyl jasmonate. Characterization of HblMYC1 and HblMYC2 will contribute to the understanding of jasmonate signaling in laticifiers, a kind of specialized tissue for natural rubber biosynthesis in Hevea brasiliensis. Topics: Acetates; Amino Acid Sequence; Base Sequence; Cyclopentanes; DNA, Complementary; DNA, Plant; Gene Expression Regulation, Plant; Helix-Loop-Helix Motifs; Hevea; Latex; Molecular Sequence Data; Organophosphorus Compounds; Oxylipins; Phylogeny; Plant Bark; Plant Growth Regulators; Plant Leaves; Plant Proteins; Plant Roots; Plant Shoots; Promoter Regions, Genetic; RNA, Plant; Sequence Alignment; Signal Transduction; Transcription Factors | 2011 |
Expression of ACO1, ERS1 and ERF1 genes in harvested bananas in relation to heat-induced defense against Colletotrichum musae.
The aim of this study was to investigate the connection between heat-induced ethylene signal changes and enhanced disease resistance. Heat enhanced ripening and elevated MaACO1 expression in naturally ripened bananas (NRB), while it delayed ripening and reduced MaACO1expression in the ethephon-treated bananas (ETB). However, in both cases, heat reduced lesion sizes infected by Colletotrichum musae. This indicates that heat-induced disease resistance in bananas was independent of ripening rate. The expression of MaERS1 gene was inhibited by heat treatment in both NRB and ETB, implying that heat as a physical signal could be sensed by banana fruits through the inhibition of ethylene receptor gene expression. The intensity of MaERF1 transcript signals was elevated in heated bananas, suggesting that the enhanced accumulation of MaERF1 transcript following heat treatment could play an important role in activation of the defense system. In ETB, inhibition of JA biosynthesis by application of IBU down-regulated the expression of MaERF and significantly weakened disease resistance, suggesting involvement of endogenous JA in induction of the gene expression, which was reconfirmed by the fact that exposure to exogenous MeJA following the combination of heat plus IBU treatment restored part of the gene expression. On the other hand, in NRB, application of IBU elevated level of MaERF1 expression at 24h and enhanced disease resistance, suggesting that, when banana was not exposed to ethephon, the expression of MaERF1 gene was not JA dependent, which was verified by the fact that MeJA application did not enhance MaERF1 gene expression. In conclusion, heat-induced disease resistance in harvested bananas could involve down-regulation of MaERS1 expression and up-regulation of MaERF1 expression and JA pathway could be involved in heat activation of the defense system in bananas exposed to ethephon. Topics: Acetates; Amino Acid Oxidoreductases; Colletotrichum; Cyclooxygenase Inhibitors; Cyclopentanes; Down-Regulation; Ethylenes; Fruit; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Plant; Genes, Plant; Hot Temperature; Ibuprofen; Musa; Organophosphorus Compounds; Oxylipins; Plant Diseases; Plant Growth Regulators; Plant Immunity; Plant Proteins; Random Allocation; Receptors, Cell Surface; Signal Transduction; Up-Regulation | 2011 |
Molecular characterization and expression analysis of cDNAs encoding four Rab and two Arf GTPases in the latex of Hevea brasiliensis.
In plants, Rab and Arf GTPases are key regulators of vesicle trafficking. To investigate whether these small GTPases (SG) play a role in the regulation of the regeneration of latex (the cytoplasm of the rubber-producing laticifer cell) in Hevea brasiliensis (Hevea hereafter), full-length cDNAs that encode four HbRab and two HbArf GTPases were cloned. The four HbRab proteins showed specific GTP-binding activity when expressed in Escherichia coli. Transcript expression of the six SG genes was investigated by real-time RT-PCR. All genes revealed to be expressed in each of the six Hevea tissues examined, but the expression patterns were different. Four genes, HbArf1, HbRab2, HbRab3 and HbRab4, displayed a preferential expression in latex. The expression of all genes was upregulated by the act of latex exploitation (tapping), and HbRab1 had the highest level of upregulation. Wounding markedly upregulated the expression of two SG genes (HbRab1 and HbArf2), and exogenous methyl jasmonate upregulated all six SG genes. Wounding might upregulate the expression of HbRab1 and HbArf2 through a jasmonic acid-mediated signaling pathway. None of the genes were markedly upregulated by Ethrel (an ethylene releaser and latex stimulator); instead, HbArf2 and HbRab4 were downregulated significantly after a 24 h treatment with Ethrel. This paper gives the first description of Rab and Arf GTPases in Hevea and provides clues for their involvement, HbRab1 in particular, in latex regeneration. Topics: Acetates; ADP-Ribosylation Factors; Amino Acid Sequence; Base Sequence; Cloning, Molecular; Consensus Sequence; Cyclopentanes; DNA, Complementary; Flowers; Gene Expression Regulation, Plant; Genes, Plant; Hevea; Latex; Molecular Sequence Data; Organophosphorus Compounds; Oxylipins; Phylogeny; Plant Growth Regulators; Plant Leaves; Plant Proteins; Plant Stems; Protein Structure, Tertiary; rab GTP-Binding Proteins; RNA, Plant; Seeds; Sequence Alignment; Sequence Analysis, DNA | 2011 |
Systemic induction of a Capsicum chinense nitrate reductase by the infection with Phytophthora capsici and defence phytohormones.
