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Sample records for abscisic acid treatment

  1. The regulatory network of ThbZIP1 in response to abscisic acid treatment

    Directory of Open Access Journals (Sweden)

    Xiaoyu eJi

    2015-02-01

    Full Text Available Previously, a bZIP transcription factor from Tamarix hispida, ThbZIP1, was characterized: plants overexpressing ThbZIP1 displayed improved salt stress tolerance but were sensitive to abscisic acid (ABA. In the current study, we further characterized the regulatory network of ThbZIP1 and the mechanism of ABA sensitivity mediated by ThbZIP1. An ABF transcription factor from T. hispida, ThABF1, directly regulates the expression of ThbZIP1. Microarray analysis identified 1,662 and 1,609 genes that were respectively significantly upregulated or downregulated by ThbZIP1 when exposed to ABA. GO analysis showed that the processes including response to stimulus, catalytic activity, binding function, and metabolic process were highly altered in ThbZIP1 expressing plants exposed to ABA. The gene expression in ThbZIP1 transformed plants were compared between exposed to ABA and salt on the genome scale. Genes differentially regulated by both salt and ABA treatment only accounted for 9.75% of total differentially regulated genes. GO analysis showed that structural molecule activity, organelle part, membrane-enclosed lumen, reproduction and reproductive process are enhanced by ABA but inhibited by salt stress. Conversely, immune system and multi-organism process were improved by salt but inhibited by ABA. Transcription regulator activity, enzyme regulator activity and developmental process were significantly altered by ABA but were not affected by salt stress. Our study provides insights into how ThbZIP1 mediates ABA and salt stress response at the molecular level.

  2. Relationship between abscisic acid (ABA) concentration and some ...

    African Journals Online (AJOL)

    saeed

    2011-11-16

    Nov 16, 2011 ... This work investigated the effects of endogenous abscisic acid (ABA) and physiologic parameters related to yield in two ... levels of endogenous ABA contribute to reduced grain growth. Key words: Abscisic acid, ..... Craterostigma plantagineum displays no defined three dimensional structure in its native ...

  3. Interactions between ethylene, abscisic acid and cytokinin during ...

    Indian Academy of Sciences (India)

    Interactions between ethylene, abscisic acid and cytokinin during germination and seedling establishment in Arabidopsis. VEERAPUTHIRAN SUBBIAH and KARINGU JANARDHAN REDDY. J. Biosci. 35(3), September 2010, 451–459 © Indian Academy of Sciences. Supplementary figure. Supplementary figure 1.

  4. Cis-trans photoisomerization of abscisic acid

    International Nuclear Information System (INIS)

    Brabham, D.E.; Biggs, R.H.

    1981-01-01

    An important regulator of numerous physiological processes in higher plants is abscisic acid (ABA), which is photoisomerized from the more biologically active cis isomer to the nearly inactive trans isomer by natural sunlight. It is possible that this photoisomerization is a UV control mechanism in functions regulated by ABA. The quantum yields of both the cis to trans and trans to cis photoisomerizations were measured under various conditions of pH and oxygen concentration at room temperature. The yield for photoisomerization of cis-ABA ranged from 0.25 at pH 3.0 to 0.11 at pH 7.0. Oxygen partially quenched the process. The quantum yield varied only slightly with wavelength. The quantum yield of photolysis of cis-ABA was reported for pH 3.0 as 0.06. This yield also varied slightly with wavelength and was relatively insensitive to oxygen. This relatively high yield explains the loss of potency of ABA during UV irradiation. Phosphorescence of cis- and trans-ABA was observed in methanol at 77 K. Onset of the emission was at 350 nm. The emission spectra were the same for both isomers. From these results a mechanism of UV action on plants based on the photoisomerization of the inactive trans-ABA to the biologically active cis isomer is proposed. (author)

  5. GENETIC ANALYSIS OF ABSCISIC ACID BIOSYNTHESIS

    Energy Technology Data Exchange (ETDEWEB)

    MCCARTY D R

    2012-01-10

    The carotenoid cleavage dioxygenases (CCD) catalyze synthesis of a variety of apo-carotenoid secondary metabolites in plants, animals and bacteria. In plants, the reaction catalyzed by the 11, 12, 9-cis-epoxy carotenoid dioxygenase (NCED) is the first committed and key regulated step in synthesis of the plant hormone, abscisic acid (ABA). ABA is a key regulator of plant stress responses and has critical functions in normal root and seed development. The molecular mechanisms responsible for developmental control of ABA synthesis in plant tissues are poorly understood. Five of the nine CCD genes present in the Arabidopsis genome encode NCED's involved in control of ABA synthesis in the plant. This project is focused on functional analysis of these five AtNCED genes as a key to understanding developmental regulation of ABA synthesis and dissecting the role of ABA in plant development. For this purpose, the project developed a comprehensive set of gene knockouts in the AtNCED genes that facilitate genetic dissection of ABA synthesis. These mutants were used in combination with key molecular tools to address the following specific objectives: (1) the role of ABA synthesis in root development; (2) developmental control of ABA synthesis in seeds; (3) analysis of ATNCED over-expressers; (4) preliminary crystallography of the maize VP14 protein.

  6. Incorporation of oxygen into abscisic acid and phaseic acid for molecular oxygen

    International Nuclear Information System (INIS)

    Creelman, R.A.; Zeevaart, J.A.D.

    1984-01-01

    Abscisic acid accumulates in detached, wilted leaves of Xanthium strumariu. When these leaves are subsequently rehydrated, phaseic acid, a catabolite of abscisic acid, accumulates. Analysis by gas chromatography-mass spectrometry of phaseic acid isolated from stressed and subsequently rehydrated leaves placed in an atmosphere containing 20% 18 O 2 and 80% N 2 indicates that one atom of 18 O is incorporated in the 6'-hydroxymethyl group of phaseic acid. This suggests that the enzyme that converts abscisic acid to phaseic acid is an oxygenase. Analysis by gas chromatography-mass spectrometry of abscisic acid isolated from stressed leaves kept in an atmosphere containing 18 O 2 indicates that one atom of 18 O is presented in the carboxyl group of abscisic acid. Thus, when abscisic acid accumulates in water-streesed leaves, only one of the four oxygens present in the abscisic acid molecule is derived from molecular oxygen. This suggest that either (a) the oxygen present in the 1'-, 4'-, and one of the two oxygens at the 1-position of abscisic acid arise from water, or (b) there exists a stored precursor with oxygen atoms already present in the 1'- and 4'-positions of abscisic acid which is converted to abscisic acid under conditions of water stress. 17 references, 2 figures, 1 tables

  7. Simultaneous treatment with tebuconazole and abscisic acid induces drought and salinity stress tolerance in Arabidopsis thaliana by maintaining key plastid protein levels.

    Science.gov (United States)

    Horn, Ruth; Chudobova, Ivana; Hänsel, Ulrike; Herwartz, Denise; Koskull-Döring, Pascal von; Schillberg, Stefan

    2013-03-01

    Arabidopsis thaliana plants were treated simultaneously with the fungicide tebuconazole and the phytohormone abscisic acid (ABA). We carried out comparative proteomic and transcriptomic analysis against untreated controls under different stress regimes. The chemicals were applied 24 h before the onset of drought stress (removal of the nutrient medium) or salinity stress (hydroponic culture using 150 mM NaCl), and samples were taken during the stress treatments and after a 24 h recovery period. The combined chemical treatment protected plants against both forms of stress. Difference in-gel electrophoresis revealed 18 and 34 unique protein markers representing induced tolerance to drought and salinity stress, respectively. Most of the markers represented plastid functions (such as CO(2) fixation and photosystem II activity), and their abundance was reduced under stress conditions but maintained at near normal levels in the treated plants. The corresponding transcripts were reduced in abundance primarily under drought stress but not salinity stress, indicating that the signal transduction pathways activated by tebuconazole/ABA treatment depend on the nature of the stress stimulus.

  8. Expression analysis of nine small heat shock protein genes from Tamarix hispida in response to different abiotic stresses and abscisic acid treatment.

    Science.gov (United States)

    Yang, Guiyan; Wang, Yucheng; Zhang, Kaimin; Gao, Caiqiu

    2014-03-01

    Heat shock proteins (HSPs) play important roles in protecting plants against environmental stresses. Furthermore, small heat shock proteins (sHSPs) are the most ubiquitous HSP subgroup with molecular weights ranging from 15 to 42 kDa. In this study, nine sHSP genes (designated as ThsHSP1-9) were cloned from Tamarix hispida. Their expression patterns in response to cold, heat shock, NaCl, PEG and abscisic acid (ABA) treatments were investigated in the roots and leaves of T. hispida by real-time RT-PCR analysis. The results showed that most of the nine ThsHSP genes were expressed at higher levels in roots than in leaves under normal growth condition. All of ThsHSP genes were highly induced under conditions of cold (4 °C) and different heat shocks (36, 40, 44, 48 and 52 °C). Under NaCl stress, all nine ThsHSPs genes were up-regulated at least one stress time-point in both roots and leaves. Under PEG and ABA treatments, the nine ThsHSPs showed various expression patterns, indicating a complex regulation pathway among these genes. This study represents an important basis for the elucidation of ThsHSP gene function and provides essential information that can be used for stress tolerance genetic engineering in future studies.

  9. Effect of activated charcoal, abscisic acid and polyethylene glycol on ...

    African Journals Online (AJOL)

    USER

    2010-06-21

    Jun 21, 2010 ... The influence of activated charcoal (AC), abscisic acid (ABA) and polyethylene glycol (PEG) on the maturation and conversion of horse chestnut (Aesculus hippocastanum L.) androgenic embryos were tested. Androgenic embryos originating from microspores and anther culture were maturated over 90.

  10. Abscisic acid and assimilate partitioning during seed development

    NARCIS (Netherlands)

    Bruijn, de S.M.

    1993-01-01

    This thesis describes the influence of abscisic acid (ABA) on the transport of assimilates to seeds and the deposition of reserves in seeds. It is well-known from literature that ABA accumulates in seeds during development, and that ABA concentrations in seeds correlate rather well with

  11. Relationship between abscisic acid (ABA) concentration and some ...

    African Journals Online (AJOL)

    This work investigated the effects of endogenous abscisic acid (ABA) and physiologic parameters related to yield in two wheat cultivars (Triticum aestivum L.), Marvdasht and Zagros (sensitive and tolerant to terminal season drought, respectively) grown in pots under well watered and water-stressed starting from anthesis ...

  12. Abscisic acid represses the transcription of chloroplast genes

    Czech Academy of Sciences Publication Activity Database

    Yamburenko, M.V.; Zubo, Y.O.; Vaňková, Radomíra; Kusnetsov, V.; Kulaeva, O.N.; Borner, T.

    2013-01-01

    Roč. 64, č. 14 (2013), s. 4491-4502 ISSN 0022-0957 R&D Projects: GA ČR GA522/09/2058 Institutional research plan: CEZ:AV0Z50380511 Keywords : Abscisic acid (ABA) * chloroplast * cytokinin Subject RIV: ED - Physiology Impact factor: 5.794, year: 2013

  13. [Tissue culture of medicinal plant and abscisic acid].

    Science.gov (United States)

    Fang, Hui-Yong; Zhu, Hong; Yao, Jian-Xun; Jia, Cai-Feng; Shan, Gao-Wei; Li, Min-Hui

    2013-01-01

    Abscisic acid (ABA) plays a key role in many physiological processes of plants, and it was also applied to fields of medicinal plant biotechnology. The article presents a review of some recent application of ABA in enhancing the production of secondary metabolites of medicinal plants, improving the in vitro conservation in medicinal plant tissue culture system.

  14. Effect of activated charcoal, abscisic acid and polyethylene glycol on ...

    African Journals Online (AJOL)

    Effect of activated charcoal, abscisic acid and polyethylene glycol on maturation, germination and conversion of Aesculus hippocastanum androgenic embryos. ... rapid development of embryos in the cotyledonary stage and lowered percentage of abnormal structures. The best results of androgenic microspore embryo ...

  15. Mitogen-activated protein kinase and abscisic acid signal transduction

    NARCIS (Netherlands)

    Heimovaara-Dijkstra, S.; Testerink, C.; Wang, M.

    1998-01-01

    The phytohormone abscisic acid (ABA) is a classical plant hormone, responsible for regulation of abscission, diverse aspects of plant and seed development, stress responses and germination. It was found that ABA signal transduction in plants can involve the activity of type 2C-phosphatases (PP2C),

  16. Sinapic acid or its derivatives interfere with abscisic acid homeostasis during Arabidopsis thaliana seed germination.

    Science.gov (United States)

    Bi, Baodi; Tang, Jingliang; Han, Shuang; Guo, Jinggong; Miao, Yuchen

    2017-06-06

    Sinapic acid and its esters have broad functions in different stages of seed germination and plant development and are thought to play a role in protecting against ultraviolet irradiation. To better understand the interactions between sinapic acid esters and seed germination processes in response to various stresses, we analyzed the role of the plant hormone abscisic acid (ABA) in the regulation of sinapic acid esters involved in seed germination and early seedling growth. We found that exogenous sinapic acid promotes seed germination in a dose-dependent manner in Arabidopsis thaliana. High-performance liquid chromatography mass spectrometry analysis showed that exogenous sinapic acid increased the sinapoylcholine content of imbibed seeds. Furthermore, sinapic acid affected ABA catabolism, resulting in reduced ABA levels and increased levels of the ABA-glucose ester. Using mutants deficient in the synthesis of sinapate esters, we showed that the germination of mutant sinapoylglucose accumulator 2 (sng2) and bright trichomes 1 (brt1) seeds was more sensitive to ABA than the wild-type. Moreover, Arabidopsis mutants deficient in either abscisic acid deficient 2 (ABA2) or abscisic acid insensitive 3 (ABI3) displayed increased expression of the sinapoylglucose:choline sinapoyltransferase (SCT) and sinapoylcholine esterase (SCE) genes with sinapic acid treatment. This treatment also affected the accumulation of sinapoylcholine and free choline during seed germination. We demonstrated that sinapoylcholine, which constitutes the major phenolic component in seeds among various minor sinapate esters, affected ABA homeostasis during seed germination and early seedling growth in Arabidopsis. Our findings provide insights into the role of sinapic acid and its esters in regulating ABA-mediated inhibition of Arabidopsis seed germination in response to drought stress.

  17. CCCH-type zinc finger family in maize: genome-wide identification, classification and expression profiling under abscisic acid and drought treatments.

    Directory of Open Access Journals (Sweden)

    Xiaojian Peng

    Full Text Available BACKGROUND: CCCH-type zinc finger proteins comprise a large protein family. Increasing evidence suggests that members of this family are RNA-binding proteins with regulatory functions in mRNA processing. Compared with those in animals, functions of CCCH-type zinc finger proteins involved in plant growth and development are poorly understood. METHODOLOGY/PRINCIPAL FINDINGS: Here, we performed a genome-wide survey of CCCH-type zinc finger genes in maize (Zea mays L. by describing the gene structure, phylogenetic relationships and chromosomal location of each family member. Promoter sequences and expression profiles of putative stress-responsive members were also investigated. A total of 68 CCCH genes (ZmC3H1-68 were identified in maize and divided into seven groups by phylogenetic analysis. These 68 genes were found to be unevenly distributed on 10 chromosomes with 15 segmental duplication events, suggesting that segmental duplication played a major role in expansion of the maize CCCH family. The Ka/Ks ratios suggested that the duplicated genes of the CCCH family mainly experienced purifying selection with limited functional divergence after duplication events. Twelve maize CCCH genes grouped with other known stress-responsive genes from Arabidopsis were found to contain putative stress-responsive cis-elements in their promoter regions. Seven of these genes chosen for further quantitative real-time PCR analysis showed differential expression patterns among five representative maize tissues and over time in response to abscisic acid and drought treatments. CONCLUSIONS: The results presented in this study provide basic information on maize CCCH proteins and form the foundation for future functional studies of these proteins, especially for those members of which may play important roles in response to abiotic stresses.

  18. The effect of drought stress and exogenous abscisic acid on growth ...

    African Journals Online (AJOL)

    Jane

    2011-08-17

    Aug 17, 2011 ... Full Length Research Paper. The effect of drought stress and exogenous abscisic acid on growth ... and sedative properties, folk herbal medicines have used it for the treatment of numerous illnesses for centuries ..... Eucalyptus camaldulensis seedlings. Australian J. Plant Physiol. 18: 153-163. Gowing DJ ...

  19. Glutathione reductase in leaves of cowpea: cloning of two cDNAs, expression and enzymatic activity under progressive drought stress, desiccation and abscisic acid treatment.

    Science.gov (United States)

    Contour-Ansel, Dominique; Torres-Franklin, Maria Lucia; Cruz DE Carvalho, Maria Helena; D'Arcy-Lameta, Agnès; Zuily-Fodil, Yasmine

    2006-12-01

    Reactive oxygen species are frequently produced when plants are exposed to abiotic stresses. Among the detoxication systems, two enzymes, ascorbate peroxidase and glutathione reductase (GR) play key roles. GR has also a central role in keeping the reduced glutathione pool during stress thus allowing the adjustments on the cellular redox reactions. The aim of this work was to study the variations in cytosolic and dual-targeted GR gene expression in the leaves of cowpea plants submitted to progressive drought, rapid desiccation and application of exogenous abscisic acid (ABA). Two cowpea (Vigna unguiculata) cultivars, one drought-resistant ('EPACE-1'), the other drought-sensitive ('1183') were submitted to progressive drought stress by withholding irrigation. Cut-off leaves were air-dried or treated with exogenous ABA. Two GR cDNAs, one cytosolic, the other dual-targeted to chloroplasts and mitochondria were isolated by PCR and cloned in plasmid vectors. Reverse-transcription PCR was used to study the variations in GR gene expression. Two new cDNAs encoding a putative dual-targeted and a cytosolic GR were cloned and sequenced from leaves of V. unguiculata. Drought stress induced an up-regulation of the expression of the cytosolic GR gene directly related to the intensity of the stress in both cultivars. The expression of dual-targeted GR was up-regulated by the drought treatment in the susceptible cultivar only. Under a fast desiccation, the '1183' cultivar responded later than the 'EPACE-1', although in 'EPACE-1' it was the cytosolic isoform which responded and in '1183' the dual-targeted one. Exogenous ABA enhanced significantly the activity and expression levels of GR in both cultivars after treatment for 24 h. These results demonstrate a noticeable activation in both cultivars of the antioxidant metabolism under a progressive water stress, which involves both GR genes in the case of the susceptible cultivar. Under a fast desiccation, the susceptible cultivar

  20. Compartmentation and equilibration of abscisic acid in isolated Xanthium cells

    International Nuclear Information System (INIS)

    Bray, E.A.; Zeevaart, J.A.D.

    1986-01-01

    The compartmentation of endogenous abscisic acid (ABA), applied (+/-)-[ 3 H]ABA, and (+/-)-trans-ABA was measured in isolated mesophyll cells of the Chicago strain of Xanthium strumarium L. The release of ABA to the medium in the presence or absence of DMSO was used to determine the equilibration of ABA in the cells. It was found that a greater percentage of the (+/-)-[ 3 H]ABA and the (+/-)-trans-ABA was released into the medium than of the endogenous ABA, indicating that applied ABA did not equilibrate with the endogenous material. Therefore, in further investigations only the compartmentation of endogenous ABA was studied. Endogenous ABA was released from Xanthium cells according to the pH gradients among the various cellular compartments. Thus, darkness, high external pH, KNO 2 , and drought-stress all increased the efflux of ABA from the cells. Efflux of ABA from the cells in the presence of 0.6 M mannitol occurred within 30 seconds, but only 8% of the endogenous material was released during the 20 minute treatment

  1. ABSCISIC ACID EFFECTS ON WATER AND PHOTOSYNTHETIC ...

    African Journals Online (AJOL)

    Bidai Y, Achour A and Belkhodja M

    1 mai 2016 ... diverses notamment hydrique et physiologique chez de nombreuses espèces sous l'action de facteurs hormonaux comme l'acide abscissique (ABA) [7, 8]. En effet, diverses contraintes induisent la synthèse de l'ABA, considéré aujourd'hui comme une hormone de stress [9,. 10,11]. Lors d'un stress ...

  2. ABSCISIC ACID EFFECTS ON WATER AND PHOTOSYNTHETIC ...

    African Journals Online (AJOL)

    Bidai Y, Achour A and Belkhodja M

    1 mai 2016 ... signifie que l'acide abscissique a un effet sur les mouvements sto de ce caractère reste fortement influencée par la variabilité génotypi ..... [17] Paul R., Impens R. Les maladies non parasitaires, In: P. Lepoivre (Ed.), Phytopathologie: Bases moléculaires et biologiques des pathosystèmes et fondements des ...

  3. Action of Abscisic Acid on Auxin Transport and its Relation to Phototropism

    DEFF Research Database (Denmark)

    Naqvi, S. M.; Engvild, Kjeld Christensen

    1974-01-01

    The action of abscisic acid on the kinetics of auxin transport through Zea mays L. (cv. Goudster) coleoptiles has been investigated. Abscisic acid applied simultaneously with indoleacetic acid-2-14C in the donor block reduced the transport intensity without materially affecting the basipetal...

  4. EFFECT OF EXOGENOUS ABSCISIC ACID ON GROWTH AND BIOCHEMICAL CHANGES IN THE HALOPHYTE SUAEDA MARITIMA

    Directory of Open Access Journals (Sweden)

    Anbarasi G.

    2015-04-01

    Full Text Available Different types of phytohormones are being extensively used to alleviate the adverse effect of salinity stress on plant growth. Among those, Abscisic acid (ABA is a plant stress hormone and one of the most important signaling molecules in plants. Drought and salinity activate De-novo abscisic acid synthesis prevent further water loss by evaporation through stomata, mediated by changes in the guard cell turgor pressure. Under osmotic stress abscisic acid induce the accumulation of protein involved in the biosynthesis of osmolites which increasing the stress tolerance of plant. In addition, exogenous application of ABA enhances the tolerance of plants or plant cells to cold, heat, drought, anoxia and heavy metal stresses. This study was carried out to study the exogenous abscisic (ABA acid induced regulatory role on the growth, water content, protein content, chlorophyll content, osmolyte accumulation and protein profiling through SDS PAGE in a halophyte, Suaeda maritima. The osmolyte accumulation of proline and glycine betaine was found to be more in 50 µM ABA concentrations. The protein profiling through SDS PAGE revealed that ̴ 66KDa proteins was not expressed in the control plant and in 10μM ABA treated plants. Interestingly, the ABA treatment induced a new protein of 14.2KDa in 10μM concentration. The ABA treated plants with concentrations 50μM, 100μM and 150μM showed changes in the expression of protein in abundance than the control and 10μM ABA treated plants. The findings in this study indicate that among all the concentrations, 50μM ABA concentration treated plants exhibited higher growth rate.

  5. Action of Abscisic Acid on Auxin Transport and its Relation to Phototropism

    DEFF Research Database (Denmark)

    Naqvi, S. M.; Engvild, Kjeld Christensen

    1974-01-01

    The action of abscisic acid on the kinetics of auxin transport through Zea mays L. (cv. Goudster) coleoptiles has been investigated. Abscisic acid applied simultaneously with indoleacetic acid-2-14C in the donor block reduced the transport intensity without materially affecting the basipetal...... velocity or the uptake. No effect on acropetal transport was observed. The data have been used to discuss the similarities in effects of abscisic acid and visible radiation and a hypothesis is proposed to explain the phenomena of phototropism....

  6. 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.

  7. Effect of abscisic acid on the linoleic acid metabolism in developing maize embryos

    Energy Technology Data Exchange (ETDEWEB)

    Abian, J.; Gelpi, E.; Pages, M. (Centro de Investigacion y Desarrollo, Barcelona (Spain))

    1991-04-01

    Partially purified protein extracts from maize (Zea mays L.) embryos, whether treated or not with abscisic acid (ABA), were incubated with linoleic acid (LA) and 1-({sup 14}C)LA. The resulting LA metabolites were monitored by high performance liquid chromatography with a radioactivity detector and identified by gas chromatography-mass spectrometry. {alpha}- and {gamma}-ketol metabolites arising from 9-lipoxygenase activity were the more abundant compounds detected in the incubates, although the corresponding metabolites produced by 13-lipoxygenase were also present in the samples. In addition, a group of stereoisomers originating form two isomeric trihydroxy acids (9,12,13-trihydroxy-10-octadecenoic and 9,10,13-trihydroxy-11-octadecenoic acids) are described. Important variations in the relative proportions of the LA metabolites were observed depending on the embryo developmental stage and on ABA treatment. Two new ABA-induced compounds have been detected. These compounds are present in embryos at all developmental stages, being more abundant in old (60 days) embryos. Furthermore, ABA induction of these compounds is maximum at very young development stages, decreasing as maturation progresses. A tentative structure for these compounds (10-oxo-9,13-dihydroxy-11-octadecenoic acid and 12-oxo-9,13-dihydroxy-10-octadecenoic acid) is also provided. This study revealed an early stage in maize embryogenesis characterized by a higher relative sensitivity to ABA. The physiological importance of ABA on LA metabolism is discussed.

  8. Possible role for abscisic acid in regulation of photosynthetic and photorespiratory carbon metabolism in barley leaves

    International Nuclear Information System (INIS)

    Popova, L.P.; Tsonev, T.D.; Vaklinova, S.G.

    1987-01-01

    The influence of abscisic acid (ABA) on carbon metabolism, rate of photorespiration, and the activity of the photorespiratory enzymes ribulose bisphosphate oxygenase and glycolate oxidase in 7-day-old barley seedlings (Hordeum vulgare L. var. Alfa) was investigated. Plants treated with ABA had enhanced incorporation of labeled carbon from 14 CO 2 into glycolic acid, glycine, and serine, while 14 C incorporation into 3-phosphoglyceric acid and sugarphosphate esters was depressed. Parallel with this effect, treated plants showed a rise in activity of RuBP oxygenase and glycolic acid oxidase. The rate of photorespiration was increased twofold by ABA treatment at IO -6 molar while the CO 2 -compensation point increased 46% and stomatal resistance increased more than twofold over control plants

  9. Abscisic acid biosynthesis in water-stressed leaves

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yi.

    1989-01-01

    Although abscisic acid (ABA) was discovered 30 years ago, very little is known about its biosynthetic pathway in higher plants. Two hypotheses have been proposed: (i) a direct pathway involving only C-15 intermediates like farnesyl pyrophosphate, (ii) an indirect pathway involving C-40 intermediates like the xanthophylls. When {sup 14}CO{sub 2} was fed into greened bean plants, the {sup 14}C specific activity of ABA was always lower than those in xanthophylls, such as violaxanthin and lutein, regardless of {sup 12}CO{sub 2} chase periods. The ABA accumulation in green leaves was not affected by fluridone when plants were stressed once, but the {sup 14}C incorporation into ABA was inhibited to the same extent as those of xanthophylls. The incorporation of {sup 18}O into the ABA ring when violaxanthin was labeled by {sup 18}O in vivo via the violaxanthin cycle indicates that at least a portion of ABA was derived from {sup 18}O-labeled violaxanthin during water stress.

  10. Plants, endosymbionts and parasites: Abscisic acid and calcium signaling.

    Science.gov (United States)

    Nagamune, Kisaburo; Xiong, Liming; Chini, Eduardo; Sibley, L David

    2008-01-01

    It was recently discovered that the protozoan parasite, Toxoplasma gondii produces and uses the plant hormone, abscisic acid (ABA), for communication. Following intracellular replication, ABA production influences the timing of parasite egress from the host cell. This density-dependent signal may serve to coordinate exit from the host cell in a synchronous manner by triggering calcium-dependent activation of motility. In the absence of ABA production, parasites undergo differentiation to the semidormant, tissue cyst. The pathway for ABA production in T. gondii may be derived from a relict endosymbiont, acquired by ingestion of a red algal cell. Although the parasite has lost the capacity for photosynthesis, the plant-like nature of this signaling pathway may be exploited to develop new drugs. In support of this idea, an inhibitor of ABA biosynthesis protected mice against lethal infection with T. gondii. Here, we compare the role of ABA in parasites to its activities in plants, where it is know to control development and stress responses.

  11. Transcriptome profiling during mangrove viviparity in response to abscisic acid.

    Science.gov (United States)

    Hong, Liwei; Su, Wenyue; Zhang, Yuanye; Ye, Congting; Shen, Yingjia; Li, Qingshun Q

    2018-01-15

    Mangrove plants adapt to coastal tidal mudflats with specially evolved viviparity seed development. However, very little is known about the genetic and molecular mechanisms of mangrove viviparity. Here, we tested a hypothesis that plant hormone abscisic acid (ABA) plays a significant role in precocious germination of viviparous Kandelia obovata seeds by exogenous applications. Through transcriptome analysis of ABA treated seeds, it was found that ABA repressed mangrove fruit growth and development, and there were thousands of genes differentially expressed. As a result, dynamics of the pathways were dramatically altered. In particular, "Plant hormone signal transduction" and "MAPK signaling pathway" were represented significantly. Among differentially expressed genes, some key genes of ABA signal transduction were induced, while ABA biosynthesis genes were repressed. Take ABI1 and ABI2, key negative regulators in ABA signal pathway, as examples, homologous alignment and a phylogenetic tree in various species showed that ABI1 and ABI2 are highly conserved among various species. The functional similarity of these genes was confirmed by transgenic work in Arabidopsis. Taken together, ABA inhibited mangrove viviparity, but mangroves developed a mechanism to prevent accidently increase of ABA in the harsh environment for maintaining viviparous reproductive strategy.

  12. Abscisic acid enhances cold tolerance in honeybee larvae.

    Science.gov (United States)

    Ramirez, Leonor; Negri, Pedro; Sturla, Laura; Guida, Lucrezia; Vigliarolo, Tiziana; Maggi, Matías; Eguaras, Martín; Zocchi, Elena; Lamattina, Lorenzo

    2017-04-12

    The natural composition of nutrients present in food is a key factor determining the immune function and stress responses in the honeybee ( Apis mellifera ). We previously demonstrated that a supplement of abscisic acid (ABA), a natural component of nectar, pollen, and honey, increases honeybee colony survival overwinter. Here we further explored the role of ABA in in vitro -reared larvae exposed to low temperatures. Four-day-old larvae (L4) exposed to 25°C for 3 days showed lower survival rates and delayed development compared to individuals growing at a standard temperature (34°C). Cold-stressed larvae maintained higher levels of ABA for longer than do larvae reared at 34°C, suggesting a biological significance for ABA. Larvae fed with an ABA-supplemented diet completely prevent the low survival rate due to cold stress and accelerate adult emergence. ABA modulates the expression of genes involved in metabolic adjustments and stress responses: Hexamerin 70b, Insulin Receptor Substrate, Vitellogenin , and Heat Shock Proteins 70. AmLANCL2, the honeybee ABA receptor, is also regulated by cold stress and ABA. These results support a role for ABA increasing the tolerance of honeybee larvae to low temperatures through priming effects. © 2017 The Author(s).

  13. Abscisic acid controlled sex before transpiration in vascular plants.

    Science.gov (United States)

    McAdam, Scott A M; Brodribb, Timothy J; Banks, Jo Ann; Hedrich, Rainer; Atallah, Nadia M; Cai, Chao; Geringer, Michael A; Lind, Christof; Nichols, David S; Stachowski, Kye; Geiger, Dietmar; Sussmilch, Frances C

    2016-10-26

    Sexual reproduction in animals and plants shares common elements, including sperm and egg production, but unlike animals, little is known about the regulatory pathways that determine the sex of plants. Here we use mutants and gene silencing in a fern species to identify a core regulatory mechanism in plant sexual differentiation. A key player in fern sex differentiation is the phytohormone abscisic acid (ABA), which regulates the sex ratio of male to hermaphrodite tissues during the reproductive cycle. Our analysis shows that in the fern Ceratopteris richardii, a gene homologous to core ABA transduction genes in flowering plants [SNF1-related kinase2s (SnRK2s)] is primarily responsible for the hormonal control of sex determination. Furthermore, we provide evidence that this ABA-SnRK2 signaling pathway has transitioned from determining the sex of ferns to controlling seed dormancy in the earliest seed plants before being co-opted to control transpiration and CO 2 exchange in derived seed plants. By tracing the evolutionary history of this ABA signaling pathway from plant reproduction through to its role in the global regulation of plant-atmosphere gas exchange during the last 450 million years, we highlight the extraordinary effect of the ABA-SnRK2 signaling pathway in plant evolution and vegetation function.

  14. Plant water stress: Associations between ethylene and abscisic acid response

    Directory of Open Access Journals (Sweden)

    Carolina Salazar

    2015-08-01

    Full Text Available Agriculture is severely impacted by water stress due either to excess (hypoxia/anoxia or deficit of water availability. Hypoxia/anoxia is associated with oxygen (O2 deficiency or depletion, inducing several anatomical, morphological, physiological, and molecular changes. The majority of these alterations are adaptive mechanisms to cope with low O2 availability; among them, alterations in shoot length, aerenchyma formation and adventitious roots have been described in several studies. The aim of this review was to address the association between abscisic acid (ABA and ethylene in function of water availability in plants. The major physiological responses to low O2 are associated with changes in root respiration, stomatal conductance, photosynthesis, and fermentation pathways in roots. In addition, several changes in gene expression have been associated with pathways that are not present under normal O2 supply. The expression of ethylene receptor genes is up-regulated by low O2, and ethylene seems to have a crucial role in anatomical and physiological effects during hypoxia/anoxia. During O2 depletion, ethylene accumulation down-regulates ABA by inhibiting rate-limiting enzymes in ABA biosynthesis and by activating ABA breakdown to phaseic acid. With regard to water deficit, drought is primarily sensed by the roots, inducing a signal cascade to the shoots via xylem causing physiological and morphological changes. Several genes are regulated up or down with osmotic stress; the majority of these responsive genes can be driven by either an ABA-dependent or ABA-independent pathway. Some studies suggest that ethylene shuts down leaf growth very fast after the plant senses limited water availability. Ethylene accumulation can antagonize the control of gas exchange and leaf growth upon drought and ABA accumulation.

  15. Involvement of abscisic acid in correlative control of flower abscission in soybean

    International Nuclear Information System (INIS)

    Yarrow, G.L.

    1985-01-01

    Studies were carried out in three parts: (1) analysis of endogenous abscisic acid (ABA) in abscising and non-abscising flowers, (2) partitioning of radio-labelled ABA and photoassimilates within the soybean raceme, and (3) shading experiments, wherein endogenous levels, metabolism and partitioning of ABA were determined. Endogenous concentrations of ABA failed to show any consistent relationship to abscission of soybean flowers. Partitioning of radiolabelled ABA and photoassimilates displayed consistently higher sink strengths (% DPM) for both 3 H-ABA and 14 C-photoassimilates for non-abscising flowers than for abscising flowers within control racemes. Shading flowers with aluminum foil, 48 hrs prior to sampling, resulted in lowered endogenous ABA concentrations at 12, 17 and 22 days after anthesis (DAA), but not at 0 or 4 DAA. No differences were found in the catabolism of 3 H-ABA between shaded (abscising) and non-shaded (non-abscising) flowers. Reduced partitioning of ABA and photoassimilates to shaded flowers resulted when shades were applied at 0, 4, 12, and 17 DAA, but not at 22 DAA

  16. Overexpression of Poplar Pyrabactin Resistance-Like Abscisic Acid Receptors Promotes Abscisic Acid Sensitivity and Drought Resistance in Transgenic Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Jingling Yu

    Full Text Available Drought stress is an important environmental factor limiting productivity of plants, especially fast growing species with high water consumption like poplar. Abscisic acid (ABA is a phytohormone that positively regulates seed dormancy and drought resistance. The PYR1 (Pyrabactin Resistance 1/ PYRL (PYR-Like/ RCAR (Regulatory Component of ABA Receptor (PYR/PYL/RCAR ABA receptor family has been identified and widely characterized in Arabidopsis thaliana. However, their functions in poplars remain unknown. Here, we report that 2 of 14 PYR/PYL/RCAR orthologues in poplar (Populus trichocarpa (PtPYRLs function as a positive regulator of the ABA signal transduction pathway. The Arabidopsis transient expression and yeast two-hybrid assays showed the interaction among PtPYRL1 and PtPYRL5, a clade A protein phosphatase 2C, and a SnRK2, suggesting that a core signalling complex for ABA signaling pathway exists in poplars. Phenotypic analysis of PtPYRL1 and PtPYRL5 transgenic Arabidopsis showed that these two genes positively regulated the ABA responses during the seed germination. More importantly, the overexpression of PtPYRL1 and PtPYRL5 substantially improved ABA sensitivity and drought stress tolerance in transgenic plants. In summary, we comprehensively uncovered the properties of PtPYRL1 and PtPYRL5, which might be good target genes to genetically engineer drought-Resistant plants.

  17. Effect of abscisic acid on amino acid uptake and efflux in developing soybean seeds

    International Nuclear Information System (INIS)

    Guldan, S.J.; Brun, W.A.

    1987-01-01

    The role of abscisic acid (ABA) in regulating growth of developing soybean [Glycine max (L.) Merr.] seeds is not fully understood. The objectives of this study were to characterize the effect of ABA on the in vitro uptake of asparagine and glutamine by isolated immature cotyledons in three soybean plant introduction (PI) lines with genotypic differences in seed growth rate and final seed weight. Cotyledons were incubated in uptake buffer solutions plus 14 C-asparagine or 14 C-glutamine and treatment concentrations of ABA. The ABA levels in the uptake solutions were 0, 10 -7 , 10 -6 , and 10 -5 M. The uptake rate of glutamine was approximately three times that of asparagine. Among PI lines, the heavy seeded line had a greater rate of asparagine uptake while the light seeded line had a greater rate of glutamine uptake. For asparagine, 10 -6 M ABA depressed uptake compared to the control. For glutamine, ABA enhanced uptake compared to the control at both 10 -6 and 10 -5 M. In an additional experiment, the authors observed no effect of ABA and K on the release of labeled asparagine from excised soybean seed coats. These data indicate that amino acid uptake rates are genotypically dependent and may be influenced by ABA concentration

  18. In vitro reconstitution of an abscisic acid signalling pathway

    KAUST Repository

    Fujii, Hiroaki

    2009-11-18

    The phytohormone abscisic acid (ABA) regulates the expression of many genes in plants; it has critical functions in stress resistance and in growth and development. Several proteins have been reported to function as ABA receptors, and many more are known to be involved in ABA signalling. However, the identities of ABA receptors remain controversial and the mechanism of signalling from perception to downstream gene expression is unclear. Here we show that by combining the recently identified ABA receptor PYR1 with the type 2C protein phosphatase (PP2C) ABI1, the serine/threonine protein kinase SnRK2.6/OST1 and the transcription factor ABF2/AREB1, we can reconstitute ABA-triggered phosphorylation of the transcription factor in vitro. Introduction of these four components into plant protoplasts results in ABA-responsive gene expression. Protoplast and test-tube reconstitution assays were used to test the function of various members of the receptor, protein phosphatase and kinase families. Our results suggest that the default state of the SnRK2 kinases is an autophosphorylated, active state and that the SnRK2 kinases are kept inactive by the PP2Cs through physical interaction and dephosphorylation. We found that in the presence of ABA, the PYR/PYL (pyrabactin resistance 1/PYR1-like) receptor proteins can disrupt the interaction between the SnRK2s and PP2Cs, thus preventing the PP2C-mediated dephosphorylation of the SnRK2s and resulting in the activation of the SnRK2 kinases. Our results reveal new insights into ABA signalling mechanisms and define a minimal set of core components of a complete major ABA signalling pathway. © 2009 Macmillan Publishers Limited. All rights reserved.

  19. Abscisic acid ameliorates the systemic sclerosis fibroblast phenotype in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Bruzzone, Santina, E-mail: santina.bruzzone@unige.it [Department of Experimental Medicine, Section of Biochemistry, University of Genova, Viale Benedetto XV 1, 16132 Genova (Italy); Centre of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV 9, 16132 Genova (Italy); Advanced Biotechnology Center, Largo Rosanna Benzi 10, 16132 Genova (Italy); Battaglia, Florinda [Centre of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV 9, 16132 Genova (Italy); Mannino, Elena [Department of Experimental Medicine, Section of Biochemistry, University of Genova, Viale Benedetto XV 1, 16132 Genova (Italy); Parodi, Alessia [Centre of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV 9, 16132 Genova (Italy); Fruscione, Floriana [Department of Experimental Medicine, Section of Biochemistry, University of Genova, Viale Benedetto XV 1, 16132 Genova (Italy); Advanced Biotechnology Center, Largo Rosanna Benzi 10, 16132 Genova (Italy); Basile, Giovanna [Department of Experimental Medicine, Section of Biochemistry, University of Genova, Viale Benedetto XV 1, 16132 Genova (Italy); Salis, Annalisa; Sturla, Laura [Department of Experimental Medicine, Section of Biochemistry, University of Genova, Viale Benedetto XV 1, 16132 Genova (Italy); Centre of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV 9, 16132 Genova (Italy); Negrini, Simone; Kalli, Francesca; Stringara, Silvia [Centre of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV 9, 16132 Genova (Italy); Filaci, Gilberto [Centre of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV 9, 16132 Genova (Italy); Department of Internal Medicine, Viale Benedetto XV 6, 16132 Genova (Italy); and others

    2012-05-25

    Highlights: Black-Right-Pointing-Pointer ABA is an endogenous hormone in humans, regulating different cell responses. Black-Right-Pointing-Pointer ABA reverts some of the functions altered in SSc fibroblasts to a normal phenotype. Black-Right-Pointing-Pointer UV-B irradiation increases ABA content in SSc cultures. Black-Right-Pointing-Pointer SSc fibroblasts could benefit from exposure to ABA and/or to UV-B. -- Abstract: The phytohormone abscisic acid (ABA) has been recently identified as an endogenous hormone in humans, regulating different cell functions, including inflammatory processes, insulin release and glucose uptake. Systemic sclerosis (SSc) is a chronic inflammatory disease resulting in fibrosis of skin and internal organs. In this study, we investigated the effect of exogenous ABA on fibroblasts obtained from healthy subjects and from SSc patients. Migration of control fibroblasts induced by ABA was comparable to that induced by transforming growth factor-{beta} (TGF-{beta}). Conversely, migration toward ABA, but not toward TGF-{beta}, was impaired in SSc fibroblasts. In addition, ABA increased cell proliferation in fibroblasts from SSc patients, but not from healthy subjects. Most importantly, presence of ABA significantly decreased collagen deposition by SSc fibroblasts, at the same time increasing matrix metalloproteinase-1 activity and decreasing the expression level of tissue inhibitor of metalloproteinase (TIMP-1). Thus, exogenously added ABA appeared to revert some of the functions altered in SSc fibroblasts to a normal phenotype. Interestingly, ABA levels in plasma from SSc patients were found to be significantly lower than in healthy subjects. UV-B irradiation induced an almost 3-fold increase in ABA content in SSc cultures. Altogether, these results suggest that the fibrotic skin lesions in SSc patients could benefit from exposure to high(er) ABA levels.

  20. Abscisic acid effects on water and photosynthetic characteristics of ...

    African Journals Online (AJOL)

    The aim of this study is to compare the water and photosynthetic characteristics of two xerophilic ecotypes of Atriplex halimus (L.). Seeds collected from two different sites Djelfa and Oran are germinated in controlled greenhouse. After 6 months, the plantlets were treated 21 days with increasing concentrations of abscisic ...

  1. Large-scale proteome analysis of abscisic acid and ABSCISIC ACID INSENSITIVE3-dependent proteins related to desiccation tolerance in Physcomitrella patens

    International Nuclear Information System (INIS)

    Yotsui, Izumi; Serada, Satoshi; Naka, Tetsuji; Saruhashi, Masashi; Taji, Teruaki; Hayashi, Takahisa; Quatrano, Ralph S.; Sakata, Yoichi

    2016-01-01

    Desiccation tolerance is an ancestral feature of land plants and is still retained in non-vascular plants such as bryophytes and some vascular plants. However, except for seeds and spores, this trait is absent in vegetative tissues of vascular plants. Although many studies have focused on understanding the molecular basis underlying desiccation tolerance using transcriptome and proteome approaches, the critical molecular differences between desiccation tolerant plants and non-desiccation plants are still not clear. The moss Physcomitrella patens cannot survive rapid desiccation under laboratory conditions, but if cells of the protonemata are treated by the phytohormone abscisic acid (ABA) prior to desiccation, it can survive 24 h exposure to desiccation and regrow after rehydration. The desiccation tolerance induced by ABA (AiDT) is specific to this hormone, but also depends on a plant transcription factor ABSCISIC ACID INSENSITIVE3 (ABI3). Here we report the comparative proteomic analysis of AiDT between wild type and ABI3 deleted mutant (Δabi3) of P. patens using iTRAQ (Isobaric Tags for Relative and Absolute Quantification). From a total of 1980 unique proteins that we identified, only 16 proteins are significantly altered in Δabi3 compared to wild type after desiccation following ABA treatment. Among this group, three of the four proteins that were severely affected in Δabi3 tissue were Arabidopsis orthologous genes, which were expressed in maturing seeds under the regulation of ABI3. These included a Group 1 late embryogenesis abundant (LEA) protein, a short-chain dehydrogenase, and a desiccation-related protein. Our results suggest that at least three of these proteins expressed in desiccation tolerant cells of both Arabidopsis and the moss are very likely to play important roles in acquisition of desiccation tolerance in land plants. Furthermore, our results suggest that the regulatory machinery of ABA- and ABI3-mediated gene expression for desiccation

  2. Large-scale proteome analysis of abscisic acid and ABSCISIC ACID INSENSITIVE3-dependent proteins related to desiccation tolerance in Physcomitrella patens

    Energy Technology Data Exchange (ETDEWEB)

    Yotsui, Izumi, E-mail: izumi.yotsui@riken.jp [Department of BioScience, Tokyo University of Agriculture 1-1-1 Sakuragaoka, Setagayaku, Tokyo, 156-8502 (Japan); Serada, Satoshi, E-mail: serada@nibiohn.go.jp [Laboratory of Immune Signal, National Institute of Biomedical Innovation, Health and Nutrition, 7-6-8 Saito-Asagi, Ibaraki, Osaka, 567-0085 (Japan); Naka, Tetsuji, E-mail: tnaka@nibiohn.go.jp [Laboratory of Immune Signal, National Institute of Biomedical Innovation, Health and Nutrition, 7-6-8 Saito-Asagi, Ibaraki, Osaka, 567-0085 (Japan); Saruhashi, Masashi, E-mail: s13db001@mail.saitama-u.ac.jp [Department of BioScience, Tokyo University of Agriculture 1-1-1 Sakuragaoka, Setagayaku, Tokyo, 156-8502 (Japan); Taji, Teruaki, E-mail: t3teruak@nodai.ac.jp [Department of BioScience, Tokyo University of Agriculture 1-1-1 Sakuragaoka, Setagayaku, Tokyo, 156-8502 (Japan); Hayashi, Takahisa, E-mail: t4hayash@nodai.ac.jp [Department of BioScience, Tokyo University of Agriculture 1-1-1 Sakuragaoka, Setagayaku, Tokyo, 156-8502 (Japan); Quatrano, Ralph S., E-mail: rsq@wustl.edu [Department of Biology, Washington University in St. Louis, St. Louis, MO, 63130-4899 (United States); Sakata, Yoichi, E-mail: sakata@nodai.ac.jp [Department of BioScience, Tokyo University of Agriculture 1-1-1 Sakuragaoka, Setagayaku, Tokyo, 156-8502 (Japan)

    2016-03-18

    Desiccation tolerance is an ancestral feature of land plants and is still retained in non-vascular plants such as bryophytes and some vascular plants. However, except for seeds and spores, this trait is absent in vegetative tissues of vascular plants. Although many studies have focused on understanding the molecular basis underlying desiccation tolerance using transcriptome and proteome approaches, the critical molecular differences between desiccation tolerant plants and non-desiccation plants are still not clear. The moss Physcomitrella patens cannot survive rapid desiccation under laboratory conditions, but if cells of the protonemata are treated by the phytohormone abscisic acid (ABA) prior to desiccation, it can survive 24 h exposure to desiccation and regrow after rehydration. The desiccation tolerance induced by ABA (AiDT) is specific to this hormone, but also depends on a plant transcription factor ABSCISIC ACID INSENSITIVE3 (ABI3). Here we report the comparative proteomic analysis of AiDT between wild type and ABI3 deleted mutant (Δabi3) of P. patens using iTRAQ (Isobaric Tags for Relative and Absolute Quantification). From a total of 1980 unique proteins that we identified, only 16 proteins are significantly altered in Δabi3 compared to wild type after desiccation following ABA treatment. Among this group, three of the four proteins that were severely affected in Δabi3 tissue were Arabidopsis orthologous genes, which were expressed in maturing seeds under the regulation of ABI3. These included a Group 1 late embryogenesis abundant (LEA) protein, a short-chain dehydrogenase, and a desiccation-related protein. Our results suggest that at least three of these proteins expressed in desiccation tolerant cells of both Arabidopsis and the moss are very likely to play important roles in acquisition of desiccation tolerance in land plants. Furthermore, our results suggest that the regulatory machinery of ABA- and ABI3-mediated gene expression for desiccation

  3. Possible role of volatile Fatty acids and abscisic Acid in the dormancy of oats.

    Science.gov (United States)

    Berrie, A M

    1979-04-01

    Species of Avena differ markedly in their levels of pre- and post-harvest dormancy. These species offer the opportunity of determining if dormancy is related to the endogenous level of growth inhibitor. Germinability in two species of differing levels of dormancy, common oat Avena sativa L., and wild oat Avena fatua L. was assessed as were the contents of abscisic acid and volatile fatty acids of chain length C(6)-C(10). In A. sativa which did not possess postharvest dormancy there was no correlation between germination and inhibitor levels but in A. fatua the relationship between the content of fatty acid and dormancy was good. The loss of these fatty acids in dry storage by evaporation could explain after ripening.