The mRNA differential display technique was used to identify genes from Habanero pepper (Capsicum chinense Jacq.) seedlings whose expression is modified systemically by infection with the oomycete Phytophthora capsici L. Experiments with different oligonucleotide primer combinations revealed that no single gene was synthesised de novo. Instead, the quantitative accumulation of multiple transcripts was found. From these transcripts, levels of a nitrate reductase (Capsicum chinense nitrate reductase, CcNR), which has a high percentage of identity with other Solanaceae NRs, showed a consistent increase a few hours after inoculation (hai) with P. capsici. Reverse northern blotting revealed the existence of basal levels of CcNR transcripts in different adult tissues; however, systemic levels rose dramatically after spraying seedlings with salicylic acid (SA) and ethephon (ET) but not with methyl jasmonate (MeJa). Both P. capsici and defence phytohormones (DP) also modified NR enzymatic activity (nitrite:NAD(+) oxidoreductase; EC 1.7.1.1) with similar kinetics. Because the application of DP induced and activated the CcNR differentially, it is possible that the activity of CcNR is related to a specific host defence response. Topics: Acetates; Capsicum; Cyclopentanes; Enzyme Activation; Gene Expression Regulation, Plant; Genes, Plant; Nitrate Reductase; Organophosphorus Compounds; Oxylipins; Phytophthora; Plant Diseases; Plant Growth Regulators; Plant Immunity; Plant Leaves; Plant Proteins; RNA, Plant; Salicylic Acid; Time Factors | 2011 |
Gummosis in grape hyacinth (Muscari armeniacum) bulbs: hormonal regulation and chemical composition of gums.
The purpose of this study was to investigate the hormonal regulation of gummosis in grape hyacinth (Muscari armeniacum) bulbs, focusing especially on the chemical composition of the gums. The application of ethephon (2-chloroethylphosphonic acid), an ethylene-releasing compound, at 1% and 2% (w/w) in lanolin as well as ethylene induced gummosis in the bulbs within several days. Methyl jasmonate (JA-Me, 0.1-2% in lanolin) alone had no effect on gummosis. However, simultaneous application of JA-Me and ethephon led to extreme stimulation of ethephon-induced gummosis. Ethephon-induced gummosis in the bulbs depended on the maturation stage of the bulbs, increasing from April to July, but decreasing from August to September. Regardless of the presence of JA-Me, the application of ethephon to the inflorescence axis of grape hyacinths did not induce gummosis. Gel permeation chromatography analysis revealed that gums were homogenous polysaccharides with an average molecular mass of ca. 8.3 kDa. Analysis of the sugar composition of the gums after hydrolysis revealed that the molar ratio of Rha:Ara:Gal:GalA:GlcA was 25:10:40:7:15. These results suggest that principal factors of gummosis as well as the chemical composition of gums differ between species of bulbous plants. Topics: Acetates; Chromatography, Ion Exchange; Cyclopentanes; Ethylenes; Hyacinthus; Molecular Weight; Organophosphorus Compounds; Oxylipins; Plant Growth Regulators; Plant Gums; Plant Roots; Seasons; Vitis | 2010 |
BnNHL18A shows a localization change by stress-inducing chemical treatments.
The two genes, named BnNHL18A and BnNHL18B, showing sequence homology with Arabidopsis NDR1/HIN1-like (NHL) genes, were isolated from cDNA library prepared with oilseed rape (Brassica napus) seedlings treated with NaCl. The transcript level of BnNHL18A was increased by sodium chloride, ethephon, hydrogen peroxide, methyl jasmonate, or salicylic acid treatment. The coding regions of BnNHL18A and BnNHL18B contain a sarcolipin (SLN)-like sequence. Analysis of the localization of smGFP fusion proteins showed that BnNHL18A is mainly localized to endoplasmic reticulum (ER). This result suggests that the SLN-like sequence plays a role in retaining proteins in ER membrane in plants. In response to NaCl, hydrogen peroxide, ethephon, and salicylic acid treatments, the protein localization of BnNHL18A was changed. Our findings suggest a common function of BnNHL18A in biotic and abiotic stresses, and demonstrate the presence of the shared mechanism of protein translocalization between the responses to plant pathogen and to osmotic stress. Topics: Acetates; Amino Acid Sequence; Arabidopsis Proteins; Brassica napus; Cyclopentanes; Endoplasmic Reticulum; Gene Expression Regulation, Plant; Gene Library; Hydrogen Peroxide; Molecular Sequence Data; Muscle Proteins; Organophosphorus Compounds; Osmotic Pressure; Oxylipins; Phylogeny; Plant Proteins; Protein Transport; Proteolipids; Salicylic Acid; Sodium Chloride; Transcription Factors | 2006 |
Salicylic acid, ethephon, and methyl jasmonate enhance ester regeneration in 1-MCP-treated apple fruit after long-term cold storage.