  4. Endogenous cytokinins, auxins, and abscisic acid in red algae from Brazil

    Czech Academy of Sciences Publication Activity Database

    Yokoya, N. S.; Stirk, W. A.; van Staden, J.; Novák, Ondřej; Turečková, Veronika; Pěnčík, Aleš; Strnad, Miroslav

    2010-01-01

    Roč. 46, č. 6 (2010), s. 1198-1205 ISSN 0022-3646 R&D Projects: GA ČR GA301/08/1649 Institutional research plan: CEZ:AV0Z50380511 Keywords : ENDOGENOUS * CYTOKININS * AUXINS * ABSCISIC ACID * RED * ALGAE * BRAZIL Subject RIV: EF - Botanics Impact factor: 2.239, year: 2010

  5. Exogenous abscisic acid significantly affects proteome in tea plant (Camellia sinensis) exposed to drought stress

    Science.gov (United States)

    Tea [Camellia sinensis (L.) O. Kuntze] is an important economic crop, and drought is the most important abiotic stress affecting yield and quality. Abscisic acid (ABA) is an important phytohormone responsible for activating drought resistance. Increased understanding of ABA effects on tea plant unde...

  6. Abscisic acid and 14-3-3 proteins control K+ channel activity in barley embryonic root

    NARCIS (Netherlands)

    van den Wijngaard, P.W.J.; Sinnige, M.P.; Roobeek, I.; Reumer, C.G.; Mol, J.N.M.; Wang, M.; de Boer, A.H.; Schoonheim, P.J.

    2005-01-01

    Germination of seeds proceeds in general in two phases, an initial imbibition phase and a subsequent growth phase. In grasses like barley, the latter phase is evident as the emergence of the embryonic root (radicle). The hormone abscisic acid (ABA) inhibits germination because it prevents the embryo

  7. Casein kinase 1-Like 3 is required for abscisic acid regulation of ...

    African Journals Online (AJOL)

    Casein kinase 1-Like 3 is required for abscisic acid regulation of seed germination, root growth, and gene expression in Arabidopsis. M Wang, D Yu, X Guo, X Li, J Zhang, L Zhao, H Chang, S Hu, C Zhang, J Shi, X Liu ...

  8. Overexpression of OsWRKY72 gene interferes in the abscisic acid ...

    Indian Academy of Sciences (India)

    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 ...

  9. Interactions between abscisic acid and cytokinins during water stress and subsequent rehydration

    Czech Academy of Sciences Publication Activity Database

    Pospíšilová, Jana; Vágner, Martin; Malbeck, Jiří; Trávníčková, Alena; Baťková, Petra

    2005-01-01

    Roč. 49, - (2005), s. 533-540 ISSN 0006-3134 R&D Projects: GA ČR GA522/02/1099; GA AV ČR(CZ) IAA638105 Institutional research plan: CEZ:AV0Z50380511 Keywords : abscisic acid * cytokinins * water stress Subject RIV: EF - Botanics Impact factor: 0.792, year: 2005

  10. To Stimulate or Inhibit? That Is the Question for the Function of Abscisic Acid

    Czech Academy of Sciences Publication Activity Database

    Humplík, Jan; Bergougnoux, V.; Van Volkenburgh, E.

    2017-01-01

    Roč. 22, č. 10 (2017), s. 830-841 ISSN 1360-1385 R&D Projects: GA MŠk(CZ) LO1204 Grant - others:PPPLZ(CZ) L200381651 Institutional support: RVO:61389030 Keywords : abscisic acid * etiolation * hypocotyl * photomorphogenesis * skotomorphogenesis Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Plant sciences, botany Impact factor: 11.911, year: 2016

  11. Diurnal variation of cytokinin, auxin and abscisic acid levels in tobacco leaves

    Czech Academy of Sciences Publication Activity Database

    Nováková, Marie; Motyka, Václav; Dobrev, Petre; Malbeck, Jiří; Gaudinová, Alena

    2005-01-01

    Roč. 56, č. 421 (2005), s. 2877-2883 ISSN 0022-0957 R&D Projects: GA ČR GA206/03/0369; GA MŠk LN00A081 Institutional research plan: CEZ:AV0Z50380511 Keywords : abscisic acid * auxin * cytokinin Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.336, year: 2005

  12. Biotechnological characteristics of callusogenesis in maize immature embryo culture under the influence of abscisic acid and 6-benzylaminopurine

    Directory of Open Access Journals (Sweden)

    O. E. Abraimova

    2010-02-01

    Full Text Available The effect of abscisic acid and 6-benzylaminopurine on the induction of callus tissue in maize immature embryo culture was studied. For the majority of investigated genotypes abscisic acid stimulated, but 6-benzylaminopurine inhibited the formation of morphogenic calli in induction medium. It was noted that genotype appeared to be an important factor that determined the character of the influence of phytohormonal composition of the medium on the induction of the specific types of calli. Using of 0.04-0.10 mg/l abscisic acid is recommended for biotechnological production of morphogenic callus tissue in dependence of donor plant genotype.

  13. Abscisic Acid and Cytokinin-Induced Osmotic and Antioxidant Regulation in Two Drought-Tolerant and Drought-Sensitive Cultivars of Wheat During Grain Filling Under Water Deficit in Field Conditions

    Directory of Open Access Journals (Sweden)

    Mohammad-Reza SARAFRAZ-ARDAKANI

    2014-09-01

    Full Text Available Phytohormones play critical roles in regulating plant responses to stress. The present study investigates the effect of cytokinin, abscisic acid and cytokinin/abscisic acid interaction on some osmoprotectants and antioxidant parameters induced by drought stress in two wheat cultivars (Triticum aestivum L. of ‘Pishgam’ and ‘MV-17’ as tolerant and sensitive to drought during post-anthesis phase, respectively grown in field conditions. The most considerable effect of the treatments was exhibited 21 days after anthesis. Under drought conditions, the flag leaf soluble carbohydrate content increased in both cultivars while starch content was remarkably decreased in ‘Pishgam’ as compared to ‘MV-17’. Abscisic acid increased total soluble sugar and reduced starch more than other hormonal treatments, although it decreased studied monosaccharaides in ‘Pishgam’, especially. Drought stress induced high proportion of gylycinebetain and free proline in ‘Pishgam’ cultivar. Application of abscisic acid and cytokinin/abscisic acid interaction increased gylycinebetain and proline content in both cultivars under irrigation and drought conditions. The tolerant cultivar exhibited less accumulation of hydrogen peroxide and malondialdehyde in relation to significant increase of catalase and peroxidase activities and α-tocpherol content under drought conditions. All hormonal treatments increased the named enzyme activities under both irrigation and drought conditions, while higher accumulation of α-tocopherol was only showed in case of cytokinin application. Also, abscisic acid and cytokinin/abscisic acid could decrease drought-induced hydrogen peroxide and malondialdehyde level to some extent, although abscisic acid increased both of hydrogen peroxide andmalondialdehyde content in irrigation phase, especially.

  14. Three Genes That Affect Sugar Sensing (Abscisic Acid Insensitive 4, Abscisic Acid Insensitive 5, and Constitutive Triple Response 1) Are Differentially Regulated by Glucose in Arabidopsis1

    Science.gov (United States)

    Arroyo, Analilia; Bossi, Flavia; Finkelstein, Ruth R.; León, Patricia

    2003-01-01

    Mutant characterization has demonstrated that ABI4 (Abscisic Acid [ABA] Insensitive 4), ABI5 (ABA Insensitive 5), and CTR1 (Constitutive Triple Response 1) genes play an important role in the sugar signaling response in plants. The present study shows that the transcripts of these three genes are modulated by glucose (Glc) independently of the developmental arrest caused by high Glc concentrations. ABI4 and ABI5 transcripts accumulate in response to sugars, whereas the CTR1 transcript is transiently reduced followed by a rapid recovery. The results of our kinetic studies on gene expression indicate that ABI4, ABI5, and CTR1 are regulated by multiple signals including Glc, osmotic stress, and ABA. However, the differential expression profiles caused by these treatments suggest that distinct signaling pathways are used for each signal. ABI4 and ABI5 response to the Glc analog 2-deoxy-Glc supports this conclusion. Glc regulation of ABI4 and CTR1 transcripts is dependent on the developmental stage. Finally, the Glc-mediated regulation of ABI4 and ABI5 is affected in mutants displaying Glc-insensitive phenotypes such as gins, abas, abi4, abi5, and ctr1 but not in abi1-1, abi2-1, and abi3-1, which do not show a Glc-insensitive phenotype. The capacity of transcription factors, like the ones analyzed in this work, to be regulated by a variety of signals might contribute to the ability of plants to respond in a flexible and integral way to continuous changes in the internal and external environment. PMID:12970489

  15. Color of berry and juice of 'Isabel' grape treated with abscisic acid in different ripening stages

    Directory of Open Access Journals (Sweden)

    Lilian Yukari Yamamoto

    2015-12-01

    Full Text Available Abstract : The objective of this work was to evaluate the effect of (S-cis-abscisic acid (S-ABA application at different ripening stages, in increasing phenolic compounds and color of berry and juice of 'Isabel' grape (Vitis labrusca. The evaluated treatments were: control, without S-ABA application; 400 mg L-1S-ABA applied 7 days before veraison (DBV + 400 mg L-1S-ABA at 35 days after first application (DAFA; 400 mg L-1S-ABA applied at veraison (V + 400 mg L-1S-ABA at 35 DAFA; and 400 mg L-1S-ABA applied 7 days after veraison (DAV + 400 mg L-1S-ABA at 35 DAFA. There was no difference among treatments regarding the physical characteristics of berries and clusters, as well as total polyphenols in berry and juice. However, there was an increase in total anthocyanins in berry and juice with S-ABA application. Colorimetric variables indicated the increase in color of berry treated with S-ABA. Juices produced from grapes treated with S-ABA were more appreciated by tasters. The treatments with 400 mg L-1S-ABA applied 7 days before, during, or 7 days after veraison, combined with an additional application 35 days after the first one, increment total anthocyanin concentration and color of berry and juice of 'Isabel' grape, with better juice acceptance, without affecting total polyphenol concentration.

  16. Effect of Exogenous Abscisic Acid and Methyl Jasmonate on Anthocyanin Composition, Fatty Acids, and Volatile Compounds of Cabernet Sauvignon (Vitis vinifera L.) Grape Berries.

    Science.gov (United States)

    Ju, Yan-Lun; Liu, Min; Zhao, Hui; Meng, Jiang-Fei; Fang, Yu-Lin

    2016-10-12

    The anthocyanin composition, fatty acids, and volatile aromas are important for Cabernet Sauvignon grape quality. This study evaluated the effect of exogenous abscisic acid (ABA) and methyl jasmonate (MeJA) on the anthocyanin composition, fatty acids, lipoxygenase activity, and the volatile compounds of Cabernet Sauvignon grape berries. Exogenous ABA and MeJA improved the content of total anthocyanins (TAC) and individual anthocyanins. Lipoxygenase (LOX) activity also increased after treatment. Furthermore, 16 fatty acids were detected. The linoleic acid concentration gradually increased with ABA concentration. The fatty acid content decreased with increasing MeJA concentration and then increased again, with the exception of linoleic acid. After exogenous ABA and MeJA treatment, the C6 aroma content increased significantly. Interestingly, the exogenous ABA and MeJA treatments improved mainly the content of 1-hexanol, hexanal, and 2-heptanol. These results provide insight into the effect of plant hormones on wine grapes, which is useful for grape quality improvement.

  17. Response of cytokinin pool and cytokinin oxidase/dehydrogenase activity to abscisic acid exhibits organ specificity in peas

    Czech Academy of Sciences Publication Activity Database

    Vaseva, I.; Todorova, D.; Malbeck, Jiří; Trávníčková, Alena; Macháčková, Ivana

    2008-01-01

    Roč. 30, č. 2 (2008), s. 151-155 ISSN 0137-5881 Institutional research plan: CEZ:AV0Z50380511 Keywords : Abscisic acid * Cytokinins * Cytokinin Subject RIV: EF - Botanics Impact factor: 0.807, year: 2008

  18. Abscisic acid deficiency increases defence responses against Myzus persicae in Arabidopsis.

    Science.gov (United States)

    Hillwig, Melissa S; Chiozza, Mariana; Casteel, Clare L; Lau, Siau Ting; Hohenstein, Jessica; Hernández, Enrique; Jander, Georg; MacIntosh, Gustavo C

    2016-02-01

    Comparison of Arabidopsis thaliana (Arabidopsis) gene expression induced by Myzus persicae (green peach aphid) feeding, aphid saliva infiltration and abscisic acid (ABA) treatment showed a significant positive correlation. In particular, ABA-regulated genes are over-represented among genes that are induced by M. persicae saliva infiltration into Arabidopsis leaves. This suggests that the induction of ABA-related gene expression could be an important component of the Arabidopsis-aphid interaction. Consistent with this hypothesis, M. persicae populations induced ABA production in wild-type plants. Furthermore, aphid populations were smaller on Arabidopsis aba1-1 mutants, which cannot synthesize ABA, and showed a significant preference for wild-type plants compared with the mutant. Total free amino acids, which play an important role in aphid nutrition, were not altered in the aba1-1 mutant line, but the levels of isoleucine (Ile) and tryptophan (Trp) were differentially affected by aphids in wild-type and mutant plants. Recently, indole glucosinolates have been shown to promote aphid resistance in Arabidopsis. In this study, 4-methoxyindol-3-ylmethylglucosinolate was more abundant in the aba1-1 mutant than in wild-type Arabidopsis, suggesting that the induction of ABA signals that decrease the accumulation of defence compounds may be beneficial for aphids. © 2015 BSPP AND JOHN WILEY & SONS LTD.

  19. Abscisic Acid Determines Basal Susceptibility of Tomato to Botrytis cinerea and Suppresses Salicylic Acid-Dependent Signaling Mechanisms1

    Science.gov (United States)

    Audenaert, Kris; De Meyer, Geert B.; Höfte, Monica M.

    2002-01-01

    Abscisic acid (ABA) is one of the plant hormones involved in the interaction between plants and pathogens. In this work, we show that tomato (Lycopersicon esculentum Mill. cv Moneymaker) mutants with reduced ABA levels (sitiens plants) are much more resistant to the necrotrophic fungus Botrytis cinerea than wild-type (WT) plants. Exogenous application of ABA restored susceptibility to B. cinerea in sitiens plants and increased susceptibility in WT plants. These results indicate that ABA plays a major role in the susceptibility of tomato to B. cinerea. ABA appeared to interact with a functional plant defense response against B. cinerea. Experiments with transgenic NahG tomato plants and benzo(1,2,3)thiadiazole-7-carbothioic acid demonstrated the importance of salicylic acid in the tomato-B. cinerea interaction. In addition, upon infection with B. cinerea, sitiens plants showed a clear increase in phenylalanine ammonia lyase activity, which was not observed in infected WT plants, indicating that the ABA levels in healthy WT tomato plants partly repress phenylalanine ammonia lyase activity. In addition, sitiens plants became more sensitive to benzo(1,2,3)thiadiazole-7-carbothioic acid root treatment. The threshold values for PR1a gene expression declined with a factor 10 to 100 in sitiens compared with WT plants. Thus, ABA appears to negatively modulate the salicylic acid-dependent defense pathway in tomato, which may be one of the mechanisms by which ABA levels determine susceptibility to B. cinerea. PMID:11842153

  20. Abscisic Acid Levels during Early Seed Development in Sechium edule Sw

    Science.gov (United States)

    Vernieri, Paolo; Perata, Pierdomenico; Lorenzi, Roberto; Ceccarelli, Nello

    1989-01-01

    The time-course growth of single tissues in pollinated and unpollinated ovules of Sechium edule Sw. is described in relation to the endogenous levels of abscisic acid. Quantitation of abscisic acid (ABA) in the minute amounts of material obtained after ovule dissection has been performed by using a highly specific and sensitive solid-phase radioimmunoassay based on a monoclonal antibody raised against free (S)-ABA. While the absolute amount of ABA rises in both types of ovules, only in unpollinated ones does this leads to an increase in the hormone concentration. Infact in pollinated ovules the rapid growth following pollination prevents, through a dilution effect, the increase in ABA concentration. Growth patterns and endogenous ABA levels are similar for integuments and nucellus tissues either in pollinated or unpollinated ovules. It is suggested that the growth inhibition induced by the increase in ABA concentration after anthesis could be counteracted by the pollination triggered fast ovule growth. PMID:16667185

  1. Abscisic Acid Levels during Early Seed Development in Sechium edule Sw.

    Science.gov (United States)

    Vernieri, P; Perata, P; Lorenzi, R; Ceccarelli, N

    1989-12-01

    The time-course growth of single tissues in pollinated and unpollinated ovules of Sechium edule Sw. is described in relation to the endogenous levels of abscisic acid. Quantitation of abscisic acid (ABA) in the minute amounts of material obtained after ovule dissection has been performed by using a highly specific and sensitive solid-phase radioimmunoassay based on a monoclonal antibody raised against free (S)-ABA. While the absolute amount of ABA rises in both types of ovules, only in unpollinated ones does this leads to an increase in the hormone concentration. Infact in pollinated ovules the rapid growth following pollination prevents, through a dilution effect, the increase in ABA concentration. Growth patterns and endogenous ABA levels are similar for integuments and nucellus tissues either in pollinated or unpollinated ovules. It is suggested that the growth inhibition induced by the increase in ABA concentration after anthesis could be counteracted by the pollination triggered fast ovule growth.

  2. Abscisic Acid Regulates Auxin Homeostasis in Rice Root Tips to Promote Root Hair Elongation

    Directory of Open Access Journals (Sweden)

    Tao Wang

    2017-06-01

    Full Text Available Abscisic acid (ABA plays an essential role in root hair elongation in plants, but the regulatory mechanism remains to be elucidated. In this study, we found that exogenous ABA can promote rice root hair elongation. Transgenic rice overexpressing SAPK10 (Stress/ABA-activated protein kinase 10 had longer root hairs; rice plants overexpressing OsABIL2 (OsABI-Like 2 had attenuated ABA signaling and shorter root hairs, suggesting that the effect of ABA on root hair elongation depends on the conserved PYR/PP2C/SnRK2 ABA signaling module. Treatment of the DR5-GUS and OsPIN-GUS lines with ABA and an auxin efflux inhibitor showed that ABA-induced root hair elongation depends on polar auxin transport. To examine the transcriptional response to ABA, we divided rice root tips into three regions: short root hair, long root hair and root tip zones; and conducted RNA-seq analysis with or without ABA treatment. Examination of genes involved in auxin transport, biosynthesis and metabolism indicated that ABA promotes auxin biosynthesis and polar auxin transport in the root tip, which may lead to auxin accumulation in the long root hair zone. Our findings shed light on how ABA regulates root hair elongation through crosstalk with auxin biosynthesis and transport to orchestrate plant development.

  3. Abscisic acid pathway involved in the regulation of watermelon fruit ripening and quality trait evolution

    OpenAIRE

    Wang, Yanping; Guo, Shaogui; Tian, Shouwei; Zhang, Jie; Ren, Yi; Sun, Honghe; Gong, Guoyi; Zhang, Haiying; Xu, Yong

    2017-01-01

    Watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai) is a non-climacteric fruit. The modern sweet-dessert watermelon is the result of years of cultivation and selection for fruits with desirable qualities. To date, the mechanisms of watermelon fruit ripening, and the role of abscisic acid (ABA) in this process, has not been well understood. We quantified levels of free and conjugated ABA contents in the fruits of cultivated watermelon (97103; C. lanatus subsp. vulgaris), semi-wild germplas...

  4. Abscisic acid is not necessary for gravitropism in primary roots of Zea mays

    Science.gov (United States)

    Moore, R.

    1990-01-01

    Primary roots of Zea mays L. cv. Tx 5855 treated with fluridone are strongly graviresponsive, but have undetectable levels of abscisic acid (ABA). Primary roots of the carotenoid-deficient w-3, vp-5, and vp-7 mutants of Z. mays are also graviresponsive despite having undetectable amounts of ABA. Graviresponsive roots of untreated and wild-type seedlings contain 286 to 317 ng ABA g-1 f. wt, respectively. These results indicate that ABA is not necessary for root gravicurvature.

  5. Immunoaffinity chromatography of abscisic acid combined with electrospray liquid chromatography–mass spectrometry

    Czech Academy of Sciences Publication Activity Database

    Hradecká, Veronika; Novák, Ondřej; Havlíček, Libor; Strnad, Miroslav

    2007-01-01

    Roč. 847, č. 2 (2007), s. 162-173 ISSN 1570-0232 R&D Projects: GA MŠk(CZ) LC06034; GA AV ČR IBS5038351 Institutional research plan: CEZ:AV0Z50380511 Source of funding: V - iné verejné zdroje ; V - iné verejné zdroje Keywords : abscisic acid * immunoaffinity chromatography * liquid chromatography-mass spectrometry Subject RIV: ED - Physiology Impact factor: 2.935, year: 2007

  6. Abscisic acid, gibberellins and brassinosteroids in Kelpak (R), a commercial seaweed extract made from Ecklonia maxima

    Czech Academy of Sciences Publication Activity Database

    Stirk, W. A.; Tarkowská, Danuše; Turečková, Veronika; Strnad, Miroslav; van Staden, J.

    2014-01-01

    Roč. 26, č. 1 (2014), s. 561-567 ISSN 0921-8971 R&D Projects: GA MŠk LK21306; GA ČR GA206/09/1284; GA MŠk(CZ) LO1204 Grant - others:GA MŠk(CZ) ED0007/01/01 Program:ED Institutional support: RVO:61389030 Keywords : Abscisic acid * Agricultural biostimulant * Brassinosteroids Subject RIV: EF - Botanics Impact factor: 2.559, year: 2014

  7. Auxin-Induced Ethylene Triggers Abscisic Acid Biosynthesis and Growth Inhibition1

    Science.gov (United States)

    Hansen, Hauke; Grossmann, Klaus

    2000-01-01

    The growth-inhibiting effects of indole-3-acetic acid (IAA) at high concentration and the synthetic auxins 7-chloro-3-methyl-8-quinolinecarboxylic acid (quinmerac), 2-methoxy-3,6-dichlorobenzoic acid (dicamba), 4-amino-3,6,6-trichloropicolinic acid (picloram), and naphthalene acetic acid, were investigated in cleavers (Galium aparine). When plants were root treated with 0.5 mm IAA, shoot epinasty and inhibition of root and shoot growth developed during 24 h. Concomitantly, 1-aminocyclopropane-1-carboxylic acid (ACC) synthase activity, and ACC and ethylene production were transiently stimulated in the shoot tissue within 2 h, followed by increases in immunoreactive (+)-abscisic acid (ABA) and its precursor xanthoxal (xanthoxin) after 5 h. After 24 h of treatment, levels of xanthoxal and ABA were elevated up to 2- and 24-fold, relative to control, respectively. In plants treated with IAA, 7-chloro-3-methyl-8-quinolinecarboxylic acid, naphthalene acetic acid, 2-methoxy-3,6-dichlorobenzoic acid, and 4-amino-3,6,6-trichloropicolinic acid, levels of ethylene, ACC, and ABA increased in close correlation with inhibition of shoot growth. Aminoethoxyvinyl-glycine and cobalt ions, which inhibit ethylene synthesis, decreased ABA accumulation and growth inhibition, whereas the ethylene-releasing ethephon promoted ABA levels and growth inhibition. In accordance, tomato mutants defective in ethylene perception (never ripe) did not produce the xanthoxal and ABA increases and growth inhibition induced by auxins in wild-type plants. This suggests that auxin-stimulated ethylene triggers ABA accumulation and the consequent growth inhibition. Reduced catabolism most probably did not contribute to ABA increase, as indicated by immunoanalyses of ABA degradation and conjugation products in shoot tissue and by pulse experiments with [3H]-ABA in cell suspensions of G. aparine. In contrast, studies using inhibitors of ABA biosynthesis (fluridone, naproxen, and tungstate), ABA

  8. Characterization of major ripening events during softening in grape: turgor, sugar accumulation, abscisic acid metabolism, colour development, and their relationship with growth

    Science.gov (United States)

    Castellarin, Simone D.; Gambetta, Gregory A.; Wada, Hiroshi; Krasnow, Mark N.; Cramer, Grant R.; Peterlunger, Enrico; Shackel, Kenneth A.; Matthews, Mark A.

    2016-01-01

    Along with sugar accumulation and colour development, softening is an important physiological change during the onset of ripening in fruits. In this work, we investigated the relationships among major events during softening in grape (Vitis vinifera L.) by quantifying elasticity in individual berries. In addition, we delayed softening and inhibited sugar accumulation using a mechanical growth-preventing treatment in order to identify processes that are sugar and/or growth dependent. Ripening processes commenced on various days after anthesis, but always at similarly low elasticity and turgor. Much of the softening occurred in the absence of other changes in berry physiology investigated here. Several genes encoding key cell wall-modifying enzymes were not up-regulated until softening was largely completed, suggesting softening may result primarily from decreases in turgor. Similarly, there was no decrease in solute potential, increase in sugar concentration, or colour development until elasticity and turgor were near minimum values, and these processes were inhibited when berry growth was prevented. Increases in abscisic acid occurred early during softening and in the absence of significant expression of the V. vinifera 9-cis-epoxycarotenoid dioxygenases. However, these increases were coincident with decreases in the abscisic acid catabolite diphasic acid, indicating that initial increases in abscisic acid may result from decreases in catabolism and/or exogenous import. These data suggest that softening, decreases in turgor, and increases in abscisic acid represent some of the earliest events during the onset of ripening. Later, physical growth, further increases in abscisic acid, and the accumulation of sugar are integral for colour development. PMID:26590311

  9. Sucrose Loading in Isolated Veins of Pisum sativum: Regulation by Abscisic Acid, Gibberellic Acid, and Cell Turgor 1

    Science.gov (United States)

    Estruch, Juan José; Peretó, Juli G.; Vercher, Yolanda; Beltrán, José Pío

    1989-01-01

    Enzymatically isolated vein networks from mature pea (Pisum sativum L. cv Alaska) leaves were employed to investigate the properties of sucrose loading and the effect of phytohormones and cell turgor on this process. The sucrose uptake showed two components: a saturable and a first-order kinetics system. The high affinity system (Km, 3.3 millimolar) was located at the plasmalemma (p-chloromercuriphenylsulfonic acid and orthovanadate sensitivity). Further characterization of this system, including pH dependence and effects of energy metabolism inhibitors, supported the H+-sugar symport concept for sucrose loading. Within a physiological range (0.1-100 micromolar) and after 90 min, abscisic acid (ABA) inhibited and gibberellic acid (GA3) promoted 1 millimolar sucrose uptake. These responses were partially (ABA) or totally (GA3) turgor-dependent. In experiments of combined hormonal treatments, ABA counteracted the GA3 positive effects on sucrose uptake. The abolishment of these responses by p-chloromercuriphenylsulfonic acid and experiments on proton flux suggest that both factors (cell turgor and hormones) are modulating the H+ ATPase plasmalemma activity. The results are discussed in terms of their physiological relevance. Images Figure 1 PMID:16667007

  10. Effect of Abscisic Acid on Accumulation of Five Active Components in Root of Glycyrrhiza uralensis

    Directory of Open Access Journals (Sweden)

    Jing Qiao

    2017-11-01

    Full Text Available Licorice is one of the most generally used herbal medicines in the world; however, wild licorice resources have decreased drastically. Cultivated Glycyrrhiza uralensis Fischer are the main source of licorice at present, but the content of main active components in cultivated G. uralensis are lower than in wild G. uralensis. Therefore, the production of high-quality cultivated G. uralensis is an urgent issue for the research and production fields. In this study, the content of five active components and seven endogenous phytohormones in cultivated G. uralensis (two-year-old were determined by high-performance liquid chromatography (HPLC and enzyme-linked immunosorbent assay (ELISA, respectively. Furthermore, different concentrations (25–200 mg/L of exogenous abscisic acid (ABA were sprayed on the leaves of G. uralensis in the fast growing period. Results showed that ABA, zeatin riboside (ZR, and dihydrozeatin riboside (DHZR had strong correlation with active components. In addition, the content of five active components increased remarkably after ABA treatment. Our results indicate that ABA is significantly related to the accumulation of active components in G. uralensis, and the application of exogenous ABA at the proper concentration is able to promote the accumulation of main components in G. uralensis.

  11. Priming effect of abscisic acid on alkaline stress tolerance in rice (Oryza sativa L.) seedlings.

    Science.gov (United States)

    Wei, Li-Xing; Lv, Bing-Sheng; Wang, Ming-Ming; Ma, Hong-Yuan; Yang, Hao-Yu; Liu, Xiao-Long; Jiang, Chang-Jie; Liang, Zheng-Wei

    2015-05-01

    Saline-alkaline stress is characterized by high salinity and high alkalinity (high pH); alkaline stress has been shown to be the primary factor inhibiting rice seedling growth. In this study, we investigated the potential priming effect of abscisic acid (ABA) on tolerance of rice seedlings to alkaline stress simulated by Na2CO3. Seedlings were pretreated with ABA at concentrations of 0 (control), 10, and 50 μM by root-drench for 24 h and then transferred to a Na2CO3 solution that did not contain ABA. Compared to control treatment, pretreatment with ABA substantially improved the survival rate of rice seedlings and increased biomass accumulation after 7 days under the alkaline condition. ABA application at 10 μM also alleviated the inhibitory effects of alkaline stress on the total root length and root surface area. Physiologically, ABA increased relative water content (RWC) and decreased cell membrane injury degree (MI) and Na(+)/K(+) ratios. In contrast, fluridone (an ABA biosynthesis inhibitor) decreased the RWC and increased MI in shoots under the alkaline conditions. These data suggest that ABA has a potent priming effect on the adaptive response to alkaline stress in rice and may be useful for improving rice growth in saline-alkaline paddy fields. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  12. Karrikins delay soybean seed germination by mediating abscisic acid and gibberellin biogenesis under shaded conditions

    Science.gov (United States)

    Meng, Yongjie; Chen, Feng; Shuai, Haiwei; Luo, Xiaofeng; Ding, Jun; Tang, Shengwen; Xu, Shuanshuan; Liu, Jianwei; Liu, Weiguo; Du, Junbo; Liu, Jiang; Yang, Feng; Sun, Xin; Yong, Taiwen; Wang, Xiaochun; Feng, Yuqi; Shu, Kai; Yang, Wenyu

    2016-01-01

    Karrikins (KAR) are a class of signal compounds, discovered in wildfire smoke, which affect seed germination. Currently, numerous studies have focused on the model plant Arabidopsis in the KAR research field, rather than on crops. Thus the regulatory mechanisms underlying KAR regulation of crop seed germination are largely unknown. Here, we report that KAR delayed soybean seed germination through enhancing abscisic acid (ABA) biosynthesis, while impairing gibberellin (GA) biogenesis. Interestingly, KAR only retarded soybean seed germination under shaded conditions, rather than under dark and white light conditions, which differs from in Arabidopsis. Phytohormone quantification showed that KAR enhanced ABA biogenesis while impairing GA biosynthesis during the seed imbibition process, and subsequently, the ratio of active GA4 to ABA was significantly reduced. Further qRT-PCR analysis showed that the transcription pattern of genes involved in ABA and GA metabolic pathways are consistent with the hormonal measurements. Finally, fluridone, an ABA biogenesis inhibitor, remarkably rescued the delayed-germination phenotype of KAR-treatment; and paclobutrazol, a GA biosynthesis inhibitor, inhibited soybean seed germination. Taken together, these evidences suggest that KAR inhibit soybean seed germination by mediating the ratio between GA and ABA biogenesis. PMID:26902640

  13. Homologous Recombination Defective Arabidopsis Mutants Exhibit Enhanced Sensitivity to Abscisic Acid.

    Directory of Open Access Journals (Sweden)

    Sujit Roy

    Full Text Available Abscisic acid (ABA acts as an important plant hormone in regulating various aspects of plant growth and developmental processes particularly under abiotic stress conditions. An increased ABA level in plant cells inhibits DNA replication and cell division, causing plant growth retardation. In this study, we have investigated the effects of ABA on the growth responses of some major loss-of-function mutants of DNA double-stand break (DSB repair genes in Arabidopsis during seed germination and early stages of seedling growth for understanding the role of ABA in the induction of genome instability in plants. A comparative analysis of ABA sensitivity of wild-type Arabidopsis and the knockout mutant lines related to DSB sensors, including atatm, atatr, the non-homologous end joining (NHEJ pathway genes, and mutants related to homologous recombination (HR pathway genes showed relatively enhanced sensitivity of atatr and HR-related mutants to ABA treatment. The expression levels of HR-related genes were increased in wild-type Arabidopsis (Col-0 during seed germination and early stages of seedling growth. Immunoblotting experiments detected phosphorylation of histone H2AX in wild-type (Col-0 and DSB repair gene mutants after ABA treatment, indicating the activation of DNA damage response due to ABA treatment. Analyses of DSB repair kinetics using comet assay under neutral condition have revealed comparatively slower DSB repair activity in HR mutants. Overall, our results have provided comprehensive information on the possible effect of ABA on DNA repair machinery in plants and also indicated potential functional involvement of HR pathway in repairing ABA induced DNA damage in Arabidopsis.

  14. Influence of exogenously applied abscisic acid on carotenoid content and water uptake in flowers of the tea plant (Camellia sinensis).

    Science.gov (United States)

    Baldermann, Susanne; Yang, Ziyin; Sakai, Miwa; Fleischmann, Peter; Morita, Akio; Todoroki, Yasushi; Watanabe, Naoharu

    2013-05-01

    Carotenoids are a major class of plant pigments and fulfill many functions in different organisms that either produce or consume them. Although the color of the stamina of tea (Camellia sinensis) flowers is clearly due to the presence of carotenoids, the carotenoid profile and content remain to be discovered. We investigated the carotenoid profile of tea flowers and determined changes in concentrations over the floral development. The flowers contained oxygenated xanthophylls such as neoxanthin, lutein and zeaxanthin, as well as the hydrocarbons β-carotene and α-carotene. Flowers of the tea plant contain to vegetables comparable amounts of carotenoids. The content of 9'-cis-epoxycarotenoids, which serve as abscisic acid precursors, as well as changes in concentration of abscisic acid were studied. The concentrations of carotenoids decreased whereas the abscisic acid content increased over the floral development. Exogenously applied S-abscisic acid affected water uptake, flower opening and carotenoid accumulation. In summary, this paper reports, for the first time, the carotenoid profile and content of tea flowers. The study revealed that carotenoids in tea flowers are an interesting target in respect of possible applications of tea flower extracts as well as biological functions of abscisic acid during floral development. © 2012 Society of Chemical Industry.

  15. Effect of the winter wheat cheyenne 5A substituted chromosome on dynamics of abscisic acid and cytokinins in freezing-sensitive Chinese spring genetic background

    Czech Academy of Sciences Publication Activity Database

    Kalapos, S.; Novák, A.; Dobrev, Petre; Vítámvás, P.; Marincs, F.; Galiba, G.; Vaňková, Radomíra

    2017-01-01

    Roč. 8, NOV 29 (2017), č. článku 2033. ISSN 1664-462X R&D Projects: GA ČR(CZ) GA17-06613S; GA MZe QJ1530373 Institutional support: RVO:61389030 Keywords : Abscisic acid * Cold treatment * Cytokinin * Freezing tolerance * Gene expression * Phytohormones * Triticum aestivum Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 4.298, year: 2016

  16. The effect of radiation on growth and abscisic acid in wheat seedlings

    International Nuclear Information System (INIS)

    Degani, N.; Itai, C.

    1978-01-01

    Irradiation of dry wheat grains with various doses (10, 30, 70 krads) of gamma rays, increased abscisic acid (ABA) concentrations in roots and leaves of 5 day old seedlings. The ABA concentration was higher in leaves than in roots. Growth inhibition was proportional to irradiation dose and ABA concentration, and roots were more inhibited than leaves. When irradiation (1 and 2 krads) were applied 24 hr after initiation of germination, ABA concentration was higher in roots than in leaves. It is suggested that radiation-induced ABA may upset the hormonal balance during germination, which may affect growth. (author)

  17. Abscisic acid-cytokinin antagonism modulates resistance against pseudomonas syringae in Tobacco

    DEFF Research Database (Denmark)

    Grosskinsky, Dominik Kilian; van der Graaff, Eric; Roitsch, Thomas Georg

    2014-01-01

    Phytohormones are known as essential regulators of plant defenses, with ethylene, jasmonic acid, and salicylic acid as the central immunity backbone, while other phytohormones have been demonstrated to interact with this. Only recently, a function of the classic phytohormone cytokinin in plant...... immunity has been described in Arabidopsis, rice, and tobacco. Although interactions of cytokinins with salicylic acid and auxin have been indicated, the complete network of cytokinin interactions with other immunity-relevant phytohormones is not yet understood. Therefore, we studied the interaction...... of kinetin and abscisic acid as a negative regulator of plant immunity to modulate resistance in tobacco against Pseudomonas syringae. By analyzing infection symptoms, pathogen proliferation, and accumulation of the phytoalexin scopoletin as a key mediator of kinetin-induced resistance in tobacco...

  18. Stomatal response of an anisohydric grapevine cultivar to evaporative demand, available soil moisture and abscisic acid.

    Science.gov (United States)

    Rogiers, Suzy Y; Greer, Dennis H; Hatfield, Jo M; Hutton, Ron J; Clarke, Simon J; Hutchinson, Paul A; Somers, Anthony

    2012-03-01

    Stomatal responsiveness to evaporative demand (air vapour pressure deficit (VPD)) ranges widely between species and cultivars, and mechanisms for stomatal control in response to VPD remain obscure. The interaction of irrigation and soil moisture with VPD on stomatal conductance is particularly difficult to predict, but nevertheless is critical to instantaneous transpiration and vulnerability to desiccation. Stomatal sensitivity to VPD and soil moisture was investigated in Semillon, an anisohydric Vitis vinifera L. variety whose leaf water potential (Ψ(l)) is frequently lower than that of other grapevine varieties grown under similar conditions in the warm grape-growing regions of Australia. A survey of Semillon vines across seven vineyards revealed that, regardless of irrigation treatment, midday Ψ(l) was dependent on not only soil moisture but VPD at the time of measurement. Predawn Ψ(l) was more closely correlated to not only soil moisture in dry vineyards but to night-time VPD in drip-irrigated vineyards, with incomplete rehydration during high night-time VPD. Daytime stomatal conductance was low only under severe plant water deficits, induced by extremes in dry soil. Stomatal response to VPD was inconsistent across irrigation regime; however, in an unirrigated vineyard, stomatal sensitivity to VPD-the magnitude of stomatal response to VPD-was heightened under dry soils. It was also found that stomatal sensitivity was proportional to the magnitude of stomatal conductance at a reference VPD of 1kPa. Exogenous abscisic acid (ABA) applied to roots of Semillon vines growing in a hydroponic system induced stomatal closure and, in field vines, petiole xylem sap ABA concentrations rose throughout the morning and were higher in vines with low Ψ(l). These data indicate that despite high stomatal conductance of this anisohydric variety when grown in medium to high soil moisture, increased concentrations of ABA as a result of very limited soil moisture may augment

  19. Abscisic Acid Induces Rapid Reductions in Mesophyll Conductance to Carbon Dioxide.

    Directory of Open Access Journals (Sweden)

    Giuseppe Sorrentino

    Full Text Available The rate of photosynthesis (A of plants exposed to water deficit is a function of stomatal (gs and mesophyll (gm conductance determining the availability of CO2 at the site of carboxylation within the chloroplast. Mesophyll conductance often represents the greatest impediment to photosynthetic uptake of CO2, and a crucial determinant of the photosynthetic effects of drought. Abscisic acid (ABA plays a fundamental role in signalling and co-ordination of plant responses to drought; however, the effect of ABA on gm is not well-defined. Rose, cherry, olive and poplar were exposed to exogenous ABA and their leaf gas exchange parameters recorded over a four hour period. Application with ABA induced reductions in values of A, gs and gm in all four species. Reduced gm occurred within one hour of ABA treatment in three of the four analysed species; indicating that the effect of ABA on gm occurs on a shorter timescale than previously considered. These declines in gm values associated with ABA were not the result of physical changes in leaf properties due to altered turgor affecting movement of CO2, or caused by a reduction in the sub-stomatal concentration of CO2 (Ci. Increased [ABA] likely induces biochemical changes in the properties of the interface between the sub-stomatal air-space and mesophyll layer through the actions of cooporins to regulate the transport of CO2. The results of this study provide further evidence that gm is highly responsive to fluctuations in the external environment, and stress signals such as ABA induce co-ordinated modifications of both gs and gm in the regulation of photosynthesis.

  20. Ammonium regulates embryogenic potential in Cucurbita pepo through pH-mediated changes in endogenous auxin and abscisic acid

    Czech Academy of Sciences Publication Activity Database

    Pěnčík, Aleš; Turečková, Veronika; Paulisić, S.; Rolčík, Jakub; Strnad, Miroslav; Mihaljević, S.

    2015-01-01

    Roč. 122, č. 1 (2015), s. 89-100 ISSN 0167-6857 Grant - others:GA MŠk(CZ) ED0007/01/01 Program:ED Institutional support: RVO:61389030 Keywords : Abscisic acid * Ammonium * Indole-3-acetic acid Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.390, year: 2015

  1. Alleviation of Osmotic Stress Effects by Exogenous Application of Salicylic or Abscisic Acid on Wheat Seedlings

    Directory of Open Access Journals (Sweden)

    Katarzyna Cyganek

    2013-06-01

    Full Text Available The aim of the study was to assess the role of salicylic acid (SA and abscisic acid (ABA in osmotic stress tolerance of wheat seedlings. This was accomplished by determining the impact of the acids applied exogenously on seedlings grown under osmotic stress in hydroponics. The investigation was unique in its comprehensiveness, examining changes under osmotic stress and other conditions, and testing a number of parameters simultaneously. In both drought susceptible (SQ1 and drought resistant (CS wheat cultivars, significant physiological and biochemical changes were observed upon the addition of SA (0.05 mM or ABA (0.1 μM to solutions containing half-strength Hoagland medium and PEG 6000 (−0.75 MPa. The most noticeable result of supplementing SA or ABA to the medium (PEG + SA and PEG + ABA was a decrease in the length of leaves and roots in both cultivars. While PEG treatment reduced gas exchange parameters, chlorophyll content in CS, and osmotic potential, and conversely, increased lipid peroxidation, soluble carbohydrates in SQ1, proline content in both cultivars and total antioxidants activity in SQ1, PEG + SA or PEG + ABA did not change the values of these parameters. Furthermore, PEG caused a two-fold increase of endogenous ABA content in SQ1 and a four-fold increase in CS. PEG + ABA increased endogenous ABA only in SQ1, whereas PEG + SA caused a greater increase of ABA content in both cultivars compared to PEG. In PEG-treated plants growing until the harvest, a greater decrease of yield components was observed in SQ1 than in CS. PEG + SA, and particularly PEG + ABA, caused a greater increase of these yield parameters in CS compared to SQ1. In conclusion, SA and ABA ameliorate, particularly in the tolerant wheat cultivar, the harmful effects and after effects of osmotic stress induced by PEG in hydroponics through better osmotic adjustment achieved by an increase in proline and carbohydrate content as well as by an increase in antioxidant

  2. Genomic profiling of exogenous abscisic acid-responsive microRNAs in tomato (Solanum lycopersicum).

    Science.gov (United States)

    Cheng, Hai-Yang; Wang, Yan; Tao, Xiang; Fan, Yan-Fen; Dai, Ya; Yang, Hong; Ma, Xin-Rong

    2016-06-03

    Plant microRNAs (miRNAs) are involved in various biological pathways and stress responses as negative regulators at the posttranscriptional level. Abscisic acid (ABA) is a key signaling molecule that mediates plant stress response by activating many stress-related genes. Although some miRNAs in plants are previously identified to respond to ABA, a comprehensive profile of ABA-responsive miRNAs has not yet been elucidated. Here, we identified miRNAs responding to exogenous application of ABA, and their predicted target genes in the model plant organism tomato (Solanum lycopersicum). Deep sequencing of small RNAs from ABA-treated and untreated tomatoes revealed that miRNAs can be up- or down-regulated upon treatment with ABA. A total of 1067 miRNAs were detected (including 365 known and 702 candidate novel miRNAs), of those, 416 miRNAs which had an abundance over two TPM (transcripts per million) were selected for differential expression analysis. We identified 269 (180 known and 89 novel) miRNAs that respond to exogenous ABA treatment with a change in expression level of |log2FC|≥0.25. 136 of these miRNAs (90 known and 46 novel) were expressed at significantly different levels |log2FC|≥1 between treatments. Furthermore, stem-loop RT-PCR was applied to validate the RNA-seq data. Target prediction and analysis of the corresponding ABA-responsive transcriptome data uncovered that differentially expressed miRNAs are involved in condition stress and pathogen resistance, growth and development. Among them, approximately 90 miRNAs were predicted to target transcription factors and pathogen resistance genes. Some miRNAs had functional overlap in biotic and abiotic stress. Most of these miRNAs were down-regulated following exposure to exogenous ABA, while their related target genes were inversely up-regulated, which is consistent with their negative regulatory role in gene expression. Exogenous ABA application influences the composition and expression level of tomato mi

  3. Abscisic Acid and the Maturation of Cacao Embryos in Vitro 1

    Science.gov (United States)

    Pence, Valerie Creaser

    1992-01-01

    Abscisic acid (ABA) was tested for its ability to affect development of immature zygotic embryos of cacao (Theobroma cacao) in vitro, by adding exogenous ABA, fluridone, or mefluidide to cultured embryos. Endogenous ABA levels, measured by enzyme-linked immunosorbent assay, were increased by exogenous ABA or by culture on sucrose increasing to 21%, and were decreased by fluridone and, to a lesser extent, by mefluidide. The effects of these on maturation were measured as effects on anthocyanins, lipids, and fatty acid saturation, all of which increase with maturation of the cacao embryo. Maturation was stimulated by increasing sucrose and, to a lesser degree, the addition of ABA, but decreasing endogenous ABA by treating with fluridone significantly inhibited all maturation parameters. Although desiccation tolerance does not develop in cacao embryos, these results suggest that ABA and sucrose are both needed for the initiation of events associated with maturation in vitro. PMID:16668805

  4. Endogenous cytokinins, auxins and abscisic acid in Ulva fasciata (Chlorophyta) and Dictyota humifusa (Phaeophyta): towards understanding their biosynthesis and homoeostasis

    Czech Academy of Sciences Publication Activity Database

    Stirk, W.A.; Novák, Ondřej; Hradecká, Veronika; Pěnčík, Aleš; Rolčík, Jakub; Strnad, Miroslav; van Staden, J.

    2009-01-01

    Roč. 44, č. 2 (2009), s. 231-240 ISSN 0967-0262 R&D Projects: GA ČR GA206/05/0894 Institutional research plan: CEZ:AV0Z50380511 Keywords : abscisic acid * auxins * cytokinins Subject RIV: BO - Biophysics Impact factor: 1.556, year: 2009 www.informaworld.com/smpp/content~content=a911046981

  5. Effect of exogenous abscisic acid on stomatal characteristics during acclimation of in vitro-grown tobacco (Nicotiana tabacum L.) plants

    Czech Academy of Sciences Publication Activity Database

    Tichá, I.; Pospíšilová, Jana

    2008-01-01

    Roč. 133, - (2008), P09-131 ISSN 0031-9317 R&D Projects: GA ČR GA522/07/0227 Institutional research plan: CEZ:AV0Z50380511 Keywords : fluorescence * abscisic acid * antioxidative enzymes Subject RIV: ED - Physiology Impact factor: 2.334, year: 2008

  6. Hormonal regulation of seed development and germination in tomato : studies on abscisic acid- and gibberellin-deficient mutants

    NARCIS (Netherlands)

    Groot, S.P.C.

    1987-01-01

    The role of endogenous gibberellins (GAs) and abscisic acid (ABA) in seed development and germination of tomato, was studied with the use of GA- and/or ABA-deficient mutants.

    GAs are indispensable for the development of fertile flowers. Fertility of GA-deficient flowers is restored

  7. Effect of abscisic acid on stomatal opening in isolated epidermal strips of abi mutants of Arabidopsis thaliana

    NARCIS (Netherlands)

    Roelfsema, MRG; Prins, HBA

    1995-01-01

    Abscisic acid-insensitive mutants of Arabidopsis thaliana L. var. Landsberg erecta were selected for their decreased sensitivity to ABA during germination. Two of these mutants, abi-1 and abi-2, display a wilty phenotype as adult plants, indicating disturbed water relations. Experiments were

  8. Spatio-temporal changes in endogenous abscisic acid contents during etiolated growth and photomorphogenesis in tomato seedlings

    Czech Academy of Sciences Publication Activity Database

    Humplík, Jan; Turečková, Veronika; Fellner, Martin; Bergougnoux, V.

    2015-01-01

    Roč. 10, č. 8 (2015), č. článku e1039213. ISSN 1559-2316 R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : arabidopsis seedlings * blue-light * phytochromes * germination * metabolism * dormancy * barley * seeds * abscisic acid * blue-light * etiolated growth * photomorphogenesis * tomato Subject RIV: EB - Genetics ; Molecular Biology

  9. Cytokinins and Abscisic Acid Act Antagonistically in the Regulation of the Bud Outgrowth Pattern by Light Intensity

    Directory of Open Access Journals (Sweden)

    Adrien Corot

    2017-10-01

    Full Text Available Bud outgrowth is a key process in the elaboration of yield and visual quality in rose crops. Although light intensity is well known to affect bud outgrowth, little is known on the mechanisms involved in this regulation. The objective of this work was to test if the control of bud outgrowth pattern along the stem by photosynthetic photon flux density (PPFD is mediated by sugars, cytokinins and/or abscisic acid in intact rose plants. Rooted cuttings of Rosa hybrida ‘Radrazz’ were grown in growth chambers under high PPFD (530 μmol m-2 s-1 until the floral bud visible stage. Plants were then either placed under low PPFD (90 μmol m-2 s-1 or maintained under high PPFD. Bud outgrowth inhibition by low PPFD was associated with lower cytokinin and sugar contents and a higher abscisic acid content in the stem. Interestingly, cytokinin supply to the stem restored bud outgrowth under low PPFD. On the other hand, abscisic acid supply inhibited outgrowth under high PPFD and antagonized bud outgrowth stimulation by cytokinins under low PPFD. In contrast, application of sugars did not restore bud outgrowth under low PPFD. These results suggest that PPFD regulation of bud outgrowth in rose involves a signaling pathway in which cytokinins and abscisic acid play antagonistic roles. Sugars can act as nutritional and signaling compounds and may be involved too, but do not appear as the main regulator of the response to PPFD.

  10. ATAF1 transcription factor directly regulates abscisic acid biosynthetic gene NCED3 in Arabidopsis thaliana

    DEFF Research Database (Denmark)

    Jensen, Michael Krogh; Lindemose, Søren; De Masi, Federico

    2013-01-01

    ATAF1, an Arabidopsis thaliana NAC transcription factor, plays important roles in plant adaptation to environmental stress and development. To search for ATAF1 target genes, we used protein binding microarrays and chromatin-immunoprecipitation (ChIP). This identified T[A,C,G]CGT[A,G] and TT......[A,C,G]CGT as ATAF1 consensus binding sequences. Co-expression analysis across publicly available microarray experiments identified 25 genes co-expressed with ATAF1. The promoter regions of ATAF1 co-expressors were significantly enriched for ATAF1 binding sites, and TTGCGTA was identified in the promoter of the key...... abscisic acid (ABA) phytohormone biosynthetic gene NCED3. ChIP-qPCR and expression analysis showed that ATAF1 binding to the NCED3 promoter correlated with increased NCED3 expression and ABA hormone levels. These results indicate that ATAF1 regulates ABA biosynthesis....

  11. Developmental priming of stomatal sensitivity to abscisic acid by leaf microclimate.

    Science.gov (United States)

    Pantin, Florent; Renaud, Jeanne; Barbier, François; Vavasseur, Alain; Le Thiec, Didier; Rose, Christophe; Bariac, Thierry; Casson, Stuart; McLachlan, Deirdre H; Hetherington, Alistair M; Muller, Bertrand; Simonneau, Thierry

    2013-09-23

    Plant water loss and CO2 uptake are controlled by valve-like structures on the leaf surface known as stomata. Stomatal aperture is regulated by hormonal and environmental signals. We show here that stomatal sensitivity to the drought hormone abscisic acid (ABA) is acquired during leaf development by exposure to an increasingly dryer atmosphere in the rosette plant Arabidopsis. Young leaves, which develop in the center of the rosette, do not close in response to ABA. As the leaves increase in size, they are naturally exposed to increasingly dry air as a consequence of the spatial arrangement of the leaves, and this triggers the acquisition of ABA sensitivity. Interestingly, stomatal ABA sensitivity in young leaves is rapidly restored upon water stress. These findings shed new light on how plant architecture and stomatal physiology have coevolved to optimize carbon gain against water loss in stressing environments. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. A new look at stress: abscisic acid patterns and dynamics at high-resolution.

    Science.gov (United States)

    Jones, Alexander M

    2016-04-01

    Abscisic acid (ABA) is a key phytohormone promoting abiotic stress tolerance as well as developmental processes such as seed dormancy. A spatiotemporal map of ABA concentrations would greatly advance our understanding of the cell type and timing of ABA action. Organ and tissue-level ABA measurements, as well as indirect in vivo measurements such as cell-specific transcriptional analysis of ABA metabolic enzymes and ABA-responsive promoters, have all contributed to current views of the localization and timing of ABA accumulations. Recently developed Förster resonance energy transfer (FRET) biosensors for ABA that sense ABA levels directly promise to add unprecedented resolution to in vivo ABA spatiotemporal mapping and expand our knowledge of the mechanisms controlling ABA levels in space and time. © 2015 Carnegie Institution for Science New Phytologist © 2015 New Phytologist Trust.

  13. Exogenous abscisic acid application during grain filling in winter wheat improves cold tolerance of offspring's seedlings

    DEFF Research Database (Denmark)

    Li, X.; Cai, J.; Liu, Fulai

    2014-01-01

    Low temperature seriously depresses seed germination and seedling growth in winter wheat (Triticum aestivum L.). In this study, wheat plants were sprayed with abscisic acid (ABA) and fluridone (inhibitor of ABA biosynthesis) at 19 days after anthesis (DAA) and repeated at 26 DAA. The seeds of those...... plants were harvested, and seed germination and offspring's seedling growth under low temperature were evaluated. The results showed that exogenous ABA application decreased seed weight and slightly reduced seed set and seed number per spike. Under low temperature, seeds from ABA-treated plants showed...... reduced germination rate, germination index, growth of radicle and coleoptile, amylase activity and depressed starch degradation as compared with seeds from non-ABA-treated plants; however, activities of the antioxidant enzymes in both germinating seeds and seedling were enhanced from those exposed...

  14. ABSCISIC ACID EFFECTS ON WATER AND PHOTOSYNTHETIC CHARACTERISTICS OF TWO ECOTYPES OF Atriplex halimus L.

    Directory of Open Access Journals (Sweden)

    Y. Bidai

    2016-05-01

    Full Text Available The aim of this study is to compare the water and photosynthetic characteristics of two xerophilic ecotypes of Atriplex halimus (L.. Seeds collected from two different sites Djelfa and Oran are germinated in controlled greenhouse. After 6 months, the plantlets were treated 21 days with increasing concentrations of abscisic acid (0M, 10-6 M and 10-3 M. The results show that ecotype of Djelfa reduced water loss through transpiration because of high stomatal resistance. Consequently the content of chlorophyll a and b decrease significantly compared to Oran ecotype which show an increase of the osmotic potential and relative water content. Osmotic adjustment to reduce dehydration and maintain a good photosynthesis seems efficient in Oran ecotype.

  15. Sustained exposure to abscisic acid enhances the colonization potential of the mutualist fungus Piriformospora indica on Arabidopsis thaliana roots.

    Science.gov (United States)

    Peskan-Berghöfer, Tatjana; Vilches-Barro, Amaya; Müller, Teresa M; Glawischnig, Erich; Reichelt, Michael; Gershenzon, Jonathan; Rausch, Thomas

    2015-11-01

    Root colonization by the beneficial fungus Piriformospora indica is controlled by plant innate immunity, but factors that channel this interaction into a mutualistic relationship are not known. We have explored the impact of abscisic acid (ABA) and osmotic stress on the P. indica interaction with Arabidopsis thaliana. The activation of plant innate immunity in roots was determined by measuring the concentration of the phytoalexin camalexin and expression of transcription factors regulating the biosynthesis of tryptophan-related defence metabolites. Furthermore, the impact of the fungus on the content of ABA, salicylic acid, jasmonic acid (JA) and JA-related metabolites was examined. We demonstrated that treatment with exogenous ABA or the ABA analogue pyrabactin increased fungal colonization efficiency without impairment of plant fitness. Concomitantly, ABA-deficient mutants of A. thaliana (aba1-6 and aba2-1) were less colonized, while plants exposed to moderate stress were more colonized than corresponding controls. Sustained exposure to ABA attenuated expression of transcription factors MYB51, MYB122 and WRKY33 in roots upon P. indica challenge or chitin treatment, and prevented an increase in camalexin content. The results indicate that ABA can strengthen the interaction with P. indica as a consequence of its impact on plant innate immunity. Consequently, ABA will be relevant for the establishment and outcome of the symbiosis under stress conditions. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  16. Abscisic-acid-dependent basic leucine zipper (bZIP) transcription factors in plant abiotic stress.

    Science.gov (United States)

    Banerjee, Aditya; Roychoudhury, Aryadeep

    2017-01-01

    One of the major causes of significant crop loss throughout the world is the myriad of environmental stresses including drought, salinity, cold, heavy metal toxicity, and ultraviolet-B (UV-B) rays. Plants as sessile organisms have evolved various effective mechanism which enable them to withstand this plethora of stresses. Most of such regulatory mechanisms usually follow the abscisic-acid (ABA)-dependent pathway. In this review, we have primarily focussed on the basic leucine zipper (bZIP) transcription factors (TFs) activated by the ABA-mediated signalosome. Upon perception of ABA by specialized receptors, the signal is transduced via various groups of Ser/Thr kinases, which phosphorylate the bZIP TFs. Following such post-translational modification of TFs, they are activated so that they bind to specific cis-acting sequences called abscisic-acid-responsive elements (ABREs) or GC-rich coupling elements (CE), thereby influencing the expression of their target downstream genes. Several in silico techniques have been adopted so far to predict the structural features, recognize the regulatory modification sites, undergo phylogenetic analyses, and facilitate genome-wide survey of TF under multiple stresses. Current investigations on the epigenetic regulation that controls greater accessibility of the inducible regions of DNA of the target gene to the bZIP TFs exclusively under stress situations, along with the evolved stress memory responses via genomic imprinting mechanism, have been highlighted. The potentiality of overexpression of bZIP TFs, either in a homologous or in a heterologous background, in generating transgenic plants tolerant to various abiotic stressors have also been addressed by various groups. The present review will provide a coherent documentation on the functional characterization and regulation of bZIP TFs under multiple environmental stresses, with the major goal of generating multiple-stress-tolerant plant cultivars in near future.

  17. α-Ketol linolenic acid (KODA) application affects endogenous abscisic acid, jasmonic acid and aromatic volatiles in grapes infected by a pathogen (Glomerella cingulata).

    Science.gov (United States)

    Wang, Shanshan; Saito, Takanori; Ohkawa, Katsuya; Ohara, Hitoshi; Shishido, Masahiro; Ikeura, Hiromi; Takagi, Kazuteru; Ogawa, Shigeyuki; Yokoyama, Mineyuki; Kondo, Satoru

    2016-03-15

    Effects of α-ketol linolenic acid (KODA) application on endogenous abscisic acid (ABA), jasmonic acid (JA), and aromatic volatiles were investigated in 'Kyoho' grapes (Vitis labrusca×Vitis vinifera) infected by a pathogen (Glomerella cingulata). The expressions of 9-cis-epoxycarotenoid dioxygenase (VvNCED1), ABA 8'-hydroxylase (VvCYP707A1), lipoxygenase (VvLOX), and allene oxide synthase (VvAOS) were also examined. The grape berries were dipped in 0.1mM KODA solution before inoculation with the pathogen and stored at 25°C for 12 days. The development of infection was significantly suppressed upon KODA treatment. Endogenous ABA, JA and phaseic acid (PA) were induced in inoculated berries. KODA application before inoculation increased endogenous ABA, PA and JA through the activation of VvNCED1, VvCYP707A1 and VvAOS genes, respectively. In addition, terpenes, methyl salicylate (Me-SA) and C6-aldehydes such as (E)-2-hexenal and cis-3-hexenal associated with fungal resistance also increased in KODA-treated berries during storage. These results suggest that the synergistic effect of JA, ABA, and some aromatic volatiles induced by KODA application may provide resistance to pathogen infection in grape berries. Copyright © 2016 Elsevier GmbH. All rights reserved.

  18. Effect of Exogenous Abscisic Acid and Methyl Jasmonate on Anthocyanin Composition, Fatty Acids, and Volatile Compounds of Cabernet Sauvignon (Vitis vinifera L. Grape Berries

    Directory of Open Access Journals (Sweden)

    Yan-Lun Ju

    2016-10-01

    Full Text Available The anthocyanin composition, fatty acids, and volatile aromas are important for Cabernet Sauvignon grape quality. This study evaluated the effect of exogenous abscisic acid (ABA and methyl jasmonate (MeJA on the anthocyanin composition, fatty acids, lipoxygenase activity, and the volatile compounds of Cabernet Sauvignon grape berries. Exogenous ABA and MeJA improved the content of total anthocyanins (TAC and individual anthocyanins. Lipoxygenase (LOX activity also increased after treatment. Furthermore, 16 fatty acids were detected. The linoleic acid concentration gradually increased with ABA concentration. The fatty acid content decreased with increasing MeJA concentration and then increased again, with the exception of linoleic acid. After exogenous ABA and MeJA treatment, the C6 aroma content increased significantly. Interestingly, the exogenous ABA and MeJA treatments improved mainly the content of 1-hexanol, hexanal, and 2-heptanol. These results provide insight into the effect of plant hormones on wine grapes, which is useful for grape quality improvement.

  19. An abscisic acid-independent oxylipin pathway controls stomatal closure and immune defense in Arabidopsis.

    Science.gov (United States)

    Montillet, Jean-Luc; Leonhardt, Nathalie; Mondy, Samuel; Tranchimand, Sylvain; Rumeau, Dominique; Boudsocq, Marie; Garcia, Ana Victoria; Douki, Thierry; Bigeard, Jean; Laurière, Christiane; Chevalier, Anne; Castresana, Carmen; Hirt, Heribert

    2013-01-01

    Plant stomata function in innate immunity against bacterial invasion and abscisic acid (ABA) has been suggested to regulate this process. Using genetic, biochemical, and pharmacological approaches, we demonstrate that (i) the Arabidopsis thaliana nine-specific-lipoxygenase encoding gene, LOX1, which is expressed in guard cells, is required to trigger stomatal closure in response to both bacteria and the pathogen-associated molecular pattern flagellin peptide flg22; (ii) LOX1 participates in stomatal defense; (iii) polyunsaturated fatty acids, the LOX substrates, trigger stomatal closure; (iv) the LOX products, fatty acid hydroperoxides, or reactive electrophile oxylipins induce stomatal closure; and (v) the flg22-mediated stomatal closure is conveyed by both LOX1 and the mitogen-activated protein kinases MPK3 and MPK6 and involves salicylic acid whereas the ABA-induced process depends on the protein kinases OST1, MPK9, or MPK12. Finally, we show that the oxylipin and the ABA pathways converge at the level of the anion channel SLAC1 to regulate stomatal closure. Collectively, our results demonstrate that early biotic signaling in guard cells is an ABA-independent process revealing a novel function of LOX1-dependent stomatal pathway in plant immunity.

  20. An abscisic acid-independent oxylipin pathway controls stomatal closure and immune defense in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Jean-Luc Montillet

    Full Text Available Plant stomata function in innate immunity against bacterial invasion and abscisic acid (ABA has been suggested to regulate this process. Using genetic, biochemical, and pharmacological approaches, we demonstrate that (i the Arabidopsis thaliana nine-specific-lipoxygenase encoding gene, LOX1, which is expressed in guard cells, is required to trigger stomatal closure in response to both bacteria and the pathogen-associated molecular pattern flagellin peptide flg22; (ii LOX1 participates in stomatal defense; (iii polyunsaturated fatty acids, the LOX substrates, trigger stomatal closure; (iv the LOX products, fatty acid hydroperoxides, or reactive electrophile oxylipins induce stomatal closure; and (v the flg22-mediated stomatal closure is conveyed by both LOX1 and the mitogen-activated protein kinases MPK3 and MPK6 and involves salicylic acid whereas the ABA-induced process depends on the protein kinases OST1, MPK9, or MPK12. Finally, we show that the oxylipin and the ABA pathways converge at the level of the anion channel SLAC1 to regulate stomatal closure. Collectively, our results demonstrate that early biotic signaling in guard cells is an ABA-independent process revealing a novel function of LOX1-dependent stomatal pathway in plant immunity.

  1. Heat-stable proteins and abscisic acid action in barley aleurone cells

    International Nuclear Information System (INIS)

    Jacobsen, J.V.; Shaw, D.C.

    1989-01-01

    [ 35 S]Methionine labeling experiments showed that abscisic acid (ABA) induced the synthesis of at least 25 polypeptides in mature barley (Hordeum vulgare) aleurone cells. The polypeptides were not secreted. Whereas most of the proteins extracted from aleurone cells were coagulated by heating to 100 degree C for 10 minutes, most of the ABA-induced polypeptides remained in solution (heat-stable). ABA had little effect on the spectrum of polypeptides that were synthesized and secreted by aleurone cells, and most of these secreted polypeptides were also heat-stable. Coomassie blue staining of sodium dodecyl sulfate polyacrylamide gels indicated that ABA-induced polypeptides already occurred in high amounts in mature aleurone layers having accumulated during grain development. About 60% of the total protein extracted from mature aleurone was heat stable. Amino acid analyses of total preparations of heat-stable and heat-labile proteins showed that, compared to heat-labile proteins, heat-stable intracellular proteins were characterized by higher glutamic acid/glutamine (Glx) and glycine levels and lower levels of neutral amino acids. Secreted heat-stable proteins were rich in Glx and proline. The possibilities that the accumulation of the heat-stable polypeptides during grain development is controlled by ABA and that the function of these polypeptides is related to their abundance and extraordinary heat stability are considered

  2. An Abscisic Acid-Independent Oxylipin Pathway Controls Stomatal Closure and Immune Defense in Arabidopsis

    Science.gov (United States)

    Mondy, Samuel; Tranchimand, Sylvain; Rumeau, Dominique; Boudsocq, Marie; Garcia, Ana Victoria; Douki, Thierry; Bigeard, Jean; Laurière, Christiane; Chevalier, Anne; Castresana, Carmen; Hirt, Heribert

    2013-01-01

    Plant stomata function in innate immunity against bacterial invasion and abscisic acid (ABA) has been suggested to regulate this process. Using genetic, biochemical, and pharmacological approaches, we demonstrate that (i) the Arabidopsis thaliana nine-specific-lipoxygenase encoding gene, LOX1, which is expressed in guard cells, is required to trigger stomatal closure in response to both bacteria and the pathogen-associated molecular pattern flagellin peptide flg22; (ii) LOX1 participates in stomatal defense; (iii) polyunsaturated fatty acids, the LOX substrates, trigger stomatal closure; (iv) the LOX products, fatty acid hydroperoxides, or reactive electrophile oxylipins induce stomatal closure; and (v) the flg22-mediated stomatal closure is conveyed by both LOX1 and the mitogen-activated protein kinases MPK3 and MPK6 and involves salicylic acid whereas the ABA-induced process depends on the protein kinases OST1, MPK9, or MPK12. Finally, we show that the oxylipin and the ABA pathways converge at the level of the anion channel SLAC1 to regulate stomatal closure. Collectively, our results demonstrate that early biotic signaling in guard cells is an ABA-independent process revealing a novel function of LOX1-dependent stomatal pathway in plant immunity. PMID:23526882

  3. P-HYDROXYPHENYLPYRUVATE DIOXYGENASE from Medicago sativa is involved in vitamin E biosynthesis and abscisic acid-mediated seed germination

    Science.gov (United States)

    Jiang, Jishan; Chen, Zhihong; Ban, Liping; Wu, Yudi; Huang, Jianping; Chu, Jinfang; Fang, Shuang; Wang, Zan; Gao, Hongwen; Wang, Xuemin

    2017-01-01

    P-HYDROXYPHENYLPYRUVATE DIOXYGENASE (HPPD) is the first committed enzyme involved in the biosynthesis of vitamin E, and is characterized by catalyzing the conversion of p-hydroxyphenyl pyruvate (HPP) to homogentisic acid (HGA). Here, an HPPD gene was cloned from Medicago sativa L. and designated MsHPPD, which was expressed at high levels in alfalfa leaves. PEG 6000 (polyethylene glycol), NaCl, abscisic acid and salicylic acid were shown to significantly induce MsHPPD expression, especially in the cotyledons and root tissues. Overexpression of MsHPPD was found to significantly increase the level of β-tocotrienol and the total vitamin E content in Arabidopsis seeds. Furthermore, these transgenic Arabidopsis seeds exhibited an accelerated germination time, compared with wild-type seeds under normal conditions, as well as under NaCl and ABA treatments. Meanwhile, the expression level of several genes associated with ABA biosynthesis (NCED3, NCED5 and NCED9) and the ABA signaling pathway (RAB18, ABI3 and ABI5) were significantly down-regulated in MsHPPD-overexpressing transgenic lines, as well as the total free ABA content. Taken together, these results demonstrate that MsHPPD functions not only in the vitamin E biosynthetic pathway, but also plays a critical role in seed germination via affecting ABA biosynthesis and signaling. PMID:28084442

  4. P-HYDROXYPHENYLPYRUVATE DIOXYGENASE from Medicago sativa is involved in vitamin E biosynthesis and abscisic acid-mediated seed germination.

    Science.gov (United States)

    Jiang, Jishan; Chen, Zhihong; Ban, Liping; Wu, Yudi; Huang, Jianping; Chu, Jinfang; Fang, Shuang; Wang, Zan; Gao, Hongwen; Wang, Xuemin

    2017-01-13

    P-HYDROXYPHENYLPYRUVATE DIOXYGENASE (HPPD) is the first committed enzyme involved in the biosynthesis of vitamin E, and is characterized by catalyzing the conversion of p-hydroxyphenyl pyruvate (HPP) to homogentisic acid (HGA). Here, an HPPD gene was cloned from Medicago sativa L. and designated MsHPPD, which was expressed at high levels in alfalfa leaves. PEG 6000 (polyethylene glycol), NaCl, abscisic acid and salicylic acid were shown to significantly induce MsHPPD expression, especially in the cotyledons and root tissues. Overexpression of MsHPPD was found to significantly increase the level of β-tocotrienol and the total vitamin E content in Arabidopsis seeds. Furthermore, these transgenic Arabidopsis seeds exhibited an accelerated germination time, compared with wild-type seeds under normal conditions, as well as under NaCl and ABA treatments. Meanwhile, the expression level of several genes associated with ABA biosynthesis (NCED3, NCED5 and NCED9) and the ABA signaling pathway (RAB18, ABI3 and ABI5) were significantly down-regulated in MsHPPD-overexpressing transgenic lines, as well as the total free ABA content. Taken together, these results demonstrate that MsHPPD functions not only in the vitamin E biosynthetic pathway, but also plays a critical role in seed germination via affecting ABA biosynthesis and signaling.

  5. 1-Aminocyclopropane-1-carboxylic acid and abscisic acid during the germination of sugar beet (Beta vulgaris L.): a comparative study of fruits and seeds

    Czech Academy of Sciences Publication Activity Database

    Hermann, K.; Meinhard, J.; Dobrev, Petre; Linkies, A.; Pešek, Bedřich; Heß, B.; Macháčková, Ivana; Fischer, U.; Leubner-Metzger, G.

    2007-01-01

    Roč. 58, č. 11 (2007), s. 3047-3060 ISSN 0022-0957 Institutional research plan: CEZ:AV0Z50380511 Keywords : abscisic acid (ABA) * ABA 8'-hydroxylase (CYP707A) * 1-aminocyclopropane-1-carboxylic acid (ACC) Subject RIV: EF - Botanics Impact factor: 3.917, year: 2007

  6. Immunolocalization of endogenous indole-3-acetic acid and abscisic acid in the shoot internodes of Fargesia yunnanensis bamboo during development

    Science.gov (United States)

    Shuguang Wang; Yongpeng Ma; Chengbin Wan; Chungyun Hse; Todd F. Shupe; Yujun Wang; Changming. Wang

    2016-01-01

    The Bambusoideae subfamily includes the fastest-growing plants worldwide, as a consequence of fast internode elongation. However, few studies have evaluated the temporal and spatial distribution of endogenous hormones during internode elongation. In this paper, endogenous indole-3-acetic acid (IAA) and abscisic acid (ABA) were detected in different developmental...

  7. Conservation between higher plants and the moss Physcomitrella patens in response to the phytohormone abscisic acid: a proteomics analysis

    Directory of Open Access Journals (Sweden)

    Wang Xiaoqin

    2010-08-01

    Full Text Available Abstract Background The plant hormone abscisic acid (ABA is ubiquitous among land plants where it plays an important role in plant growth and development. In seeds, ABA induces embryogenesis and seed maturation as well as seed dormancy and germination. In vegetative tissues, ABA is a necessary mediator in the triggering of many of the physiological and molecular adaptive responses of the plant to adverse environmental conditions, such as desiccation, salt and cold. Results In this study, we investigated the influence of abscisic acid (ABA on Physcomitrella patens at the level of the proteome using two-dimensional gel electrophoresis (2-DE and liquid chromatography-tandem mass spectrometry (LC-MS/MS. Sixty-five protein spots showed changes in response to ABA treatment. Among them, thirteen protein spots were down-regulated; fifty-two protein spots were up-regulated including four protein spots which were newly induced. These proteins were involved in various functions, including material and energy metabolism, defense, protein destination and storage, transcription, signal transduction, cell growth/division, transport, and cytoskeleton. Specifically, most of the up-regulated proteins functioned as molecular chaperones, transcriptional regulators, and defense proteins. Detailed analysis of these up-regulated proteins showed that ABA could trigger stress and defense responses and protect plants from oxidative damage. Otherwise, three protein kinases involved in signal pathways were up-regulated suggesting that P. patens is sensitive to exogenous ABA. The down-regulated of the Rubisco small subunit, photosystem II oxygen-evolving complex proteins and photosystem assembly protein ycf3 indicated that photosynthesis of P. patens was inhibited by ABA treatment. Conclusion Proteome analysis techniques have been applied as a direct, effective, and reliable tool in differential protein expressions. Sixty-five protein spots showed differences in

  8. Comparative Transcriptome Analysis Reveals the Influence of Abscisic Acid on the Metabolism of Pigments, Ascorbic Acid and Folic Acid during Strawberry Fruit Ripening.

    Science.gov (United States)

    Li, Dongdong; Li, Li; Luo, Zisheng; Mou, Wangshu; Mao, Linchun; Ying, Tiejin

    2015-01-01

    A comprehensive investigation of abscisic acid (ABA) biosynthesis and its influence on other important phytochemicals is critical for understanding the versatile roles that ABA plays during strawberry fruit ripening. Using RNA-seq technology, we sampled strawberry fruit in response to ABA or nordihydroguaiaretic acid (NDGA; an ABA biosynthesis blocker) treatment during ripening and assessed the expression changes of genes involved in the metabolism of pigments, ascorbic acid (AsA) and folic acid in the receptacles. The transcriptome analysis identified a lot of genes differentially expressed in response to ABA or NDGA treatment. In particular, genes in the anthocyanin biosynthesis pathway were actively regulated by ABA, with the exception of the gene encoding cinnamate 4-hydroxylase. Chlorophyll degradation was accelerated by ABA mainly owing to the higher expression of gene encoding pheide a oxygenase. The decrease of β-carotene content was accelerated by ABA treatment and delayed by NDGA. A high negative correlation rate was found between ABA and β-carotene content, indicating the importance of the requirement for ABA synthesis during fruit ripening. In addition, evaluation on the folate biosynthetic pathway indicate that ABA might have minor function in this nutrient's biosynthesis process, however, it might be involved in its homeostasis. Surprisingly, though AsA content accumulated during fruit ripening, expressions of genes involved in its biosynthesis in the receptacles were significantly lower in ABA-treated fruits. This transcriptome analysis expands our understanding of ABA's role in phytochemical metabolism during strawberry fruit ripening and the regulatory mechanisms of ABA on these pathways were discussed. Our study provides a wealth of genetic information in the metabolism pathways and may be helpful for molecular manipulation in the future.

  9. Comparative Transcriptome Analysis Reveals the Influence of Abscisic Acid on the Metabolism of Pigments, Ascorbic Acid and Folic Acid during Strawberry Fruit Ripening.

    Directory of Open Access Journals (Sweden)

    Dongdong Li

    Full Text Available A comprehensive investigation of abscisic acid (ABA biosynthesis and its influence on other important phytochemicals is critical for understanding the versatile roles that ABA plays during strawberry fruit ripening. Using RNA-seq technology, we sampled strawberry fruit in response to ABA or nordihydroguaiaretic acid (NDGA; an ABA biosynthesis blocker treatment during ripening and assessed the expression changes of genes involved in the metabolism of pigments, ascorbic acid (AsA and folic acid in the receptacles. The transcriptome analysis identified a lot of genes differentially expressed in response to ABA or NDGA treatment. In particular, genes in the anthocyanin biosynthesis pathway were actively regulated by ABA, with the exception of the gene encoding cinnamate 4-hydroxylase. Chlorophyll degradation was accelerated by ABA mainly owing to the higher expression of gene encoding pheide a oxygenase. The decrease of β-carotene content was accelerated by ABA treatment and delayed by NDGA. A high negative correlation rate was found between ABA and β-carotene content, indicating the importance of the requirement for ABA synthesis during fruit ripening. In addition, evaluation on the folate biosynthetic pathway indicate that ABA might have minor function in this nutrient's biosynthesis process, however, it might be involved in its homeostasis. Surprisingly, though AsA content accumulated during fruit ripening, expressions of genes involved in its biosynthesis in the receptacles were significantly lower in ABA-treated fruits. This transcriptome analysis expands our understanding of ABA's role in phytochemical metabolism during strawberry fruit ripening and the regulatory mechanisms of ABA on these pathways were discussed. Our study provides a wealth of genetic information in the metabolism pathways and may be helpful for molecular manipulation in the future.

  10. Abscisic Acid content of senescing petals on cut rose flowers as affected by sucrose and water stress.

    Science.gov (United States)

    Borohov, A; Tirosh, T; Halevy, A H

    1976-08-01

    Leafless cut Superstar roses (Rosa hyb.) were kept in a 1% sucrose solution. During the first few days of treatment, the abscisic acid content and the water deficit in the petals was higher in treated flowers than in controls kept in water. Later and up to the termination of the flower's life, ABA content and water deficit values were lower in petals of sucrose-treated flowers than in controls. Water stress treatments resulted in higher water deficit values and higher ABA content of petals. An 8-day sucrose treatment following temporary water stress improved the quality of flowers and reduced the level of ABA in the petals. We conclude that the effect which sucrose has on the ABA content of rose petals is at least partly due to its effect on changes in water deficit in the petals. This happens in spite of the fact that rose petals have no stomata, and therefore, ABA is not involved in regulating water balance via the stomata.

  11. Ethylene limits abscisic acid- or soil drying-induced stomatal closure in aged wheat leaves.

    Science.gov (United States)

    Chen, Lin; Dodd, Ian C; Davies, William J; Wilkinson, Sally

    2013-10-01

    The mechanism of age-induced decreased stomatal sensitivity to abscisic acid (ABA) and soil drying has been explored here. Older, fully expanded leaves partly lost their ability to close stomata in response to foliar ABA sprays, and soil drying which stimulated endogenous ABA production, while young fully expanded leaves closed their stomata more fully. However, ABA- or soil drying-induced stomatal closure of older leaves was partly restored by pretreating plants with 1-methylcyclopropene (1-MCP), which can antagonize ethylene receptors, or by inoculating soil around the roots with the rhizobacterium Variovorax paradoxus 5C-2, which contains 1-aminocyclopropane-1-carboxylic acid (ACC)-deaminase. ACC (the immediate biosynthetic precursor of ethylene) sprays revealed higher sensitivity of stomata to ethylene in older leaves than younger leaves, despite no differences in endogenous ACC concentrations or ethylene emission. Taken together, these results indicate that the relative insensitivity of stomatal closure to ABA and soil drying in older leaves is likely due to altered stomatal sensitivity to ethylene, rather than ethylene production. To our knowledge, this is the first study to mechanistically explain diminished stomatal responses to soil moisture deficit in older leaves, and the associated reduction in leaf water-use efficiency. © 2013 John Wiley & Sons Ltd.

  12. Interplay between Carotenoids, Abscisic Acid and Jasmonate Guides the Compatible Rice-Meloidogyne graminicola Interaction

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    Tina Kyndt

    2017-06-01

    Full Text Available In this study, we have characterized the role of carotenoids and chlorophyll in the compatible interaction between the sedentary root knot nematode (RKN Meloidogyne graminicola and the monocot model plant rice (Oryza sativa. Previous transcriptome data showed a differential expression of carotenoid and chlorophyll biosynthesis genes in nematode-induced giant cells and gall tissue. Metabolite measurement showed that galls indeed accumulate chlorophyll a, b and carotenoids, as well as the hormone abscisic acid (ABA. When ABA was externally applied on rice plants, or when ABA-biosynthesis was inhibited, a significant increase in gall formation and nematode development was found, showing the complex role of ABA in this interaction. ABA application suppressed jasmonic acid (JA levels in the plants, while ABA-biosynthesis inhibition lead to increased JA levels confirming an antagonism between ABA and JA in rice roots. In addition, combined applications of ABA and JA showed that the ABA-effect can overcome JA-induced defense. Based on these observations, we hypothesized that the accumulation of chlorophyll and carotenoid precursors would be beneficial to nematode infection. Indeed, when chemically blocking the carotenoid biosynthesis pathway at different steps, which leads to differential accumulation of carotenoids and chlorophyll in the plants, a positive and clear link between accumulation of carotenoids and chlorophyll and rice susceptibility to RKN was detected.

  13. Functional convergence of oxylipin and abscisic acid pathways controls stomatal closure in response to drought.

    Science.gov (United States)

    Savchenko, Tatyana; Kolla, Venkat A; Wang, Chang-Quan; Nasafi, Zainab; Hicks, Derrick R; Phadungchob, Bpantamars; Chehab, Wassim E; Brandizzi, Federica; Froehlich, John; Dehesh, Katayoon

    2014-03-01

    Membranes are primary sites of perception of environmental stimuli. Polyunsaturated fatty acids are major structural constituents of membranes that also function as modulators of a multitude of signal transduction pathways evoked by environmental stimuli. Different stresses induce production of a distinct blend of oxygenated polyunsaturated fatty acids, "oxylipins." We employed three Arabidopsis (Arabidopsis thaliana) ecotypes to examine the oxylipin signature in response to specific stresses and determined that wounding and drought differentially alter oxylipin profiles, particularly the allene oxide synthase branch of the oxylipin pathway, responsible for production of jasmonic acid (JA) and its precursor 12-oxo-phytodienoic acid (12-OPDA). Specifically, wounding induced both 12-OPDA and JA levels, whereas drought induced only the precursor 12-OPDA. Levels of the classical stress phytohormone abscisic acid (ABA) were also mainly enhanced by drought and little by wounding. To explore the role of 12-OPDA in plant drought responses, we generated a range of transgenic lines and exploited the existing mutant plants that differ in their levels of stress-inducible 12-OPDA but display similar ABA levels. The plants producing higher 12-OPDA levels exhibited enhanced drought tolerance and reduced stomatal aperture. Furthermore, exogenously applied ABA and 12-OPDA, individually or combined, promote stomatal closure of ABA and allene oxide synthase biosynthetic mutants, albeit most effectively when combined. Using tomato (Solanum lycopersicum) and Brassica napus verified the potency of this combination in inducing stomatal closure in plants other than Arabidopsis. These data have identified drought as a stress signal that uncouples the conversion of 12-OPDA to JA and have revealed 12-OPDA as a drought-responsive regulator of stomatal closure functioning most effectively together with ABA.

  14. Exogenous application of abscisic acid may improve the growth and yield of sunflower hybrids under drought

    International Nuclear Information System (INIS)

    Hussain, S.; Iqbal, J.; Ibrahim, M.; Atta, S.; Ahmed, T.; Saleem, M.F.

    2014-01-01

    Sunflower genotypes perform differently under different water regimes. Drought stress at various growth stages drastically reduces the growth, development and yield of sunflower hybrids. However, exogenous application of abscisic acid helps in mitigating drought stress by improving growth, development and yield of sunflower. In the present study, three sunflower hybrids viz. DK-4040 (large stature), S-278 (medium stature) and SF-187 (short stature) were exposed to varied irrigation regimes and abscisic acid application schedule i.e. T1: four irrigations with schedule (25DAS, at bud, flower initiation and at achene formation) and with no ABA spray,T/sub 2/: three irrigations with schedule (25DAS, at flower initiation and at achene formation) and with no ABA spray, T/sub 3/: three irrigations with schedule (25DAS, at flower initiation and at achene formation) and with 8 mu MABA spray at bud initiation, T/sub 4/: three irrigations with schedule (25DAS, at bud initiation and at achene formation) and with no ABA spray, T/sub 5/: three irrigations with schedule (25DAS, at bud initiation and at achene formation) and with 8 mu M ABA spray at flower initiation. Experiment was laid out in Randomized Complete Design with factorial arrangement having three replications. ABA application at bud or at flower initiation under drought stress helped in mitigating the detrimental effects by improving growth and yield of sunflower hybrids. Enhancement in drought tolerance of sunflower genotypes was better when ABA was applied at bud initiation stage than that of at flower initiation stage under drought. Improvements in head diameter, achenes per head, 1000-achene weight, achene yield, oil yield, biological yield, harvest index, leaf area index and crop growth rate was recorded. Sunflower hybrid DK-4040 showed more improvement in drought tolerance byfoliar application of ABA under water deficit stress than that of the SF-187 and S-278. It is suggested that sunflower hybrid DK 4040

  15. Proline and Abscisic Acid Content in Droughted Corn Plant Inoculated with Azospirillum sp. and Arbuscular Mycorrhizae Fungi

    Directory of Open Access Journals (Sweden)

    NOVRI YOULA KANDOWANGKO

    2009-03-01

    Full Text Available Plants that undergo drought stress perform a physiological response such as accumulation of proline in the leaves and increased content abscisic acid. A research was conducted to study proline and abscisic acid (ABA content on drought-stressed corn plant with Azospirillum sp. and arbuscular mycorrhizae fungi (AMF inoculated at inceptisol soil from Bogor, West Java. The experiments were carried out in a green house from June up to September 2003, using a factorial randomized block design. In pot experiments, two factors were assigned, i.e. inoculation with Azospirillum (0, 0.50, 1.00, 1.50 ml/pot and inoculation with AMF Glomus manihotis (0, 12.50, 25.00, 37.50 g/pot. The plants were observed during tasseling up to seed filling periods. Results of experiments showed that the interaction between Azospirillum sp. and AMF was synergistically increased proline, however it decreased ABA.

  16. Effects of abscisic acid on ethylene biosynthesis and perception in Hibiscus rosa-sinensis L. flower development

    Science.gov (United States)

    Trivellini, Alice; Ferrante, Antonio; Vernieri, Paolo; Serra, Giovanni

    2011-01-01

    The effect of the complex relationship between ethylene and abscisic acid (ABA) on flower development and senescence in Hibiscus rosa-sinensis L. was investigated. Ethylene biosynthetic (HrsACS and HrsACO) and receptor (HrsETR and HrsERS) genes were isolated and their expression evaluated in three different floral tissues (petals, style–stigma plus stamens, and ovaries) of detached buds and open flowers. This was achieved through treatment with 0.1 mM 1-aminocyclopropane-1-carboxylic acid (ACC) solution, 500 nl l−1 methylcyclopropene (1-MCP), and 0.1 mM ABA solution. Treatment with ACC and 1-MCP confirmed that flower senescence in hibiscus is ethylene dependent, and treatment with exogenous ABA suggested that ABA may play a role in this process. The 1-MCP impeded petal in-rolling and decreased ABA content in detached open flowers after 9 h. This was preceded by an earlier and sequential increase in ABA content in 1-MCP-treated petals and style–stigma plus stamens between 1 h and 6 h. ACC treatment markedly accelerated flower senescence and increased ethylene production after 6 h and 9 h, particularly in style–stigma plus stamens. Ethylene evolution was positively correlated in these floral tissues with the induction of the gene expression of ethylene biosynthetic and receptor genes. Finally, ABA negatively affected the ethylene biosynthetic pathway and tissue sensitivity in all flower tissues. Transcript abundance of HrsACS, HrsACO, HrsETR, and HrsERS was reduced by exogenous ABA treatment. This research underlines the regulatory effect of ABA on the ethylene biosynthetic and perception machinery at a physiological and molecular level when inhibitors or promoters of senescence are exogenously applied. PMID:21841180

  17. Proteogenomic analysis reveals alternative splicing and translation as part of the abscisic acid response in Arabidopsis seedlings.