Volatile esters, primarily synthesized in peel tissues, are major aromatic components of apple fruits [Malus sylvestris (L.) Mill. var. domestica (Borkh.) Mansf.]. The use of cold storage combined with 1-methylcyclopropene (1-MCP) treatment prolongs the life of apples but represses the regeneration of esters during poststorage ripening. In this study, the regeneration of total esters was significantly increased in apple fruits treated with salicylic acid (SA) and Ethephon (ETH) that had been treated once or twice with 1-MCP. However, methyl jasmonate (MeJA) treatment resulted in regeneration of total esters after a single 1-MCP treatment. To determine the mechanism by which SA, ETH, and MeJA regulate ester regeneration, the apple alcohol acyltransferase gene (MdAAT2) was investigated at the mRNA, protein, and enzyme activity levels. Genes associated with ethylene perception were also investigated by RT-PCR. The results suggest that MdAAT2 controls ester regeneration and that MdETR1 plays a key role in ethylene perception and regulation of downstream MdAAT2 gene expression during poststorage. Ester compounds and concentrations differed in peels treated with different signal molecules, indicating that regulation of the pathway upstream of straight-chain ester biosynthesis depended on the regulation of lipoxygenase (LOX) and alcohol dehydrogenase (ADH) activity by SA, ETH, and MeJA during poststorage ripening. Topics: Acetates; Acyltransferases; Cold Temperature; Cyclopentanes; Cyclopropanes; Esters; Ethylenes; Food Preservation; Fruit; Malus; Organophosphorus Compounds; Oxylipins; Plant Growth Regulators; Plant Proteins; Salicylic Acid; Volatilization | 2006 |
Enhanced ginsenoside productivity by combination of ethephon and methyl jasmoante in ginseng (Panax ginseng C.A. Meyer) adventitious root cultures.
Ethephon at 50 microM enhanced both root growth and ginsenoside accumulation in ginseng (Panax ginseng C.A. Meyer) adventitious root cultures, but at 100 microM it inhibited only ginsenoside accumulation. Ginsenoside productivity with 50 microM ethephon was the highest at 1.7 mg l(-1) d(-1) after 8 days of elicitation. However, elicitation with 50 microM ethephon and 100 microM methyl jasmonate (MJ) improved productivity (6.3 mg l(-1) d(-1)) whereas elicitation with 100 microM MJ alone gave only 2.9 mg l(-1) d(-1). Topics: Acetates; Cyclopentanes; Ginsenosides; Organophosphorus Compounds; Oxylipins; Panax; Plant Extracts; Plant Growth Regulators; Plant Roots | 2006 |
CaWRKY2, a chili pepper transcription factor, is rapidly induced by incompatible plant pathogens.
WRKY family proteins are a class of plant-specific transcription factors involved in stress response signaling pathways. In this study a gene encoding a putative WRKY protein was isolated from a pepper EST database (http://genepool.kribb.re.kr). The cDNA, named Capsicum annuum WRKY2 (CaWRKY2), encodes a putative polypeptide of 548 amino acids, containing two WRKY domains with zinc finger motifs and two potential nuclear localization signals. Northern blot analyses showed that CaWRKY2 mRNA was preferentially induced during incompatible interactions of pepper plants with PMMoV, Pseudomonas syringae pv. syringae 61, and Xanthomonas axonopodis pv. vesicatoria race 3. Furthermore, CaWRKY2 transcripts were strongly induced by wounding and ethephon treatment, whereas only moderate expression was detected following treatment with salicylic acid and jasmonic acid. CaWRKY2 was translocated to the nucleus when a CaWRKY2-smGFP fusion construct was expressed in onion epidermal cells. CaWRKY2 also had transcriptional activation activity in yeast. Taken together our data suggest that CaWRKY2 is a pathogen-inducible transcription factor that may have a role in early defense responses to biotic and abiotic stresses. Topics: Acetates; Amino Acid Sequence; Capsicum; Cell Nucleus; Cyclopentanes; Genes, Plant; Genome, Plant; Molecular Sequence Data; Organophosphorus Compounds; Oxylipins; Plant Diseases; Plant Proteins; Pseudomonas syringae; Saccharomyces cerevisiae; Salicylic Acid; Sequence Alignment; Transcription Factors; Transcriptional Activation; Xanthomonas; Xanthomonas vesicatoria | 2006 |
Jasmonates are essential factors inducing gummosis in tulips: mode of action of jasmonates focusing on sugar metabolism.
The purpose of this study was to know the mechanism of jasmonates to induce gummosis in tulip (Tulipa gesneriana L. cv. Apeldoorn) shoots, especially on the focus of sugar metabolism. Gummosis in the first internode of tulip plants was induced by the application of methyl jasmonate (JA-Me, 1% w/w in lanolin) and jasmonic acid (JA, 1% w/w in lanolin) 5 days after application and strongly stimulated by the simultaneous application of ethylene-releasing compound, ethephon (2-chloroethylphosphonic acid, 1% w/w in lanolin), although ethephon alone had little effect. JA-Me stimulated ethylene production of the first internodes of tulips, ethylene production increasing up to more than 5 times at day 1 and day 3 after the application. On the other hand, application of ethephon did not increase endogenous levels of jasmonates in tulip stems. Analysis of composition of tulip gums revealed that they were consisted of glucuronoarabinoxylan with an average molecular weight of ca. 700 kDa. JA-Me strongly decreased the total amount of soluble sugars in tulip stems even in 1 day after application, being ca. 50% of initial values 5 days after application, but ethephon did not. However, both JA-Me and ethephon had almost no effect on the neutral sugar compositions of soluble sugars mainly consisting of glucose, mannose and xylose in ratio of 20:2:1 and traces of arabinose. Both JA-Me and ethephon applied exogenously stimulated senescence of tulip shoots shown by the loss of chlorophyll. These results strongly suggest that the essential factor of gummosis in tulips is jasmonates affecting the sugar metabolism in tulip shoots. The mode of action of jasmonates to induce gummosis of tulip shoots is discussed in relation to ethylene production, sugar metabolism and senescence. Topics: Acetates; Carbohydrate Metabolism; Cell Wall; Cyclopentanes; Ethylenes; Organophosphorus Compounds; Oxylipins; Plant Stems; Signal Transduction; Tulipa | 2005 |
Identification of a CaRAV1 possessing an AP2/ERF and B3 DNA-binding domain from pepper leaves infected with Xanthomonas axonopodis pv. glycines 8ra by differential display.