    Science.gov (United States)

    Zhu, Fu-Yuan; Chen, Mo-Xian; Ye, Neng-Hui; Shi, Lu; Ma, Kai-Long; Yang, Jing-Fang; Cao, Yun-Ying; Zhang, Youjun; Yoshida, Takuya; Fernie, Alisdair R; Fan, Guang-Yi; Wen, Bo; Zhou, Ruo; Liu, Tie-Yuan; Fan, Tao; Gao, Bei; Zhang, Di; Hao, Ge-Fei; Xiao, Shi; Liu, Ying-Gao; Zhang, Jianhua

    2017-08-01

    In eukaryotes, mechanisms such as alternative splicing (AS) and alternative translation initiation (ATI) contribute to organismal protein diversity. Specifically, splicing factors play crucial roles in responses to environment and development cues; however, the underlying mechanisms are not well investigated in plants. Here, we report the parallel employment of short-read RNA sequencing, single molecule long-read sequencing and proteomic identification to unravel AS isoforms and previously unannotated proteins in response to abscisic acid (ABA) treatment. Combining the data from the two sequencing methods, approximately 83.4% of intron-containing genes were alternatively spliced. Two AS types, which are referred to as alternative first exon (AFE) and alternative last exon (ALE), were more abundant than intron retention (IR); however, by contrast to AS events detected under normal conditions, differentially expressed AS isoforms were more likely to be translated. ABA extensively affects the AS pattern, indicated by the increasing number of non-conventional splicing sites. This work also identified thousands of unannotated peptides and proteins by ATI based on mass spectrometry and a virtual peptide library deduced from both strands of coding regions within the Arabidopsis genome. The results enhance our understanding of AS and alternative translation mechanisms under normal conditions, and in response to ABA treatment. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

  18. Effects of abscisic acid and brassinolide on photosynthetic characteristics of Leymus chinensis from Songnen Plain grassland in Northeast China.

    Science.gov (United States)

    Hu, Yong-Jun; Shi, Lian-Xuan; Sun, Wei; Guo, Ji-Xun

    2013-12-01

    It has been well demonstrated that plant growth regulators have important functions in multiple physiological processes. ABA and BR play crucial roles in response of crops to stresses. Photosynthetic capacity of Leymus. chinensis treated by various concentrations of ABA and BR in combination was determined. Further more, the mechanisms of ABA and BR treatments and potential for recovery of saline-alkali grasslands were discussed. Abscisic acid (ABA) and brassinolide (BR) affected leaf gas exchange, growth and biomass of L. chinensis. The application of ABA and BR mixtures, especially that of 0.01 mM ABA and 2 × 10 -4  mM BR, increased the net photosynthetic rate, stomatal conductance, water use efficiency, the maximum net photosynthetic rate, light-saturated rate, leaf respiration rate, the maximum RUBP carboxylation rate, the maximum electron transport rate, the maximum triose-phosphate utilization, carboxylation efficiency and the quantum efficiency of PSII and subsequently enhanced density, height and biomass in L. chinensis. We also observed reduction in the light compensation and saturation points following the application of ABA and BR treatments. We concluded that proper use of plant growth regulators can enhance the plant growth and productivity on the Songnen grassland, which is particularly important for the improvement of saline - alkaline grassland and the yield of grazing lands.

  19. The plant cuticle is required for osmotic stress regulation of abscisic acid biosynthesis and osmotic stress tolerance in Arabidopsis

    KAUST Repository

    Wang, Zhenyu

    2011-05-01

    Osmotic stress activates the biosynthesis of abscisic acid (ABA). One major step in ABA biosynthesis is the carotenoid cleavage catalyzed by a 9-cis epoxycarotenoid dioxygenase (NCED). To understand the mechanism for osmotic stress activation of ABA biosynthesis, we screened for Arabidopsis thaliana mutants that failed to induce the NCED3 genee xpression in response to osmotic stress treatments. The ced1 (for 9-cis epoxycarotenoid dioxy genase defective 1) mutant isolated in this study showed markedly reduced expression of NCED3 in response to osmotic stress (polyethylene glycol)treatments compared with the wild type. Other ABA biosynthesis genes are also greatly reduced in ced1 under osmotic stress. ced1 mutant plants are very sensitive to even mild osmotic stress. Map-based cloning revealed unexpectedly thatCED1 encodes a putative a/b hydrolase domain-containing protein and is allelic to the BODYGUARD gene that was recently shown to be essential for cuticle biogenesis. Further studies discovered that other cut in biosynthesis mutants are also impaired in osmotic stress induction of ABA biosynthesis genes and are sensitive to osmotic stress. Our work demonstrates that the cuticle functions not merely as a physical barrier to minimize water loss but also mediates osmotic stress signaling and tolerance by regulating ABA biosynthesis and signaling. © 2011 American Society of Plant Biologists. All rights reserved.

  20. Cytokinin, auxin, and abscisic acid dynamics during flower development in white and red currants infected with Blackcurrant reversion virus

    Czech Academy of Sciences Publication Activity Database

    Gaudinová, Alena; Malbeck, Jiří; Dobrev, Petre; Kubelková, Darina; Špak, Josef; Vaňková, Radomíra

    2009-01-01

    Roč. 73, č. 6 (2009), s. 119-125 ISSN 0885-5765 R&D Projects: GA MŠk 1P05OC052; GA MŠk OC09084 Institutional research plan: CEZ:AV0Z50380511; CEZ:AV0Z50510513 Keywords : Full blossom disease * Cytokinin * Auxin * Abscisic acid Subject RIV: ED - Physiology Impact factor: 1.407, year: 2009

  1. Abscinazole-E3M, a practical inhibitor of abscisic acid 8?-hydroxylase for improving drought tolerance

    OpenAIRE

    Takeuchi, Jun; Okamoto, Masanori; Mega, Ryosuke; Kanno, Yuri; Ohnishi, Toshiyuki; Seo, Mitsunori; Todoroki, Yasushi

    2016-01-01

    Abscisic acid (ABA) is an essential phytohormone that regulates plant water use and drought tolerance. However, agricultural applications of ABA have been limited because of its rapid inactivation in plants, which involves hydroxylation of ABA by ABA 8?-hydroxylase (CYP707A). We previously developed a selective inhibitor of CYP707A, (?)-Abz-E2B, by structurally modifying S-uniconazole, which functions as an inhibitor of CYP707A and as a gibberellin biosynthetic enzyme. However, its synthetic ...

  2. Gibberellin-to-abscisic acid balances govern development and differentiation of the nucellar projection of barley grains

    Czech Academy of Sciences Publication Activity Database

    Weier, D.; Thiel, J.; Kohl, S.; Tarkowská, Danuše; Strnad, Miroslav; Schaarschmidt, S.; Weschke, W.; Weber, H.; Hause, B.

    2014-01-01

    Roč. 65, č. 18 (2014), s. 5291-5304 ISSN 0022-0957 R&D Projects: GA MŠk LK21306 Grant - others:GA MŠk(CZ) ED0007/01/01 Program:ED Institutional support: RVO:61389030 Keywords : Assimilate transfer * barley endosperm * gibberellin-to- abscisic acid balances Subject RIV: EF - Botanics Impact factor: 5.526, year: 2014

  3. Proteome analysis of Norway maple (Acer platanoides L. seeds dormancy breaking and germination: influence of abscisic and gibberellic acids

    Directory of Open Access Journals (Sweden)

    Pawłowski Tomasz A

    2009-05-01

    Full Text Available Abstract Background Seed dormancy is controlled by the physiological or structural properties of a seed and the external conditions. It is induced as part of the genetic program of seed development and maturation. Seeds with deep physiological embryo dormancy can be stimulated to germinate by a variety of treatments including cold stratification. Hormonal imbalance between germination inhibitors (e.g. abscisic acid and growth promoters (e.g. gibberellins is the main cause of seed dormancy breaking. Differences in the status of hormones would affect expression of genes required for germination. Proteomics offers the opportunity to examine simultaneous changes and to classify temporal patterns of protein accumulation occurring during seed dormancy breaking and germination. Analysis of the functions of the identified proteins and the related metabolic pathways, in conjunction with the plant hormones implicated in seed dormancy breaking, would expand our knowledge about this process. Results A proteomic approach was used to analyse the mechanism of dormancy breaking in Norway maple seeds caused by cold stratification, and the participation of the abscisic (ABA and gibberellic (GA acids. Forty-four proteins showing significant changes were identified by mass spectrometry. Of these, eight spots were identified as water-responsive, 18 spots were ABA- and nine GA-responsive and nine spots were regulated by both hormones. The classification of proteins showed that most of the proteins associated with dormancy breaking in water were involved in protein destination. Most of the ABA- and GA-responsive proteins were involved in protein destination and energy metabolism. Conclusion In this study, ABA was found to mostly down-regulate proteins whereas GA up-regulated proteins abundance. Most of the changes were observed at the end of stratification in the germinated seeds. This is the most active period of dormancy breaking when seeds pass from the quiescent

  4. Xanthophylls and abscisic acid biosynthesis in water-stressed bean leaves

    Energy Technology Data Exchange (ETDEWEB)

    Li, Y.; Walton, D.C.

    1987-12-01

    Experiments were designed to obtain evidence about the possible role of xanthophylls as abscisic acid (ABA) precursors in water-stressed leaves of Phaseolus vularis L. Leaves were exposed to /sup 14/CO/sub 2/ and the specific activities of several major leaf xanthophylls and stress-induced ABA were determined after a chase in /sup 12/CO/sub 2/ for varying periods of time. The ABA specific radioactivities were about 30 to 70% of that of lutein and violaxanthin regardless of the chase period. The specific activity of neoxanthin, however, was only about 15% of that of ABA. The effects of fluridone on xanthophyll and ABA levels and the extent of labeling of both from /sup 14/CO/sub 2/ were determined. Fluridone did not inhibit the accumulation of ABA when leaves were stressed once, although subsequent stresses in the presence of fluridone did lead to a reduced ABA accumulation. The incorporation of /sup 14/C from /sup 14/CO/sub 2/ into ABA and the xanthophylls was inhibited by fluridone and to about the same extent. The incorporation of /sup 18/O into ABA from violaxanthin which had been labeled in situ by means of the violaxanthin cycle was measured. The results indicated that a portion of the ABA accumulated during stress was formed from violaxanthin which had been labeled with /sup 18/O. The results of these experiments are consistent with a preformed xanthophyll(s) as the major ABA precursor in water-stressed bean leaves.

  5. Tetraploid Rangpur lime rootstock increases drought tolerance via enhanced constitutive root abscisic acid production.

    Science.gov (United States)

    Allario, Thierry; Brumos, Javier; Colmenero-Flores, Jose M; Iglesias, Domingo J; Pina, Jose A; Navarro, Luis; Talon, Manuel; Ollitrault, Patrick; Morillon, Raphaël

    2013-04-01

    Whole-genome duplication, or polyploidy, is common in many plant species and often leads to better adaptation to adverse environmental condition. However, little is known about the physiological and molecular determinants underlying adaptation. We examined the drought tolerance in diploid (2x) and autotetraploid (4x) clones of Rangpur lime (Citrus limonia) rootstocks grafted with 2x Valencia Delta sweet orange (Citrus sinensis) scions, named V/2xRL and V/4xRL, respectively. Physiological experiments to study root-shoot communication associated with gene expression studies in roots and leaves were performed. V/4xRL was much more tolerant to water deficit than V/2xRL. Gene expression analysis in leaves and roots showed that more genes related to the response to water stress were differentially expressed in V/2xRL than in V/4xRL. Prior to the stress, when comparing V/4xRL to V/2xRL, V/4xRL leaves had lower stomatal conductance and greater abscisic acid (ABA) content. In roots, ABA content was higher in V/4xRL and was associated to a greater expression of drought responsive genes, including CsNCED1, a pivotal regulatory gene of ABA biosynthesis. We conclude that tetraploidy modifies the expression of genes in Rangpur lime citrus roots to regulate long-distance ABA signalling and adaptation to stress. © 2012 Blackwell Publishing Ltd.

  6. Overexpression of the transcription factor NF-YC9 confers abscisic acid hypersensitivity in Arabidopsis.

    Science.gov (United States)

    Bi, Chao; Ma, Yu; Wang, Xiao-Fang; Zhang, Da-Peng

    2017-11-01

    Nuclear factor Y (NF-Y) family proteins are involved in many developmental processes and responses to environmental cues in plants, but whether and how they regulate phytohormone abscisic acid (ABA) signaling need further studies. In the present study, we showed that over-expression of the NF-YC9 gene confers ABA hypersensitivity in both the early seedling growth and stomatal response, while down-regulation of NF-YC9 does not affect ABA response in these processes. We also showed that over-expression of the NF-YC9 gene confers salt and osmotic hypersensitivity in early seedling growth, which is likely to be directly associated with the ABA hypersensitivity. Further, we observed that NF-YC9 physically interacts with the ABA-responsive bZIP transcription factor ABA-INSENSITIVE5 (ABI5), and facilitates the function of ABI5 to bind and activate the promoter of a target gene EM6. Additionally, NF-YC9 up-regulates expression of the ABI5 gene in response to ABA. These findings show that NF-YC9 may be involved in ABA signaling as a positive regulator and likely functions redundantly together with other NF-YC members, and support the model that the NF-YC9 mediates ABA signaling via targeting to and aiding the ABA-responsive transcription factors such as ABI5.

  7. Microarray Analysis of Transcriptional Responses to Abscisic Acid and Salt Stress in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Yucheng Wang

    2013-05-01

    Full Text Available Abscisic acid (ABA plays a crucial role in plant responses to abiotic stress. To investigate differences in plant responses to salt and ABA stimulus, differences in gene expression in Arabidopsis in response to salt and ABA were compared using an Agilent oligo microarray. A total of 144 and 139 genes were significantly up- and downregulated, respectively, under NaCl stress, while 406 and 381 genes were significantly up- and downregulated, respectively, under ABA stress conditions. In addition, 31 genes were upregulated by both NaCl and ABA stresses, and 23 genes were downregulated by these stressors, suggesting that these genes may play similar roles in plant responses to salt and ABA stress. Gene ontology (GO analysis revealed four subgroups of genes, including genes in the GO categories “Molecular transducer activity”, “Growth”, “Biological adhesion” and “Pigmentation”, which were expressed in response to ABA stress but not NaCl stress. In addition, genes that play specific roles during salt or ABA stress were identified. Our results may help elucidate differences in the response of plants to salt and ABA stress.

  8. Role of abscisic acid (aba) in modulating the responses of two apple rootstocks to drought stress

    International Nuclear Information System (INIS)

    Zhang, L.; Li, X.; Li, B.; Han, M.; Liu, F.; Zhang, L.; Zheng, P.

    2014-01-01

    Drought stress is considered as the main limiting factor for apple (Malus domestica L.) production in some semi-arid areas of China. In this study, we investigated the modulation role of abscisic acid (ABA) and fluridone (ABA synthesis inhibitor) on water relations and antioxidant enzyme system in 2-year-old seedlings of two apple rootstocks i.e. Malus sieversii (Ledeb.) Roem. (MS) and Malus hupehensis (Pamp.) Rehd. (MH). Drought stress induced ion leakage, accumulation of malondiadehyde (MDA) and decreases in leaf water potential and relative water content (RWC) in both rootstocks, which were significantly alleviated by exogenous ABA application. Drought stress also induced markedly increases in endogenous ABA content and activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), monodehydroascorbate reductase (MDHAR), and glutathione reductase (GR), to a greater magnitude in MS as compared to MH rootstock. Concentration of 100 mol/L and 50 mol/L ABA had the most positive effects on drought-stressed rootstocks of MS and MH, respectively. Spraying optimum exogenous ABA contributed to enhancement in most of the above antioxidant enzymes activities but reduction in content of MDA and maintained the appropriate leaf water potential and RWC in both rootstocks. Pretreatment with fluridone aggravated ion leakage and the accumulation of MDA in two apple rootstocks under drought stress, which was overcome by exogenous ABA application to some extent. In conclusion, the endogenous ABA was probably involved in the regulation of two apple rootstocks in responses to drought stress. (author)

  9. A gate-latch-lock mechanism for hormone signalling by abscisic acid receptors

    KAUST Repository

    Melcher, Karsten

    2009-12-03

    Abscisic acid (ABA) is a ubiquitous hormone that regulates plant growth, development and responses to environmental stresses. Its action is mediated by the PYR/PYL/RCAR family of START proteins, but it remains unclear how these receptors bind ABA and, in turn, how hormone binding leads to inhibition of the downstream type 2C protein phosphatase (PP2C) effectors. Here we report crystal structures of apo and ABA-bound receptors as well as a ternary PYL2-ABA-PP2C complex. The apo receptors contain an open ligand-binding pocket flanked by a gate that closes in response to ABA by way of conformational changes in two highly conserved ?-loops that serve as a gate and latch. Moreover, ABA-induced closure of the gate creates a surface that enables the receptor to dock into and competitively inhibit the PP2C active site. A conserved tryptophan in the PP2C inserts directly between the gate and latch, which functions to further lock the receptor in a closed conformation. Together, our results identify a conserved gate-latch-lock mechanism underlying ABA signalling. © 2009 Macmillan Publishers Limited. All rights reserved.

  10. Abscisic acid in needles of Pinus cembra in relation to ozone exposure.

    Science.gov (United States)

    Bianco; Dalstein

    1999-10-01

    Ozone pollution was analyzed in arolla pine (Pinus cembra L.) forests growing over two mountain ranges located in southern France by using specific ozone-sensitive tobacco plants as bio-indicators and a physico-chemical analyzer. Concentrations of abscisic acid (ABA) were determined in needles of healthy and declining trees in a massif with a declining forest and in a massif with a healthier forest. In addition, ABA was quantified in needles of trees exposed to either charcoal-filtered air or unfiltered air supplemented with ozone in open-top chambers located at the Col du Donon. The concentration of ABA in needles of injured trees increased when the trees were exposed to ozone either under field conditions or in open-top chambers; however, the difference in ABA concentration between control and ozone-exposed needles was less in the open-top chambers, where ozone was the sole variable, than in the field. The results are discussed in the context of the effects of ozone on plant water relations and hormone-mediated cell defense.

  11. Abscisic acid mediates the formation of a suberized stem scar tissue in tomato fruits.

    Science.gov (United States)

    Leide, Jana; Hildebrandt, Ulrich; Hartung, Wolfram; Riederer, Markus; Vogg, Gerd

    2012-04-01

    During harvest, fleshy berry tomato fruits (Solanum lycopersicum) were wounded at their stem scar. Within 3 d, this wound was rapidly sealed by a process covering the wound site with a membranous layer which effectively protects the tomato fruit from excessive water loss, nutrient elution and the entry of pathogens. Chemical analysis of the de novo synthesized stem scar tissue revealed the presence of aromatic and aliphatic components characteristic of the biopolyester suberin. Gene expression patterns associated with suberization were identified at the stem scar region. Changes in the relative abundance of different transcripts suggested a potential involvement of the plant hormone abscisic acid (ABA) in the wound-healing processes. The amount of ABA present in the stem scar tissue showed a significantly increased level during wound healing, whereas ABA-deficient mutants notabilis, flacca and sitiens were largely devoid of this rise in ABA levels. The mutant fruits showed a retarded and less efficient suberization response at the stem scar wound, whereas the rate and strength of this response were positively correlated with ABA content. These results clearly indicate in vivo the involvement of ABA in the suberization-based wound-healing processes at the stem scar tissue of tomato fruits. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

  12. Desiccation tolerance in Physcomitrella patens: Rate of dehydration and the involvement of endogenous abscisic acid (ABA).

    Science.gov (United States)

    Xiao, Lihong; Yobi, Abou; Koster, Karen L; He, Yikun; Oliver, Melvin J

    2018-01-01

    The moss Physcomitrella patens, a model system for basal land plants, tolerates several abiotic stresses, including dehydration. We previously reported that Physcomitrella patens survives equilibrium dehydration to -13 MPa in a closed system at 91% RH. Tolerance of desiccation to water potentials below -100 MPa was only achieved by pretreatment with exogenous abscisic acid (ABA). We report here that gametophores, but not protonemata, can survive desiccation below -100 MPa after a gradual drying regime in an open system, without exogenous ABA. In contrast, faster equilibrium drying at 90% RH for 3-5 days did not induce desiccation tolerance in either tissue. Endogenous ABA accumulated in protonemata and gametophores under both drying regimes, so did not correlate directly with desiccation tolerance. Gametophores of a Ppabi3a/b/c triple knock out transgenic line also survived the gradual dehydration regime, despite impaired ABA signaling. Our results suggest that the initial drying rate, and not the amount of endogenous ABA, may be critical in the acquisition of desiccation tolerance. Results from this work will provide insight into ongoing studies to uncover the role of ABA in the dehydration response and the underlying mechanisms of desiccation tolerance in this bryophyte. © 2017 John Wiley & Sons Ltd.

  13. Autocrine abscisic acid mediates the UV-B-induced inflammatory response in human granulocytes and keratinocytes.

    Science.gov (United States)

    Bruzzone, Santina; Basile, Giovanna; Mannino, Elena; Sturla, Laura; Magnone, Mirko; Grozio, Alessia; Salis, Annalisa; Fresia, Chiara; Vigliarolo, Tiziana; Guida, Lucrezia; De Flora, Antonio; Tossi, Vanesa; Cassia, Raul; Lamattina, Lorenzo; Zocchi, Elena

    2012-06-01

    UV-B is an abiotic environmental stress in both plants and animals. Abscisic acid (ABA) is a phytohormone regulating fundamental physiological functions in plants, including response to abiotic stress. We previously demonstrated that ABA is an endogenous stress hormone also in animal cells. Here, we investigated whether autocrine ABA regulates the response to UV-B of human granulocytes and keratinocytes, the cells involved in UV-triggered skin inflammation. The intracellular ABA concentration increased in UV-B-exposed granulocytes and keratinocytes and ABA was released into the supernatant. The UV-B-induced production of NO and of reactive oxygen species (ROS), phagocytosis, and cell migration were strongly inhibited in granulocytes irradiated in the presence of a monoclonal antibody against ABA. Moreover, presence of the same antibody strongly inhibited release of NO, prostaglandin E2 (PGE(2)), and tumor necrosis factor-α (TNF-α) by UV-B irradiated keratinocytes. Lanthionine synthetase C-like protein 2 (LANCL2) is required for the activation of the ABA signaling pathway in human granulocytes. Silencing of LANCL2 in human keratinocytes by siRNA was accompanied by abrogation of the UV-B-triggered release of PGE(2), TNF-α, and NO and ROS production. These results indicate that UV-B irradiation induces ABA release from human granulocytes and keratinocytes and that autocrine ABA stimulates cell functions involved in skin inflammation. Copyright © 2011 Wiley Periodicals, Inc.

  14. Autocrine abscisic acid plays a key role in quartz-induced macrophage activation.

    Science.gov (United States)

    Magnone, Mirko; Sturla, Laura; Jacchetti, Emanuela; Scarfì, Sonia; Bruzzone, Santina; Usai, Cesare; Guida, Lucrezia; Salis, Annalisa; Damonte, Gianluca; De Flora, Antonio; Zocchi, Elena

    2012-03-01

    Inhalation of quartz induces silicosis, a lung disease where alveolar macrophages release inflammatory mediators, including prostaglandin-E(2) (PGE(2)) and tumor necrosis factor α (TNF-α). Here we report the pivotal role of abscisic acid (ABA), a recently discovered human inflammatory hormone, in silica-induced activation of murine RAW264.7 macrophages and of rat alveolar macrophages (AMs). Stimulation of both RAW264.7 cells and AMs with quartz induced a significant increase of ABA release (5- and 10-fold, respectively), compared to untreated cells. In RAW264.7 cells, autocrine ABA released after quartz stimulation sequentially activates the plasma membrane receptor LANCL2 and NADPH oxidase, generating a Ca(2+) influx resulting in NFκ B nuclear translocation and PGE(2) and TNF-α release (3-, 2-, and 3.5-fold increase, respectively, compared to control, unstimulated cells). Quartz-stimulated RAW264.7 cells silenced for LANCL2 or preincubated with a monoclonal antibody against ABA show an almost complete inhibition of NFκ B nuclear translocation and PGE(2) and TNF-α release compared to controls electroporated with a scramble oligonucleotide or preincubated with an unrelated antibody. AMs showed similar early and late ABA-induced responses as RAW264.7 cells. These findings identify ABA and LANCL2 as key mediators in quartz-induced inflammation, providing possible new targets for antisilicotic therapy.

  15. The interaction of strigolactones with abscisic acid during the drought response in rice

    KAUST Repository

    Haider, Imran

    2018-03-09

    Both strigolactones (SLs) and abscisic acid (ABA) biosynthetically originate from carotenoids. Considering their common origin, the interaction of these two hormones at the biosynthetic and/or regulatory level may be anticipated. Here, we show in rice that drought simultaneously induces SL production in the root, and ABA production and the expression of SL biosynthetic genes in the shoot. Under control conditions, the ABA concentration was higher in shoots of the SL biosynthetic rice mutants dwarf10 (d10) and d17 than in wild-type plants, while a similar trend was observed for SL-perception mutant d3. These differences were enhanced under drought. However, drought did not result in an increase in leaf ABA content in rice mutant line d27, carrying a mutation in the gene encoding the first committed enzyme in SL biosynthesis, to the same extent as in the other SL mutants and the wild-type. Accordingly, d10, d17 and d3 lines were more drought tolerant than wild-type plants, whereas d27 displayed decreased tolerance. Finally, over-expression of OsD27 in rice resulted in increased levels of ABA when compared with wild-type plants. We conclude that the SL and ABA pathways are connected with each other through D27, which is playing a crucial role in determining ABA and SL content in rice.

  16. What are the evolutionary origins of stomatal responses to abscisic acid in land plants?

    Science.gov (United States)

    Sussmilch, Frances C; Brodribb, Timothy J; McAdam, Scott A M

    2017-04-01

    The evolution of active stomatal closure in response to leaf water deficit, mediated by the hormone abscisic acid (ABA), has been the subject of recent debate. Two different models for the timing of the evolution of this response recur in the literature. A single-step model for stomatal control suggests that stomata evolved active, ABA-mediated control of stomatal aperture, when these structures first appeared, prior to the divergence of bryophyte and vascular plant lineages. In contrast, a gradualistic model for stomatal control proposes that the most basal vascular plant stomata responded passively to changes in leaf water status. This model suggests that active ABA-driven mechanisms for stomatal responses to water status instead evolved after the divergence of seed plants, culminating in the complex, ABA-mediated responses observed in modern angiosperms. Here we review the findings that form the basis for these two models, including recent work that provides critical molecular insights into resolving this intriguing debate, and find strong evidence to support a gradualistic model for stomatal evolution. © 2017 Institute of Botany, Chinese Academy of Sciences.

  17. A gate-latch-lock mechanism for hormone signalling by abscisic acid receptors

    Energy Technology Data Exchange (ETDEWEB)

    Melcher, Karsten; Ng, Ley-Moy; Zhou, X Edward; Soon, Fen-Fen; Xu, Yong; Suino-Powell, Kelly M; Park, Sang-Youl; Weiner, Joshua J; Fujii, Hiroaki; Chinnusamy, Viswanathan; Kovach, Amanda; Li, Jun; Wang, Yonghong; Li, Jiayang; Peterson, Francis C; Jensen, Davin R; Yong, Eu-Leong; Volkman, Brian F; Cutler, Sean R; Zhu, Jian-Kang; Xu, H Eric; (NU Sinapore); (Van Andel); (MCW); (UCR); (Chinese Aca. Sci.)

    2010-01-12

    Abscisic acid (ABA) is a ubiquitous hormone that regulates plant growth, development and responses to environmental stresses. Its action is mediated by the PYR/PYL/RCAR family of START proteins, but it remains unclear how these receptors bind ABA and, in turn, how hormone binding leads to inhibition of the downstream type 2C protein phosphatase (PP2C) effectors. Here we report crystal structures of apo and ABA-bound receptors as well as a ternary PYL2-ABA-PP2C complex. The apo receptors contain an open ligand-binding pocket flanked by a gate that closes in response to ABA by way of conformational changes in two highly conserved β-loops that serve as a gate and latch. Moreover, ABA-induced closure of the gate creates a surface that enables the receptor to dock into and competitively inhibit the PP2C active site. A conserved tryptophan in the PP2C inserts directly between the gate and latch, which functions to further lock the receptor in a closed conformation. Together, our results identify a conserved gate-latch-lock mechanism underlying ABA signalling.

  18. The Arabidopsis Vacuolar Sorting Receptor1 Is Required for Osmotic Stress-Induced Abscisic Acid Biosynthesis

    KAUST Repository

    Wang, Zhen-Yu

    2014-11-21

    Osmotic stress activates the biosynthesis of the phytohormone abscisic acid (ABA) through a pathway that is rate limited by the carotenoid cleavage enzyme 9-cis-epoxycarotenoid dioxygenase (NCED). To understand the signal transduction mechanism underlying the activation of ABA biosynthesis, we performed a forward genetic screen to isolate mutants defective in osmotic stress regulation of the NCED3 gene. Here, we identified the Arabidopsis (Arabidopsis thaliana) Vacuolar Sorting Receptor1 (VSR1) as a unique regulator of ABA biosynthesis. The vsr1 mutant not only shows increased sensitivity to osmotic stress, but also is defective in the feedback regulation of ABA biosynthesis by ABA. Further analysis revealed that vacuolar trafficking mediated by VSR1 is required for osmotic stress-responsive ABA biosynthesis and osmotic stress tolerance. Moreover, under osmotic stress conditions, the membrane potential, calcium flux, and vacuolar pH changes in the vsr1 mutant differ from those in the wild type. Given that manipulation of the intracellular pH is sufficient to modulate the expression of ABA biosynthesis genes, including NCED3, and ABA accumulation, we propose that intracellular pH changes caused by osmotic stress may play a signaling role in regulating ABA biosynthesis and that this regulation is dependent on functional VSR1.

  19. The pivotal role of abscisic acid signaling during transition from seed maturation to germination.

    Science.gov (United States)

    Yan, An; Chen, Zhong

    2017-05-01

    Seed maturation and germination are two continuous developmental processes that link two distinct generations in spermatophytes; the precise genetic control of these two processes is, therefore, crucially important for the survival of the next generation. Pieces of experimental evidence accumulated so far indicate that a concerted action of endogenous signals and environmental cues is required to govern these processes. Plant hormone abscisic acid (ABA) has been suggested to play a predominant role in directing seed maturation and maintaining seed dormancy under unfavorable environmental conditions until antagonized by gibberellins (GA) and certain environmental cues to allow the commencement of seed germination when environmental conditions are favorable; therefore, the balance of ABA and GA is a major determinant of the timing of seed germination. Due to the advent of new technologies and system biology approaches, molecular studies are beginning to draw a picture of the sophisticated genetic network that drives seed maturation during the past decade, though the picture is still incomplete and many details are missing. In this review, we summarize recent advances in ABA signaling pathway in the regulation of seed maturation as well as the transition from seed maturation to germination, and highlight the importance of system biology approaches in the study of seed maturation.

  20. Protein degradation mechanisms modulate abscisic acid signaling and responses during abiotic stress.

    Science.gov (United States)

    Jurkiewicz, Pawel; Batoko, Henri

    2018-02-01

    Abiotic stresses such as salinity, drought, high temperature or freezing can be perceived, in part, as a transient or permanent hyperosmotic stress by the plant cell. As sessile organisms, the detrimental effects of these environmental insults limit plants productivity but also their geographical distribution. Sensing and signaling events that detect the hyperosmotic (or simply osmotic) stress involve the cellular increase of active abscisic acid (ABA). The stress phytohormone ABA regulates fundamental growth and developmental processes in the plant by marshalling metabolic and gene-expression reprogramming. Among the ABA-responsive genes, some are strictly ABA-dependent in that their expression is almost undetectable in absence of elevated levels of cellular ABA, thus their physiological role may be required only transiently. In addition, ABA-dependent modulation of some of the signaling effectors can be irreversible. In this review, without any pretention to being exhaustive, we use specific examples to illustrate how mechanistically conserved eukaryotic cell proteolytic pathways affect ABA-dependent signaling. We describe how defined proteolysis mechanisms in the plant cell, including Regulated Intramembrane Proteolysis (RIP), the Ubiquitin 26S Proteasomal System (UPS), the endocytic and autophagy pathways, contribute to regulate the spatiotemporal level and activity of PP2Cs (protein phosphatases 2C), and how an intriguing ABA-induced protein, the plant Translocator protein (TSPO), is targeted for degradation. Degradation of regulatory or effector molecules modulates or desensitizes ABA-dependent signaling and reestablishes cellular homeostasis. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Abscisic acid stimulates a calcium-dependent protein kinase in grape berry.

    Science.gov (United States)

    Yu, Xiang-Chun; Li, Mei-Jun; Gao, Gui-Feng; Feng, Hai-Zhong; Geng, Xue-Qing; Peng, Chang-Cao; Zhu, Sai-Yong; Wang, Xiao-Jing; Shen, Yuan-Yue; Zhang, Da-Peng

    2006-02-01

    It has been demonstrated that calcium plays a central role in mediating abscisic acid (ABA) signaling, but many of the Ca2+-binding sensory proteins as the components of the ABA-signaling pathway remain to be elucidated. Here we identified, characterized, and purified a 58-kD ABA-stimulated calcium-dependent protein kinase from the mesocarp of grape berries (Vitis vinifera x Vitis labrusca), designated ACPK1 (for ABA-stimulated calcium-dependent protein kinase1). ABA stimulates ACPK1 in a dose-dependent manner, and the ACPK1 expression and enzyme activities alter accordantly with the endogenous ABA concentrations during fruit development. The ABA-induced ACPK1 stimulation appears to be transient with a rapid effect in 15 min but also with a slow and steady state of induction after 60 min. ABA acts on ACPK1 indirectly and dependently on in vivo state of the tissues. Two inactive ABA isomers, (-)-2-cis, 4-trans-ABA and 2-trans, 4-trans-(+/-)-ABA, are ineffective for inducing ACPK1 stimulation, revealing that the ABA-induced effect is stereo specific to physiological active (+)-2-cis, 4-trans-ABA. The other phytohormones such as auxin indoleacetic acid, gibberellic acid, synthetic cytokinin N-benzyl-6-aminopurine, and brassinolide are also ineffective in this ACPK1 stimulation. Based on sequencing of the two-dimensional electrophoresis-purified ACPK1, we cloned the ACPK1 gene. The ACPK1 is expressed specifically in grape berry covering a fleshy portion and seeds, and in a developmental stage-dependent manner. We further showed that ACPK1 is localized in both plasma membranes and chloroplasts/plastids and positively regulates plasma membrane H+-ATPase in vitro, suggesting that ACPK1 may be involved in the ABA-signaling pathway.

  2. Chloroplast protein PLGG1 is involved in abscisic acid-regulated lateral root development and stomatal movement in Arabidopsis.

    Science.gov (United States)

    Dong, Huan; Bai, Ling; Chang, Jie; Song, Chun-Peng

    2018-01-01

    The plant hormone abscisic acid (ABA) plays a crucial role in root architecture; however, the molecular mechanism of ABA-regulated lateral root (LR) growth is not well known. We screened an Arabidopsis thaliana mutant with LR growth that was sensitive to ABA from a T-DNA insertion mutant library, which was an allelic mutant of plgg1-1, termed plgg1-2. PLGG1 encodes a chloroplast protein that transports plastidic glycolate and glycerate. The length and number of LRs at the root-hypocotyl junction of plgg1-1 and plgg1-2 were significantly impaired under exogenous ABA treatment, and the transgenic plant complementary lines of plgg1-2 restored LR growth in response to ABA. In addition, we found that PLGG1 is involved in other major ABA responses, including ABA-inhibited seed germination, ABA-mediated stomatal movement, and drought tolerance. These findings open new perspectives on elucidating the mechanism of ABA response, and provide clues for analysing the functions of chloroplast proteins in regulating root growth. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Implication of abscisic acid on ripening and quality in sweet cherries: differential effects during pre- and postharvest

    Directory of Open Access Journals (Sweden)

    Verónica eTijero

    2016-05-01

    Full Text Available Sweet cherry, a non-climacteric fruit, is usually cold-stored during postharvest to prevent over-ripening. The aim of the study was to evaluate the role of abscisic acid (ABA on fruit growth and ripening of this fruit, considering as well its putative implication in over-ripening and effects on quality. We measured the endogenous concentrations of ABA during the ripening of sweet cherries (Prunus avium L. var. Prime Giant collected from orchard trees and in cherries exposed to 4ºC and 23ºC during 10d of postharvest. Furthermore, we examined to what extent endogenous ABA concentrations were related to quality parameters, such as fruit biomass, anthocyanin accumulation and levels of vitamins C and E. Endogenous concentrations of ABA in fruits increased progressively during fruit growth and ripening on the tree, to decrease later during postharvest at 23ºC. Cold treatment, however, increased ABA levels and led to an inhibition of over-ripening. Furthermore, ABA levels positively correlated with anthocyanin and vitamin E levels during preharvest, but not during postharvest. We conclude that ABA plays a major role in sweet cherry development, stimulating its ripening process and positively influencing quality parameters during preharvest. The possible influence of ABA preventing over-ripening in cold-stored sweet cherries is also discussed.

  4. Implication of Abscisic Acid on Ripening and Quality in Sweet Cherries: Differential Effects during Pre- and Post-harvest

    Science.gov (United States)

    Tijero, Verónica; Teribia, Natalia; Muñoz, Paula; Munné-Bosch, Sergi

    2016-01-01

    Sweet cherry, a non-climacteric fruit, is usually cold-stored during post-harvest to prevent over-ripening. The aim of the study was to evaluate the role of abscisic acid (ABA) on fruit growth and ripening of this fruit, considering as well its putative implication in over-ripening and effects on quality. We measured the endogenous concentrations of ABA during the ripening of sweet cherries (Prunus avium L. var. Prime Giant) collected from orchard trees and in cherries exposed to 4°C and 23°C during 10 days of post-harvest. Furthermore, we examined to what extent endogenous ABA concentrations were related to quality parameters, such as fruit biomass, anthocyanin accumulation and levels of vitamins C and E. Endogenous concentrations of ABA in fruits increased progressively during fruit growth and ripening on the tree, to decrease later during post-harvest at 23°C. Cold treatment, however, increased ABA levels and led to an inhibition of over-ripening. Furthermore, ABA levels positively correlated with anthocyanin and vitamin E levels during pre-harvest, but not during post-harvest. We conclude that ABA plays a major role in sweet cherry development, stimulating its ripening process and positively influencing quality parameters during pre-harvest. The possible influence of ABA preventing over-ripening in cold-stored sweet cherries is also discussed. PMID:27200070

  5. Abscisic acid alleviates iron deficiency by promoting root iron reutilization and transport from root to shoot in Arabidopsis.

    Science.gov (United States)

    Lei, Gui Jie; Zhu, Xiao Fang; Wang, Zhi Wei; Dong, Fang; Dong, Ning Yu; Zheng, Shao Jian

    2014-04-01

    Abscisic acid (ABA) has been demonstrated to be involved in iron (Fe) homeostasis, but the underlying mechanism is largely unknown. Here, we found that Fe deficiency induced ABA accumulation rapidly (within 6 h) in the roots of Arabidopsis. Exogenous ABA at 0.5 μM decreased the amount of root apoplastic Fe bound to pectin and hemicellulose, and increased the shoot Fe content significantly, thus alleviating Fe deficiency-induced chlorosis. Exogenous ABA promoted the secretion of phenolics to release apoplastic Fe and up-regulated the expression of AtNRAMP3 to enhance reutilization of Fe stored in the vacuoles, leading to a higher level of soluble Fe and lower ferric-chelate reductase (FCR) activity in roots. Treatment with ABA also led to increased Fe concentrations in the xylem sap, partially because of the up-regulation of AtFRD3, AtYSL2 and AtNAS1, genes related to long-distance transport of Fe. Exogenous ABA could not alleviate the chlorosis of abi5 mutant resulting from the significantly low expression of AtYSL2 and low transport of Fe from root to shoot. Taken together, our data support the conclusion that ABA is involved in the reutilization and transport of Fe from root to shoot under Fe deficiency conditions in Arabidopsis. © 2013 John Wiley & Sons Ltd.

  6. Abscisic acid and ethylene in mutants of Arabidopsis thaliana differing in their resistance to ultraviolet (UV-B) radiation stress

    International Nuclear Information System (INIS)

    Rakitina, T.Ya.; Vlasov, P.V.; Jalilova, F.Kh.; Kefeli, V.I.

    1994-01-01

    The effects of ultraviolet irradiation (between 280 and 320 nm) on plant survival, ethylene evolution, and abscisic acid (ABA) content were studied in Arabidopsis thaliana (L.) Heunh. plants. Three genetic lines of Arabidopsis differing in their resistance to ultraviolet (UV-B) radiation stress were used. UV-B irradiation had detrimental effects on plant survival, enhanced ethylene evolution, and increased ABA content in the plants of all three lines. The higher ultraviolet dose was absorbed, the less was the number of surviving plants and the higher were the levels of both phytohormones. The maximum ethylene evolution occurred during the initial two to four hours after irradiation, but the ABA content peaked only after 24 h. The most resistant line showed the highest ABA content and the fastest ethylene evolution, whereas, in the susceptible line, both indices were the lowest. After UV-B treatment, the ABA-deficient Arabidopsis mutant evolved four to six times more ethylene than the plants with normal ABA content. Stress ethylene production evidently did not depend on the level of endogenous ABA as the kinetics of ethylene evolution was similar in the ABA-deficient mutant and in other studied Arabidopsis lines

  7. Abscisic acid as an internal integrator of multiple physiological processes modulates leaf senescence onset in Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Yuwei eSong

    2016-02-01

    Full Text Available Many studies have shown that exogenous abscisic acid (ABA promotes leaf abscission and senescence. However, owing to a lack of genetic evidence, ABA function in plant senescence has not been clearly defined. Here, two-leaf early-senescence mutants (eas that were screened by chlorophyll fluorescence imaging and named eas1-1 and eas1-2 showed high photosynthetic capacity in the early stage of plant growth compared with the wild type. Gene mapping showed that eas1-1 and eas1-2 are two novel ABA2 allelic mutants. Under unstressed conditions, the eas1 mutations caused plant dwarf, early germination, larger stomatal apertures, and early leaf senescence compared with those of the wild type. Flow cytometry assays showed that the cell apoptosis rate in eas1 mutant leaves was higher than that of the wild type after day 30. A significant increase in the transcript levels of several senescence-associated genes, especially SAG12, was observed in eas1 mutant plants in the early stage of plant growth. More importantly, ABA-activated calcium channel activity in plasma membrane and induced the increase of cytoplasmic calcium concentration in guard cells are suppressed due to the mutation of EAS1. In contrast, the eas1 mutants lost chlorophyll and ion leakage significant faster than in the wild type under treatment with calcium channel blocker. Hence, our results indicate that endogenous ABA level is an important factor controlling the onset of leaf senescence through Ca2+ signaling.

  8. The role of the atypical kinases ABC1K7 and ABC1K8 in abscisic acid responses

    Directory of Open Access Journals (Sweden)

    Anna eManara

    2016-03-01

    Full Text Available The ABC1K family of atypical kinases (activity of bc1 complex kinase is represented in bacteria, archaea and eukaryotes. In plants they regulate diverse physiological processes in the chloroplasts and mitochondria, but their precise functions are poorly defined. ABC1K7 and ABC1K8 are probably involved in oxidative stress responses, isoprenyl lipid synthesis and distribution of iron within chloroplasts. Because reactive oxygen species take part in abscisic acid (ABA-mediated processes, we investigated the functions of ABC1K7 and ABC1K8 during germination, stomatal movement and leaf senescence. Both genes were upregulated by ABA treatment and some ABA-responsive physiological processes were affected in abc1k7 and abc1k8 mutants. Germination was more severely affected by ABA, osmotic stress and salt stress in the single and double mutants; the stomatal aperture was smaller in the mutants under standard growth conditions and was not further reduced by exogenous ABA application; ABA-induced senescence symptoms were more severe in the leaves of the single and double mutants compared to wild type leaves. Taken together, our results suggest that ABC1K7 and ABC1K8 might be involved in the cross-talk between ABA and ROS signaling.

  9. Microarray analysis of transcriptional responses to abscisic acid and osmotic, salt, and drought stress in the moss, Physcomitrella patens.

    Science.gov (United States)

    Cuming, Andrew C; Cho, Sung Hyun; Kamisugi, Yasuko; Graham, Helen; Quatrano, Ralph S

    2007-01-01

    Dehydration tolerance was an adaptive trait necessary for the colonization of land by plants, and remains widespread among bryophytes: the nearest extant relatives of the first land plants. A genome-wide analysis was undertaken of water-stress responses in the model moss Physcomitrella patens to identify stress-responsive genes. An oligonucleotide microarray was used for transcriptomic analysis of Physcomitrella treated with abscisic acid (ABA), or subjected to osmotic, salt and drought stress. Bioinformatic analysis of the Physcomitrella genome identified the responsive genes, and a number of putative stress-related cis-regulatory elements. In protonemal tissue, 130 genes were induced by dehydration, 56 genes by ABA, but only 10 and eight genes, respectively, by osmotic and salt stress. Fifty-one genes were induced by more than one treatment. Seventy-six genes, principally encoding chloroplast proteins, were drought down-regulated. Many ABA- and drought-responsive genes are homologues of angiosperm genes expressed during drought stress and seed development. These ABA- and drought-responsive genes include those encoding a number of late embryogenesis abundant (LEA) proteins, a 'DREB' transcription factor and a Snf-related kinase homologous with the Arabidopsis ABA signal transduction component 'OPEN STOMATA 1'. Evolutionary capture of conserved stress-regulatory transcription factors by the seed developmental pathway probably accounts for the seed-specificity of desiccation tolerance among angiosperms.

  10. A Unique Short-Chain Dehydrogenase/Reductase in Arabidopsis Glucose Signaling and Abscisic Acid Biosynthesis and Functions

    Science.gov (United States)

    Cheng, Wan-Hsing; Endo, Akira; Zhou, Li; Penney, Jessica; Chen, Huei-Chi; Arroyo, Analilia; Leon, Patricia; Nambara, Eiji; Asami, Tadao; Seo, Mitsunori; Koshiba, Tomokazu; Sheen, Jen

    2002-01-01

    Glc has hormone-like functions and controls many vital processes through mostly unknown mechanisms in plants. We report here on the molecular cloning of GLUCOSE INSENSITIVE1 (GIN1) and ABSCISIC ACID DEFICIENT2 (ABA2) which encodes a unique Arabidopsis short-chain dehydrogenase/reductase (SDR1) that functions as a molecular link between nutrient signaling and plant hormone biosynthesis. SDR1 is related to SDR superfamily members involved in retinoid and steroid hormone biosynthesis in mammals and sex determination in maize. Glc antagonizes ethylene signaling by activating ABA2/GIN1 and other abscisic acid (ABA) biosynthesis and signaling genes, which requires Glc and ABA synergistically. Analyses of aba2/gin1 null mutants define dual functions of endogenous ABA in inhibiting the postgermination developmental switch modulated by distinct Glc and osmotic signals and in promoting organ and body size and fertility in the absence of severe stress. SDR1 is sufficient for the multistep conversion of plastid- and carotenoid-derived xanthoxin to abscisic aldehyde in the cytosol. The surprisingly restricted spatial and temporal expression of SDR1 suggests the dynamic mobilization of ABA precursors and/or ABA. PMID:12417697

  11. Visualisation of abscisic acid and 12-oxo-phytodienoic acid in immature Phaseolus vulgaris L. seeds using desorption electrospray ionisation-imaging mass spectrometry

    OpenAIRE

    Enomoto, Hirofumi; Sensu, Takuya; Sato, Kei; Sato, Futoshi; Paxton, Thanai; Yumoto, Emi; Miyamoto, Koji; Asahina, Masashi; Yokota, Takao; Yamane, Hisakazu

    2017-01-01

    The plant hormone abscisic acid (ABA) and the jasmonic acid related-compound 12-oxo-phytodienoic acid (OPDA) play crucial roles in seed development, dormancy, and germination. However, a lack of suitable techniques for visualising plant hormones has restricted the investigation of their biological mechanisms. In the present study, desorption electrospray ionisation-imaging mass spectrometry (DESI-IMS), a powerful tool for visualising metabolites in biological tissues, was used to visualise AB...