We isolated a cDNA clone, CaRAV1, which exhibited significant similarity to those of Arabidopsis RAV proteins containing AP2/ERF and B3-like DNA-binding domains. CaRAV1 expression was rapidly and specifically induced in both host and non-host resistant responses against bacterial pathogens in the chili pepper plant. CaRAV1 also strongly increased following salicylic acid and ethephon treatments, whereas methyl-jasmonate only had mild effects. Furthermore, CaRAV1 transcript levels were also investigated in response to ABA and abiotic stress. No significant CaRAV1 expression was evident following ABA, mannitol, or cold treatments. These observations collectively provide initial evidence that the pepper RAV transcription factor homolog may function in plant defense responses. Topics: Acetates; Amino Acid Sequence; Anti-Infective Agents; Arabidopsis Proteins; Capsicum; Cyclopentanes; DNA-Binding Proteins; DNA, Complementary; DNA, Plant; Freezing; Gene Expression Profiling; Gene Expression Regulation, Plant; Glycine; Homeodomain Proteins; Mannitol; Molecular Sequence Data; Nuclear Proteins; Organophosphorus Compounds; Oxylipins; Plant Growth Regulators; Plant Leaves; Plant Proteins; Salicylic Acid; Sequence Homology, Amino Acid; Xanthomonas | 2005 |
A Colletotrichum gloeosporioides-induced esterase gene of nonclimacteric pepper (Capsicum annuum) fruit during ripening plays a role in resistance against fungal infection.
Ripe fruits of pepper (Capsicum annuum) are resistant to the anthracnose fungus, Colletotrichum gloeosporioides, whereas unripe-mature fruits are susceptible. A pepper esterase gene (PepEST) that is highly expressed during an incompatible interaction between the ripe fruit of pepper and C. gloeosporioides was previously cloned. Deduced amino acid sequence of PepEST cDNA showed homology to both esterases and lipases, and contained -HGGGF- and -GXSXG- motifs and a catalytic triad. Inhibition of PepEST activity by a specific inhibitor of serine hydrolase demonstrated that a serine residue is critical for the enzyme activity. Expression of PepEST gene was fruit-specific in response to C. gloeosporioides inoculation, and up-regulated by wounding or jasmonic acid treatment during ripening. PepEST mRNA and protein was differentially accumulated in ripe vs. unripe fruit from 24 h after inoculation when C. gloeosporioides is invading into fruits. Immunochemical examination revealed that PepEST accumulation was localized in epidermal and cortical cell layers in infected ripe fruit, but rarely even in epidermal cells in infected unripe one. Over-expression of PepEST in transgenic Arabidopsis plants caused restriction of Alternaria brassicicola colonization by inhibition of spore production, resulting in enhanced resistance against A.brassicicola. These results suggest that PepEST is involved in the resistance of ripe fruit against C.gloeosporioides infection. Topics: Abscisic Acid; Acetates; Alternaria; Amino Acid Sequence; Arabidopsis; Capsicum; Colletotrichum; Cyclopentanes; Electrophoresis, Polyacrylamide Gel; Esterases; Fruit; Gene Expression Regulation, Developmental; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Plant; Immunity, Innate; Molecular Sequence Data; Organophosphorus Compounds; Oxylipins; Plant Diseases; Plant Growth Regulators; Plants, Genetically Modified; Recombinant Proteins; RNA, Messenger; Salicylic Acid; Sequence Alignment; Sequence Homology, Amino Acid; Stress, Mechanical; Time Factors | 2005 |
Chitinase induced by jasmonic acid, methyl jasmonate, ethylene and protein phosphatase inhibitors in rice.
Chitinase is a pathogenesis-related protein that hydrolyzes chitin, a major component of fungal cell walls. Two-week-old rice seedling leaf, leaf sheath and root tissues responded to an exogenous treatment by jasmonic acid (JA) with induction of the chitinases as determined by immunoblot analysis using an anti-endochitinase antibody. Induced accumulation of these chitinases was observed within 24 to 48 h in the leaf sheaths, leaves and roots. Besides, ethylene generator ethephon and abiotic stressor copper could also induce chitinases accumulation among various plant hormones and stress agents examined. Cycloheximide effectively blocked their accumulation by JA, suggesting that de novo protein synthesis is required. Partial blockage of the induced accumulation of chitinases by NADPH oxidase inhibitor and free radical scavengers suggested involvement of reactive oxygen species. Moreover, induced accumulation of these chitinases also by methyl jasmonate and certain protein phosphatase inhibitors indicated their potential importance and wider role in rice seedlings. Topics: Acetates; Chitinases; Cycloheximide; Cyclopentanes; Enzyme Inhibitors; Ethylenes; Onium Compounds; Organophosphorus Compounds; Oryza; Oxylipins; Phosphoprotein Phosphatases; Plant Growth Regulators; Plant Structures; Reactive Oxygen Species | 2004 |
Overexpression of the AP2/EREBP transcription factor OPBP1 enhances disease resistance and salt tolerance in tobacco.
Osmotin promoter binding protein 1 (OPBP1), an AP2/EREBP-like transcription factor of tobacco (Nicotiana tabacum), was isolated using a yeast one-hybrid system. RNA gel blot analysis indicated that expression of the OPBP1 gene was induced by elicitor cryptogein, NaCl, ethephon, methyl jasmonate, as well as cycloheximide. Transient expression analysis using an OPBP1-eGFP fusion gene in onion epidermal cells revealed that the OPBP1 protein was targeted to the nuclear. Further, electrophoretic mobility shift assays demonstrated that the recombinant OPBP1 protein could bind to an oligonucleotide containing the GCC-box cis element. Transgenic tobacco plants with an over expression of the OPBP1 gene accumulated high levels of PR-1a and PR-5d genes and exhibited enhanced resistance to infection by Pseudomonas syringae pv tabaci and Phytophthora parasitica var nicotianae pathogens. They also exhibited increased tolerance to salt stress. These results suggest that OPBP1 might be a transcriptional regulator capable of regulating expression in sets of stress-related genes. Topics: Acetates; Adaptation, Physiological; Algal Proteins; Base Sequence; Binding Sites; Binding, Competitive; Cell Nucleus; Cycloheximide; Cyclopentanes; Fungal Proteins; Gene Expression Regulation, Plant; Green Fluorescent Proteins; Immunity, Innate; Mutation; Nicotiana; Oligonucleotides; Organophosphorus Compounds; Oxylipins; Phylogeny; Phytophthora; Plant Diseases; Plant Proteins; Protein Binding; Pseudomonas syringae; Recombinant Fusion Proteins; Sodium Chloride; Transcription Factors | 2004 |
A leaf-specific 27 kDa protein of potato Kunitz-type proteinase inhibitor is induced in response to abscisic acid, ethylene, methyl jasmonate, and water deficit.
The 22 kDa Kunitz-type potato proteinase inhibitor (22 kDa KPPI) was induced in tubers. However, the 27 kDa protein, which is immunologically related to the 22 kDa KPPI, was induced in leaves by wounding, hormones, and environmental stresses. The leaf-specific 27 kDa protein was induced in leaves that were treated with exogenous abscisic acid (ABA), ethephon, methyl jasmonate (MeJA), and water deficit. These results indicate that the 27 kDa protein in leaves could function as a defense protein against mechanical damages by herbivorous animals and abiotic environmental stresses that could induce plant hormones. Topics: Abscisic Acid; Acetates; Cyclopentanes; Ethylenes; Molecular Weight; Organophosphorus Compounds; Oxylipins; Peptides; Plant Growth Regulators; Plant Leaves; Plant Proteins; Solanum tuberosum; Trypsin Inhibitors; Water | 2002 |
Biochemical, molecular and structural analysis of multiple thaumatin-like proteins from the elderberry tree (Sambucus nigra L.).
Thaumatin-like proteins (TLPs) were isolated and characterized from fruits and leaves of elderberry (Sambucus nigra) and their corresponding genes cloned. In addition, the developmental regulation and induction of the different TLPs was followed in some detail. Ripening berries accumulated a fruit-specific TLP during the final stages of maturation. This fruit-specific TLP had no antifungal activity and was devoid of beta-glucanase activity. Leaves constitutively expressed a TLP that closely resembled the fruit-specific homologue. Treatment with jasmonate methyl ester induced two additional TLPs in leaves but did not induce or enhance the expression of TLPs in immature berries. In contrast to jasmonate methyl ester, both ethephon and garlic extract induced the expression of a TLP in unripe berries that normally do not express any TLP. Sequence analysis and molecular modeling indicated that all elderberry thaumatin-like proteins share a high sequence similarity with group-5 pathogenesis-related proteins. However, the proteins encoded by the different sequences differed from each other in isoelectric point and the distribution of the charges on the surface of the molecule. Topics: Acetates; Amino Acid Sequence; Anti-Infective Agents; Cloning, Molecular; Cyclopentanes; DNA, Complementary; Fruit; Fungi; Garlic; Gene Expression Regulation, Plant; Genes, Plant; Glucan Endo-1,3-beta-D-Glucosidase; Models, Molecular; Molecular Sequence Data; Organophosphorus Compounds; Oxylipins; Plant Extracts; Plant Proteins; Sambucus nigra; Sequence Homology, Amino Acid | 2002 |
Effect of salicylic acid, methyl jasmonate, ethephon and cantharidin on anthraquinone production by Rubia cordifolia callus cultures transformed with the rolB and rolC genes.
It has been suggested that the rol genes of Agrobacterium rhizogenes could play an essential role in the activation of secondary metabolite production in plant transformed cultures. This study investigated whether the content of anthraquinone phytoalexins was changed in callus cultures of Rubia cordifolia transgenic for the 35S-rolB and 35S-rolC genes in comparison with a non-transformed callus culture. The anthraquinone content was shown to be significantly increased in transgenic cultures, thus providing further evidence that the rol-gene transformation can be used for the activation of secondary metabolism in plant cells. Methyl jasmonate and salicylic acid strongly increased anthraquinone accumulation in both transgenic and non-transgenic R. cordifolia calluses, whereas ethephon did not. A treatment of the cultures by cantharidin, the protein phosphatase 2A inhibitor, resulted in massive induction of anthraquinone accumulation in the transgenic cultures only. We suggest the involvement of a cantharidin-sensitive protein phosphorylation mechanism in anthraquinone biosynthesis in transgenic cultures. Topics: Acetates; Anthraquinones; beta-Glucosidase; Cantharidin; Cyclopentanes; Enzyme Inhibitors; Gene Expression; Gene Expression Regulation; Genes, Bacterial; Oncogene Proteins; Oncogenes; Organophosphorus Compounds; Oxylipins; Plant Growth Regulators; Plants, Genetically Modified; Rhizobium; Rubiaceae; Salicylic Acid; Sensitivity and Specificity | 2002 |
A hot pepper cDNA encoding a pathogenesis-related protein 4 is induced during the resistance response to tobacco mosaic virus.