  12. Effects of abscisic acid and xanthoxin on elongation and gravitropism in primary roots of Zea mays

    Science.gov (United States)

    Lee, J. S.; Hasenstein, K. H.; Mulkey, T. J.; Yang, R. L.; Evans, M. L.

    1990-01-01

    We examined the involvement of abscisic acid (ABA) and xanthoxin (Xan) in maize root gravitropism by (1) testing the ability of ABA to allow positive gravitropism in dark-grown seedlings of the maize cultivar LG11, a cultivar known to require light for positive gravitropism of the primary root, (2) comparing curvature in roots in which half of the cap had been excised and replaced with agar containing either ABA or indole-3-acetic acid (IAA), (3) measuring gravitropism in roots of seedlings submerged in oxygenated solutions of ABA or IAA and (4) testing the effect of Xan on root elongation. Using a variety of methods of applying ABA to the root, we found that ABA did not cause horizontally-oriented primary roots of dark-grown seedlings to become positively gravitropic. Replacing half of the root cap of vertically oriented roots with an agar block containing ABA had little or no effect on curvature relative to that of controls in which the half cap was replaced by a plain agar block. Replacement of the removed half cap with IAA either canceled or reversed the curvature displayed by controls. When light-grown seedlings were submerged in ABA they responded strongly to gravistimulation while those in IAA did not. Xan (up to 0.1 mM) did not affect root elongation. The results indicate that ABA is not a likely mediator of root gravitropism and that the putative ABA precursor, Xan, lacks the appropriate growth-inhibiting properties to serve as a mediator of root gravitropism.

  13. Plastid located WHIRLY1 enhances responsiveness of Arabidopsis seedlings towards abscisic acid

    Directory of Open Access Journals (Sweden)

    Rena eIsemer

    2012-12-01

    Full Text Available WHIRLY1 is a protein that can be translocated from the plastids to the nucleus, making it an ideal candidate for communicating information between these two compartments. Mutants of Arabidopsis thaliana lacking WHIRLY1 (why1 were shown to have a reduced sensitivity towards salicylic acid (SA and abscisic acid (ABA during germination. Germination assays in the presence of abamine, an inhibitor of ABA biosynthesis, revealed that the effect of SA on germination was in fact caused by a concomitant stimulation of ABA biosynthesis. In order to distinguish whether the plastid or the nuclear isoform of WHIRLY1 is adjusting the responsiveness towards ABA, sequences encoding either the complete WHIRLY1 protein or a truncated form lacking the plastid targeting peptide were overexpressed in the why1 mutant background. In plants overex¬pressing the full-length sequence, WHIRLY1 accumulated in both plastids and the nucleus, whereas in plants overexpressing the truncated sequence, WHIRLY1 accumulated exclusively in the nucleus. Seedlings containing recombinant WHIRLY1 in both compartments were hypersen¬sitive towards ABA. In contrast, seedlings possessing only the nuclear form of WHIRLY1 were as insensitive towards ABA as the why1 mutants. ABA was furthermore shown to lower the rate of germination of wildtype seeds even in the presence of abamine which is known to inhibit the formation of xanthoxin, the plastid located precursor of ABA. From this we conclude that plastid located WHIRLY1 enhances the responsiveness of seeds towards ABA even when ABA is supplied exogenously.

  14. Abscisic acid enhances glucose disposal and induces brown fat activity in adipocytes in vitro and in vivo.

    Science.gov (United States)

    Sturla, Laura; Mannino, Elena; Scarfì, Sonia; Bruzzone, Santina; Magnone, Mirko; Sociali, Giovanna; Booz, Valeria; Guida, Lucrezia; Vigliarolo, Tiziana; Fresia, Chiara; Emionite, Laura; Buschiazzo, Ambra; Marini, Cecilia; Sambuceti, Gianmario; De Flora, Antonio; Zocchi, Elena

    2017-02-01

    Abscisic acid (ABA) is a plant hormone also present in animals, where it is involved in the regulation of innate immune cell function and of glucose disposal, through its receptor LANCL2. ABA stimulates glucose uptake by myocytes and pre-adipocytes in vitro and oral ABA improves glycemic control in rats and in healthy subjects. Here we investigated the role of the ABA/LANCL2 system in the regulation of glucose uptake and metabolism in adipocytes. Silencing of LANCL2 abrogated both the ABA- and insulin-induced increase of glucose transporter-4 expression and of glucose uptake in differentiated 3T3-L1 murine adipocytes; conversely, overexpression of LANCL2 enhanced basal, ABA- and insulin-stimulated glucose uptake. As compared with insulin, ABA treatment of adipocytes induced lower triglyceride accumulation, CO 2 production and glucose-derived fatty acid synthesis. ABA per se did not induce pre-adipocyte differentiation in vitro, but stimulated adipocyte remodeling in terminally differentiated cells, with a reduction in cell size, increased mitochondrial content, enhanced O 2 consumption, increased transcription of adiponectin and of brown adipose tissue (BAT) genes. A single dose of oral ABA (1μg/kg body weight) increased BAT glucose uptake 2-fold in treated rats compared with untreated controls. One-month-long ABA treatment at the same daily dose significantly upregulated expression of BAT markers in the WAT and in WAT-derived preadipocytes from treated mice compared with untreated controls. These results indicate a hitherto unknown role of LANCL2 in adipocyte sensitivity to insulin-stimulated glucose uptake and suggest a role for ABA in the induction and maintenance of BAT activity. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Cuticle Biosynthesis in Tomato Leaves Is Developmentally Regulated by Abscisic Acid.

    Science.gov (United States)

    Martin, Laetitia B B; Romero, Paco; Fich, Eric A; Domozych, David S; Rose, Jocelyn K C

    2017-07-01

    The expansion of aerial organs in plants is coupled with the synthesis and deposition of a hydrophobic cuticle, composed of cutin and waxes, which is critically important in limiting water loss. While the abiotic stress-related hormone abscisic acid (ABA) is known to up-regulate wax accumulation in response to drought, the hormonal regulation of cuticle biosynthesis during organ ontogeny is poorly understood. To address the hypothesis that ABA also mediates cuticle formation during organ development, we assessed the effect of ABA deficiency on cuticle formation in three ABA biosynthesis-impaired tomato mutants. The mutant leaf cuticles were thinner, had structural abnormalities, and had a substantial reduction in levels of cutin. ABA deficiency also consistently resulted in differences in the composition of leaf cutin and cuticular waxes. Exogenous application of ABA partially rescued these phenotypes, confirming that they were a consequence of reduced ABA levels. The ABA mutants also showed reduced expression of genes involved in cutin or wax formation. This difference was again countered by exogenous ABA, further indicating regulation of cuticle biosynthesis by ABA. The fruit cuticles were affected differently by the ABA-associated mutations, but in general were thicker. However, no structural abnormalities were observed, and the cutin and wax compositions were less affected than in leaf cuticles, suggesting that ABA action influences cuticle formation in an organ-dependent manner. These results suggest dual roles for ABA in regulating leaf cuticle formation: one that is fundamentally associated with leaf expansion, independent of abiotic stress, and another that is drought induced. © 2017 American Society of Plant Biologists. All Rights Reserved.

  16. Assessing the Effect of Organoclays and Biochar on the Fate of Abscisic Acid in Soil.

    Science.gov (United States)

    Gámiz, Beatriz; Cox, Lucía; Hermosín, M Carmen; Spokas, Kurt; Celis, Rafael

    2017-01-11

    The potential use of allelopathic and signaling compounds as environmentally friendly agrochemicals is a subject of increasing interest, but the fate of these compounds once they reach the soil environment is poorly understood. This work studied how the sorption, persistence, and leaching of the two enantiomers of the phytohormone abscisic acid (ABA) in agricultural soil was affected by the amendments of two organoclays (SA-HDTMA and Cloi10) and a biochar derived from apple wood (BC). In conventional 24-h batch sorption experiments, higher affinity toward ABA enantiomers was displayed by SA-HDTMA followed by Cloi10 and then BC. Desorption could be ascertained only in BC, where ABA enantiomers presented difficulties to be desorbed. Dissipation of ABA in the soil was enantioselective with S-ABA being degraded more quickly than R-ABA, and followed the order unamended > Cloi10-amended > BC-amended > SA-HDTMA-amended soil for both enantiomers. Sorption determined during the incubation experiment indicated some loss of sorption capacity with time in organoclay-amended soil and increasing sorption in BC-amended soil, suggesting surface sorption mechanisms for organoclays and slow (potentially pore filling) kinetics in BC-amended soil. The leaching of ABA enantiomers was delayed after amendment of soil to an extent that depended on the amendment sorption capacity, and it was almost completely suppressed by addition of BC due to its irreversible sorption. Organoclays and BC affected differently the final behavior and enantioselectivity of ABA in soil as a consequence of dissimilar sorption capacities and alterations in sorption with time, which will affect the plant and microbial availability of endogenous and exogenous ABA in the rhizosphere.

  17. Patterns of auxin and abscisic acid movement in the tips of gravistimulated primary roots of maize

    Science.gov (United States)

    Young, L. M.; Evans, M. L.

    1996-01-01

    Because both abscisic acid (ABA) and auxin (IAA) have been suggested as possible chemical mediators of differential growth during root gravitropism, we compared with redistribution of label from applied 3H-IAA and 3H-ABA during maize root gravitropism and examined the relative basipetal movement of 3H-IAA and 3H-ABA applied to the caps of vertical roots. Lateral movement of 3H-ABA across the tips of vertical roots was non-polar and about 2-fold greater than lateral movement of 3H-IAA (also non-polar). The greater movement of ABA was not due to enhanced uptake since the uptake of 3H-IAA was greater than that of 3H-ABA. Basipetal movement of label from 3H-IAA or 3H-ABA applied to the root cap was determined by measuring radioactivity in successive 1 mm sections behind the tip 90 minutes after application. ABA remained largely in the first mm (point of application) whereas IAA was concentrated in the region 2-4 mm from the tip with substantial levels found 7-8 mm from the tip. Pretreatment with inhibitors of polar auxin transport decreased both gravicurvature and the basipetal movement of IAA. When roots were placed horizontally, the movement of 3H-IAA from top to bottom across the cap was enhanced relative to movement from bottom to top whereas the pattern of movement of label from 3H-ABA was unaffected. These results are consistent with the hypothesis that IAA plays a role in root gravitropism but contrary to the idea that gravi-induced asymmetric distribution of ABA contributes to the response.

  18. Identification of Interactions between Abscisic Acid and Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase.

    Directory of Open Access Journals (Sweden)

    Marek M Galka

    Full Text Available Abscisic acid ((+-ABA is a phytohormone involved in the modulation of developmental processes and stress responses in plants. A chemical proteomics approach using an ABA mimetic probe was combined with in vitro assays, isothermal titration calorimetry (ITC, x-ray crystallography and in silico modelling to identify putative (+-ABA binding-proteins in crude extracts of Arabidopsis thaliana. Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco was identified as a putative ABA-binding protein. Radiolabelled-binding assays yielded a Kd of 47 nM for (+-ABA binding to spinach Rubisco, which was validated by ITC, and found to be similar to reported and experimentally derived values for the native ribulose-1,5-bisphosphate (RuBP substrate. Functionally, (+-ABA caused only weak inhibition of Rubisco catalytic activity (Ki of 2.1 mM, but more potent inhibition of Rubisco activation (Ki of ~ 130 μM. Comparative structural analysis of Rubisco in the presence of (+-ABA with RuBP in the active site revealed only a putative low occupancy (+-ABA binding site on the surface of the large subunit at a location distal from the active site. However, subtle distortions in electron density in the binding pocket and in silico docking support the possibility of a higher affinity (+-ABA binding site in the RuBP binding pocket. Overall we conclude that (+-ABA interacts with Rubisco. While the low occupancy (+-ABA binding site and weak non-competitive inhibition of catalysis may not be relevant, the high affinity site may allow ABA to act as a negative effector of Rubisco activation.

  19. Abscisic acid metabolism and anthocyanin synthesis in grape skin are affected by light emitting diode (LED) irradiation at night.

    Science.gov (United States)

    Kondo, Satoru; Tomiyama, Hiroyuki; Rodyoung, Abhichartbut; Okawa, Katsuya; Ohara, Hitoshi; Sugaya, Sumiko; Terahara, Norihiko; Hirai, Nobuhiro

    2014-06-15

    The effects of blue and red light irradiation at night on abscisic acid (ABA) metabolism and anthocyanin synthesis were examined in grape berries. The expressions of VlMYBA1-2, VlMYBA2, UDP-glucose-flavonoid 3-O-glucosyltransferase (VvUFGT), 9-cis-epoxycarotenoid dioxygenase (VvNCED1), and ABA 8'-hydroxylase (VvCYP707A1) were also investigated. Endogenous ABA, its metabolite phaseic acid (PA), and the expressions of VvNCED1 and VvCYP707A1 were highest in red light-emitting diode (LED)-treated skin. In contrast, anthocyanin concentrations were highest in blue LED-treated skin, followed by red LED treatment. However, the expressions of VlMYBA1-2, VlMYBA2, and VvUFGT did not necessarily coincide with anthocyanin concentrations. The quality of coloring may depend on the amount of malvidin-based anthocyanin, which increased toward harvest in blue and red LED-treated skin, unlike in untreated controls. An increase in sugars was also observed in blue and red LED-treated skin. These results suggest that blue LED irradiation at night may be effective in increasing anthocyanin and sugar concentrations in grape berries. However, there is evidence that another factor may influence anthocyanin concentrations in grape berry skin significantly more than endogenous ABA: ABA concentrations were highest in red LED-treated skin, which had lower anthocyanin concentrations than blue LED-treated skin. Copyright © 2014 Elsevier GmbH. All rights reserved.

  20. Effects of abscisic acid and high osmoticum on storage protein gene expression in microspore embryos of Brassica napus

    International Nuclear Information System (INIS)

    Wilen, R.W.; Mandel, R.M.; Pharis, R.P.; Moloney, M.M.; Holbrook, L.A.

    1990-01-01

    Storage protein gene expression, characteristic of mid- to late embryogenesis, was investigated in microspore embryos of rapeseed (Brassica napus). These embryos, derived from the immature male gametophyte, accumulate little or no detectable napin or cruciferin mRNA when cultured on hormone-free medium containing 13% sucrose. The addition of abscisic acid (ABA) to the medium results in an increase in detectable transcripts encoding both these polypeptides. Storage protein mRNA is induced at 1 micromolar ABA with maximum stimulation occurring between 5 and 50 micromolar. This hormone induction results in a level of storage protein mRNA that is comparable to that observed in zygotic embryos of an equivalent morphological stage. Effects similar to that of ABA are noted when 12.5% sorbitol is added to the microspore embryo medium (osmotic potential = 25.5 bars). Time course experiments, to study the induction of napin and cruciferin gene expression demonstrated that the ABA effect occurred much more rapidly than the high osmoticum effect, although after 48 hours, the levels of napin or cruciferin mRNA detected were similar in both treatments. This difference in the rates of induction is consistent with the idea that the osmotic effect may be mediated by ABA which is synthesized in response to the reduced water potential. Measurements of ABA (by gas chromatography-mass spectrometry using [ 2 H 6 ]ABA as an internal standard) present in microspore embryos during sorbitol treatment and in embryos treated with 10 micromolar ABA were performed to investigate this possibility. Within 2 hours of culture on high osmoticum the level of ABA increased substantially and significantly above control and reached a maximum concentration within 24 hours. This elevated concentration was maintained for 48 hours after culturing and represents a sixfold increase over control embryos

  1. Abscisic acid pathway involved in the regulation of watermelon fruit ripening and quality trait evolution.

    Directory of Open Access Journals (Sweden)

    Yanping Wang

    Full Text Available Watermelon (Citrullus lanatus (Thunb. Matsum. & Nakai is a non-climacteric fruit. The modern sweet-dessert watermelon is the result of years of cultivation and selection for fruits with desirable qualities. To date, the mechanisms of watermelon fruit ripening, and the role of abscisic acid (ABA in this process, has not been well understood. We quantified levels of free and conjugated ABA contents in the fruits of cultivated watermelon (97103; C. lanatus subsp. vulgaris, semi-wild germplasm (PI179878; C. lanatus subsp. mucosospermus, and wild germplasm (PI296341-FR; C. lanatus subsp. lanatus. Results showed that ABA content in the fruits of 97103 and PI179878 increased during fruit development and ripening, but maintained a low steady state in the center flesh of PI296341-FR fruits. ABA levels in fruits were highest in 97103 and lowest in PI296341-FR, but no obvious differences in ABA levels were observed in seeds of these lines. Examination of 31 representative watermelon accessions, including different C. lanatus subspecies and ancestral species, showed a correlation between soluble solids content (SSC and ABA levels in ripening fruits. Furthermore, injection of exogenous ABA or nordihydroguaiaretic acid (NDGA into 97103 fruits promoted or inhibited ripening, respectively. Transcriptomic analyses showed that the expression levels of several genes involved in ABA metabolism and signaling, including Cla009779 (NCED, Cla005404 (NCED, Cla020673 (CYP707A, Cla006655 (UGT and Cla020180 (SnRK2, varied significantly in cultivated and wild watermelon center flesh. Three SNPs (-738, C/A; -1681, C/T; -1832, G/T in the promoter region of Cla020673 (CYP707A and one single SNP (-701, G/A in the promoter of Cla020180 (SnRK2 exhibited a high level of correlation with SSC variation in the 100 tested accessions. Our results not only demonstrate for the first time that ABA is involved in the regulation of watermelon fruit ripening, but also provide insights into

  2. Abscisic acid pathway involved in the regulation of watermelon fruit ripening and quality trait evolution.

    Science.gov (United States)

    Wang, Yanping; Guo, Shaogui; Tian, Shouwei; Zhang, Jie; Ren, Yi; Sun, Honghe; Gong, Guoyi; Zhang, Haiying; Xu, Yong

    2017-01-01

    Watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai) is a non-climacteric fruit. The modern sweet-dessert watermelon is the result of years of cultivation and selection for fruits with desirable qualities. To date, the mechanisms of watermelon fruit ripening, and the role of abscisic acid (ABA) in this process, has not been well understood. We quantified levels of free and conjugated ABA contents in the fruits of cultivated watermelon (97103; C. lanatus subsp. vulgaris), semi-wild germplasm (PI179878; C. lanatus subsp. mucosospermus), and wild germplasm (PI296341-FR; C. lanatus subsp. lanatus). Results showed that ABA content in the fruits of 97103 and PI179878 increased during fruit development and ripening, but maintained a low steady state in the center flesh of PI296341-FR fruits. ABA levels in fruits were highest in 97103 and lowest in PI296341-FR, but no obvious differences in ABA levels were observed in seeds of these lines. Examination of 31 representative watermelon accessions, including different C. lanatus subspecies and ancestral species, showed a correlation between soluble solids content (SSC) and ABA levels in ripening fruits. Furthermore, injection of exogenous ABA or nordihydroguaiaretic acid (NDGA) into 97103 fruits promoted or inhibited ripening, respectively. Transcriptomic analyses showed that the expression levels of several genes involved in ABA metabolism and signaling, including Cla009779 (NCED), Cla005404 (NCED), Cla020673 (CYP707A), Cla006655 (UGT) and Cla020180 (SnRK2), varied significantly in cultivated and wild watermelon center flesh. Three SNPs (-738, C/A; -1681, C/T; -1832, G/T) in the promoter region of Cla020673 (CYP707A) and one single SNP (-701, G/A) in the promoter of Cla020180 (SnRK2) exhibited a high level of correlation with SSC variation in the 100 tested accessions. Our results not only demonstrate for the first time that ABA is involved in the regulation of watermelon fruit ripening, but also provide insights into the

  3. Enterobacter sp. I-3, a bio-herbicide inhibits gibberellins biosynthetic pathway and regulates abscisic acid and amino acids synthesis to control plant growth.

    Science.gov (United States)

    Radhakrishnan, Ramalingam; Park, Jae-Man; Lee, In-Jung

    2016-12-01

    Very few bacterial species were identified as bio-herbicides for weed control. The present research was focused to elucidate the plant growth retardant properties of Enterobacter sp. I-3 during their interaction by determining the changes in endogenous photosynthetic pigments, plant hormones and amino acids. The two bacterial isolates I-4-5 and I-3 were used to select the superior bacterium for controlling weed seeds (Echinochloa crus-galli L. and Portulaca oleracea L.) germination. The post-inoculation of I-3 (Enterobacter sp. I-3) significantly inhibited the weeds seed germination than their controls. The mechanism of bacterium induced plant growth reduction was identified in lettuce treated with I-3 bacterium and compared their effects with known chemical herbicide, trinexapac-ethyl (TE). The treatment of I-3 and TE showed a significant inhibitory effect on shoot length, leaf number, leaf length, leaf width, shoot weight, root weight and chlorophyll content in lettuce seedlings. The endogenous gibberellins (GAs) and abscisic acid (ABA) analysis showed that Enterobacter sp. I-3 treated plants had lower levels of GAs (GA 12 , GA 19 , GA 20 and GA 8 ) and GAs/ABA ratio and then, the higher level of ABA when compared to their controls. Indeed, the individual amino acids ie., aspartic acid, glutamic acid, glycine, threonine, alanine, serine, leucine, isoleucine and tyrosine were declined in TE and I-3 exposed plants. Our results suggest that the utilization of Enterobacter sp. I-3 inhibits the GAs pathway and amino acids synthesis in weeds to control their growth can be an alternative to chemical herbicides. Copyright © 2016 Elsevier GmbH. All rights reserved.

  4. Interaction of Polyamines, Abscisic Acid, Nitric Oxide, and Hydrogen Peroxide under Chilling Stress in Tomato (Lycopersicon esculentum Mill.) Seedlings

    OpenAIRE

    Diao, Qiannan; Song, Yongjun; Shi, Dongmei; Qi, Hongyan

    2017-01-01

    Polyamines (PAs) play a vital role in the responses of higher plants to abiotic stresses. However, only a limited number of studies have examined the interplay between PAs and signal molecules. The aim of this study was to elucidate the cross-talk among PAs, abscisic acid (ABA), nitric oxide (NO), and hydrogen peroxide (H2O2) under chilling stress conditions using tomato seedlings [(Lycopersicon esculentum Mill.) cv. Moneymaker]. The study showed that during chilling stress (4°C; 0, 12, and 2...

  5. The p450 monooxygenase BcABA1 is essential for abscisic acid biosynthesis in Botrytis cinerea

    DEFF Research Database (Denmark)

    Siewers, V.; Smedsgaard, Jørn; Tudzynski, P.

    2004-01-01

    The phytopathogenic ascomycete Botrytis cinerea is known to produce abscisic acid (ABA), which is thought to be involved in host-pathogen interaction. Biochemical analyses had previously shown that, in contrast to higher plants, the fungal ABA biosynthesis probably does not proceed via carotenoids...... but involves direct cyclization of farnesyl diphosphate and subsequent oxidation steps. We present here evidence that this "direct" pathway is indeed the only one used by an ABA-overproducing strain of B. cinerea. Targeted inactivation of the gene bccpr1 encoding a cytochrome P450 oxidoreductase reduced...

  6. Altered cytokinin metabolism affects cytokinin, auxin, and abscisic acid contents in leaves and chloroplasts, and chloroplast ultrastructure in transgenic tobacco

    Czech Academy of Sciences Publication Activity Database

    Polanská, Lenka; Vičánková, Anna; Nováková, Marie; Malbeck, Jiří; Dobrev, Petre; Brzobohatý, Břetislav; Vaňková, Radomíra; Macháčková, Ivana

    2007-01-01

    Roč. 58, č. 3 (2007), s. 637-649 ISSN 0022-0957 R&D Projects: GA ČR GA206/03/0369; GA ČR GA206/06/1306; GA AV ČR IAA600040612 Institutional research plan: CEZ:AV0Z50380511; CEZ:AV0Z50040507 Source of funding: V - iné verejné zdroje ; V - iné verejné zdroje Keywords : abscisic acid * auxin * chloroplast ultrastructure Subject RIV: EF - Botanics Impact factor: 3.917, year: 2007

  7. Variation in abscisic acid responsiveness of Aegilops tauschii and hexaploid wheat synthetics due to the D-genome diversity.

    Science.gov (United States)

    Iehisa, Julio C M; Takumi, Shigeo

    2012-01-01

    Common wheat (Triticum aestivum L.) is an allohexaploid that originated from natural hybridization between tetraploid wheat (Triticum turgidum) and diploid Aegilops tauschii. Ae. tauschii is considered one of the potential sources of new genetic variation in abiotic stress tolerance for improving common wheat. Abscisic acid (ABA) plays an important role in plant adaptation to environmental stresses. In this study, ABA responsiveness of 67 Ae. tauschii accessions and their synthetic hexaploid wheat lines, derived from crosses between T. turgidum cv. Langdon and the Ae. tauschii accessions, was evaluated based on growth inhibition by 20 µM ABA. Wide variation was found in ABA responsiveness for both synthetic wheat lines and their parental Ae. tauschii accessions. The variations due to D-genome found at the diploid level were also expressed in a hexaploid genetic background. Two pairs of synthetic wheat lines differing in ABA responsiveness were then selected for gene expression analysis and to test abiotic stress tolerance, because their parental Ae. tauschii accessions similarly exhibited the differential response to ABA. Gene expression of ABA inducible transcription factor, WABI5, and the downstream Cor/Lea genes (Wrab17, Wdhn13 and Wrab18) were analysed. In one pair, the highly responsive line exhibited higher induction of Wrab17 by ABA treatment, but no significant difference in dehydration or salinity tolerance was observed between these lines. In contrast, in the second pair, the highly ABA-responsive line showed higher levels of Wdhn13 expression and dehydration and salinity tolerance. In synthetic wheat lines, the difference in the ABA responsiveness of the lines appeared to be determined by the different sets of D-genome genes. Our findings suggest that highly ABA-responsive Ae. tauschii accessions should be valuable genetic resources for improving the abiotic stress tolerance of common wheat.

  8. Abscinazole-E3M, a practical inhibitor of abscisic acid 8′-hydroxylase for improving drought tolerance

    Science.gov (United States)

    Takeuchi, Jun; Okamoto, Masanori; Mega, Ryosuke; Kanno, Yuri; Ohnishi, Toshiyuki; Seo, Mitsunori; Todoroki, Yasushi

    2016-01-01

    Abscisic acid (ABA) is an essential phytohormone that regulates plant water use and drought tolerance. However, agricultural applications of ABA have been limited because of its rapid inactivation in plants, which involves hydroxylation of ABA by ABA 8′-hydroxylase (CYP707A). We previously developed a selective inhibitor of CYP707A, (−)-Abz-E2B, by structurally modifying S-uniconazole, which functions as an inhibitor of CYP707A and as a gibberellin biosynthetic enzyme. However, its synthetic yield is too low for practical applications. Therefore, we designed novel CYP707A inhibitors, Abz-T compounds, that have simpler structures in which the 1,2,3-triazolyl ring of (−)-Abz-E2B has been replaced with a triple bond. They were successfully synthesised in shorter steps, resulting in greater yields than that of (−)-Abz-E2B. In the enzymatic assays, one of the Abz-T compounds, (−)-Abz-E3M, acted as a strong and selective inhibitor of CYP707A, similar to (−)-Abz-E2B. Analysis of the biological effects in Arabidopsis revealed that (−)-Abz-E3M enhanced ABA’s effects more than (−)-Abz-E2B in seed germination and in the expression of ABA-responsive genes. Treatment with (−)-Abz-E3M induced stomatal closure and improved drought tolerance in Arabidopsis. Furthermore, (−)-Abz-E3M also increased the ABA response in rice and maize. Thus, (−)-Abz-E3M is a more practical and effective inhibitor of CYP707A than (−)-Abz-E2B. PMID:27841331

  9. Abscinazole-E3M, a practical inhibitor of abscisic acid 8'-hydroxylase for improving drought tolerance.

    Science.gov (United States)

    Takeuchi, Jun; Okamoto, Masanori; Mega, Ryosuke; Kanno, Yuri; Ohnishi, Toshiyuki; Seo, Mitsunori; Todoroki, Yasushi

    2016-11-14

    Abscisic acid (ABA) is an essential phytohormone that regulates plant water use and drought tolerance. However, agricultural applications of ABA have been limited because of its rapid inactivation in plants, which involves hydroxylation of ABA by ABA 8'-hydroxylase (CYP707A). We previously developed a selective inhibitor of CYP707A, (-)-Abz-E2B, by structurally modifying S-uniconazole, which functions as an inhibitor of CYP707A and as a gibberellin biosynthetic enzyme. However, its synthetic yield is too low for practical applications. Therefore, we designed novel CYP707A inhibitors, Abz-T compounds, that have simpler structures in which the 1,2,3-triazolyl ring of (-)-Abz-E2B has been replaced with a triple bond. They were successfully synthesised in shorter steps, resulting in greater yields than that of (-)-Abz-E2B. In the enzymatic assays, one of the Abz-T compounds, (-)-Abz-E3M, acted as a strong and selective inhibitor of CYP707A, similar to (-)-Abz-E2B. Analysis of the biological effects in Arabidopsis revealed that (-)-Abz-E3M enhanced ABA's effects more than (-)-Abz-E2B in seed germination and in the expression of ABA-responsive genes. Treatment with (-)-Abz-E3M induced stomatal closure and improved drought tolerance in Arabidopsis. Furthermore, (-)-Abz-E3M also increased the ABA response in rice and maize. Thus, (-)-Abz-E3M is a more practical and effective inhibitor of CYP707A than (-)-Abz-E2B.

  10. Roles of Gibberellins and Abscisic Acid in Regulating Germination of Suaeda salsa Dimorphic Seeds Under Salt Stress.

    Science.gov (United States)

    Li, Weiqiang; Yamaguchi, Shinjiro; Khan, M Ajmal; An, Ping; Liu, Xiaojing; Tran, Lam-Son P

    2015-01-01

    Seed heteromorphism observed in many halophytes is an adaptive phenomenon toward high salinity. However, the relationship between heteromorphic seed germination and germination-related hormones under salt stress remains elusive. To gain an insight into this relationship, the roles of gibberellins (GAs) and abscisic acid (ABA) in regulating germination of Suaeda salsa dimorphic brown and black seeds under salinity were elucidated by studying the kinetics of the two hormones during germination of the two seed types with or without salinity treatment. Morphological analysis suggested that brown and black are in different development stage. The content of ABA was higher in dry brown than in black seeds, which gradually decreased after imbibition in water and salt solutions. Salt stress induced ABA accumulation in both germinating seed types, with higher induction effect on black than brown seeds. Black seeds showed lower germination percentage than brown seeds under both water and salt stress, which might be attributed to their higher ABA sensitivity rather than the difference in ABA content between black and brown seeds. Bioactive GA4 and its biosynthetic precursors showed higher levels in brown than in black seeds, whereas deactivated GAs showed higher content in black than brown seeds in dry or in germinating water or salt solutions. High salinity inhibited seed germination through decreasing the levels of GA4 in both seeds, and the inhibited effect of salt stress on GA4 level of black seeds was more profound than that of brown seeds. Taken together higher GA4 content, and lower ABA sensitivity contributed to the higher germination percentage of brown seeds than black seeds in water and salinity; increased ABA content and sensitivity, and decreased GA4 content by salinity were more profound in black than brown seeds, which contributed to lower germination of black seeds than brown seeds in salinity. The differential regulation of ABA and GA homeostases by salt

  11. Response of chickpea (Cicer arietinum L.) to terminal drought: leaf stomatal conductance, pod abscisic acid concentration, and seed set.

    Science.gov (United States)

    Pang, Jiayin; Turner, Neil C; Khan, Tanveer; Du, Yan-Lei; Xiong, Jun-Lan; Colmer, Timothy D; Devilla, Rosangela; Stefanova, Katia; Siddique, Kadambot H M

    2017-04-01

    Flower and pod production and seed set of chickpea (Cicer arietinum L.) are sensitive to drought stress. A 2-fold range in seed yield was found among a large number of chickpea genotypes grown at three dryland field sites in south-western Australia. Leaf water potential, photosynthetic characteristics, and reproductive development of two chickpea genotypes with contrasting yields in the field were compared when subjected to terminal drought in 106kg containers of soil in a glasshouse. The terminal drought imposed from early podding reduced biomass, reproductive growth, harvest index, and seed yield of both genotypes. Terminal drought at least doubled the percentage of flower abortion, pod abscission, and number of empty pods. Pollen viability and germination decreased when the fraction of transpirable soil water (FTSW) decreased below 0.18 (82% of the plant-available soil water had been transpired); however, at least one pollen tube in each flower reached the ovary. The young pods which developed from flowers produced when the FTSW was 0.50 had viable embryos, but contained higher abscisic acid (ABA) concentrations than those of the well-watered plants; all pods ultimately aborted in the drought treatment. Cessation of seed set at the same soil water content at which stomata began to close and ABA increased strongly suggested a role for ABA signalling in the failure to set seed either directly through abscission of developing pods or seeds or indirectly through the reduction of photosynthesis and assimilate supply to the seeds. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  12. The role of zeatin and gibberellic acid in breaking of the abscisic acid-induced dormancy in Triticale caryopses

    Directory of Open Access Journals (Sweden)

    Stanisław Weidner

    2014-01-01

    Full Text Available The investigations were conducted on the germinating embryos and the whole caryopses of Triticale. During preimbibition and 24 hours germination caryopses were treated with abscisic acid (ABA, which produced 63% inhibition of embryo growth. Gibberellin-A3 (GA3 reversed the ABA effect in 18%, while zeatin in 22%. The clear synergic reaction was observed (36% when both stimulators acted together. There was no significant effect of ABA, ABA and GA3, as well as ABA and zeatin on the synthesis of polyribosomal RNA in the initial period of germination of excised embryos. However, during 24 hours germination of whole caryopses ABA caused a twofold decrease in 3H-uridine incorporation into the total fraction of embryonic ribosomes. While the incorporation of 14C-aminoacid mixture into ribosomal proteins was even three-fold lower. Effect of GA3 and zeatin on breaking of the ABA-induced "dormancy" was studied. It was confirmed that the higher polyribosome contribution to the sum total of ribosomes the more intensive synthesis of ribosomal proteins. No higher 3H-uridine incorporation into polyribosomal fraction was observed. From the results it may be inferred that in the initial period of germination of Triticale caryopses regulation of protein biosynthesis occurs rather at the translation than transcription level.

  13. Arabidopsis cysteine-rich receptor-like kinase 45 functions in the responses to abscisic acid and abiotic stresses

    KAUST Repository

    Zhang, Xiujuan

    2013-06-01

    The phytohormone abscisic acid (ABA) regulates seed germination, plant growth and development, and response to abiotic stresses such as drought and salt stresses. Receptor-like kinases are well known signaling components that mediate plant responses to developmental and environmental stimuli. Here, we characterized the biological function of an ABA and stress-inducible cysteine-rich receptor-like protein kinase, CRK45, in ABA signaling in Arabidopsis thaliana. The crk45 mutant was less sensitive to ABA than the wild type during seed germination and early seedling development, whereas CRK45 overexpression plants were more sensitive to ABA compared to the wild type. Furthermore, overexpression of CRK45 led to hypersensitivity to salt and glucose inhibition of seed germination, whereas the crk45 mutant showed the opposite phenotypes. In addition, CRK45 overexpression plants had enhanced tolerance to drought. Gene expression analyses revealed that the expression of representative stress-responsive genes was significantly enhanced in CRK45 overexpression plants in response to salt stress. ABA biosynthetic genes such as NCED3,. 22NCED3, 9-Cis-Epoxycarotenoid Dioxygenase 3.NCED5,. 33NCED5, 9-Cis-Epoxycarotenoid Dioxygenase 5.ABA2,. 44ABA2, Abscisic Acid Deficient 2. and AAO355AAO3, Abscisic Aldehyde Oxidase 3. were also constitutively elevated in the CRK45 overexpression plants. We concluded that CRK45 plays an important role in ABA signaling that regulates Arabidopsis seeds germination, early seedling development and abiotic stresses response, by positively regulating ABA responses in these processes. © 2013 Elsevier Masson SAS.

  14. Transcriptional regulatory programs underlying barley germination and regulatory functions of Gibberellin and abscisic acid

    Science.gov (United States)

    2011-01-01

    Background Seed germination is a complex multi-stage developmental process, and mainly accomplished through concerted activities of many gene products and biological pathways that are often subjected to strict developmental regulation. Gibberellins (GA) and abscisic acid (ABA) are two key phytohormones regulating seed germination and seedling growth. However, transcriptional regulatory networks underlying seed germination and its associated biological pathways are largely unknown. Results The studies examined transcriptomes of barley representing six distinct and well characterized germination stages and revealed that the transcriptional regulatory program underlying barley germination was composed of early, late, and post-germination phases. Each phase was accompanied with transcriptional up-regulation of distinct biological pathways. Cell wall synthesis and regulatory components including transcription factors, signaling and post-translational modification components were specifically and transiently up-regulated in early germination phase while histone families and many metabolic pathways were up-regulated in late germination phase. Photosynthesis and seed reserve mobilization pathways were up-regulated in post-germination phase. However, stress related pathways and seed storage proteins were suppressed through the entire course of germination. A set of genes were transiently up-regulated within three hours of imbibition, and might play roles in initiating biological pathways involved in seed germination. However, highly abundant transcripts in dry barley and Arabidopsis seeds were significantly conserved. Comparison with transcriptomes of barley aleurone in response to GA and ABA identified three sets of germination responsive genes that were regulated coordinately by GA, antagonistically by ABA, and coordinately by GA but antagonistically by ABA. Major CHO metabolism, cell wall degradation and protein degradation pathways were up-regulated by both GA and seed

  15. Arabidopsis AtDjA3 null mutant shows increased sensitivity to abscisic acid, salt, and osmotic stress in germination and postgermination stages

    Directory of Open Access Journals (Sweden)

    Silvia eSalas-Muñoz

    2016-02-01

    Full Text Available DnaJ proteins are essential co-chaperones involved in abiotic and biotic stress responses. Arabidopsis AtDjA3 gene encodes a molecular co-chaperone of 420 amino acids, which belongs to the J-protein family. In this study, we report the functional characterization of the AtDjA3 gene using the Arabidopsis knockout line designated j3 and the 35S::AtDjA3 overexpression lines. Loss of AtDjA3 function was associated with small seed production. In fact, j3 mutant seeds showed a reduction of 24% in seed weight compared to Col-0 seeds. Expression analysis showed that the AtDjA3 gene was modulated in response to NaCl, glucose, and abscisic acid. The j3 line had increased sensitivity to NaCl and glucose treatments in the germination and cotyledon development in comparison to parental Col-0. Furthermore, the j3 mutant line exhibited higher abscisic acid sensitivity in comparison to parental Col-0 and 35S::AtDjA3 overexpression lines. In addition, we examined the expression of ABI3 gene, which is a central regulator in ABA signalling, in j3 mutant and 35S::AtDjA3 overexpression lines. Under 5 μM ABA treatment at 24 h, j3 mutant seedlings displayed higher ABI3 expression, whereas in 35S::AtDjA3 overexpression lines, ABI3 gene expression was repressed. Taken together, these results demonstrate that the AtDjA3 gene is involved in seed development and abiotic stress tolerance.

  16. Arabidopsis seed-specific vacuolar aquaporins are involved in maintaining seed longevity under the control of ABSCISIC ACID INSENSITIVE 3.

    Science.gov (United States)

    Mao, Zhilei; Sun, Weining

    2015-08-01

    The tonoplast intrinsic proteins TIP3;1 and TIP3;2 are specifically expressed during seed maturation and localized to the seed protein storage vacuole membrane. However, the function and physiological roles of TIP3s are still largely unknown. The seed performance of TIP3 knockdown mutants was analysed using the controlled deterioration test. The tip3;1/tip3;2 double mutant was affected in seed longevity and accumulated high levels of hydrogen peroxide compared with the wild type, suggesting that TIP3s function in seed longevity. The transcription factor ABSCISIC ACID INSENSITIVE 3 (ABI3) is known to be involved in seed desiccation tolerance and seed longevity. TIP3 transcript and protein levels were significantly reduced in abi3-6 mutant seeds. TIP3;1 and TIP3;2 promoters could be activated by ABI3 in the presence of abscisic acid (ABA) in Arabidopsis protoplasts. TIP3 proteins were detected in the protoplasts transiently expressing ABI3 and in ABI3-overexpressing seedlings when treated with ABA. Furthermore, ABI3 directly binds to the RY motif of the TIP3 promoters. Therefore, seed-specific TIP3s may help maintain seed longevity under the expressional control of ABI3 during seed maturation and are members of the ABI3-mediated seed longevity pathway together with small heat shock proteins and late embryo abundant proteins. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  17. Detection of phytohormones in temperate forest fungi predicts consistent abscisic acid production and a common pathway for cytokinin biosynthesis.

    Science.gov (United States)

    Morrison, Erin N; Knowles, Sarah; Hayward, Allison; Thorn, R Greg; Saville, Barry J; Emery, R J N

    2015-01-01

    The phytohormones, abscisic acid and cytokinin, once were thought to be present uniquely in plants, but increasing evidence suggests that these hormones are present in a wide variety of organisms. Few studies have examined fungi for the presence of these "plant" hormones or addressed whether their levels differ based on the nutrition mode of the fungus. This study examined 20 temperate forest fungi of differing nutritional modes (ectomycorrhizal, wood-rotting, saprotrophic). Abscisic acid and cytokinin were present in all fungi sampled; this indicated that the sampled fungi have the capacity to synthesize these two classes of phytohormones. Of the 27 cytokinins analyzed by HPLC-ESI MS/MS, seven were present in all fungi sampled. This suggested the existence of a common cytokinin metabolic pathway in fungi that does not vary among different nutritional modes. Predictions regarding the source of isopentenyl, cis-zeatin and methylthiol CK production stemming from the tRNA degradation pathway among fungi are discussed. © 2015 by The Mycological Society of America.

  18. 1-Aminocyclopropane-1-carboxylic acid and abscisic acid during the germination of sugar beet (Beta vulgaris L.): a comparative study of fruits and seeds.

    Science.gov (United States)

    Hermann, Katrin; Meinhard, Juliane; Dobrev, Peter; Linkies, Ada; Pesek, Bedrich; Hess, Barbara; Machácková, Ivana; Fischer, Uwe; Leubner-Metzger, Gerhard

    2007-01-01

    The control of sugar beet (Beta vulgaris L.) germination by plant hormones was studied by comparing fruits and seeds. Treatment of sugar beet fruits and seeds with gibberellins, brassinosteroids, auxins, cytokinins, and jasmonates or corresponding hormone biosynthesis inhibitors did not appreciably affect radicle emergence of fruits or seeds. By contrast, treatment with ethylene or the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) promoted radicle emergence of fruits and seeds. Abscisic acid (ABA) acted as an antagonist of ethylene and inhibited radicle emergence of seeds, but not appreciably of fruits. High endogenous contents of ACC and of ABA were evident in seeds and pericarps of dry mature fruits, but declined early during imbibition. ABA-treatment of seeds and fruits induced seed ACC accumulation while ACC-treatment did not affect the seed ABA content. Transcripts of ACC oxidase (ACO, ethylene-forming enzyme) and ABA 8'-hydroxylase (CYP707A, ABA-degrading enzyme) accumulate in fruits and seeds upon imbibition. ABA and ACC and the pericarp did not affect the seed CYP707A transcript levels. By contrast, seed ACO transcript accumulation was promoted by ABA and by pericarp removal, but not by ACC. Quantification of the endogenous ABA and ACC contents, ABA and ACC leaching, and ethylene evolution, demonstrate that an embryo-mediated active ABA extrusion system is involved in keeping the endogenous seed ABA content low by 'active ABA leaching', while the pericarp restricts ACC leaching during imbibition. Sugar beet radicle emergence appears to be controlled by the pericarp, by ABA and ACC leaching, and by an ABA-ethylene antagonism that affects ACC biosynthesis and ACO gene expression.

  19. Up-regulation of abscisic acid signaling pathway facilitates aphid xylem absorption and osmoregulation under drought stress

    Science.gov (United States)

    Guo, Huijuan; Sun, Yucheng; Peng, Xinhong; Wang, Qinyang; Harris, Marvin; Ge, Feng

    2016-01-01

    The activation of the abscisic acid (ABA) signaling pathway reduces water loss from plants challenged by drought stress. The effect of drought-induced ABA signaling on the defense and nutrition allocation of plants is largely unknown. We postulated that these changes can affect herbivorous insects. We studied the effects of drought on different feeding stages of pea aphids in the wild-type A17 of Medicago truncatula and ABA signaling pathway mutant sta-1. We examined the impact of drought on plant water status, induced plant defense signaling via the abscisic acid (ABA), jasmonic acid (JA), and salicylic acid (SA) pathways, and on the host nutritional quality in terms of leaf free amino acid content. During the penetration phase of aphid feeding, drought decreased epidermis/mesophyll resistance but increased mesophyll/phloem resistance of A17 but not sta-1 plants. Quantification of transcripts associated with ABA, JA and SA signaling indicated that the drought-induced up-regulation of ABA signaling decreased the SA-dependent defense but increased the JA-dependent defense in A17 plants. During the phloem-feeding phase, drought had little effect on the amino acid concentrations and the associated aphid phloem-feeding parameters in both plant genotypes. In the xylem absorption stage, drought decreased xylem absorption time of aphids in both genotypes because of decreased water potential. Nevertheless, the activation of the ABA signaling pathway increased water-use efficiency of A17 plants by decreasing the stomatal aperture and transpiration rate. In contrast, the water potential of sta-1 plants (unable to close stomata) was too low to support xylem absorption activity of aphids; the aphids on sta-1 plants had the highest hemolymph osmolarity and lowest abundance under drought conditions. Taken together this study illustrates the significance of cross-talk between biotic-abiotic signaling pathways in plant-aphid interaction, and reveals the mechanisms leading to alter

  20. Interaction of Polyamines, Abscisic Acid, Nitric Oxide, and Hydrogen Peroxide under Chilling Stress in Tomato (Lycopersicon esculentumMill.) Seedlings.