Hot pepper (Capsicum annuum) plants exhibit a hypersensitive response (HR) against infection by many tobamoviruses. A clone (CaPR-4) encoding a putative pathogenesis-related protein 4 was isolated by differential screening of a cDNA library prepared from resistant pepper plant leaves inoculated with tobacco mosaic virus (TMV) pathotype P0. The predicted amino acid sequence of CaPR-4 is very similar to those of other plant PR-4s. Southern blot analysis showed that small gene families of PR-4-related sequences were present in the pepper genome. Hot pepper cultivar Bugang, resistant to TMV-P0 and susceptible to TMV-P1.2, induced CaPR-4 expression by pathotype P0 inoculation in inoculated and systemic leaves, but not by pathotype P1.2. Effects of exogenously applied abiotic elicitors upon the CaPR-4 expression were also examined. The expression of the CaPR-4 gene was stimulated by methyl jasmonate (MeJA), ethephon and wounding treatment. However, application of salicylic acid (SA) did not trigger the expression. Evidence is emerging that jasmonic acid and ethylene play key roles in the SA-independent pathways of plant-pathogen interaction. Taken together, these results suggest that the CaPR-4 gene is one of the defense-related genes conferring resistance on pepper plants by the SA-independent pathway and the cross-talk between signaling compounds, jasmonic acid and ethylene could have a great regulatory potential in a plant's defense against TMV. Topics: Acetates; Base Sequence; Capsicum; Cloning, Molecular; Cyclopentanes; DNA, Complementary; Gene Expression Regulation, Plant; Immunity, Innate; Molecular Sequence Data; Organophosphorus Compounds; Oxylipins; Plant Growth Regulators; Plant Proteins; Plants, Medicinal; RNA, Messenger; Sequence Homology, Amino Acid; Tobacco Mosaic Virus | 2001 |
A pathogen-induced chitin-binding protein gene from pepper: its isolation and differential expression in pepper tissues treated with pathogens, ethephon, methyl jasmonate or wounding.
A chitin-binding protein (CBP) cDNA (CACBP1) was isolated from a cDNA library of pepper (Capsicum annuum L.) leaves infected with Xanthomonas campestris pv. vesicatoria. The deduced amino acid sequence of the CACBP1 gene which has chitin-binding domain and hinge region shares a high level of identity with CBP sequences from tomato, potato and tobacco. The CACBP1 gene was organ-specifically regulated in pepper plants, and differentially induced during the compatible and incompatible interactions of pepper with X. campestris pv. vesicatoria or Phytophthora capsici. Expression of the CACBP1 gene was rapidly induced in the incompatible interactions upon pathogen infection. Transcripts of the CACBP1 gene was highly inducible in the leaves of matured pepper plants by Colletotrichum coccodes infection. In situ hybridization results showed that CACBP1 mRNA was expressed in the phloem area of vascular bundles in C. coccodes-infected leaf tissues. The pathogen-inducible CACBP1 gene was also strongly induced and accumulated in pepper leaves by ethephon, methyl jasmonate or wounding. These data suggest that ethylene and jasmonate may act as signal molecules in the signal transduction pathways of the CBP gene induction during the pepper defense- or pathogenesis-related plant responses. Topics: Acetates; Amino Acid Sequence; Capsicum; Carrier Proteins; Chitin; Colletotrichum; Cyclopentanes; Gene Expression Regulation, Plant; Molecular Sequence Data; Organophosphorus Compounds; Oxylipins; Phytophthora; Plant Diseases; Plant Leaves; Sequence Homology, Amino Acid; Signal Transduction; Stress, Mechanical; Transcriptional Activation; Xanthomonas campestris | 2001 |
Isolation, partial sequencing, and expression of pathogenesis-related cDNA genes from pepper leaves infected by Xanthomonas campestris pv. vesicatoria.
Specific cDNAs showing differential expression in bacteria-infected pepper leaves as opposed to healthy leaves were isolated from a pepper cDNA library from hypersensitive response (HR) lesions of leaves infected with an avirulent strain of Xanthomonas campestris pv. vesicatoria. Among a total of 282 cDNA clones tested, 36 individual cDNA genes (13%) hybridized strongly or differentially to the cDNA probes from bacteria-infected leaves. Ten Capsicum Annuum-Induced (CAI) genes encoding putative thionin, lipid transfer protein I and II, osmotin (PR-5), class I chitinase, beta-1,3-glucanase, SAR 8.2, stellacyanin, leucine-rich repeat protein, and auxin-repressed protein were identified. Two CAI genes showed little or no sequence homology to the previously sequenced plant genes. Transcripts of the CAI genes were strongly or preferentially induced in pepper tissues by infection with X. campestris pv. vesicatoria or Phytophthora capsici, and by abiotic elicitor treatment. In particular, most of the CAI genes were strongly induced in pepper tissues by ethephon and methyl jasmonate. Topics: Acetates; Amino Acid Sequence; Blotting, Northern; Capsicum; Cyclopentanes; Gene Library; Molecular Sequence Data; Organophosphorus Compounds; Oxylipins; Phytophthora; Plant Growth Regulators; Plant Leaves; Plants, Medicinal; RNA, Plant; Sequence Homology, Amino Acid; Xanthomonas campestris | 2000 |
An HR-induced tobacco peroxidase gene is responsive to spermine, but not to salicylate, methyl jasmonate, and ethephon.