    Science.gov (United States)

    Diao, Qiannan; Song, Yongjun; Shi, Dongmei; Qi, Hongyan

    2017-01-01

    Polyamines (PAs) play a vital role in the responses of higher plants to abiotic stresses. However, only a limited number of studies have examined the interplay between PAs and signal molecules. The aim of this study was to elucidate the cross-talk among PAs, abscisic acid (ABA), nitric oxide (NO), and hydrogen peroxide (H 2 O 2 ) under chilling stress conditions using tomato seedlings [( Lycopersicon esculentum Mill.) cv. Moneymaker]. The study showed that during chilling stress (4°C; 0, 12, and 24 h), the application of spermidine (Spd) and spermine (Spm) elevated NO and H 2 O 2 levels, enhanced nitrite reductase (NR), nitric oxide synthase (NOS)-like, and polyamine oxidase activities, and upregulated LeNR relative expression, but did not influence LeNOS1 expression. In contrast, putrescine (Put) treatment had no obvious impact. During the recovery period (25/15°C, 10 h), the above-mentioned parameters induced by the application of PAs were restored to their control levels. Seedlings pretreated with sodium nitroprusside (SNP, an NO donor) showed elevated Put and Spd levels throughout the treatment period, consistent with increased expression in leaves of genes encoding arginine decarboxylase ( LeADC. LeADC1 ), ornithine decarboxylase ( LeODC ), and Spd synthase ( LeSPDS ) expressions in tomato leaves throughout the treatment period. Under chilling stress, the Put content increased first, followed by a rise in the Spd content. Exogenously applied SNP did not increase the expression of genes encoding S -adenosylmethionine decarboxylase ( LeSAMDC ) and Spm synthase ( LeSPMS ), consistent with the observation that Spm levels remained constant under chilling stress and during the recovery period. In contrast, exogenous Put significantly increased the ABA content and the 9- cis -epoxycarotenoid dioxygenase ( LeNCED1 ) transcript level. Treatment with ABA could alleviate the electrolyte leakage (EL) induced by D-Arg (an inhibitor of Put). Taken together, it is

  1. [The ABC of abscisic acid action in plant drought stress responses].

    Science.gov (United States)

    Leung, Jeffrey; Valon, Christiane; Moreau, Bertrand; Boeglin, Martin; Lefoulon, Cécile; Joshi-Saha, Archana; Chérel, Isabelle

    2012-01-01

    The combined daily consumption of fresh water ranges from 200 to 700 liters per capita per day in most developed countries, with about 70% being used for agricultural needs. Unlike other resources such as the different forms of energy, water has no other alternatives. With the looming prospect of global water crisis, the recent laudable success in deciphering the early steps in the signal transduction of the "stress hormone" abscisic acid (ABA) has ignited hopes that crops can be engineered with the capacity to maintain productivity while requiring less water input. Although ABA was first discovered in plants, it has resurfaced in the human brain (and many other non-plant organisms : sea sponge, some parasites, hydra to name a few), suggesting that its existence may be widespread. In humans, more amazingly, ABA has shown anti-inflammatory and antiviral properties. Even its receptors and key signaling intermediates have homologs in the human genome suggesting that evolution has re-fashioned these same proteins into new functional contexts. Thus, learning about the molecular mechanisms of ABA in action using the more flexible plant model will be likely beneficial to other organisms, and especially in human diseases, which is topical in the medical circle. ABA can accumulate up to 10 to 30-fold in plants under drought stress relative to unstressed conditions. The built up of the hormone then triggers diverse adaptive pathways permitting plants to withstand temporary bouts of water shortage. One favorite experimental model to unravel ABA signaling mechanisms in all of its intimate detail is based on the hormone's ability to elicit stomatal closure - a rapid cellular response of land plants to limit water loss through transpiration. Each microscopic stoma, or pore, is contoured by two specialized kidney-shaped cells called the guard cells. Because land plants are protected by a waxy cuticle impermeable to gas exchange, the stomatal pores are thus the primary portals for

  2. Abscisic acid metabolite profiling as indicators of plastic responses to drought in grasses from arid Patagonian Monte (Argentina).

    Science.gov (United States)

    Cenzano, Ana M; Masciarelli, O; Luna, M Virginia

    2014-10-01

    The identification of hormonal and biochemical traits that play functional roles in the adaptation to drought is necessary for the conservation and planning of rangeland management. The aim of this study was to evaluate the effects of drought on i) the water content (WC) of different plant organs, ii) the endogenous level of abscisic acid (ABA) and metabolites (phaseic acid-PA, dihydrophaseic acid-DPA and abscisic acid conjugated with glucose ester-ABA-GE), iii) the total carotenoid concentration and iv) to compare the traits of two desert perennial grasses (Pappostipa speciosa and Poa ligularis) with contrasting morphological and functional drought resistance traits and life-history strategies. Both species were subjected to two levels of gravimetric soil moisture (the highest near field capacity during autumn-winter and the lowest corresponding to summer drought). Drought significantly increased the ABA and DPA levels in the green leaves of P. speciosa and P. ligularis. Drought decreased ABA in the roots of P. speciosa while it increased ABA in the roots of P. ligularis. P. ligularis had the highest ABA level and WC in green leaves. While P. speciosa had the highest DPA levels in leaves. In conclusion, we found the highest ABA level in the mesophytic species P. ligularis and the lowest ABA level in the xerophytic species P. speciosa, revealing that the ABA metabolite profile in each grass species is a plastic response to drought resistance. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  3. The putative E3 ubiquitin ligase ECERIFERUM9 regulates abscisic acid biosynthesis and response during seed germination and postgermination growth in arabidopsis

    KAUST Repository

    Zhao, Huayan

    2014-05-08

    The ECERIFERUM9 (CER9) gene encodes a putative E3 ubiquitin ligase that functions in cuticle biosynthesis and the maintenance of plant water status. Here, we found that CER9 is also involved in abscisic acid (ABA) signaling in seeds and young seedlings of Arabidopsis (Arabidopsis thaliana). The germinated embryos of the mutants exhibited enhanced sensitivity to ABA during the transition from reversible dormancy to determinate seedling growth. Expression of the CER9 gene is closely related to ABA levels and displays a similar pattern to that of ABSCISIC ACID-INSENSITIVE5 (ABI5), which encodes a positive regulator of ABA responses in seeds. cer9 mutant seeds exhibited delayed germination that is independent of seed coat permeability. Quantitative proteomic analyses showed that cer9 seeds had a protein profile similar to that of the wild type treated with ABA. Transcriptomics analyses revealed that genes involved in ABA biosynthesis or signaling pathways were differentially regulated in cer9 seeds. Consistent with this, high levels of ABA were detected in dry seeds of cer9. Blocking ABA biosynthesis by fluridone treatment or by combining an ABA-deficient mutation with cer9 attenuated the phenotypes of cer9. Whereas introduction of the abi1-1, abi3-1, or abi4-103 mutation could completely eliminate the ABA hypersensitivity of cer9, introduction of abi5 resulted only in partial suppression. These results indicate that CER9 is a novel negative regulator of ABA biosynthesis and the ABA signaling pathway during seed germination. © 2014 American Society of Plant Biologists. All Rights Reserved.

  4. Abscisic acid-induced nitric oxide and proline accumulation in independent pathways under water-deficit stress during seedling establishment in Medicago truncatula.

    Science.gov (United States)

    Planchet, Elisabeth; Verdu, Isabelle; Delahaie, Julien; Cukier, Caroline; Girard, Clément; Morère-Le Paven, Marie-Christine; Limami, Anis M

    2014-05-01

    Nitric oxide (NO) production and amino acid metabolism modulation, in particular abscisic acid (ABA)-dependent proline accumulation, are stimulated in planta by most abiotic stresses. However, the relationship between NO production and proline accumulation under abiotic stress is still poorly understood, especially in the early phases of plant development. To unravel this question, this work investigated the tight relationship between NO production and proline metabolism under water-deficit stress during seedling establishment. Endogenous nitrate reductase-dependent NO production in Medicago truncatula seedlings increased in a time-dependent manner after short-term water-deficit stress. This water-deficit-induced endogenous NO accumulation was mediated through a ABA-dependent pathway and accompanied by an inhibition of seed germination, a loss of water content, and a decrease in elongation of embryo axes. Interestingly, a treatment with a specific NO scavenger (cPTIO) alleviated these water-deficit detrimental effects. However, the content of total amino acids, in particular glutamate and proline, as well as the expression of genes encoding enzymes of synthesis and degradation of proline were not affected by cPTIO treatment under water-deficit stress. Under normal conditions, exogenous NO donor stimulated neither the expression of P5CS2 nor the proline content, as observed after PEG treatment. These results strongly suggest that the modulation of proline metabolism is independent of NO production under short-term water-deficit stress during seedling establishment.

  5. Reduced de-etiolation of hypocotyl growth in a tomato mutant is associated with hypersensitivity to, and high endogenous levels of, abscisic acid

    Czech Academy of Sciences Publication Activity Database

    Fellner, Martin; Zhang, R.; Pharis, R.; Sawhney, V.

    2001-01-01

    Roč. 52, č. 357 (2001), s. 725-738 ISSN 0022-0957 R&D Projects: GA ČR GV521/96/K117 Institutional research plan: CEZ:AV0Z5038910 Keywords : Abscisic acid * elongated mutant * fluridone Subject RIV: EF - Botanics Impact factor: 2.433, year: 2001

  6. Molecular and physiological responses of Iranian Perennial ryegrass as affected by Trinexapac ethyl, Paclobutrazol and Abscisic acid under drought stress.

    Science.gov (United States)

    Sheikh Mohammadi, Mohammad Hossein; Etemadi, Nematollah; Arab, Mohammad Mehdi; Aalifar, Mostafa; Arab, Mostafa; Pessarakli, Mohammad

    2017-02-01

    Drought stress is the major limiting factor which affects turfgrass management in area with restricted rainfall or irrigation water supply. Trinexapac ethyl (TE), Paclobutrazol (PAC) and Abscisic acid (ABA) are three plant growth regulators (PGRs) that are commonly used on turf species for increasing their tolerance to different environmental stresses such as drought. However, little is known about the impact of PGRs on stress tolerance of Iranian Perennial ryegrass (Lolium perenne). The present study was conducted to examine the visual and physiological changes of Iranian Perennial ryegrass in response to foliar application of TE, PAC, and ABA under drought stress conditions. According to the obtained results, application of all three PGRs considerably restored visual quality of drought exposed plants. TE treatment increased chlorophyll content, proline content and resulted in less malondialdehyde (MDA) in drought stressed Perennial ryegrass. Application of all PGRs enhanced the relative water content (RWC) and decreased the electrolyte leakage (EL) and Hydrogen peroxide contents (H 2 O 2 content) of plants under drought stress, though the impact of TE was more pronounced. Throughout the experiment, TE- and ABA-treated plant showed greater soluble sugar (SSC) content as compared to the control. Antioxidant enzymes activities of drought exposed plants were considerably increased by PGRs application. Catalase (CAT) and Superoxide dismutase (SOD) activities were greater in TE-treated grasses followed by PAC-treated plants. Ascorbate peroxidase (APX) and peroxidase (POD) activities were significantly enhanced by TE and ABA application. The results of the present investigation suggest that application of TE, ABA and PAC enhances drought tolerance in Perennial ryegrass. TE, PAC and ABA were all effective in mitigating physiological damages resulting from drought stress, however the beneficial effects of TE were more pronounced. The result obtained of real time

  7. The small ethylene response factor ERF96 is involved in the regulation of the abscisic acid response in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Xiaoping eWang

    2015-11-01

    Full Text Available Ethylene regulates many aspects of plant growth and development including seed germination, leaf senescence, and fruit ripening, and of plant responses to environmental stimuli including both biotic and abiotic stresses. Ethylene Response Factors (ERFs are plant-specific transcription factors and are a subfamily of the AP2 (APETALA2/ERF transcription factor family. The function of many members in this large gene family remains largely unknown. ERF96, a member of the Group IX ERF family transcription factors, has recently been shown to be a transcriptional activator that is involved in plant defense response in Arabidopsis. Here we provide evidence that ERF96 is a positive regulator of abscisic acid (ABA responses. Bioinformatics analysis indicated that there are a total four small ERFs in Arabidopsis including ERF95, ERF96, ERF97 and ERF98, and that ERF96 forms a cluster with ERF95 and ERF97. By using quantitative RT-PCR, we found that ERF96 is expressed in all tissues and organs examined except roots, with relatively high expression in flowers and seeds. Results from the protoplast transfection assay results indicated that the EDLL motif-containing C-terminal domain is responsible for ERF96’s transcriptional activity. Although loss-of-function mutant of ERF96 was morphologically similar to wild type plants, transgenic plants overexpressing ERF96 had smaller rosette size and were delayed in flowering time. In ABA sensitivity assays, we found that ERF96 overexpression plants were hypersensitive to ABA in terms of ABA inhibition of seed germination, early seedling development and root elongation. Consistent with these observations, elevated transcript levels of some ABA-responsive genes including RD29A, ABI5, ABF3, ABF4, P5CS and COR15A were observed in the transgenic plants in the presence of ABA. However, in the absence of ABA treatment, the transcript levels of these ABA-responsive genes remained largely unchanged. Our experiments also showed

  8. Analysis of ADP-glucose pyrophosphorylase expression during turion formation induced by abscisic acid in Spirodela polyrhiza (greater duckweed

    Directory of Open Access Journals (Sweden)

    Wang Wenqin

    2012-01-01

    Full Text Available Abstract Background Aquatic plants differ in their development from terrestrial plants in their morphology and physiology, but little is known about the molecular basis of the major phases of their life cycle. Interestingly, in place of seeds of terrestrial plants their dormant phase is represented by turions, which circumvents sexual reproduction. However, like seeds turions provide energy storage for starting the next growing season. Results To begin a characterization of the transition from the growth to the dormant phase we used abscisic acid (ABA, a plant hormone, to induce controlled turion formation in Spirodela polyrhiza and investigated their differentiation from fronds, representing their growth phase, into turions with respect to morphological, ultra-structural characteristics, and starch content. Turions were rich in anthocyanin pigmentation and had a density that submerged them to the bottom of liquid medium. Transmission electron microscopy (TEM of turions showed in comparison to fronds shrunken vacuoles, smaller intercellular space, and abundant starch granules surrounded by thylakoid membranes. Turions accumulated more than 60% starch in dry mass after two weeks of ABA treatment. To further understand the mechanism of the developmental switch from fronds to turions, we cloned and sequenced the genes of three large-subunit ADP-glucose pyrophosphorylases (APLs. All three putative protein and exon sequences were conserved, but the corresponding genomic sequences were extremely variable mainly due to the invasion of miniature inverted-repeat transposable elements (MITEs into introns. A molecular three-dimensional model of the SpAPLs was consistent with their regulatory mechanism in the interaction with the substrate (ATP and allosteric activator (3-PGA to permit conformational changes of its structure. Gene expression analysis revealed that each gene was associated with distinct temporal expression during turion formation. APL2 and

  9. A New Approach to Sequence Analysis Exemplified by Identification of cis-Elements in Abscisic Acid Inducible Promoters

    DEFF Research Database (Denmark)

    Busk, Peter Kamp; Hallin, Peter Fischer; Salomon, Jesper

    the sequences of known cis-elements for promoter prediction4. This is a computational alternative to genome-wide DNA array analysis of gene expression and can be used to confirm the importance of known promoter elements on a genome level. Unfortunately, this approach does not yield information about new cis....... These promoters were compared to 28000 promoters that are not induced by abscisic acid. The analysis identified previously described ABA-inducible promoter elements such as ABRE, CE3 and CRT1 but also new cis-elements were found. Furthermore, the list of DNA elements could be used to predict ABA......-inducible promoter with more than 70 % accuracy for the top 40 predictions, which is better than previously described methods4. In conclusion, identification of short, conserved motifs is a useful computational approach for identification of cis-elements in DNA promoters and for promoter prediction in genome...

  10. Functional characterization of a synthetic abscisic acid analog with anti-inflammatory activity on human granulocytes and monocytes.

    Science.gov (United States)

    Grozio, Alessia; Millo, Enrico; Guida, Lucrezia; Vigliarolo, Tiziana; Bellotti, Marta; Salis, Annalisa; Fresia, Chiara; Sturla, Laura; Magnone, Mirko; Galatini, Andrea; Damonte, Gianluca; De Flora, Antonio; Bruzzone, Santina; Bagnasco, Luca; Zocchi, Elena

    2011-12-02

    The phytohormone abscisic acid (ABA), in addition to regulating several important physiological functions in plants, is also produced and released by human granulocytes and monocytes where it stimulates cell activities involved in the innate immune response. Here we describe the properties of an ABA synthetic analog that competes with the hormone for binding to human granulocyte membranes and to purified recombinant LANCL2 (the human ABA receptor) and inhibits several ABA-triggered inflammatory functions of granulocytes and monocytes in vitro: chemotaxis, phagocytosis, reactive oxygen species production and release of prostaglandin E(2) (PGE(2)) by human granulocytes, release of PGE(2) and of monocyte chemoattractant protein-1 by human monocytes. This observation provides a proof of principle that ABA antagonists may represent a new class of anti-inflammatory agents. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Surviving a Dry Future: Abscisic Acid (ABA-Mediated Plant Mechanisms for Conserving Water under Low Humidity

    Directory of Open Access Journals (Sweden)

    Frances C. Sussmilch

    2017-11-01

    Full Text Available Angiosperms are able to respond rapidly to the first sign of dry conditions, a decrease in air humidity, more accurately described as an increase in the vapor pressure deficit between the leaf and the atmosphere (VPD, by abscisic acid (ABA-mediated stomatal closure. The genes underlying this response offer valuable candidates for targeted selection of crop varieties with improved drought tolerance, a critical goal for current plant breeding programs, to maximize crop production in drier and increasingly marginalized environments, and meet the demands of a growing population in the face of a changing climate. Here, we review current understanding of the genetic mechanisms underpinning ABA-mediated stomatal closure, a key means for conserving water under dry conditions, examine how these mechanisms evolved, and discuss what remains to be investigated.

  12. Structural Insights into Maize Viviparous14, a Key Enzyme in the Biosynthesis of the Phytohormone Abscisic Acid W

    Energy Technology Data Exchange (ETDEWEB)

    Messing, S.; Gabelli, S; Echeverria, I; Vogel, J; Guan, J; Tan, B; Klee, H; McCarty, D; Amzela, M

    2010-01-01

    The key regulatory step in the biosynthesis of abscisic acid (ABA), a hormone central to the regulation of several important processes in plants, is the oxidative cleavage of the 11,12 double bond of a 9-cis-epoxycarotenoid. The enzyme viviparous14 (VP14) performs this cleavage in maize (Zea mays), making it a target for the rational design of novel chemical agents and genetic modifications that improve plant behavior through the modulation of ABA levels. The structure of VP14, determined to 3.2-{angstrom} resolution, provides both insight into the determinants of regio- and stereospecificity of this enzyme and suggests a possible mechanism for oxidative cleavage. Furthermore, mutagenesis of the distantly related CCD1 of maize shows how the VP14 structure represents a template for all plant carotenoid cleavage dioxygenases (CCDs). In addition, the structure suggests how VP14 associates with the membrane as a way of gaining access to its membrane soluble substrate.

  13. Structural Insights into Maize Viviparous14, a Key Enzyme in the Biosynthesis of the Phytohormone Abscisic Acid

    Energy Technology Data Exchange (ETDEWEB)

    Messing, Simon A.J.; Gabelli, Sandra B.; Echeverria, Ignacia; Vogel, Jonathan T.; Guan, Jiahn Chou; Tan, Bao Cai; Klee, Harry J.; McCarty, Donald R.; Amzel, L. Mario (JHU); (Florida)

    2011-09-06

    The key regulatory step in the biosynthesis of abscisic acid (ABA), a hormone central to the regulation of several important processes in plants, is the oxidative cleavage of the 11,12 double bond of a 9-cis-epoxycarotenoid. The enzyme viviparous14 (VP14) performs this cleavage in maize (Zea mays), making it a target for the rational design of novel chemical agents and genetic modifications that improve plant behavior through the modulation of ABA levels. The structure of VP14, determined to 3.2-{angstrom} resolution, provides both insight into the determinants of regio- and stereospecificity of this enzyme and suggests a possible mechanism for oxidative cleavage. Furthermore, mutagenesis of the distantly related CCD1 of maize shows how the VP14 structure represents a template for all plant carotenoid cleavage dioxygenases (CCDs). In addition, the structure suggests how VP14 associates with the membrane as a way of gaining access to its membrane soluble substrate.

  14. Acclimation mechanisms elicited by sprayed abscisic acid, solar UV-B and water deficit in leaf tissues of field-grown grapevines.

    Science.gov (United States)

    Alonso, Rodrigo; Berli, Federico J; Bottini, Rubén; Piccoli, Patricia

    2015-06-01

    The independent and interactive effects of solar ultraviolet-B radiation (UV-B), moderate water deficit and sprayed abscisic acid (ABA) on leaves gas exchange and biochemical aspects of field-grown grapevines of the cv. Malbec were investigated in a high altitude vineyard (1450 m a.s.l.). Two UV-B treatments (ambient solar UV-B or reduced UV-B), two watering treatments (well watered or moderate water deficit) and two ABA treatments (no ABA and sprayed ABA) were given alone and combined in a factorial design. Gas exchange and photosynthesis were reduced by water deficit and highly impaired in the UV-B and water deficit combined treatment. UV-absorbing compounds were stimulated independently by UV-B. The monoterpenes α-pinene, 3-carene and terpinolene, and the sesquiterpene nerolidol were augmented by UV-B, water deficit or sprayed ABA. Levels of the triterpene squalene and the diterpene phytol were significantly higher in the treatment that combined UV-B, water deficit and ABA applications. Environment signals (solar UV-B and moderate water deficit) and sprayed ABA elicited mechanisms of acclimation by augmenting the content of terpenes with antioxidant and antifungal properties, thus enhancing the plant defensive mechanisms towards signals both biotic and abiotic. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  15. Flower inhibition in Kalanchoe blossfeldiana. Bioassay of an endogenous long-day inhibitor and inhibition by (±) abscisic acid and xanthoxin.

    Science.gov (United States)

    Schwabe, W W

    1972-03-01

    The inhibition of flowering in Kalanchoe by crude sap expressed from leaves held in non-inductive long-day conditions is described, using a bioassay technique of leaf injection, which confirms the existence of a transferable inhibitor.This technique has also revealed that ± abscisic acid and Xanthoxin are inhibitory to flowering at 50 and 100 ppm respectively. The previously known inhibitory effects of gibberellic acid on flowering have also been confirmed.

  16. Development of an ultrahigh-performance liquid chromatography-electrospray ionization-tandem mass spectrometry method for the simultaneous determination of salicylic acid, jasmonic acid, and abscisic acid in rose leaves.

    Science.gov (United States)

    Bosco, Renato; Daeseleire, Els; Van Pamel, Els; Scariot, Valentina; Leus, Leen

    2014-07-09

    This paper describes a method to detect and quantitate the endogenous plant hormones (±)-2-cis-4-trans-abscisic acid, (-)-jasmonic acid, and salicylic acid by means of ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) in hybrid rose leaf matrices. Deuterium-labeled [(2)H6] (+)-2-cis-4-trans-abscisic acid, [(2)H6] (±)-jasmonic acid, and [(2)H4]-salicylic acid were used as internal standards. Rose samples (10 mg) were extracted with methanol/water/acetic acid (10:89:1) and subsequently purified on an Oasis MCX 1 cm(3) Vac SPE cartridge. Performance characteristics were validated according to Commission Decision 2002/657/EC. Recovery, repeatability, and within-laboratory reproducibility were acceptable for all phytohormones tested at three different concentrations. The decision limit and detection capability for (±)-2-cis-4-trans-abscisic acid, (-)-jasmonic acid, and salicylic acid were 0.0075 and 0.015 μg/g, 0.00015 and 0.00030 μg/g, and 0.0089 and 0.018 μg/g, respectively. Matrix effects (signal suppression or enhancement) appeared to be high for all substances considered, implying the need for quantitation based on matrix-matched calibration curves.

  17. Solanum lycopersicum IAA15 functions in the 2,4-dichlorophenoxyacetic acid herbicide mechanism of action by mediating abscisic acid signalling.

    Science.gov (United States)

    Xu, Tao; Wang, Yanling; Liu, Xin; Gao, Song; Qi, Mingfang; Li, Tianlai

    2015-07-01

    2,4-Dichlorophenoxyacetic acid (2,4-D), an important plant growth regulator, is the herbicide most commonly used worldwide to control weeds. However, broad-leaf fruits and vegetables are extremely sensitive to herbicides, which can cause damage and result in lost crops when applied in a manner inconsistent with the directions. Despite detailed knowledge of the mechanism of 2,4-D, the regulation of auxin signalling is still unclear. For example, although the major mediators of auxin signalling, including auxin/indole acetic acid (AUX/IAA) proteins and auxin response factors (ARFs), are known to mediate auxinic herbicides, the underlying mechanisms are still unclear. In this study, the effects of 2,4-D on AUX/IAA gene expression in tomato were investigated, and the two most notably up-regulated genes, SlIAA15 and SlIAA29, were selected for further study. Western blotting revealed the substantial accumulation of both SlIAA15 and SlIAA29, and the expression levels of the corresponding genes were increased following abscisic acid (ABA) and ethylene treatment. Overexpressing SlIAA15, but not SlIAA29, induced a 2,4-D herbicide damage phenotype. The 35S::SlIAA15 line exhibited a strong reduction in leaf stomatal density and altered expression of some R2R3 MYB genes that are putatively involved in the regulation of stomatal differentiation. Further study revealed that root elongation in 35S::SlIAA15 was sensitive to ABA treatment, and was most probably due to the altered expression of an ABA signal transduction gene. In addition, the altered auxin sensitivities of SlIAA15 transformants were also explored. These results suggested that SlIAA15 plays an important role in determining the effects of the herbicide 2,4-D. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  18. Somatic embryogenesis in loblolly pine (Pinus taeda L.): improving culture initiation with abscisic acid and silver nitrate.

    Science.gov (United States)

    Pullman, G S; Namjoshi, K; Zhang, Y

    2003-09-01

    Loblolly pine ( Pinus taeda L.) culture initiation was improved by the addition of abscisic acid (ABA) (3.7 micro M), silver nitrate (20 micro M), and guanosine 3',5'-cyclic monophosphate, 8-bromo-, sodium salt (10 micro M) to the medium and by raising cytokinin levels in the presence of 50 mg/l activated carbon (AC). Basal medium contained modified 1/2-P6 salts, 50 mg/l AC, Cu and Zn added to compensate for adsorption by AC, 1.5% maltose, 2% myo-inositol, 500 mg/l casamino acids, 450 mg/l glutamine, 2 mg/l alpha-naphthaleneacetic acid (NAA), 0.55 mg/l 6-benzylaminopurine (BA), 0.53 mg/l kinetin, and 2 g/l Gelrite. Across 32 open-pollinated families initiation ranged from 0 to 53.4%, with an average of 17.9%. Further optimization of cytokinins to 0.63 mg/l BA and 0.61 mg/l kinetin along with the removal of ABA maintained initiation at 18.2% across 19 families. Survival of 2001 new initiations was tracked for 4-6 months. Survival averaged 28.8%. A test of 68 new initiations tracked closely for 4 months demonstrated that at least 80% of the cultures lost did not grow after transfer to the multiplication media, suggesting that many new initiations abort during the initiation process.

  19. Abscisic Acid Stimulates Glucagon-Like Peptide-1 Secretion from L-Cells and Its Oral Administration Increases Plasma Glucagon-Like Peptide-1 Levels in Rats.

    Science.gov (United States)

    Bruzzone, Santina; Magnone, Mirko; Mannino, Elena; Sociali, Giovanna; Sturla, Laura; Fresia, Chiara; Booz, Valeria; Emionite, Laura; De Flora, Antonio; Zocchi, Elena

    2015-01-01

    In recent years, Abscisic Acid (ABA) has been demonstrated to be involved in the regulation of glucose homeostasis in mammals as an endogenous hormone, by stimulating both insulin release and peripheral glucose uptake. In addition, ABA is released by glucose- or GLP-1-stimulated β-pancreatic cells. Here we investigated whether ABA can stimulate GLP-1 release. The human enteroendocrine L cell line hNCI-H716 was used to explore whether ABA stimulates in vitro GLP-1 secretion and/or transcription. ABA induced GLP-1 release in hNCI-H716 cells, through a cAMP/PKA-dependent mechanism. ABA also enhanced GLP-1 transcription. In addition, oral administration of ABA significantly increased plasma GLP-1 and insulin levels in rats. In conclusion, ABA can stimulate GLP-1 release: this result and the previous observation that GLP-1 stimulates ABA release from β -cells, suggest a positive feed-back mechanism between ABA and GLP-1, regulating glucose homeostasis. Type 2 diabetes treatments targeting the GLP-1 axis by either inhibiting its rapid clearance by dipeptidyl-peptidase IV or using GLP-1 mimetics are currently used. Moreover, the development of treatments aimed at stimulating GLP-1 release from L cells has been considered as an alternative approach. Accordingly, our finding that ABA increases GLP-1 release in vitro and in vivo may suggest ABA and/or ABA analogs as potential anti-diabetic treatments.

  20. Abscisic Acid Stimulates Glucagon-Like Peptide-1 Secretion from L-Cells and Its Oral Administration Increases Plasma Glucagon-Like Peptide-1 Levels in Rats.

    Directory of Open Access Journals (Sweden)

    Santina Bruzzone

    Full Text Available In recent years, Abscisic Acid (ABA has been demonstrated to be involved in the regulation of glucose homeostasis in mammals as an endogenous hormone, by stimulating both insulin release and peripheral glucose uptake. In addition, ABA is released by glucose- or GLP-1-stimulated β-pancreatic cells. Here we investigated whether ABA can stimulate GLP-1 release. The human enteroendocrine L cell line hNCI-H716 was used to explore whether ABA stimulates in vitro GLP-1 secretion and/or transcription. ABA induced GLP-1 release in hNCI-H716 cells, through a cAMP/PKA-dependent mechanism. ABA also enhanced GLP-1 transcription. In addition, oral administration of ABA significantly increased plasma GLP-1 and insulin levels in rats. In conclusion, ABA can stimulate GLP-1 release: this result and the previous observation that GLP-1 stimulates ABA release from β -cells, suggest a positive feed-back mechanism between ABA and GLP-1, regulating glucose homeostasis. Type 2 diabetes treatments targeting the GLP-1 axis by either inhibiting its rapid clearance by dipeptidyl-peptidase IV or using GLP-1 mimetics are currently used. Moreover, the development of treatments aimed at stimulating GLP-1 release from L cells has been considered as an alternative approach. Accordingly, our finding that ABA increases GLP-1 release in vitro and in vivo may suggest ABA and/or ABA analogs as potential anti-diabetic treatments.

  1. Overexpression of EsMcsu1 from the halophytic plant Eutrema salsugineum promotes abscisic acid biosynthesis and increases drought resistance in alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Zhou, C; Ma, Z Y; Zhu, L; Guo, J S; Zhu, J; Wang, J F

    2015-12-17

    The stress phytohormone abscisic acid (ABA) plays pivotal roles in plants' adaptive responses to adverse environments. Molybdenum cofactor sulfurases influence aldehyde oxidase activity and ABA biosynthesis. In this study, we isolated a novel EsMcsu1 gene encoding a molybdenum cofactor sulfurase from Eutrema salsugineum. EsMcus1 transcriptional patterns varied between organs, and its expression was significantly upregulated by abiotic stress or ABA treatment. Alfalfa plants that overexpressed EsMcsu1 had a higher ABA content than wild-type (WT) plants under drought stress conditions. Furthermore, levels of reactive oxygen species (ROS), ion leakage, and malondialdehyde were lower in the transgenic plants than in the WT plants after drought treatment, suggesting that the transgenic plants experienced less ROS-mediated damage. However, the expression of several stress-responsive genes, antioxidant enzyme activity, and osmolyte (proline and total soluble sugar) levels in the transgenic plants were higher than those in the WT plants after drought treatment. Therefore, EsMcsu1 overexpression improved drought tolerance in alfalfa plants by activating a series of ABA-mediated stress responses.

  2. Mutations in the Arabidopsis Lst8 and Raptor genes encoding partners of the TOR complex, or inhibition of TOR activity decrease abscisic acid (ABA) synthesis.

    Science.gov (United States)

    Kravchenko, Alena; Citerne, Sylvie; Jéhanno, Isabelle; Bersimbaev, Rakhmetkazhi I; Veit, Bruce; Meyer, Christian; Leprince, Anne-Sophie

    2015-11-27

    The Target of Rapamycin (TOR) kinase regulates essential processes in plant growth and development by modulation of metabolism and translation in response to environmental signals. In this study, we show that abscisic acid (ABA) metabolism is also regulated by the TOR kinase. Indeed ABA hormone level strongly decreases in Lst8-1 and Raptor3g mutant lines as well as in wild-type (WT) Arabidopsis plants treated with AZD-8055, a TOR inhibitor. However the growth and germination of these lines are more sensitive to exogenous ABA. The diminished ABA hormone accumulation is correlated with lower transcript levels of ZEP, NCED3 and AAO3 biosynthetic enzymes, and higher transcript amount of the CYP707A2 gene encoding a key-enzyme in abscisic acid catabolism. These results suggest that the TOR signaling pathway is implicated in the regulation of ABA accumulation in Arabidopsis. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Induction of protection against paraquat-induced oxidative damage by abscisic acid in maize leaves is mediated through mitogen-activated protein kinase.

    Science.gov (United States)

    Ding, Hai-Dong; Zhang, Xiao-Hua; Xu, Shu-Cheng; Sun, Li-Li; Jiang, Ming-Yi; Zhang, A-Ying; Jin, Yin-Gen

    2009-10-01

    Mitogen-activated protein kinase (MAPK) cascade has been shown to be important components in stress signal transduction pathway. In the present study, protection of maize seedlings (Zea mays L.) against paraquat-generated oxidative toxicity by abscisic acid (ABA), its association with MAPK and ZmMPK5, a candidate for MAPK were investigated. Treatment of maize leaves with exogenous ABA led to significant decreases in the content of malondialdehyde, the percentage of ion leakage and the level of protein oxidation (in terms of carbonyl groups) under paraquat (PQ) stress. However, such decreases were blocked by the pretreatment with two MAPK kinase inhibitors PD98059 and U0126. The damage caused by PQ was further aggravated by inhibitors. Two inhibitors also suppressed the total activities of the antioxidant enzymes superoxide dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC 1.11.1.6), ascorbate peroxidase (APX, EC 1.11.1.11), and glutathione reductase (GR, EC 1.6.4.2). Besides, treatment with PQ stimulated the activation of a 46 kDa MAPK, which was identified as ZmMPK5 by in-gel kinase assay with immunoprecipitation. These results reveal that ABA-induced protection against PQ-generated oxidative damage is mediated through MAPK cascade in maize leaves, in which ZmMPK5, a candidate for MAPK, is demonstrated to be involved.

  4. Proteomic Identification of Annexins, Calcium-Dependent Membrane Binding Proteins That Mediate Osmotic Stress and Abscisic Acid Signal Transduction in Arabidopsis

    Science.gov (United States)

    Lee, Sumin; Lee, Eun Jung; Yang, Eun Ju; Lee, Ji Eun; Park, Ae Ran; Song, Won Hyun; Park, Ohkmae K.

    2004-01-01

    Comparative proteomic analysis of the Arabidopsis thaliana root microsomal fraction was performed to identify novel components of salt stress signaling. Among the salt-responsive microsomal proteins, two spots that increased upon salt treatment on a two-dimensional gel were identified as the same protein, designated annexin 1 (AnnAt1). Annexins comprise a multigene family of Ca2+-dependent membrane binding proteins and have been extensively studied in animal cells. AnnAt1 is strongly expressed in root but rarely in flower tissue. In this study, the results suggest that salt stress induces translocation from the cytosol to the membrane and potential turnover of existing protein. This process is blocked by EGTA treatment, implying that AnnAt1 functions in stress response are tightly associated with Ca2+. T-DNA insertion mutants of annAt1 and a different isoform, annAt4, displayed hypersensitivity to osmotic stress and abscisic acid (ABA) during germination and early seedling growth. The results collectively suggest that AnnAt1 and AnnAt4 play important roles in osmotic stress and ABA signaling in a Ca2+-dependent manner. PMID:15161963

  5. Roles of arabidopsis WRKY18, WRKY40 and WRKY60 transcription factors in plant responses to abscisic acid and abiotic stress

    OpenAIRE

    Chen Zhixiang; Xiao Yong; Shi Junwei; Lai Zhibing; Chen Han; Xu Xinping

    2010-01-01

    Abstract Background WRKY transcription factors are involved in plant responses to both biotic and abiotic stresses. Arabidopsis WRKY18, WRKY40, and WRKY60 transcription factors interact both physically and functionally in plant defense responses. However, their role in plant abiotic stress response has not been directly analyzed. Results We report that the three WRKYs are involved in plant responses to abscisic acid (ABA) and abiotic stress. Through analysis of single, double, and triple muta...

  6. Overexpression of an Arabidopsis cysteine-rich receptor-like protein kinase, CRK5, enhances abscisic acid sensitivity and confers drought tolerance

    OpenAIRE

    Lu, Kai; Liang, Shan; Wu, Zhen; Bi, Chao; Yu, Yong-Tao; Wang, Xiao-Fang; Zhang, Da-Peng

    2016-01-01

    Receptor-like kinases (RLKs) have been reported to regulate many developmental and defense process, but only a few members have been functionally characterized. In the present study, our observations suggest that one of the RLKs, a membrane-localized cysteine-rich receptor-like protein kinase, CRK5, is involved in abscisic acid (ABA) signaling in Arabidopsis thaliana. Overexpression of CRK5 increases ABA sensitivity in ABA-induced early seedling growth arrest and promotion of stomatal closure...

  7. Antagonistic roles of abscisic acid and cytokinin during response to nitrogen depletion in oleaginous microalga Nannochloropsis oceanica expand the evolutionary breadth of phytohormone function

    Czech Academy of Sciences Publication Activity Database

    Lu, Y.; Tarkowská, Danuše; Turečková, Veronika; Luo, T.; Xin, Y.; Li, J.; Wang, Q.; Jiao, N.; Strnad, Miroslav; Xu, J.

    2014-01-01

    Roč. 80, č. 1 (2014), s. 52-68 ISSN 0960-7412 R&D Projects: GA ČR GA206/09/1284; GA MŠk LK21306; GA MŠk(CZ) LO1204 Grant - others:GA MŠk(CZ) ED0007/01/01 Program:ED Institutional support: RVO:61389030 Keywords : Nannochloropsis oceanica * antagonistic synergy * abscisic acid Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 5.972, year: 2014

  8. The ratio of red light to far red light alters Arabidopsis axillary bud growth and abscisic acid signalling before stem auxin changes

    OpenAIRE

    Holalu, Srinidhi V.; Finlayson, Scott A.

    2017-01-01

    Abstract Arabidopsis thaliana shoot branching is inhibited by a low red light to far red light ratio (R:FR, an indicator of competition), and by loss of phytochrome B function. Prior studies have shown that phytochrome B deficiency suppresses bud growth by elevating systemic auxin signalling, and that increasing the R:FR promotes the growth of buds suppressed by low R:FR by inhibiting bud abscisic acid (ABA) accumulation and signalling. Here, systemic auxin signalling and bud ABA signalling w...

  9. ASCORBATE PEROXIDASE6 protects Arabidopsis desiccating and germinating seeds from stress and mediates cross talk between reactive oxygen species, abscisic acid, and auxin

    Czech Academy of Sciences Publication Activity Database

    Chen, Ch.; Letnik, I.; Hacham, Y.; Dobrev, Petre; Ben-Daniel, B.H.; Vaňková, Radomíra; Amir, R.; Miller, G.

    2014-01-01

    Roč. 166, č. 1 (2014), s. 370-383 ISSN 0032-0889 R&D Projects: GA ČR GA206/09/2062 Institutional support: RVO:61389030 Keywords : Arabidopsis thaliana * abscisic acid * germinating seeds Subject RIV: ED - Physiology Impact factor: 6.841, year: 2014 http://gateway.isiknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=Alerting&SrcApp=Alerting&DestApp=MEDLINE&DestLinkType=FullRecord&UT=25049361

  10. Crystallization of the plant hormone receptors PYL9/RCAR1, PYL5/RCAR8 and PYR1/RCAR11 in the presence of (+)-abscisic acid

    International Nuclear Information System (INIS)

    Shibata, Nobuyuki; Kagiyama, Megumi; Nakagawa, Masahiro; Hirano, Yoshinori; Hakoshima, Toshio

    2010-01-01

    Crystals of the Arabidopsis abscisic acid receptors PYL9/RCAR1, PYL5/RCAR8 and PYR1/RCAR11 have been obtained. Abscisic acid (ABA) is a plant hormone that plays key regulatory roles in physiological pathways for the adaptation of vegetative tissues to abiotic stresses such as water stress in addition to events pertaining to plant growth and development. The Arabidopsis ABA receptor proteins PYR/PYLs/RCARs form a START family that contains 14 members which are classified into three subfamilies (I–III). Here, purification, crystallization and X-ray data collection are reported for a member of each of the subfamilies, PYL9/RCAR1 from subfamily I, PYL5/RCAR8 from subfamily II and PYR1/RCAR11 from subfamily III, in the presence of (+)-abscisic acid. The three proteins crystallize in space groups P3 1 21/P3 2 21, P2 and P1, respectively. X-ray intensity data were collected to 1.9–2.6 Å resolution

  11. Quantification of abscisic acid in grapevine leaf (Vitis vinifera) by isotope-dilution liquid chromatography-mass spectrometry.

    Science.gov (United States)

    Vilaró, Francisca; Canela-Xandri, Anna; Canela, Ramon

    2006-09-01

    A specific, sensitive, precise, and accurate method for the determination of abscisic acid (ABA) in grapevine leaf tissues is described. The method employs high-performance liquid chromatography and electrospray ionization-mass spectrometry (LC-ESI-MS) in selected ion monitoring mode (SIM) to analyze ABA using a stable isotope-labeled ABA as an internal standard. Absolute recoveries ranged from 72% to 79% using methanol/water pH 5.5 (50:50 v/v) as an extraction solvent. The best efficiency was obtained when the chromatographic separation was carried out by using a porous graphitic carbon (PGC) column. The statistical evaluation of the method was satisfactory in the work range. A relative standard deviation (RDS) of < 5.5% and < 6.0% was obtained for intra-batch and inter-batch comparisons, respectively. As for accuracy, the relative error (%Er) was between -2.7 and 4.3%, and the relative recovery ranged from 95% to 107%.

  12. An Alfin-like gene from Atriplex hortensis enhances salt and drought tolerance and abscisic acid response in transgenic Arabidopsis.

    Science.gov (United States)

    Tao, Jian-Jun; Wei, Wei; Pan, Wen-Jia; Lu, Long; Li, Qing-Tian; Ma, Jin-Biao; Zhang, Wan-Ke; Ma, Biao; Chen, Shou-Yi; Zhang, Jin-Song

    2018-02-09

    Alfin-like (AL) is a small plant-specific gene family with prominent roles in root growth and abiotic stress response. Here, we aimed to identify novel stress tolerance AL genes from the stress-tolerant species Atriplex hortensis. Totally, we isolated four AhAL genes, all encoding nuclear-localized proteins with cis-element-binding and transrepression activities. Constitutive expression of AhAL1 in Arabidopsis facilitated plants to survive under saline condition, while expressing anyone of the other three AhAL genes led to salt-hypersensitive response, indicating functional divergence of AhAL family. AhAL1 also conferred enhanced drought tolerance, as judged from enhanced survival, improved growth, decreased malonaldehyde (MDA) content and reduced water loss in AhAL1-expressing plants compared to WT. In addition, abscisic acid (ABA)-mediated stomatal closure and inhibition of seed germination and primary root elongation were enhanced in AhAL1-transgenic plants. Further analysis demonstrated that AhAL1 could bind to promoter regions of GRF7, DREB1C and several group-A PP2C genes and repress their expression. Correspondingly, the expression levels of positive stress regulator genes DREB1A, DREB2A and three ABFs were all increased in AhAL1-expressing plants. Based on these results, AhAL1 was identified as a novel candidate gene for improving abiotic stress tolerance of crop plants.

  13. Abscisic Acid Signaling and Abiotic Stress Tolerance in Plants: A Review on Current Knowledge and Future Prospects.

    Science.gov (United States)

    Vishwakarma, Kanchan; Upadhyay, Neha; Kumar, Nitin; Yadav, Gaurav; Singh, Jaspreet; Mishra, Rohit K; Kumar, Vivek; Verma, Rishi; Upadhyay, R G; Pandey, Mayank; Sharma, Shivesh

    2017-01-01

    Abiotic stress is one of the severe stresses of environment that lowers the growth and yield of any crop even on irrigated land throughout the world. A major phytohormone abscisic acid (ABA) plays an essential part in acting toward varied range of stresses like heavy metal stress, drought, thermal or heat stress, high level of salinity, low temperature, and radiation stress. Its role is also elaborated in various developmental processes including seed germination, seed dormancy, and closure of stomata. ABA acts by modifying the expression level of gene and subsequent analysis of cis - and trans -acting regulatory elements of responsive promoters. It also interacts with the signaling molecules of processes involved in stress response and development of seeds. On the whole, the stress to a plant can be susceptible or tolerant by taking into account the coordinated activities of various stress-responsive genes. Numbers of transcription factor are involved in regulating the expression of ABA responsive genes by acting together with their respective cis -acting elements. Hence, for improvement in stress-tolerance capacity of plants, it is necessary to understand the mechanism behind it. On this ground, this article enlightens the importance and role of ABA signaling with regard to various stresses as well as regulation of ABA biosynthetic pathway along with the transcription factors for stress tolerance.

  14. The Interrelationship between Abscisic Acid and Reactive Oxygen Species Plays a Key Role in Barley Seed Dormancy and Germination.

    Science.gov (United States)

    Ishibashi, Yushi; Aoki, Nozomi; Kasa, Shinsuke; Sakamoto, Masatsugu; Kai, Kyohei; Tomokiyo, Reisa; Watabe, Gaku; Yuasa, Takashi; Iwaya-Inoue, Mari

    2017-01-01

    Seed dormancy is one of the adaptive responses in the plant life cycle and an important agronomic trait. Reactive oxygen species (ROS) release seed dormancy and promote seed germination in several cereal crops; however, the key regulatory mechanism of ROS-mediated seed dormancy and germination remains controversial. Here, we focused on the relationship between hydrogen peroxide (a ROS) and abscisic acid (ABA) in dormant and non-dormant barley seeds. The hydrogen peroxide (H 2 O 2 ) level produced in barley seed embryos after imbibition was higher in non-dormant seeds than in dormant seeds. H 2 O 2 regulated the ABA content in the embryos through ABA-8'-hydroxylase, an ABA catabolic enzyme. Moreover, compared with non-dormant seeds, in dormant seeds the activity of NADPH oxidase, which produces ROS, was lower, whereas the activity of catalase, which is a H 2 O 2 scavenging enzyme, was higher, as was the expression of HvCAT2 . Furthermore, precocious germination of isolated immature embryos was suppressed by the transient introduction of HvCAT2 driven by the maize ( Zea mays ) ubiquitin promoter. HvCAT2 expression was regulated through an ABA-responsive transcription factor (HvABI5) induced by ABA. These results suggest that the changing of balance between ABA and ROS is active in barley seed embryos after imbibition and regulates barley seed dormancy and germination.

  15. Overexpression of Pyrabactin Resistance-Like Abscisic Acid Receptors Enhances Drought, Osmotic, and Cold Tolerance in Transgenic Poplars

    Directory of Open Access Journals (Sweden)

    Jingling Yu

    2017-10-01

    Full Text Available Abscisic acid (ABA has been known participate in a wider range of adaptive responses to diverse environmental abiotic stresses such as drought, osmosis, and low temperatures. ABA signaling is initiated by its receptors PYR/PYL/RCARs, a type of soluble proteins with a conserved START domain which can bind ABA and trigger the downstream pathway. Previously, we discovered that poplar (Populus trichocarpa genome encodes 14 PYR/PYL/RCAR orthologs (PtPYRLs, and two of them, PtPYRL1 and PtPYRL5 have been functionally characterized to positively regulate drought tolerance. However, the physiological function of these ABA receptors in poplar remains uncharacterized. Here, we generated transgenic poplar plants overexpressing PtPYRL1 and PtPYRL5 and found that they exhibited more vigorous growth and produced greater biomass when exposed to drought stress. The improved drought tolerance was positively correlated with the key physiological responses dictated by the ABA signaling pathway, including increase in stomatal closure and decrease in leaf water loss. Further analyses revealed that overexpression lines showed improved capacity in scavenging reactive oxygen species and enhanced the activation of antioxidant enzymes under drought stress. Moreover, overexpression of PtPYRL1 or PtPYRL5 significantly increased the poplar resistance to osmotic and cold stresses. In summary, our results suggest that constitutive expression of PtPYRL1 and PtPYRL5 significantly enhances the resistance to drought, osmotic and cold stresses by positively regulating ABA signaling in poplar.

  16. Abscisic acid deficiency causes changes in cuticle permeability and pectin composition that influence tomato resistance to Botrytis cinerea.

    Science.gov (United States)

    Curvers, Katrien; Seifi, Hamed; Mouille, Grégory; de Rycke, Riet; Asselbergh, Bob; Van Hecke, Annelies; Vanderschaeghe, Dieter; Höfte, Herman; Callewaert, Nico; Van Breusegem, Frank; Höfte, Monica

    2010-10-01

    A mutant of tomato (Solanum lycopersicum) with reduced abscisic acid (ABA) production (sitiens) exhibits increased resistance to the necrotrophic fungus Botrytis cinerea. This resistance is correlated with a rapid and strong hydrogen peroxide-driven cell wall fortification response in epidermis cells that is absent in tomato with normal ABA production. Moreover, basal expression of defense genes is higher in the mutant compared with the wild-type tomato. Given the importance of this fast response in sitiens resistance, we investigated cell wall and cuticle properties of the mutant at the chemical, histological, and ultrastructural levels. We demonstrate that ABA deficiency in the mutant leads to increased cuticle permeability, which is positively correlated with disease resistance. Furthermore, perturbation of ABA levels affects pectin composition. sitiens plants have a relatively higher degree of pectin methylesterification and release different oligosaccharides upon inoculation with B. cinerea. These results show that endogenous plant ABA levels affect the composition of the tomato cuticle and cell wall and demonstrate the importance of cuticle and cell wall chemistry in shaping the outcome of this plant-fungus interaction.

  17. Ethylene responses in rice roots and coleoptiles are differentially regulated by a carotenoid isomerase-mediated abscisic acid pathway.

    Science.gov (United States)

    Yin, Cui-Cui; Ma, Biao; Collinge, Derek Phillip; Pogson, Barry James; He, Si-Jie; Xiong, Qing; Duan, Kai-Xuan; Chen, Hui; Yang, Chao; Lu, Xiang; Wang, Yi-Qin; Zhang, Wan-Ke; Chu, Cheng-Cai; Sun, Xiao-Hong; Fang, Shuang; Chu, Jin-Fang; Lu, Tie-Gang; Chen, Shou-Yi; Zhang, Jin-Song

    2015-04-01

    Ethylene and abscisic acid (ABA) act synergistically or antagonistically to regulate plant growth and development. ABA is derived from the carotenoid biosynthesis pathway. Here, we analyzed the interplay among ethylene, carotenoid biogenesis, and ABA in rice (Oryza sativa) using the rice ethylene response mutant mhz5, which displays a reduced ethylene response in roots but an enhanced ethylene response in coleoptiles. We found that MHZ5 encodes a carotenoid isomerase and that the mutation in mhz5 blocks carotenoid biosynthesis, reduces ABA accumulation, and promotes ethylene production in etiolated seedlings. ABA can largely rescue the ethylene response of the mhz5 mutant. Ethylene induces MHZ5 expression, the production of neoxanthin, an ABA biosynthesis precursor, and ABA accumulation in roots. MHZ5 overexpression results in enhanced ethylene sensitivity in roots and reduced ethylene sensitivity in coleoptiles. Mutation or overexpression of MHZ5 also alters the expression of ethylene-responsive genes. Genetic studies revealed that the MHZ5-mediated ABA pathway acts downstream of ethylene signaling to inhibit root growth. The MHZ5-mediated ABA pathway likely acts upstream but negatively regulates ethylene signaling to control coleoptile growth. Our study reveals novel interactions among ethylene, carotenogenesis, and ABA and provides insight into improvements in agronomic traits and adaptive growth through the manipulation of these pathways in rice. © 2015 American Society of Plant Biologists. All rights reserved.

  18. Meristem maintenance, auxin, jasmonic and abscisic acid pathways as a mechanism for phenotypic plasticity in Antirrhinum majus

    Science.gov (United States)

    Weiss, Julia; Alcantud-Rodriguez, Raquel; Toksöz, Tugba; Egea-Cortines, Marcos

    2016-01-01

    Plants grow under climatic changing conditions that cause modifications in vegetative and reproductive development. The degree of changes in organ development i.e. its phenotypic plasticity seems to be determined by the organ identity and the type of environmental cue. We used intraspecific competition and found that Antirrhinum majus behaves as a decoupled species for lateral organ size and number. Crowding causes decreases in leaf size and increased leaf number whereas floral size is robust and floral number is reduced. Genes involved in shoot apical meristem maintenance like ROA and HIRZ, cell cycle (CYCD3a; CYCD3b, HISTONE H4) or organ polarity (GRAM) were not significantly downregulated under crowding conditions. A transcriptomic analysis of inflorescence meristems showed Gene Ontology enriched pathways upregulated including Jasmonic and Abscisic acid synthesis and or signalling. Genes involved in auxin synthesis such as AmTAR2 and signalling AmANT were not affected by crowding. In contrast, AmJAZ1, AmMYB21, AmOPCL1 and AmABA2 were significantly upregulated. Our work provides a mechanistic working hypothesis where a robust SAM and stable auxin signalling enables a homogeneous floral size while changes in JA and ABA signalling maybe responsible for the decreased leaf size and floral number.

  19. Dehydration stress-induced oscillations in LEA protein transcripts involves abscisic acid in the moss, Physcomitrella patens.

    Science.gov (United States)

    Shinde, Suhas; Nurul Islam, M; Ng, Carl K-Y

    2012-07-01

    • Physcomitrella patens is a bryophyte belonging to early diverging lineages of land plants following colonization of land in the Ordovician period. Mosses are typically found in refugial habitats and can experience rapidly fluctuating environmental conditions. The acquisition of dehydration tolerance by bryophytes is of fundamental importance as they lack water-conducting tissues and are generally one cell layer thick. • Here, we show that dehydration induced oscillations in the steady-state transcript abundances of two group 3 late embryogenesis abundant (LEA) protein genes in P. patens protonemata, and that the amplitudes of these oscillations are reflective of the severity of dehydration stress. • Dehydration stress also induced elevations in the concentrations of abscisic acid (ABA), and ABA alone can also induce dosage-dependent oscillatory increases in the steady-state abundance of LEA protein transcripts. Additionally, removal of ABA resulted in rapid attenuation of these oscillatory increases. • Our data demonstrate that dehydration stress-regulated expression of LEA protein genes is temporally dynamic and highlight the importance of oscillations as a robust mechanism for optimal responses. Our results suggest that dehydration stress-induced oscillations in the steady-state abundance of LEA protein transcripts may constitute an important cellular strategy for adaptation to life in a constantly changing environment. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

  20. Epoxycarotenoid-mediated synthesis of abscisic acid in Physcomitrella patens implicating conserved mechanisms for acclimation to hyperosmosis in embryophytes.

    Science.gov (United States)

    Takezawa, Daisuke; Watanabe, Naoki; Ghosh, Totan Kumar; Saruhashi, Masashi; Suzuki, Atsushi; Ishiyama, Kanako; Somemiya, Shinnosuke; Kobayashi, Masatomo; Sakata, Yoichi

    2015-04-01

    Plants acclimate to environmental stress signals such as cold, drought and hypersalinity, and provoke internal protective mechanisms. Abscisic acid (ABA), a carotenoid-derived phytohormone, which increases in response to the stress signals above, has been suggested to play a key role in the acclimation process in angiosperms, but the role of ABA in basal land plants such as mosses, including its biosynthetic pathways, has not been clarified. Targeted gene disruption of PpABA1, encoding zeaxanthin epoxidase in the moss Physcomitrella patens was conducted to determine the role of endogenous ABA in acclimation processes in mosses. The generated ppaba1 plants were found to accumulate only a small amount of endogenous ABA. The ppaba1 plants showed reduced osmotic acclimation capacity in correlation with reduced dehydration tolerance and accumulation of late embryogenesis abundant proteins. By contrast, cold-induced freezing tolerance was less affected in ppaba1, indicating that endogenous ABA does not play a major role in the regulation of cold acclimation in the moss. Our results suggest that the mechanisms for osmotic acclimation mediated by carotenoid-derived synthesis of ABA are conserved in embryophytes and that acquisition of the mechanisms played a crucial role in terrestrial adaptation and colonization by land plant ancestors. © 2014 The Authors New Phytologist © 2014 New Phytologist Trust.

  1. Gene Overexpression and RNA Silencing Tools for the Genetic Manipulation of the S-(+)-Abscisic Acid Producing Ascomycete Botrytis cinerea.

    Science.gov (United States)

    Ding, Zhong-Tao; Zhang, Zhi; Luo, Di; Zhou, Jin-Yan; Zhong, Juan; Yang, Jie; Xiao, Liang; Shu, Dan; Tan, Hong

    2015-05-06

    The phytopathogenic ascomycete Botrytis cinerea produces several secondary metabolites that have biotechnical significance and has been particularly used for S-(+)-abscisic acid production at the industrial scale. To manipulate the expression levels of specific secondary metabolite biosynthetic genes of B. cinerea with Agrobacterium tumefaciens-mediated transformation system, two expression vectors (pCBh1 and pCBg1 with different selection markers) and one RNA silencing vector, pCBSilent1, were developed with the In-Fusion assembly method. Both expression vectors were highly effective in constitutively expressing eGFP, and pCBSilent1 effectively silenced the eGFP gene in B. cinerea. Bcaba4, a gene suggested to participate in ABA biosynthesis in B. cinerea, was then targeted for gene overexpression and RNA silencing with these reverse genetic tools. The overexpression of bcaba4 dramatically induced ABA formation in the B. cinerea wild type strain Bc-6, and the gene silencing of bcaba4 significantly reduced ABA-production in an ABA-producing B. cinerea strain.

  2. Graviresponsiveness and abscisic-acid content of roots of carotenoid-deficient mutants of Zea mays L

    Science.gov (United States)

    Moore, R.; Smith, J. D.

    1985-01-01

    The abscisic-acid (ABA) content of roots of the carotenoid-deficient w-3, vp-5, and vp-7 mutants of Z. mays was analyzed using gas chromatography-mass spectrometry with an analysis sensitivity of 6 ng ABA g-1 fresh weight (FW). Roots of normal seedlings of the same lines were characterized by the following amounts of ABA (as ng ABA g-1 FW, +/- standard deviation): w-3, 279 +/- 43; vp-5, 237 +/- 26; vp-7, 338 +/- 61. We did not detect any ABA in roots of any of the mutants. Thus, the lack of carotenoids in these mutants correlated positively with the apparent absence of ABA. Primary roots of normal and mutant seedlings were positively gravitropic, with no significant differences in the curvatures of roots of normal as compared with mutant seedlings. These results indicate that ABA 1) is synthesized in maize roots via the carotenoid pathway, and 2) is not necessary for positive gravitropism by primary roots of Z. mays.

  3. LANCL2 is necessary for abscisic acid binding and signaling in human granulocytes and in rat insulinoma cells.

    Science.gov (United States)

    Sturla, Laura; Fresia, Chiara; Guida, Lucrezia; Bruzzone, Santina; Scarfì, Sonia; Usai, Cesare; Fruscione, Floriana; Magnone, Mirko; Millo, Enrico; Basile, Giovanna; Grozio, Alessia; Jacchetti, Emanuela; Allegretti, Marcello; De Flora, Antonio; Zocchi, Elena

    2009-10-09

    Abscisic acid (ABA) is a plant hormone regulating fundamental physiological functions in plants, such as response to abiotic stress. Recently, ABA was shown to be produced and released by human granulocytes, by insulin-producing rat insulinoma cells, and by human and murine pancreatic beta cells. ABA autocrinally stimulates the functional activities specific for each cell type through a receptor-operated signal transduction pathway, sequentially involving a pertussis toxin-sensitive receptor/G-protein complex, cAMP, CD38-produced cADP-ribose and intracellular calcium. Here we show that the lanthionine synthetase C-like protein LANCL2 is required for ABA binding on the membrane of human granulocytes and that LANCL2 is necessary for transduction of the ABA signal into the cell-specific functional responses in granulocytes and in rat insulinoma cells. Co-expression of LANCL2 and CD38 in the human HeLa cell line reproduces the ABA-signaling pathway. Results obtained with granulocytes and CD38(+)/LANCL2(+) HeLa transfected with a chimeric G-protein (G alpha(q/i)) suggest that the pertussis toxin-sensitive G-protein coupled to LANCL2 is a G(i). Identification of LANCL2 as a critical component of the ABA-sensing protein complex will enable the screening of synthetic ABA antagonists as prospective new anti-inflammatory and anti-diabetic agents.

  4. Microgram amounts of abscisic acid in fruit extracts improve glucose tolerance and reduce insulinemia in rats and in humans.

    Science.gov (United States)

    Magnone, Mirko; Ameri, Pietro; Salis, Annalisa; Andraghetti, Gabriella; Emionite, Laura; Murialdo, Giovanni; De Flora, Antonio; Zocchi, Elena

    2015-12-01

    2-Cis,4-trans-abscisic acid (ABA) is a plant hormone that is present also in animals. Several lines of evidence suggest that ABA contributes to the regulation of glycemia in mammals: nanomolar ABA stimulates insulin release from β-pancreatic cells and glucose transporter-4-mediated glucose uptake by myoblasts and adipocytes in vitro; plasma ABA increases in normal human subjects, but not in diabetic patients, after a glucose load for an oral glucose tolerance test (OGTT). The presence of ABA in fruits prompted an exploration of the bioavailability of dietary ABA and the effect of ABA-rich fruit extracts on glucose tolerance. Rats underwent an OGTT, with or without 1 µg/kg ABA, either synthetic or present in a fruit extract. Human volunteers underwent an OGTT or a standard breakfast and lunch, with or without a fruit extract, yielding an ABA dose of 0.85 or 0.5 µg/kg, respectively. Plasma glucose, insulin, and ABA were measured at different time points. Oral ABA at 0.5-1 µg/kg significantly lowered glycemia and insulinemia in rats and in humans. Thus, the glycemia-lowering effect of low-dose ABA in vivo does not depend on an increased insulin release. Low-dose ABA intake may be proposed as an aid to improving glucose tolerance in patients with diabetes who are deficient in or resistant to insulin. © FASEB.

  5. The plant hormone abscisic acid stimulates the proliferation of human hemopoietic progenitors through the second messenger cyclic ADP-ribose.

    Science.gov (United States)

    Scarfì, Sonia; Fresia, Chiara; Ferraris, Chiara; Bruzzone, Santina; Fruscione, Floriana; Usai, Cesare; Benvenuto, Federica; Magnone, Mirko; Podestà, Marina; Sturla, Laura; Guida, Lucrezia; Albanesi, Ennio; Damonte, Gianluca; Salis, Annalisa; De Flora, Antonio; Zocchi, Elena

    2009-10-01

    Abscisic acid (ABA) is a hormone involved in pivotal physiological functions in higher plants, such as response to abiotic stress and control of seed dormancy and germination. Recently, ABA was demonstrated to be autocrinally produced by human granulocytes, beta pancreatic cells, and mesenchymal stem cells (MSC) and to stimulate cell-specific functions through a signaling pathway involving the second messenger cyclic ADP-ribose (cADPR). Here we show that ABA expands human uncommitted hemopoietic progenitors (HP) in vitro, through a cADPR-mediated increase of the intracellular calcium concentration ([Ca(2+)](i)). Incubation of CD34(+) cells with micromolar ABA also induces transcriptional effects, which include NF-kappaB nuclear translocation and transcription of genes encoding for several cytokines. Human MSC stimulated with a lymphocyte-conditioned medium produce and release ABA at concentrations sufficient to exert growth-stimulatory effects on co-cultured CD34(+) cells, as demonstrated by the inhibition of colony growth in the presence of an anti-ABA monoclonal antibody. These results provide a remarkable example of conservation of a stress hormone and of its second messenger from plants to humans and identify ABA as a new hemopoietic growth factor involved in the cross-talk between HP and MSC.

  6. Abscisic acid is an endogenous stimulator of insulin release from human pancreatic islets with cyclic ADP ribose as second messenger.

    Science.gov (United States)

    Bruzzone, Santina; Bodrato, Nicoletta; Usai, Cesare; Guida, Lucrezia; Moreschi, Iliana; Nano, Rita; Antonioli, Barbara; Fruscione, Floriana; Magnone, Mirko; Scarfì, Sonia; De Flora, Antonio; Zocchi, Elena

    2008-11-21

    Abscisic acid (ABA) is a plant stress hormone recently identified as an endogenous pro-inflammatory cytokine in human granulocytes. Because paracrine signaling between pancreatic beta cells and inflammatory cells is increasingly recognized as a pathogenetic mechanism in the metabolic syndrome and type II diabetes, we investigated the effect of ABA on insulin secretion. Nanomolar ABA increases glucose-stimulated insulin secretion from RIN-m and INS-1 cells and from murine and human pancreatic islets. The signaling cascade triggered by ABA in insulin-releasing cells sequentially involves a pertussis toxin-sensitive G protein, cAMP overproduction, protein kinase A-mediated activation of the ADP-ribosyl cyclase CD38, and cyclic ADP-ribose overproduction. ABA is rapidly produced and released from human islets, RIN-m, and INS-1 cells stimulated with high glucose concentrations. In conclusion, ABA is an endogenous stimulator of insulin secretion in human and murine pancreatic beta cells. Autocrine release of ABA by glucose-stimulated pancreatic beta cells, and the paracrine production of the hormone by activated granulocytes and monocytes suggest that ABA may be involved in the physiology of insulin release as well as in its dysregulation under conditions of inflammation.

  7. Abscisic acid released by human monocytes activates monocytes and vascular smooth muscle cell responses involved in atherogenesis.

    Science.gov (United States)

    Magnone, Mirko; Bruzzone, Santina; Guida, Lucrezia; Damonte, Gianluca; Millo, Enrico; Scarfì, Sonia; Usai, Cesare; Sturla, Laura; Palombo, Domenico; De Flora, Antonio; Zocchi, Elena

    2009-06-26

    Abscisic acid (ABA) is a phytohormone recently identified as a new endogenous pro-inflammatory hormone in human granulocytes. Here we report the functional activation of human monocytes and vascular smooth muscle cells by ABA. Incubation of monocytes with ABA evokes an intracellular Ca2+ rise through the second messenger cyclic ADP-ribose, leading to NF-kappaB activation and consequent increase of cyclooxygenase-2 expression and prostaglandin E2 production and enhanced release of MCP-1 (monocyte chemoattractant protein-1) and of metalloprotease-9, all events reportedly involved in atherogenesis. Moreover, monocytes release ABA when exposed to thrombin-activated platelets, a condition occurring at the injured vascular endothelium; monocyte-derived ABA behaves as an autocrine and paracrine pro-inflammatory hormone-stimulating monocyte migration and MCP-1 release, as well as vascular smooth muscle cells migration and proliferation. These results, and the presence of ABA in human arterial plaques at a 10-fold higher concentration compared with normal arterial tissue, identify ABA as a new signal molecule involved in the development of atherosclerosis and suggest a possible new target for anti-atherosclerotic therapy.

  8. Abscisic Acid Released by Human Monocytes Activates Monocytes and Vascular Smooth Muscle Cell Responses Involved in Atherogenesis*

    Science.gov (United States)

    Magnone, Mirko; Bruzzone, Santina; Guida, Lucrezia; Damonte, Gianluca; Millo, Enrico; Scarfì, Sonia; Usai, Cesare; Sturla, Laura; Palombo, Domenico; De Flora, Antonio; Zocchi, Elena

    2009-01-01

    Abscisic acid (ABA) is a phytohormone recently identified as a new endogenous pro-inflammatory hormone in human granulocytes. Here we report the functional activation of human monocytes and vascular smooth muscle cells by ABA. Incubation of monocytes with ABA evokes an intracellular Ca2+ rise through the second messenger cyclic ADP-ribose, leading to NF-κB activation and consequent increase of cyclooxygenase-2 expression and prostaglandin E2 production and enhanced release of MCP-1 (monocyte chemoattractant protein-1) and of metalloprotease-9, all events reportedly involved in atherogenesis. Moreover, monocytes release ABA when exposed to thrombin-activated platelets, a condition occurring at the injured vascular endothelium; monocyte-derived ABA behaves as an autocrine and paracrine pro-inflammatory hormone-stimulating monocyte migration and MCP-1 release, as well as vascular smooth muscle cells migration and proliferation. These results, and the presence of ABA in human arterial plaques at a 10-fold higher concentration compared with normal arterial tissue, identify ABA as a new signal molecule involved in the development of atherosclerosis and suggest a possible new target for anti-atherosclerotic therapy. PMID:19332545

  9. The plant hormone abscisic acid increases in human plasma after hyperglycemia and stimulates glucose consumption by adipocytes and myoblasts.

    Science.gov (United States)

    Bruzzone, Santina; Ameri, Pietro; Briatore, Lucia; Mannino, Elena; Basile, Giovanna; Andraghetti, Gabriella; Grozio, Alessia; Magnone, Mirko; Guida, Lucrezia; Scarfì, Sonia; Salis, Annalisa; Damonte, Gianluca; Sturla, Laura; Nencioni, Alessio; Fenoglio, Daniela; Fiory, Francesca; Miele, Claudia; Beguinot, Francesco; Ruvolo, Vittorio; Bormioli, Mariano; Colombo, Giuseppe; Maggi, Davide; Murialdo, Giovanni; Cordera, Renzo; De Flora, Antonio; Zocchi, Elena

    2012-03-01

    The plant hormone abscisic acid (ABA) is released from glucose-challenged human pancreatic β cells and stimulates insulin secretion. We investigated whether plasma ABA increased during oral and intravenous glucose tolerance tests (OGTTs and IVGTTs) in healthy human subjects. In all subjects undergoing OGTTs (n=8), plasma ABA increased over basal values (in a range from 2- to 9-fold). A positive correlation was found between the ABA area under the curve (AUC) and the glucose AUC. In 4 out of 6 IVGTTs, little or no increase of ABA levels was observed. In the remaining subjects, the ABA increase was similar to that recorded during OGTTs. GLP-1 stimulated ABA release from an insulinoma cell line and from human islets, by ∼10- and 2-fold in low and high glucose, respectively. Human adipose tissue also released ABA in response to high glucose. Nanomolar ABA stimulated glucose uptake, similarly to insulin, in rat L6 myoblasts and in murine 3T3-L1 cells differentiated to adipocytes, by increasing GLUT-4 translocation to the plasma membrane. Demonstration that a glucose load in humans is followed by a physiological rise of plasma ABA, which can enhance glucose uptake by adipose tissues and muscle cells, identifies ABA as a new mammalian hormone involved in glucose metabolism.

  10. Genetic interaction of two abscisic acid signaling regulators, HY5 and FIERY1, in mediating lateral root formation

    KAUST Repository

    Chen, Hao

    2011-01-01

    Root architecture is continuously shaped in a manner that helps plants to better adapt to the environment. Gene regulation at the transcriptional or post-transcriptional levels largely controls this environmental response. Recently, RNA silencing has emerged as an important player in gene regulation and is involved in many aspects of plant development, including lateral root formation. In a recent study, we found that FIERY1, a bifunctional abiotic stress and abscisic acid (ABA) signaling regulator and an endogenous RNA silencing suppressor, mediates auxin response during lateral root formation in Arabidopsis. We proposed that FRY1 regulates lateral root development through its activity on adenosine 3,5-bisphosphate (PAP), a strong inhibitor of exoribonucleases (XRNs). Interestingly, some of the phenotypes of fry1, such as enhanced response to light in repressing hypocotyl elongation and hypersensitivity to ABA in lateral root growth, are opposite to those of another light- and ABA-signaling mutant, hy5. Here we analyzed the hy5 fry1 double mutant for root and hypocotyl growth. We found that the hy5 mutation can suppress the enhanced light sensitivity in fry1 hypocotyl elongation and restore the lateral root formation. The genetic interaction between HY5 and FRY1 indicates that HY5 and FRY1 may act in overlapping pathways that mediate light signaling and lateral root development. © 2011 Landes Bioscience.

  11. The Interrelationship between Abscisic Acid and Reactive Oxygen Species Plays a Key Role in Barley Seed Dormancy and Germination

    Science.gov (United States)

    Ishibashi, Yushi; Aoki, Nozomi; Kasa, Shinsuke; Sakamoto, Masatsugu; Kai, Kyohei; Tomokiyo, Reisa; Watabe, Gaku; Yuasa, Takashi; Iwaya-Inoue, Mari

    2017-01-01

    Seed dormancy is one of the adaptive responses in the plant life cycle and an important agronomic trait. Reactive oxygen species (ROS) release seed dormancy and promote seed germination in several cereal crops; however, the key regulatory mechanism of ROS-mediated seed dormancy and germination remains controversial. Here, we focused on the relationship between hydrogen peroxide (a ROS) and abscisic acid (ABA) in dormant and non-dormant barley seeds. The hydrogen peroxide (H2O2) level produced in barley seed embryos after imbibition was higher in non-dormant seeds than in dormant seeds. H2O2 regulated the ABA content in the embryos through ABA-8′-hydroxylase, an ABA catabolic enzyme. Moreover, compared with non-dormant seeds, in dormant seeds the activity of NADPH oxidase, which produces ROS, was lower, whereas the activity of catalase, which is a H2O2 scavenging enzyme, was higher, as was the expression of HvCAT2. Furthermore, precocious germination of isolated immature embryos was suppressed by the transient introduction of HvCAT2 driven by the maize (Zea mays) ubiquitin promoter. HvCAT2 expression was regulated through an ABA-responsive transcription factor (HvABI5) induced by ABA. These results suggest that the changing of balance between ABA and ROS is active in barley seed embryos after imbibition and regulates barley seed dormancy and germination. PMID:28377774

  12. Gibberellins and Seed Development in Maize. I. Evidence That Gibberellin/Abscisic Acid Balance Governs Germination versus Maturation Pathways1

    Science.gov (United States)

    White, Constance N.; Proebsting, William M.; Hedden, Peter; Rivin, Carol J.

    2000-01-01

    Abscisic acid (ABA) is required for the regulation of seed maturation in maize (Zea mays L.). Mutants blocked in ABA synthesis (such as viviparous-5) do not mature to quiescent, desiccation-tolerant seeds, but germinate on the ear midway through kernel development. Because gibberellins (GA) and ABA act antagonistically in many aspects of plant development, we hypothesized that ABA antagonizes a positive GA signal for precocious germination in maize. In these experiments, we show that a GA deficiency early in seed development, induced genetically or via biosynthesis inhibitors, suppresses vivipary in ABA-deficient developing kernels. The resulting seeds have both desiccation tolerance and storage longevity. Temporal analysis of GA accumulation in wild-type kernels revealed the accumulation of bioactive GA1 and GA3 prior to the peak in ABA content. We speculate that these GAs stimulate a developmental program leading to vivipary in the absence of normal amounts of ABA, and that a reduction of GA content re-establishes an ABA/GA ratio appropriate for suppression of germination and induction of maturation. In contrast, the induction of a GA deficiency did not suppress vivipary in viviparous-1 mutant kernels, suggesting that VP1 acts downstream of both GA and ABA in programming seed development. PMID:10759503

  13. Hydrogen peroxide mediates abscisic acid-induced HSP70 accumulation and heat tolerance in grafted cucumber plants.

    Science.gov (United States)

    Li, Hao; Liu, Shan-Shan; Yi, Chang-Yu; Wang, Feng; Zhou, Jie; Xia, Xiao-Jian; Shi, Kai; Zhou, Yan-Hong; Yu, Jing-Quan

    2014-12-01

    Root-shoot communications play important roles in plant stress responses. Here, we examined the roles of root-sourced signals in the shoot response to heat in cucumber plants. Cucumber plants grafted onto their own roots and luffa roots were exposed to aerial and root-zone heat to examine their tolerance by assessing the levels of oxidative stress, PSII photoinhibition, accumulation of abscisic acid (ABA), H2 O2 and heat shock protein (HSP) 70 using immunoblotting, chlorophyll fluorescence, immunoassay, CeCl3 staining and Western blotting, respectively. Grafting onto the luffa rootstock enhanced the shoot tolerance to the heat. This enhanced tolerance was associated with increased accumulation of ABA and apoplastic H2 O2 , RBOH transcripts and HSP70 expression and a decrease in oxidative stress in the shoots. The increases in the ABA and H2 O2 concentrations in the shoots were attributed to an increase in ABA transport from roots and an increase in ABA biosynthesis in the shoots when the root-zone and shoots were heat stressed, respectively. Inhibition of H2 O2 accumulation compromised luffa rootstock-induced HSP70 expression and heat tolerance. These results suggest that, under heat stress, ABA triggers the expression of HSP70 in an apoplastic H2 O2 -dependent manner, implicating the role of an ABA-dependent H2 O2 -driven mechanism in a systemic response involving root-shoot communication. © 2014 John Wiley & Sons Ltd.

  14. Eucalyptus ESTs involved in the production of 9-cis epoxycarotenoid dioxygenase, a regulatory enzyme of abscisic acid production

    Directory of Open Access Journals (Sweden)

    Iraê A. Guerrini

    2005-01-01

    Full Text Available Abscisic acid (ABA regulates stress responses in plants, and genomic tools can help us to understand the mechanisms involved in that process. FAPESP, a Brazilian research foundation, in association with four private forestry companies, has established the FORESTs database (https://forests.esalq.usp.br. A search was carried out in the Eucalyptus expressed sequence tag database to find ESTs involved with 9-cis epoxycarotenoid dioxygenase (NCED, the regulatory enzyme for ABA biosynthesis, using the basic local BLAST alignment tool. We found four clusters (EGEZLV2206B11.g, EGJMWD2252H08.g, EGBFRT3107F10.g, and EGEQFB1200H10.g, which represent similar sequences of the gene that produces NCED. Data showed that the EGBFRT3107F10.g cluster was similar to the maize (Zea mays NCED enzyme, while EGEZLV2206B11.g and EGJMWD2252H08.g clusters were similar to the avocado (Persea americana NCED enzyme. All Eucalyptus clusters were expressed in several tissues, especially in flower buds, where ABA has a special participation during the floral development process.

  15. Evidence for a universal pathway of abscisic acid biosynthesis in higher plants from sup 18 O incorporation patterns

    Energy Technology Data Exchange (ETDEWEB)

    Zeevaart, J.A.D.; Heath, T.G.; Gage, D.A. (Michigan State University, East Lansing (USA))

    1989-12-01

    Previous labeling studies of abscisic acid (ABA) with {sup 18}O{sub 2} have been mainly conducted with water-stressed leaves. In this study, {sup 18}O incorporation into ABA of stressed leaves of various species was compared with {sup 18}O labeling of ABA of turgid leaves and of fruit tissue in different stages of ripening. In stressed leaves of all six species investigated, avocado (Persea americana), barley (Hordeum vulgare), bean (Phaseolus vulgaris), cocklebur (Xanthium strumarium), spinach (Spinacia oleracea), and tobacco (Nicotiana tabacum), {sup 18}O was most abundant in the carboxyl group, whereas incorporation of a second and third {sup 18}O in the oxygen atoms on the ring of ABA was much less prominent after 24 h in {sup 18}O{sub 2}. ABA from turgid bean leaves showed significant {sup 18}O incorporation, again with highest {sup 18}O enrichment in the carboxyl group. On the basis of {sup 18}O-labeling patterns observed in ABA from different tissues it is concluded that, despite variations in precusor pool sizes and intermediate turnover rates, there is a universal pathway of ABA biosynthesis in higher plants which involves cleavage of a larger precursor molecule, presumably an oxygenated carotenoid.

  16. Malbec grape (Vitis vinifera L.) responses to the environment: Berry phenolics as influenced by solar UV-B, water deficit and sprayed abscisic acid.

    Science.gov (United States)

    Alonso, Rodrigo; Berli, Federico J; Fontana, Ariel; Piccoli, Patricia; Bottini, Rubén

    2016-12-01

    High-altitude vineyards receive elevated solar ultraviolet-B (UV-B) levels so producing high quality berries for winemaking because of induction in the synthesis of phenolic compounds. Water deficit (D) after veraison, is a commonly used tool to regulate berry polyphenols concentration in red wine cultivars. Abscisic acid (ABA) plays a crucial role in the acclimation to environmental factors/signals (including UV-B and D). The aim of the present study was to evaluate independent and interactive effects of high-altitude solar UV-B, moderate water deficit and ABA applications on Vitis vinifera cv. Malbec berries. The experiment was conducted during two growing seasons with two treatments of UV-B (+UV-B and -UV-B), watering (+D and -D) and ABA (+ABA and -ABA), in a factorial design. Berry fresh weight, sugar content, fruit yield, phenolic compounds profile and antioxidant capacity (ORAC) were analyzed at harvest. Previous incidence of high UV-B prevented deleterious effects of water deficit, i.e. berry weight reduction and diminution of sugar accumulation. High UV-B increased total phenols (mainly astilbin, quercetin and kaempferol) and ORAC, irrespectively of the combination with other factors. Fruit yield was reduced by combining water deficit and high UV-B or water deficit and ABA. Two applications of ABA were enough to induced biochemical changes increasing total anthocyanins, especially those with higher antioxidant capacity. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  17. Exogenous Abscisic Acid Promotes Anthocyanin Biosynthesis and Increased Expression of Flavonoid Synthesis Genes in Vitis vinifera × Vitis labrusca Table Grapes in a Subtropical Region

    Directory of Open Access Journals (Sweden)

    Renata Koyama

    2018-03-01

    Full Text Available Hybrid (Vitis vinifera ×Vitis labrusca table grape cultivars grown in the subtropics often fail to accumulate sufficient anthocyanins to achieve good uniform berry color. Growers of V. vinifera table grapes in temperate regions generally use ethephon and, more recently, (S-cis-abscisic acid (S-ABA to overcome this problem. The objective of this study was to determine if S-ABA applications at different timings and concentrations have an effect on anthocyanin regulatory and biosynthetic genes, pigment accumulation, and berry color of the Selection 21 cultivar, a new V. vinifera ×V. labrusca hybrid seedless grape that presents lack of red color when grown in subtropical areas. Applications of S-ABA 400 mg/L resulted in a higher accumulation of total anthocyanins and of the individual anthocyaninsanthocyanins: delphinidin-3-glucoside, cyanidin-3-glucoside, peonidin-3-glucoside, and malvidin-3-glucoside in the berry skin and improved the color attributes of the berries. Treatment with two applications at 7 days after véraison (DAV and 21 DAV of S-ABA 400 mg/L resulted in a higher accumulation of total anthocyanins in the skin of berries and increased the gene expression of CHI, F3H, DFR, and UFGT and of the VvMYBA1 and VvMYBA2 transcription factors in the seedless grape cultivar.

  18. Exogenous Abscisic Acid Promotes Anthocyanin Biosynthesis and Increased Expression of Flavonoid Synthesis Genes in Vitis vinifera × Vitis labrusca Table Grapes in a Subtropical Region

    Science.gov (United States)

    Koyama, Renata; Roberto, Sergio R.; de Souza, Reginaldo T.; Borges, Wellington F. S.; Anderson, Mauri; Waterhouse, Andrew L.; Cantu, Dario; Fidelibus, Matthew W.; Blanco-Ulate, Barbara

    2018-01-01

    Hybrid (Vitis vinifera ×Vitis labrusca) table grape cultivars grown in the subtropics often fail to accumulate sufficient anthocyanins to achieve good uniform berry color. Growers of V. vinifera table grapes in temperate regions generally use ethephon and, more recently, (S)-cis-abscisic acid (S-ABA) to overcome this problem. The objective of this study was to determine if S-ABA applications at different timings and concentrations have an effect on anthocyanin regulatory and biosynthetic genes, pigment accumulation, and berry color of the Selection 21 cultivar, a new V. vinifera ×V. labrusca hybrid seedless grape that presents lack of red color when grown in subtropical areas. Applications of S-ABA 400 mg/L resulted in a higher accumulation of total anthocyanins and of the individual anthocyaninsanthocyanins: delphinidin-3-glucoside, cyanidin-3-glucoside, peonidin-3-glucoside, and malvidin-3-glucoside in the berry skin and improved the color attributes of the berries. Treatment with two applications at 7 days after véraison (DAV) and 21 DAV of S-ABA 400 mg/L resulted in a higher accumulation of total anthocyanins in the skin of berries and increased the gene expression of CHI, F3H, DFR, and UFGT and of the VvMYBA1 and VvMYBA2 transcription factors in the seedless grape cultivar. PMID:29632542

  19. A SHATTERPROOF-like gene controls ripening in non-climacteric strawberries, and auxin and abscisic acid antagonistically affect its expression.

    Science.gov (United States)

    Daminato, Margherita; Guzzo, Flavia; Casadoro, Giorgio

    2013-09-01

    Strawberries (Fragaria×ananassa) are false fruits the ripening of which follows the non-climacteric pathway. The role played by a C-type MADS-box gene [SHATTERPROOF-like (FaSHP)] in the ripening of strawberries has been studied by transiently modifying gene expression through either over-expression or RNA-interference-mediated down-regulation. The altered expression of the FaSHP gene caused a change in the time taken by the over-expressing and the down- regulated fruits to attain the pink stage, which was slightly shorter and much longer, respectively, compared to controls. In parallel with the modified ripening times, the metabolome components and the expression of ripening-related genes also appeared different in the transiently modified fruits. Differences in the response time of the analysed genes suggest that FaSHP can control the expression of ripening genes either directly or indirectly through other transcription factor-encoding genes. Because fleshy strawberries are false fruits these results indicate that C-type MADS-box genes like SHATTERPROOF may act as modulators of ripening in fleshy fruit-like structures independently of their anatomical origin. Treatment of strawberries with either auxin or abscisic acid had antagonistic impacts on both the expression of FaSHP and the expression of ripening-related genes and metabolome components.

  20. Differential expression of gibberellin- and abscisic acid-related genes implies their roles in the bud activity-dormancy transition of tea plants.

    Science.gov (United States)

    Yue, Chuan; Cao, Hongli; Hao, Xinyuan; Zeng, Jianming; Qian, Wenjun; Guo, Yuqiong; Ye, Naixing; Yang, Yajun; Wang, Xinchao

    2018-03-01

    Thirty genes involved in GA and ABA metabolism and signalling were identified, and the expression profiles indicated that they play crucial roles in the bud activity-dormancy transition in tea plants. Gibberellin (GA) and abscisic acid (ABA) are fundamental phytohormones that extensively regulate plant growth and development, especially bud dormancy and sprouting transition in perennial plants. However, there is little information on GA- and ABA-related genes and their expression profiles during the activity-dormancy transition in tea plants. In the present study, 30 genes involved in the metabolism and signalling pathways of GA and ABA were first identified, and their expression patterns in different tissues were assessed. Further evaluation of the expression patterns of selected genes in response to GA 3 and ABA application showed that CsGA3ox, CsGA20ox, CsGA2ox, CsZEP and CsNCED transcripts were differentially expressed after exogenous treatment. The expression profiles of the studied genes during winter dormancy and spring sprouting were investigated, and somewhat diverse expression patterns were found for GA- and ABA-related genes. This diversity was associated with the bud activity-dormancy cycle of tea plants. These results indicate that the genes involved in the metabolism and signalling of GA and ABA are important for regulating the bud activity-dormancy transition in tea plants.

  1. Putrescine Is Involved in Arabidopsis Freezing Tolerance and Cold Acclimation by Regulating Abscisic Acid Levels in Response to Low Temperature1

    Science.gov (United States)

    Cuevas, Juan C.; López-Cobollo, Rosa; Alcázar, Rubén; Zarza, Xavier; Koncz, Csaba; Altabella, Teresa; Salinas, Julio; Tiburcio, Antonio F.; Ferrando, Alejandro

    2008-01-01

    The levels of endogenous polyamines have been shown to increase in plant cells challenged with low temperature; however, the functions of polyamines in the regulation of cold stress responses are unknown. Here, we show that the accumulation of putrescine under cold stress is essential for proper cold acclimation and survival at freezing temperatures because Arabidopsis (Arabidopsis thaliana) mutants defective in putrescine biosynthesis (adc1, adc2) display reduced freezing tolerance compared to wild-type plants. Genes ADC1 and ADC2 show different transcriptional profiles upon cold treatment; however, they show similar and redundant contributions to cold responses in terms of putrescine accumulation kinetics and freezing sensitivity. Our data also demonstrate that detrimental consequences of putrescine depletion during cold stress are due, at least in part, to alterations in the levels of abscisic acid (ABA). Reduced expression of NCED3, a key gene involved in ABA biosynthesis, and down-regulation of ABA-regulated genes are detected in both adc1 and adc2 mutant plants under cold stress. Complementation analysis of adc mutants with ABA and reciprocal complementation tests of the aba2-3 mutant with putrescine support the conclusion that putrescine controls the levels of ABA in response to low temperature by modulating ABA biosynthesis and gene expression. PMID:18701673

  2. Osabc1k8, an abc1-like kinase gene, mediates abscisic acid sensitivity and dehydration tolerance response in rice seedlings

    International Nuclear Information System (INIS)

    Liu, Y.; Li, T.; Yang, C.

    2015-01-01

    The activity of bc1 complex kinase (ABC1K) protein family, which widely exists in prokaryotes and eukaryotes, consists of 15 members in rice, and the role of this family in plants has not yet been studied in details. In this study, a novel function of OsABC1K8 (LOC-Os06g48770), a member of rice ABC1K family, was characterized. The transcript level of OsABC1K8 changes in response to salt, dehydration, cold, PEG, oxidative (H/sub 2/O/sub 2/) stresses, or abscisic acid (ABA) treatment. Overexpression of OsABC1K8 significantly increased sensitivity to dehydration and reduced sensitivity to ABA. In the contrast, RNAi transgenic lines displayed significantly reduced sensitivity to dehydration stress and increased sensitivity to ABA. Furthermore, the transcriptional levels of several ABA/stress-regulated responsive genes were suppressed in OsABC1K8 over-expressing plants under dehydration stress. In conclusion, our results suggested that OsABC1K8 is a negative regulator in response to dehydration stress through an ABA-dependent pathway. (author)

  3. Development of a rapid LC-DAD/FLD method for the simultaneous determination of auxins and abscisic acid in plant extracts.

    Science.gov (United States)

    Bosco, Renato; Caser, Matteo; Vanara, Francesca; Scariot, Valentina

    2013-11-20

    Plant hormones play a crucial role in controlling plant growth and development. These groups of naturally occurring substances trigger physiological processes at very low concentrations, which mandate sensitive techniques for their quantitation. This paper describes a method to quantify endogenous (±)-2-cis-4-trans-abscisic acid, indole-3-acetic acid, indole-3-propionic acid, and indole-3-butyric acid. The method combines high-performance liquid chromatography (HPLC) with diode array and fluorescence detection in a single run. Hybrid tea rose 'Monferrato' matrices (leaves, petals, roots, seeds, androecium, gynoecium, and pollen) were used as references. Rose samples were separated and suspended in extracting methanol, after which (±)-2-cis-4-trans-abscisic acid and auxins were extracted by solvent extraction. Sample solutions were added first to cation solid phase extraction (SPE) cartridges and the eluates to anion SPE cartridges. The acidic hormones were bound to the last column and eluted with 5% phosphoric acid in methanol. Experimental results showed that this approach can be successfully applied to real samples and that sample preparation and total time for routine analysis can be greatly reduced.

  4. Relationship among color development, anthocyanin and pigment-related gene expression in 'Crimson Seedless' grapes treated with abscisic acid and sucrose.

    Science.gov (United States)

    Olivares, Daniela; Contreras, Carolina; Muñoz, Victoria; Rivera, Sebastián; González-Agüero, Mauricio; Retamales, Julio; Defilippi, Bruno G

    2017-06-01

    'Crimson Seedless' is one of the most important table grape varieties in Chile, but under certain environmental conditions, the fruit exhibits inadequate red color development, causing economic losses due to lower product quality. The use of plant growth regulators, such as abscisic acid (ABA) and ethylene, during development increases the anthocyanin content of the skin, improving the color of the berry. Recently, sucrose has been identified as a signaling molecule capable of regulating the expression of genes of the anthocyanin biosynthesis pathway. The aim of this study was to analyze the effect of application of ABA and/or sucrose on color development and their relationship with anthocyanin metabolism. Applications of ABA (400 ppm or 200 ppm) and/or sucrose (90 mM) were performed close to the véraison stage. During development and at harvest, quality attributes such as berry firmness, total soluble solids and titratable acidity were not affected by these treatments. Increased red color development was observed in fruits treated with ABA and/or sucrose, due to accumulation of anthocyanins. Fruits subjected to sucrose treatment showed higher levels of anthocyanins than untreated fruits but lower levels than fruits treated with ABA. Increased expression of genes involved in anthocyanin biosynthesis was observed in ABA- and sucrose-treated fruits compared to untreated fruits. Based on these findings, we demonstrated that sucrose improved fruit color development by increasing synthesis and accumulation of anthocyanins, thus allowing earlier harvests and improving table grape quality. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  5. Overexpression of OsWRKY72 gene interferes in the abscisic acid ...