In Tobacco mosaic virus (TMV)-infected tobacco plants carrying the N resistance gene, a hypersensitive reaction or response (HR) occurs to enclose the virus in the infected tissue. Although a contribution of peroxidases to the resistance has been proposed, no evidence has been presented that tobacco peroxidase genes respond to HR. Here, we describe the HR-induced expression of a tobacco peroxidase gene (tpoxC1) whose induction kinetics were slightly different from those of acidic and basic tobacco pathogenesis-related (PR) protein genes. Interestingly, tpoxC1 was insensitive to the inducers of PR genes such as salicylic acid, methyl jasmonate, and ethephon. Spermine activated tpoxC1 gene expression at a low level and both acidic and basic PR gene expression at a considerably higher level. These results indicate that the induced expression of tpoxC1 is regulated differently from that of classical tobacco PR genes in the N gene-mediated self-defense system in tobacco plants. Topics: Acetates; Cyclopentanes; Genes, Plant; Nicotiana; Organophosphorus Compounds; Oxylipins; Peroxidases; Plant Growth Regulators; Plants, Toxic; Salicylic Acid; Spermine; Tobacco Mosaic Virus | 2000 |
Herbivore-induced ethylene suppresses a direct defense but not a putative indirect defense against an adapted herbivore.
Herbivory induces both direct and indirect defenses in plants; however, some combinations of these defenses may not be compatible. The jasmonate signal cascade activated both direct (nicotine accumulations) and indirect (mono- and sesquiterpene emissions) whole-plant defense responses in the native tobacco Nicotiana attenuata Torr. Ex Wats. Nicotine accumulations were proportional to the amount of leaf wounding and the resulting increases in jasmonic acid (JA) concentrations. However, when larvae of the nicotine-tolerant herbivore, Manduca sexta, fed on plants or their oral secretions were applied to leaf punctures, the normal wound response was dramatically altered, as evidenced by large (4- to 10-fold) increases in the release of (i) volatile terpenoids and (ii) ethylene, (iii) increased (4- to 30-fold) accumulations of endogenous JA pools, but (iv) decreased or unchanged nicotine accumulations. The ethylene release, which was insensitive to inhibitors of induced JA accumulation, was sufficient to account for the attenuated nicotine response. Applications of ethylene and ethephon suppressed the induced nicotine response and pre-treatment of plants with a competitive inhibitor of ethylene receptors, 1-methylcyclopropene, restored the full nicotine response. This ethylene burst, however, did not inhibit the release of volatile terpenoids. Because parasitoids of Manduca larvae are sensitive to the dietary intake of nicotine by their hosts, this ethylene-mediated switching from direct to a putative indirect defense may represent an adaptive tailoring of a plant's defense response. Topics: Acetates; Analysis of Variance; Animals; Cyclopentanes; Cyclopropanes; Ethylenes; Indoleacetic Acids; Manduca; Nicotiana; Nicotine; Organophosphorus Compounds; Oxylipins; Plant Growth Regulators; Plant Leaves; Plant Roots; Plants, Toxic; Salicylic Acid | 2000 |
Wound-induced expression of a tobacco peroxidase is not enhanced by ethephon and suppressed by methyl jasmonate and coronatine.
In tobacco plants, wounding induces production of a set of defense-related proteins such as basic pathogenesis-related (PR) proteins and proteinase inhibitors (PIs) via the jasmonate/ethylene pathway. Although class III plant peroxidase (POX) is also wound-inducible, the regulatory mechanism for its wound-induced expression is not fully understood. Here, we describe that a tobacco POX gene (tpoxN1), which is constitutively expressed in roots, is induced locally 30 min after wounding and then systemically in tobacco plants. Infection of necrotizing virus also induced tpoxN1 gene. The wound-induced expression was not enhanced by known wound-signal compounds such as methyl jasmonate (MeJA) and ethephon in contrast to other wound-inducible genes such as basic PR-1 and PI-II genes. And treatment with MeJA and coronatine, biological analogs of jasmonate, rather suppressed the tpoxN1 expression. Salicylic acid, an antagonist of jasmonate-based wound signaling, did not suppress the wound-induced expression of tpoxN1. Only spermine, which is reported as an endogenous inducer for acidic PR genes in tobacco mosaic virus-infected tobacco leaves, could induce tpoxN1 gene expression. These results suggest that wound-induced expression of the tpoxN1 gene is regulated differently from that of the basic PR and PI-II genes. Topics: Acetates; Amino Acids; Cyclopentanes; Enzyme Induction; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Plant; Indenes; Nicotiana; Organophosphorus Compounds; Oxylipins; Peroxidase; Plant Growth Regulators; Plants, Toxic; Tobacco Mosaic Virus | 2000 |
Secreted proteins of tobacco cultured BY2 cells: identification of a new member of pathogenesis-related proteins.
Cultured cells of tobacco BY2 secrete more than 100 proteins into culture medium. Six major proteins were purified, and partial protein sequences were determined. Five of them were found to be similar to an ascorbic acid oxidase, three peroxidase isozymes and a beta-1,3-exoglucanase, respectively. A cDNA clone encoding the remaining polypeptide, whose amino acid sequence showed no similarity with earlier reported proteins, was isolated. It encoded a putative 27 kDa protein of 242 amino acids with resemblance to WCI-5, a wheat protein induced by benzo(1,2,3)thiadiazole-7-carbothioic acid S-methyl ester (BTH) which activates genes involved in systemic acquired resistance. Transcripts of this clone accumulated upon tobacco mosaic virus infection, mechanical wounding and drought treatment, an induction profile that satisfies the definition of pathogenesis-related (PR) proteins by van Loon et al. (Plant Mol. Biol. Rep. 12 (1994) 245). No similar PR proteins have so far been reported, and therefore our newly designated NtPRp27 points to the existence of a novel PR protein family in tobacco plants. Topics: Abscisic Acid; Acetates; Amino Acid Sequence; Base Sequence; Blotting, Northern; Cells, Cultured; Culture Media, Conditioned; Cyclopentanes; DNA, Complementary; Electrophoresis, Gel, Two-Dimensional; Electrophoresis, Polyacrylamide Gel; Gene Expression Regulation, Plant; Molecular Sequence Data; Nicotiana; Organophosphorus Compounds; Oxylipins; Plant Growth Regulators; Plant Leaves; Plant Proteins; Plants, Toxic; RNA, Plant; Salicylic Acid; Sequence Analysis, DNA; Sequence Analysis, Protein; Sequence Homology, Amino Acid; Tissue Distribution; Water | 2000 |
Isolation and characterization of a dehydrin gene from white spruce induced upon wounding, drought and cold stresses.
A cDNA clone encoding a dehydrin gene was isolated from a cDNA library prepared from white spruce (Picea glauca) needle mRNAs. The cDNA, designated PgDhn1, is 1159 nucleotides long and has an open reading frame of 735 bp with a deduced amino acid sequence of 245 residues. The PgDhn1 amino acid sequence is highly hydrophilic and possesses four conserved repeats of the characterized lysine-rich K-segment (EKKGIMD-KIKEKLPG), and an 8-serine residue stretch prior to the first lysine-rich repeat that is common to many dehydrins. The DEYGNP conserved motif is, however, absent in the PgDhn1 sequence. In unstressed plants, the highest level of transcripts was detected in stem tissue and not fully expanded vegetative buds. PgDhn1 expression was also clearly detected in reproductive buds, at various stages of development. The mRNAs corresponding to PgDhn1 cDNA were induced upon wounding and by jasmonic acid (JA) and methyl jasmonate (MeJa) treatments. Upon drought stress, increased transcript accumulation was observed in needle tissue reaching a maximum level 48 h after treatment. Treatments of seedlings with abscisic acid or ethephon also resulted in high levels of transcript accumulation in needle tissue. Finally, cold induction of PgDhn1 transcripts was also detected as early as 8 h after treatment. Topics: Abscisic Acid; Acetates; Cold Temperature; Cyclopentanes; DNA, Complementary; Gene Expression Regulation, Developmental; Gene Expression Regulation, Plant; Molecular Sequence Data; Organophosphorus Compounds; Oxylipins; Plant Growth Regulators; Plant Proteins; RNA, Plant; Sequence Analysis, DNA; Stress, Mechanical; Transcription, Genetic; Trees; Water | 2000 |
Molecular cloning and characterization of a new basic peroxidase cDNA from soybean hypocotyls infected with Phytophthora sojae f.sp. glycines.
Differential display techniques were used to isolate cDNA clones corresponding to genes which were expressed in soybean hypocotyls by Phytophthora sojae f.sp. glycines infection. With a partial cDNA clone C20CI4 from the differential display PCR as a probe, a new basic peroxidase cDNA clone, designated GMIPER1, was isolated from a cDNA library of soybean hypocotyls infected with P. sojae f.sp. glycines. Sequence analysis revealed that the peroxidase clone encodes a mature protein of 35,813 Da with a putative signal peptide of 27 amino acids in its N-terminus. The amino acid sequence of the soybean peroxidase GMIPER1 is between 54-75% identical to other plant peroxidases including a soybean seed coat peroxidase. Southern blot analysis indicated that multiple copies of sequences related to GMIPER1 exist in the soybean genome. The mRNAs corresponding to the GMIPER1 cDNA accumulated predominantly in the soybean hypocotyls infected with the incompatible race of P. sojae f.sp. glycines, but were expressed at low levels in the compatible interaction. Soybean GMIPER1 mRNAs were not expressed in hypocotyls, leaves, stems, and roots of soybean seedlings. However, treatments with ethephon, salicylic acid or methyl jasmonate induced the accumulation of the GMIPER1 mRNAs in the different organs of soybean. These results suggest that the GMIPER1 gene encoding a putative pathogen-induced peroxidase may play an important role in induced resistance of soybean to P. sojae f.sp. glycines and in response to various external stresses. Topics: Acetates; Amino Acid Sequence; Anti-Infective Agents; Base Sequence; Blotting, Southern; Cloning, Molecular; Cyclopentanes; DNA, Complementary; DNA, Plant; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Plant; Gene Library; Genome, Plant; Glycine max; Hypocotyl; Molecular Sequence Data; Organophosphorus Compounds; Oxylipins; Peroxidase; Phytophthora; Plant Growth Regulators; Plant Leaves; Plant Stems; Plants; RNA, Messenger; Salicylic Acid; Sequence Analysis, DNA; Sequence Homology, Amino Acid; Tissue Distribution | 1998 |