    Indian Academy of Sciences (India)

    Prakash

    WRKY75 transcription factor is a modulator of phosphate acquisition and root development in Arabidopsis; Plant Physiol. 143 1789–1801. Du L Q and Chen Z X 2000 Identification of genes encoding receptor-like protein kinases as possible targets of pathogen- and salicylic acid-induced WRKY DNA-binding proteins in.

  6. Overexpression of sweet sorghum cryptochrome 1a confers hypersensitivity to blue light, abscisic acid and salinity in Arabidopsis.

    Science.gov (United States)

    Zhou, Tingting; Meng, Lingyang; Ma, Yue; Liu, Qing; Zhang, Yunyun; Yang, Zhenming; Yang, Deguang; Bian, Mingdi

    2018-02-01

    This work provides the bioinformatics, expression pattern and functional analyses of cryptochrome 1a from sweet sorghum (SbCRY1a), together with an exploration of the signaling mechanism mediated by SbCRY1a. Sweet sorghum [Sorghum bicolor (L.) Moench] is considered to be an ideal candidate for biofuel production due to its high efficiency of photosynthesis and the ability to maintain yield under harsh environmental conditions. Blue light receptor cryptochromes regulate multiple aspects of plant growth and development. Here, we reported the function and signal mechanism of sweet sorghum cryptochrome 1a (SbCRY1a) to explore its potential for genetic improvement of sweet sorghum varieties. SbCRY1a transcripts experienced almost 24 h diurnal cycling; however, its protein abundance showed no oscillation. Overexpression of SbCRY1a in Arabidopsis rescued the phenotype of cry1 mutant in a blue light-specific manner and regulated HY5 accumulation under blue light. SbCRY1a protein was present in both nucleus and cytoplasm. The photoexcited SbCRY1a interacted directly with a putative RING E3 ubiquitin ligase constitutive photomorphogenesis 1 (COP1) from sweet sorghum (SbCOP1) instead of SbSPA1 to suppress SbCOP1-SbHY5 interaction responding to blue light. These observations indicate that the function and signaling mechanism of cryptochromes are basically conservative between monocotyledons and dicotyledons. Moreover, SbCRY1a-overexpressed transgenic Arabidopsis showed oversensitive to abscisic acid (ABA) and salinity. The ABA-responsive gene ABI5 was up-regulated evidently in SbCRY1a transgenic lines, suggesting that SbCRY1a might regulate ABA signaling through the HY5-ABI5 regulon.

  7. Expression Analysis of Four Peroxiredoxin Genes from Tamarix hispida in Response to Different Abiotic Stresses and Exogenous Abscisic Acid (ABA

    Directory of Open Access Journals (Sweden)

    Guiyan Yang

    2012-03-01

    Full Text Available Peroxiredoxins (Prxs are a recently discovered family of antioxidant enzymes that catalyze the reduction of peroxides and alkyl peroxides. In this study, four Prx genes (named as ThPrxII, ThPrxIIE, ThPrxIIF, and Th2CysPrx were cloned from Tamarix hispida. Their expression profiles in response to stimulus of NaCl, NaHCO3, PEG, CdCl2 and abscisic acid (ABA in roots, stems and leaves of T. hispida were investigated using real-time RT-PCR. The results showed that the four ThPrxs were all expressed in roots, stems and leaves. Furthermore, the transcript levels of ThPrxIIE and ThPrxII were the lowest and the highest, respectively, in all tissue types. All the ThPrx genes were induced by both NaCl and NaHCO3 and reached their highest expression levels at the onset of stress in roots. Under PEG and CdCl2 stress, the expression patterns of these ThPrxs showed temporal and spatial specificity. The expressions of the ThPrxs were all differentially regulated by ABA, indicating that they are all involved in the ABA signaling pathway. These findings reveal a complex regulation of Prxs that is dependent on the type of Prx, tissue, and the signaling molecule. The divergence of the stress-dependent transcriptional regulation of the ThPrx gene family in T. hispida may provide an essential basis for the elucidation of Prx function in future work.

  8. Expression analysis of four peroxiredoxin genes from Tamarix hispida in response to different abiotic stresses and Exogenous Abscisic Acid (ABA).

    Science.gov (United States)

    Gao, Caiqiu; Zhang, Kaimin; Yang, Guiyan; Wang, Yucheng

    2012-01-01

    Peroxiredoxins (Prxs) are a recently discovered family of antioxidant enzymes that catalyze the reduction of peroxides and alkyl peroxides. In this study, four Prx genes (named as ThPrxII, ThPrxIIE, ThPrxIIF, and Th2CysPrx) were cloned from Tamarix hispida. Their expression profiles in response to stimulus of NaCl, NaHCO(3), PEG, CdCl(2) and abscisic acid (ABA) in roots, stems and leaves of T. hispida were investigated using real-time RT-PCR. The results showed that the four ThPrxs were all expressed in roots, stems and leaves. Furthermore, the transcript levels of ThPrxIIE and ThPrxII were the lowest and the highest, respectively, in all tissue types. All the ThPrx genes were induced by both NaCl and NaHCO(3) and reached their highest expression levels at the onset of stress in roots. Under PEG and CdCl(2) stress, the expression patterns of these ThPrxs showed temporal and spatial specificity. The expressions of the ThPrxs were all differentially regulated by ABA, indicating that they are all involved in the ABA signaling pathway. These findings reveal a complex regulation of Prxs that is dependent on the type of Prx, tissue, and the signaling molecule. The divergence of the stress-dependent transcriptional regulation of the ThPrx gene family in T. hispida may provide an essential basis for the elucidation of Prx function in future work.

  9. Abscisic acid, a stress hormone helps in improving water relations and yield of sunflower (helianthus annuus l.) hybrids under drought

    International Nuclear Information System (INIS)

    Hussain, S.; Saleem, M.F.; Cheema, M.A.; Ashraf, M.Y.; Haq, M.A.

    2010-01-01

    Genotypic variation in water relations under drought is an important index of studying drought tolerance of crops. Abscisic acid (ABA) application helped in mitigating drought stress by improving water relations and yield. Three sunflower hybrids viz., DK-4040 (tall stature), S-278 (medium stature) and SF-187 (short stature) were subjected to different irrigation and ABA application regimes i.e., four irrigations (25 days after sowing (DAS), at bud initiation, at flower initiation and at achene formation) and with no ABA spray, three irrigations (25 days after sowing, at flower initiation and at achene formation) and with no ABA spray, three irrigations (25 days after sowing, at flower initiation and at achene formation) and with ABA spray at bud initiation, three irrigations (25 days after sowing), at bud initiation and at achene formation) and with no ABA spray, three irrigations (25 days after sowing), at bud initiation and at achene formation) and with ABA spray at flower initiation. The experiment was laid out in randomized complete block design with split plot arrangement and had three replications. Exogenous application of ABA under drought at either stage (bud or flower initiation) was helpful in ameliorating drought stress by improving water relations and yield of sunflower hybrids; however response was better when ABA was applied under drought at bud initiation than at flower initiation stage. Sunflower hybrid DK- 4040 showed better enhancement of drought tolerance by exogenous application of ABA under drought than SF-187 and S-278 because it showed more improvement in water potential, osmotic potential, turgor pressure, relative leaf water contents and achene yield. (author)

  10. Abscisic acid refines the synthesis of chloroplast proteins in maize (Zea mays in response to drought and light.

    Directory of Open Access Journals (Sweden)

    Xiuli Hu

    Full Text Available To better understand abscisic acid (ABA regulation of the synthesis of chloroplast proteins in maize (Zea mays L. in response to drought and light, we compared leaf proteome differences between maize ABA-deficient mutant vp5 and corresponding wild-type Vp5 green and etiolated seedlings exposed to drought stress. Proteins extracted from the leaves of Vp5 and vp5 seedlings were used for two-dimensional electrophoresis (2-DE and subsequent matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF mass spectrometry (MS. After Coomassie brilliant blue staining, approximately 450 protein spots were reproducibly detected on 2-DE gels. A total of 36 differentially expressed protein spots in response to drought and light were identified using MALDI-TOF MS and their subcellular localization was determined based on the annotation of reviewed accession in UniProt Knowledgebase and the software prediction. As a result, corresponding 13 proteins of the 24 differentially expressed protein spots were definitely localized in chloroplasts and their expression was in an ABA-dependent way, including 6 up-regulated by both drought and light, 5 up-regulated by drought but down-regulated by light, 5 up-regulated by light but down-regulated by drought; 5 proteins down-regulated by drought were mainly those involved in photosynthesis and ATP synthesis. Thus, the results in the present study supported the vital role of ABA in regulating the synthesis of drought- and/or light-induced proteins in maize chloroplasts and would facilitate the functional characterization of ABA-induced chloroplast proteins in C(4 plants.

  11. Abscisic acid (ABA) regulates grape bud dormancy, and dormancy release stimuli may act through modification of ABA metabolism.

    Science.gov (United States)

    Zheng, Chuanlin; Halaly, Tamar; Acheampong, Atiako Kwame; Takebayashi, Yumiko; Jikumaru, Yusuke; Kamiya, Yuji; Or, Etti

    2015-03-01

    In warm-winter regions, induction of dormancy release by hydrogen cyanamide (HC) is mandatory for commercial table grape production. Induction of respiratory stress by HC leads to dormancy release via an uncharacterized biochemical cascade that could reveal the mechanism underlying this phenomenon. Previous studies proposed a central role for abscisic acid (ABA) in the repression of bud meristem activity, and suggested its removal as a critical step in the HC-induced cascade. In the current study, support for these assumptions was sought. The data show that ABA indeed inhibits dormancy release in grape (Vitis vinifera) buds and attenuates the advancing effect of HC. However, HC-dependent recovery was detected, and was affected by dormancy status. HC reduced VvXERICO and VvNCED transcript levels and induced levels of VvABA8'OH homologues. Regulation of these central players in ABA metabolism correlated with decreased ABA and increased ABA catabolite levels in HC-treated buds. Interestingly, an inhibitor of ethylene signalling attenuated these effects of HC on ABA metabolism. HC also modulated the expression of ABA signalling regulators, in a manner that supports a decreased ABA level and response. Taken together, the data support HC-induced removal of ABA-mediated repression via regulation of ABA metabolism and signalling. Expression profiling during the natural dormancy cycle revealed that at maximal dormancy, the HC-regulated VvNCED1 transcript level starts to drop. In parallel, levels of VvA8H-CYP707A4 transcript and ABA catabolites increase sharply. This may provide initial support for the involvement of ABA metabolism also in the execution of natural dormancy. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  12. Abscisic acid promotion of arbuscular mycorrhizal colonization requires a component of the PROTEIN PHOSPHATASE 2A complex.

    Science.gov (United States)

    Charpentier, Myriam; Sun, Jongho; Wen, Jiangqi; Mysore, Kirankumar S; Oldroyd, Giles E D

    2014-12-01

    Legumes can establish intracellular interactions with symbiotic microbes to enhance their fitness, including the interaction with arbuscular mycorrhizal (AM) fungi. AM fungi colonize root epidermal cells to gain access to the root cortex, and this requires the recognition by the host plant of fungus-made mycorrhizal factors. Genetic dissection has revealed the symbiosis signaling pathway that allows the recognition of AM fungi, but the downstream processes that are required to promote fungal infection are poorly understood. Abscisic acid (ABA) has been shown to promote arbuscule formation in tomato (Solanum lycopersicum). Here, we show that ABA modulates the establishment of the AM symbiosis in Medicago truncatula by promoting fungal colonization at low concentrations and impairing it at high concentrations. We show that the positive regulation of AM colonization via ABA requires a PROTEIN PHOSPHATASE 2A (PP2A) holoenzyme subunit, PP2AB'1. Mutations in PP2AB'1 cause reduced levels of AM colonization that cannot be rescued with permissive ABA application. The action of PP2AB'1 in response to ABA is unlinked to the generation of calcium oscillations, as the pp2aB'1 mutant displays a normal calcium response. This contrasts with the application of high concentrations of ABA that impairs mycorrhizal factor-induced calcium oscillations, suggesting different modes of action of ABA on the AM symbiosis. Our work reveals that ABA functions at multiple levels to regulate the AM symbiosis and that a PP2A phosphatase is required for the ABA promotion of AM colonization. © 2014 American Society of Plant Biologists. All Rights Reserved.

  13. Arabidopsis plastid AMOS1/EGY1 integrates abscisic acid signaling to regulate global gene expression response to ammonium stress

    KAUST Repository

    Li, Baohai

    2012-10-12

    Ammonium (NH4 +) is a ubiquitous intermediate of nitrogen metabolism but is notorious for its toxic effects on most organisms. Extensive studies of the underlying mechanisms of NH4 + toxicity have been reported in plants, but it is poorly understood how plants acclimate to high levels of NH4 +. Here, we identified an Arabidopsis (Arabidopsis thaliana) mutant, ammonium overly sensitive1 (amos1), that displays severe chlorosis under NH4 + stress. Map-based cloning shows amos1 to carry a mutation in EGY1 (for ethylene-dependent, gravitropism-deficient, and yellow-green-like protein1), which encodes a plastid metalloprotease. Transcriptomic analysis reveals that among the genes activated in response to NH4 +, 90% are regulated dependent on AMOS1/ EGY1. Furthermore, 63% of AMOS1/EGY1-dependent NH4 +-activated genes contain an ACGTG motif in their promoter region, a core motif of abscisic acid (ABA)-responsive elements. Consistent with this, our physiological, pharmacological, transcriptomic, and genetic data show that ABA signaling is a critical, but not the sole, downstream component of the AMOS1/EGY1-dependent pathway that regulates the expression of NH4 +-responsive genes and maintains chloroplast functionality under NH4 + stress. Importantly, abi4 mutants defective in ABA-dependent and retrograde signaling, but not ABA-deficient mutants, mimic leaf NH4 + hypersensitivity of amos1. In summary, our findings suggest that an NH4 +-responsive plastid retrograde pathway, which depends on AMOS1/EGY1 function and integrates with ABA signaling, is required for the regulation of expression of the presence of high NH4 + levels. © 2012 American Society of Plant Biologists. All Rights Reserved.

  14. Functional roles of the pepper RING finger protein gene, CaRING1, in abscisic acid signaling and dehydration tolerance.

    Science.gov (United States)

    Lim, Chae Woo; Hwang, Byung Kook; Lee, Sung Chul

    2015-09-01

    Plants are constantly exposed to a variety of biotic and abiotic stresses, which include pathogens and conditions of high salinity, low temperature, and drought. Abscisic acid (ABA) is a major plant hormone involved in signal transduction pathways that mediate the defense response of plants to abiotic stress. Previously, we isolated Ring finger protein gene (CaRING1) from pepper (Capsicum annuum), which is associated with resistance to bacterial pathogens, accompanied by hypersensitive cell death. Here, we report a new function of the CaRING1 gene product in the ABA-mediated defense responses of plants to dehydration stress. The expression of the CaRING1 gene was induced in pepper leaves treated with ABA or exposed to dehydration or NaCl. Virus-induced gene silencing of CaRING1 in pepper plants exhibited low degree of ABA-induced stomatal closure and high levels of transpirational water loss in dehydrated leaves. These led to be more vulnerable to dehydration stress in CaRING1-silenced pepper than in the control pepper, accompanied by reduction of ABA-regulated gene expression and low accumulation of ABA and H2O2. In contrast, CaRING1-overexpressing transgenic plants showed enhanced sensitivity to ABA during the seedling growth and establishment. These plants were also more tolerant to dehydration stress than the wild-type plants because of high ABA accumulation, enhanced stomatal closure and increased expression of stress-responsive genes. Together, these results suggest that the CaRING1 acts as positive factor for dehydration tolerance in Arabidopsis by modulating ABA biosynthesis and ABA-mediated stomatal closing and gene expression.

  15. HRS1 Acts as a Negative Regulator of Abscisic Acid Signaling to Promote Timely Germination of Arabidopsis Seeds

    Science.gov (United States)

    Wang, Ran; Liu, Hong; Yang, Huixia; Rodriguez, Pedro L.; Qin, Huanju; Liu, Xin; Wang, Daowen

    2012-01-01

    In this work, we conducted functional analysis of Arabidopsis HRS1 gene in order to provide new insights into the mechanisms governing seed germination. Compared with wild type (WT) control, HRS1 knockout mutant (hrs1-1) exhibited significant germination delays on either normal medium or those supplemented with abscisic acid (ABA) or sodium chloride (NaCl), with the magnitude of the delay being substantially larger on the latter media. The hypersensitivity of hrs1-1 germination to ABA and NaCl required ABI3, ABI4 and ABI5, and was aggravated in the double mutant hrs1-1abi1-2 and triple mutant hrs1-1hab1-1abi1-2, indicating that HRS1 acts as a negative regulator of ABA signaling during seed germination. Consistent with this notion, HRS1 expression was found in the embryo axis, and was regulated both temporally and spatially, during seed germination. Further analysis showed that the delay of hrs1-1 germination under normal conditions was associated with reduction in the elongation of the cells located in the lower hypocotyl (LH) and transition zone (TZ) of embryo axis. Interestingly, the germination rate of hrs1-1 was more severely reduced by the inhibitor of cell elongation, and more significantly decreased by the suppressors of plasmalemma H+-ATPase activity, than that of WT control. The plasmalemma H+-ATPase activity in the germinating seeds of hrs1-1 was substantially lower than that exhibited by WT control, and fusicoccin, an activator of this pump, corrected the transient germination delay of hrs1-1. Together, our data suggest that HRS1 may be needed for suppressing ABA signaling in germinating embryo axis, which promotes the timely germination of Arabidopsis seeds probably by facilitating the proper function of plasmalemma H+-ATPase and the efficient elongation of LH and TZ cells. PMID:22545134

  16. Structural basis for basal activity and autoactivation of abscisic acid (ABA) signaling SnRK2 kinases

    Energy Technology Data Exchange (ETDEWEB)

    Ng, Ley-Moy; Soon, Fen-Fen; Zhou, X. Edward; West, Graham M.; Kovach, Amanda; Suino-Powell, Kelly M.; Chalmers, Michael J.; Li, Jun; Yong, Eu-Leong; Zhu, Jian-Kang; Griffin, Patrick R.; Melcher, Karsten; Xu, H. Eric (Van Andel); (Scripps); (Purdue); (NU Singapore)

    2014-10-02

    Abscisic acid (ABA) is an essential hormone that controls plant growth, development, and responses to abiotic stresses. Central for ABA signaling is the ABA-mediated autoactivation of three monomeric Snf1-related kinases (SnRK2.2, -2.3, and -2.6). In the absence of ABA, SnRK2s are kept in an inactive state by forming physical complexes with type 2C protein phosphatases (PP2Cs). Upon relief of this inhibition, SnRK2 kinases can autoactivate through unknown mechanisms. Here, we report the crystal structures of full-length Arabidopsis thaliana SnRK2.3 and SnRK2.6 at 1.9- and 2.3-{angstrom} resolution, respectively. The structures, in combination with biochemical studies, reveal a two-step mechanism of intramolecular kinase activation that resembles the intermolecular activation of cyclin-dependent kinases. First, release of inhibition by PP2C allows the SnRK2s to become partially active because of an intramolecular stabilization of the catalytic domain by a conserved helix in the kinase regulatory domain. This stabilization enables SnRK2s to gain full activity by activation loop autophosphorylation. Autophosphorylation is more efficient in SnRK2.6, which has higher stability than SnRK2.3 and has well-structured activation loop phosphate acceptor sites that are positioned next to the catalytic site. Together, these data provide a structural framework that links ABA-mediated release of PP2C inhibition to activation of SnRK2 kinases.

  17. AtPP2CG1, a protein phosphatase 2C, positively regulates salt tolerance of Arabidopsis in abscisic acid-dependent manner

    International Nuclear Information System (INIS)

    Liu, Xin; Zhu, Yanming; Zhai, Hong; Cai, Hua; Ji, Wei; Luo, Xiao; Li, Jing; Bai, Xi

    2012-01-01

    Highlights: ► AtPP2CG1 positively regulates salt tolerance in ABA-dependent manner. ► AtPP2CG1 up-regulates the expression of marker genes in different pathways. ► AtPP2CG1 expresses in the vascular system and trichomes of Arabidopsis. -- Abstract: AtPP2CG1 (Arabidopsis thaliana protein phosphatase 2C G Group 1) was predicted as an abiotic stress candidate gene by bioinformatic analysis in our previous study. The gene encodes a putative protein phosphatase 2C that belongs to Group G of PP2C. There is no report of Group G genes involved in abiotic stress so far. Real-time RT-PCR analysis showed that AtPP2CG1 expression was induced by salt, drought, and abscisic acid (ABA) treatment. The expression levels of AtPP2CG1 in the ABA synthesis-deficient mutant abi2–3 were much lower than that in WT plants under salt stress suggesting that the expression of AtPP2CG1 acts in an ABA-dependent manner. Over-expression of AtPP2CG1 led to enhanced salt tolerance, whereas its loss of function caused decreased salt tolerance. These results indicate that AtPP2CG1 positively regulates salt stress in an ABA-dependent manner. Under salt treatment, AtPP2CG1 up-regulated the expression levels of stress-responsive genes, including RD29A, RD29B, DREB2A and KIN1. GUS activity was detected in roots, leaves, stems, flower, and trichomes of AtPP2CG1 promoter–GUS transgenic plants. AtPP2CG1 protein was localized in nucleus and cytoplasm via AtPP2CG1:eGFP and YFP:AtPP2CG1 fusion approaches.

  18. Visualisation of abscisic acid and 12-oxo-phytodienoic acid in immature Phaseolus vulgaris L. seeds using desorption electrospray ionisation-imaging mass spectrometry

    Science.gov (United States)

    Enomoto, Hirofumi; Sensu, Takuya; Sato, Kei; Sato, Futoshi; Paxton, Thanai; Yumoto, Emi; Miyamoto, Koji; Asahina, Masashi; Yokota, Takao; Yamane, Hisakazu

    2017-02-01

    The plant hormone abscisic acid (ABA) and the jasmonic acid related-compound 12-oxo-phytodienoic acid (OPDA) play crucial roles in seed development, dormancy, and germination. However, a lack of suitable techniques for visualising plant hormones has restricted the investigation of their biological mechanisms. In the present study, desorption electrospray ionisation-imaging mass spectrometry (DESI-IMS), a powerful tool for visualising metabolites in biological tissues, was used to visualise ABA and OPDA in immature Phaseolus vulgaris L. seed sections. The mass spectra, peak values and chemical formulae obtained from the analysis of seed sections were consistent with those determined for ABA and OPDA standards, as were the precursor and major fragment ions observed in tandem mass spectrometry (MS/MS) imaging. Furthermore, the precursor and fragment ion images showed similar distribution patterns. In addition, the localisation of ABA and OPDA using DESI-IMS was confirmed using liquid chromatography-MS/MS (LC-MS/MS). The results indicated that ABA was mainly distributed in the radical and cotyledon of the embryo, whereas OPDA was distributed exclusively in external structures, such as the hilum and seed coat. The present study is the first to report the visualisation of plant hormones using IMS, and demonstrates that DESI-IMS is a promising technique for future plant hormone research.

  19. Visualisation of abscisic acid and 12-oxo-phytodienoic acid in immature Phaseolus vulgaris L. seeds using desorption electrospray ionisation-imaging mass spectrometry.

    Science.gov (United States)

    Enomoto, Hirofumi; Sensu, Takuya; Sato, Kei; Sato, Futoshi; Paxton, Thanai; Yumoto, Emi; Miyamoto, Koji; Asahina, Masashi; Yokota, Takao; Yamane, Hisakazu

    2017-02-17

    The plant hormone abscisic acid (ABA) and the jasmonic acid related-compound 12-oxo-phytodienoic acid (OPDA) play crucial roles in seed development, dormancy, and germination. However, a lack of suitable techniques for visualising plant hormones has restricted the investigation of their biological mechanisms. In the present study, desorption electrospray ionisation-imaging mass spectrometry (DESI-IMS), a powerful tool for visualising metabolites in biological tissues, was used to visualise ABA and OPDA in immature Phaseolus vulgaris L. seed sections. The mass spectra, peak values and chemical formulae obtained from the analysis of seed sections were consistent with those determined for ABA and OPDA standards, as were the precursor and major fragment ions observed in tandem mass spectrometry (MS/MS) imaging. Furthermore, the precursor and fragment ion images showed similar distribution patterns. In addition, the localisation of ABA and OPDA using DESI-IMS was confirmed using liquid chromatography-MS/MS (LC-MS/MS). The results indicated that ABA was mainly distributed in the radical and cotyledon of the embryo, whereas OPDA was distributed exclusively in external structures, such as the hilum and seed coat. The present study is the first to report the visualisation of plant hormones using IMS, and demonstrates that DESI-IMS is a promising technique for future plant hormone research.

  20. Dynamic subnuclear relocalisation of WRKY40 in response to Abscisic acid in Arabidopsis thaliana

    OpenAIRE

    Geilen, Katja; B?hmer, Maik

    2015-01-01

    WRKY18, WRKY40 and WRKY60 are members of the WRKY transcription factor family and function as transcriptional regulators in ABA signal transduction in Arabidopsis thaliana. Here we show that WRKY18 and WRKY40, but not WRKY60, co-localise with PIF3, PIF4 and PHYB to Phytochrome B-containing nuclear bodies (PNBs). Localisation to the PNBs is phosphorylation-dependent and is inhibited by the general Ser/Thr-kinase inhibitor Staurosporine. Upon ABA treatment, WRKY40 relocalises from PNBs to the n...

  1. Dynamic subnuclear relocalisation of WRKY40 in response to Abscisic acid in Arabidopsis thaliana.

    Science.gov (United States)

    Geilen, Katja; Böhmer, Maik

    2015-08-21

    WRKY18, WRKY40 and WRKY60 are members of the WRKY transcription factor family and function as transcriptional regulators in ABA signal transduction in Arabidopsis thaliana. Here we show that WRKY18 and WRKY40, but not WRKY60, co-localise with PIF3, PIF4 and PHYB to Phytochrome B-containing nuclear bodies (PNBs). Localisation to the PNBs is phosphorylation-dependent and is inhibited by the general Ser/Thr-kinase inhibitor Staurosporine. Upon ABA treatment, WRKY40 relocalises from PNBs to the nucleoplasm in an OST1-dependent manner. This stimulus-induced relocalisation was not observed in response to other abiotic or biotic stimuli, including NaCl, MeJA or flg22 treatment. Bimolecular fluorescence complementation experiments indicate that while PIF3, PIF4 and PHYB physically interact in these bodies, PHYB, PIF3 and PIF4 do not interact with the two WRKY transcription factors, which may suggest a more general role for these bodies in regulation of transcriptional activity.

  2. Purification and determination of plant hormones auxin and abscisic acid using solid phase extraction and two-dimensional high performance liquid chromatography

    Czech Academy of Sciences Publication Activity Database

    Dobrev, Petre; Havlíček, Libor; Vágner, Martin; Malbeck, Jiří; Kamínek, Miroslav

    2005-01-01

    Roč. 1075, 1-2 (2005), s. 159-166 ISSN 0021-9673 R&D Projects: GA ČR GP522/02/D058; GA ČR GA206/02/0967; GA MŠk LN00A081; GA ČR GA522/04/0549; GA MZe QF4176 Institutional research plan: CEZ:AV0Z50380511 Keywords : Auxin * Abscisic acid * Solid phase extraction Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.096, year: 2005

  3. Local root abscisic acid (ABA) accumulation depends on the spatial distribution of soil moisture in potato: implications for ABA signalling under heterogeneous soil drying

    OpenAIRE

    Pu?rtolas, Jaime; Conesa, Mar?a R.; Ballester, Carlos; Dodd, Ian C.

    2014-01-01

    Patterns of root abscisic acid (ABA) accumulation ([ABA]root), root water potential (?root), and root water uptake (RWU), and their impact on xylem sap ABA concentration ([X-ABA]) were measured under vertical partial root-zone drying (VPRD, upper compartment dry, lower compartment wet) and horizontal partial root-zone drying (HPRD, two lateral compartments: one dry, the other wet) of potato (Solanum tuberosum L.). When water was withheld from the dry compartment for 0?10 d, RWU and ?root were...

  4. Copper suppresses abscisic acid catabolism and catalase activity, and inhibits seed germination of rice.

    Science.gov (United States)

    Ye, Nenghui; Li, Haoxuan; Zhu, Guohui; Liu, Yinggao; Liu, Rui; Xu, Weifeng; Jing, Yu; Peng, Xinxiang; Zhang, Jianhua

    2014-11-01

    Although copper (Cu) is an essential micronutrient for plants, a slight excess of Cu in soil can be harmful to plants. Unfortunately, Cu contamination is a growing problem all over the world due to human activities, and poses a soil stress to plant development. As one of the most important biological processes, seed germination is sensitive to Cu stress. However, little is known about the mechanism of Cu-induced inhibition of seed germination. In the present study, we investigated the relationship between Cu and ABA which is the predominant regulator of seed germination. Cu at a concentration of 30 µM effectively inhibited germination of rice caryopsis. ABA content in germinating seeds under copper stress was also higher than that under control conditions. Quantitative real-time PCR (qRT-PCR) revealed that Cu treatment reduced the expression of OsABA8ox2, a key gene of ABA catabolism in rice seeds. In addition, both malondialdehyde (MDA) and H2O2 contents were increased by Cu stress in the germinating seeds. Antioxidant enzyme assays revealed that only catalase activity was reduced by excess Cu, which was consistent with the mRNA profile of OsCATa during seed germination under Cu stress. Together, our results demonstrate that suppression of ABA catabolism and catalase (CAT) activity by excess Cu leads to the inhibition of seed germination of rice. © The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  5. Crucial roles of abscisic acid biogenesis in virulence of rice blast fungus Magnaporthe oryzae

    Directory of Open Access Journals (Sweden)

    Carla eSpence

    2015-12-01

    Full Text Available Rice suffers dramatic yield losses due to blast pathogen Magnaporthe oryzae. Pseudomonas chlororaphis EA105, a bacterium that was isolated from the rice rhizosphere, inhibits M. oryzae. It was shown previously that pre-treatment of rice with EA105 reduced the size of blast lesions through JA- and ETH-mediated ISR. ABA acts antagonistically towards SA, JA, and ETH signaling, to impede plant defense responses. EA105 may be reducing the virulence of M. oryzae by preventing the pathogen from up-regulating the key ABA biosynthetic gene NCED3 in rice roots, as well as a β-glucosidase likely involved in activating conjugated inactive forms of ABA. However, changes in total ABA concentrations were not apparent, provoking the question of whether ABA concentration is an indicator of ABA signaling and response. In the rice-M. oryzae interaction, ABA plays a dual role in disease severity by increasing plant susceptibility and accelerating pathogenesis in the fungus itself. ABA is biosynthesized by M. oryzae. Further, exogenous ABA increased spore germination and appressoria formation, distinct from other plant growth regulators. EA105, which inhibits appressoria formation, counteracted the virulence-promoting effects of ABA on M. oryzae. The role of endogenous fungal ABA in blast disease was confirmed through the inability of a knockout mutant impaired in ABA biosynthesis to form lesions on rice. Therefore, it appears that EA105 is invoking multiple strategies in its protection of rice from blast including direct mechanisms as well as those mediated through plant signaling. ABA is a molecule that is likely implicated in both tactics.

  6. Involvement of Arabidopsis RACK1 in Protein Translation and Its Regulation by Abscisic Acid

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Jianjun [University of British Columbia, Vancouver; Wang, Shucai [University of British Columbia, Vancouver; Valerius, Oliver [Universitaet Goettingen, Goettingen, Germany; Hall, Hardy [University of British Columbia, Vancouver; Zeng, Qingning [University of British Columbia, Vancouver; Li, Jian-Feng [Harvard University; Weston, David [ORNL; Ellis, Brian [University of British Columbia, Vancouver; Chen, Jay [ORNL

    2011-01-01

    Earlier studies have shown that RACK1 functions as a negative regulator of ABA responses in Arabidopsis, but the molecular mechanism of the action of RACK1 in these processes remains elusive. Global gene expression profiling revealed that approximately 40% of the genes affected by ABA treatment were affected in a similar manner by the rack1 mutation, supporting the view that RACK1 is an important regulator of ABA responses. On the other hand, co-expression analysis revealed that >80% of the genes co-expressed with RACK1 encode ribosome proteins, implying a close relationship between RACK1 s function and the ribosome complex. These results implied that the regulatory role for RACK1 in ABA responses may be partially due to its putative function in protein translation, which is one of the major cellular processes that mammalian and yeast RACK1 is involved in. Consistently, all three Arabidopsis RACK1 homologous genes, namely RACK1A, RACK1B and RACK1C, complemented the growth defects of the S. cerevisiae cpc2/rack1 mutant. In addition, RACK1 physically interacts with Arabidopsis Eukaryotic Initiation Factor 6 (eIF6), whose mammalian homologue is a key regulator of 80S ribosome assembly. Moreover, rack1 mutants displayed hypersensitivity to anisomycin, an inhibitor of protein translation, and displayed characteristics of impaired 80S functional ribosome assembly and 60S ribosomal subunit biogenesis in a ribosome profiling assay. Gene expression analysis revealed that ABA inhibits the expression of both RACK1 and eIF6. Taken together, these results suggest that RACK1 may be required for normal production of 60S and 80S ribosomes and that its action in these processes may be regulated by ABA.

  7. Effects of Ethephon and Abscisic Acid Application on Ripening-Related Genes in ‘Kohi’ Kiwifruit (Actinidia chinensis on the Vine

    Directory of Open Access Journals (Sweden)

    Kongsuwan Ampa

    2017-01-01

    Full Text Available The effects of ethephon and abscisic acid (ABA application on ripening-related genes of pre-harvest ‘Kohi’ kiwifruit (Actinidia chinensis were studied to clarify the possibility of the fruit ripening on the vine. The fruits were treated on the vine at mature stage with 250 µL⋅L−1 ethephon or 100 µmol⋅L−1 ABA, and the expression levels of chlorophyll synthase (AcCLS, chlorophyllase1 (AcCLH1, polygalacturonase (AcPG, expansin (AcEXP, β-amylase (Acβ-AM, sucrose synthase (AcSUSY, MADS-box SEPALLATA4/RIPENING INHIBITOR-like (AcSEP4/RIN and FRUITFUL-like (AcTDR4/FUL genes were analyzed. The expression levels of AcPG, AcEXP, Acβ-AM, and AcSUSY increased in the ethephon-treated fruit, but those of AcCLH1 at 6 and 9 days after treatment and AcCLS decreased. Moreover, the expression levels of AcSEP4/RIN and AcTDR4/FUL, the latter of which is associated with ethylene biosynthesis, were higher in the ethephon-treated fruit. The expression level of each gene in ABA-treated fruit was not significantly different from that of the untreated control. The results suggest that ethephon application increases the expression levels of AcPG, AcEXP, Acβ-AM, AcSUSY, AcSEP4/RIN, and AcTDR4/FUL in ‘Kohi’ kiwifruit on the vine.

  8. Exogenous abscisic acid application decreases cadmium accumulation in Arabidopsis plants, which is associated with the inhibition of IRT1-mediated cadmium uptake

    Directory of Open Access Journals (Sweden)

    Shi Kan eFan

    2014-12-01

    Full Text Available Cadmium (Cd contamination of agricultural soils is an increasingly serious problem. Measures need to be developed to minimise Cd entering the human food chain from contaminated soils. We report here that, under Cd exposure condition, application with low doses of (0.1–0.5 μM abscisic acid (ABA clearly inhibited Cd uptake by roots and decreased Cd level in Arabidopsis wild-type plants (Col-0. Expression of IRT1 in roots was also strongly inhibited by ABA treatment. Decrease in Cd uptake and the inhibition of IRT1 expression were clearly lesser pronounced in an ABA-insensitive double mutant snrk2.2/2.3 than in the Col-0 in response to ABA application. The ABA-decreased Cd uptake was found to correlate with the ABA-inhibited IRT1 expression in the roots of Col-0 plants fed two different levels of iron. Furthermore, the Cd uptake of irt1 mutants was barely affected by ABA application. These results indicated that inhibition of IRT1 expression is involved in the decrease of Cd uptake in response to exogenous ABA application. Interestingly, ABA application increased the iron level in both Col-0 plants and irt1 mutants, suggesting that ABA-increased Fe acquisition does not depend on the IRT1 function, but on the contrary, the ABA-mediated inhibition of IRT1 expression may be due to the elevation of iron level in plants. From our results, we concluded that ABA application might increase iron acquisition, followed by the decrease in Cd uptake by inhibition of IRT1 activity. Thus, for crop production in Cd contaminated soils, developing techniques based on ABA application potentially is a promising approach for reducing Cd accumulation in edible organs in plants.

  9. The synthesis and accumulation of resveratrol are associated with veraison and abscisic acid concentration in Beihong (Vitis vinifera × Vitis amurensis berry skin

    Directory of Open Access Journals (Sweden)

    Junfang Wang

    2016-11-01

    Full Text Available Resveratrols are polyphenolic secondary metabolites that can benefit human health, and only occur in a few plant families including Vitaceae. It has been reported that abscisic acid (ABA can induce veraison (the onset of grape berry ripening and may induce the accumulation of resveratrol in berry skin. However, the relationships between ABA, veraison, the accumulation of anthocyanins and the accumulation of resveratrol in the berry are poorly understood. This study attempted to answer this question through an investigation of the effect of applied ABA and fluridone (a synthetic inhibitor of ABA on the biosynthesis and accumulation of ABA, anthocyanin and resveratrol in Beihong (Vitis vinifera × Vitis amurensis berry skin. Under natural conditions, resveratrol concentration was very low before 91 DAA (days after anthesis, i.e. 2 weeks after veraison, however, it increased sharply from this point to 126 DAA (maturity. Exogenous ABA applications all resulted in an increase in berry skin ABA and anthocyanin concentration, irrespective of the developmental stage at which the treatment occurred (20 and 10 d pre-veraison,veraison or 7 d post-veraison, thereby advancing veraison. In contrast, resveratrol concentration increased only when ABA was applied at 10 d pre-veraison or at veraison. As a result, the accumulation of resveratrol was associated with veraison in grape berry skin and this accumulation, together with that of anthocyanins, was associated with ABA concentration. The response of resveratrol biosynthesis in the berry skin to manipulation of ABA varied during berry development and was less sensitive to ABA than the response of anthocyanin biosynthesis.

  10. Genome-wide gene expression profiling in Arabidopsis thaliana reveals new targets of abscisic acid and largely impaired gene regulation in the abi1-1 mutant.

    Science.gov (United States)

    Hoth, Stefan; Morgante, Michele; Sanchez, Juan-Pablo; Hanafey, Michael K; Tingey, Scott V; Chua, Nam-Hai

    2002-12-15

    The phytohormone abscisic acid (ABA) plays important regulatory roles in many plant developmental processes including seed dormancy, germination, growth, and stomatal movements. These physiological responses to ABA are in large part brought about by changes in gene expression. To study genome-wide ABA-responsive gene expression we applied massively parallel signature sequencing (MPSS) to samples from Arabidopsis thaliana wildtype (WT) and abi1-1 mutant seedlings. We identified 1354 genes that are either up- or downregulated following ABA treatment of WT seedlings. Among these ABA-responsive genes, many encode signal transduction components. In addition, we identified novel ABA-responsive gene families including those encoding ribosomal proteins and proteins involved in regulated proteolysis. In the ABA-insensitive mutant abi1-1, ABA regulation of about 84.5% and 6.9% of the identified genes was impaired or strongly diminished, respectively; however, 8.6% of the genes remained appropriately regulated. Compared to other methods of gene expression analysis, the high sensitivity and specificity of MPSS allowed us to identify a large number of ABA-responsive genes in WT Arabidopsis thaliana. The database given in our supplementary material (http://jcs.biologists.org/supplemental) provides researchers with the opportunity to rapidly assess whether genes of interest may be regulated by ABA. Regulation of the majority of the genes by ABA was impaired in the ABA-insensitive mutant abi1-1. However, a subset of genes continued to be appropriately regulated by ABA, which suggests the presence of at least two ABA signaling pathways, only one of which is blocked in abi1-1.

  11. Root and leaf abscisic acid concentration impact on gas exchange in tomato (Lycopersicon esculentum Mill plants subjected to partial root-zone drying

    Directory of Open Access Journals (Sweden)

    Maria Valerio

    2017-03-01

    Full Text Available Partial root-zone drying (PRD is a deficit irrigation technique with great potential for water saving. A split-root experiment was conducted on tomato in controlled environment in order to test the response of two long-time storage cultivars to PRD. Ponderosa tomato, a cultivar with yellow fruits, was compared to Giallo tondo di Auletta, a local cultivar from southern Campania (Italy. Plants were subjected to three irrigation treatments: plants receiving an amount of water equivalent to 100% of plant evapotranspiration (V100; plants in which 50% of the amount of water given to V100 was supplied (V50; and plants where one root compartment was irrigated at 50% of water requirements and the other compartment was allowed to dry, and thereafter every side was rewetted alternatively (PRD. The highest levels of leaf abscisic acid (ABA [on average equal to 104 ng g–1 fresh weight FW] were measured in PRD and V50, at 70 days after transplantation. Root ABA concentration in both PRD and V50 reached mean values of 149 ng g–1 FW. There were differences for the irrigation regime in root ABA biosynthesis and accumulation under partial root-zone drying and conventional deficit irrigation (V50. Assimilation rate, stomatal conductance and intercellular CO2 concentration decreased in relation to the irrigation regime by 22, 36 and 12%, respectively, in PRD, V50 and V100 at 50 days after transplantation. Ponderosa variety accumulated 20% more dry matter than Auletta and significant differences were observed in leaf area. In both PRD and V50 of the two varieties, it was possible to save on average 46% of water. Our results indicate that there is still space to optimise the PRD strategy, to further improve the cumulative physiological effects of the root-sourced signaling system.

  12. Arabidopsis Glutamate Receptor Homolog3.5 Modulates Cytosolic Ca2+ Level to Counteract Effect of Abscisic Acid in Seed Germination1[OPEN

    Science.gov (United States)

    Kong, Dongdong; Ju, Chuanli; Parihar, Aisha; Kim, So; Cho, Daeshik; Kwak, June M.

    2015-01-01

    Seed germination is a critical step in a plant’s life cycle that allows successful propagation and is therefore strictly controlled by endogenous and environmental signals. However, the molecular mechanisms underlying germination control remain elusive. Here, we report that the Arabidopsis (Arabidopsis thaliana) glutamate receptor homolog3.5 (AtGLR3.5) is predominantly expressed in germinating seeds and increases cytosolic Ca2+ concentration that counteracts the effect of abscisic acid (ABA) to promote germination. Repression of AtGLR3.5 impairs cytosolic Ca2+ concentration elevation, significantly delays germination, and enhances ABA sensitivity in seeds, whereas overexpression of AtGLR3.5 results in earlier germination and reduced seed sensitivity to ABA. Furthermore, we show that Ca2+ suppresses the expression of ABSCISIC ACID INSENSITIVE4 (ABI4), a key transcription factor involved in ABA response in seeds, and that ABI4 plays a fundamental role in modulation of Ca2+-dependent germination. Taken together, our results provide molecular genetic evidence that AtGLR3.5-mediated Ca2+ influx stimulates seed germination by antagonizing the inhibitory effects of ABA through suppression of ABI4. These findings establish, to our knowledge, a new and pivotal role of the plant glutamate receptor homolog and Ca2+ signaling in germination control and uncover the orchestrated modulation of the AtGLR3.5-mediated Ca2+ signal and ABA signaling via ABI4 to fine-tune the crucial developmental process, germination, in Arabidopsis. PMID:25681329

  13. Use of abscisic acid, mannitol and salt concentration decrease in the culture medium in the in vitro conservation of Ipomoea batatas

    Directory of Open Access Journals (Sweden)

    Angel Espinosa Reyes

    2002-01-01

    Full Text Available Nodal segment from in vitro plants of Jewel clone sweet potato were culture in the following culture medias: a Murashige and Skoog (1962 salts supplemented with abscisic acid (0.0, 1.0, 5.0 y 10.0 mg.l-1, b Murashige and Skoog (1962 salts supplemented with mannitol (0.0, 10.0 15.0 y 20.0 g.l-1 and c different Murashige and Skoog (1962 salts concentration (100, 75, 50 and 25% were used. Survival during conservation was high in all experiment. The 5.0 and 10.0 mg.l-1 abscisic acid strongly inhibited the plants growth. It was reached a decrease of growth when using mannitol in the culture medium. The media with 25% and 50% MS salts concentration caused a low of plants growth. When cultured in fresh culture medium it was achieved a high recovery ratio of conserved material. Key words: sweet potato, minimal growth, phyto resources, biodiversity

  14. Regulation of erucic acid accumulation in oilseed rape (Brassica napus L.) : effects of temperature and abscisic acid

    NARCIS (Netherlands)

    Wilmer, J.A.

    1997-01-01

    Vegetable oils are an important commodity world-wide with an annual production of about 70 million tonnes. Oilseed rape is one of the four major crops, providing about 10% of the total production. Quality of vegetable oils is determined by the fatty acid composition of the triacylglycerols

  15. Identification and characterization of the abscisic acid (ABA) receptor gene family and its expression in response to hormones in the rubber tree.

    Science.gov (United States)

    Guo, Dong; Zhou, Ying; Li, Hui-Liang; Zhu, Jia-Hong; Wang, Ying; Chen, Xiong-Ting; Peng, Shi-Qing

    2017-03-23

    Abscisic acid (ABA) is an essential phytohormone involved in diverse physiological processes. Although genome-wide analyses of the ABA receptor PYR/PYL/RCAR (PYL) protein/gene family have been performed in certain plant species, little is known about the ABA receptor protein/gene family in the rubber tree (Hevea brasiliensis). In this study, we identified 14 ABA receptor PYL proteins/genes (designated HbPYL1 through HbPYL14) in the most recent rubber tree genome. A phylogenetic tree was constructed, which demonstrated that HbPYLs can be divided into three subfamilies that correlate well with the corresponding Arabidopsis subfamilies. Eight HbPYLs are highly expressed in laticifers. Five of the eight genes are simultaneously regulated by ABA, jasmonic acid (JA) and ethylene (ET). The identification and characterization of HbPYLs should enable us to further understand the role of ABA signal in the rubber tree.

  16. Abscisic Acid Promotes Susceptibility to the Rice Leaf Blight Pathogen Xanthomonas oryzae pv oryzae by Suppressing Salicylic Acid-Mediated Defenses.

    Directory of Open Access Journals (Sweden)

    Jing Xu

    Full Text Available The plant hormone abscisic acid (ABA is involved in a wide variety of plant processes, including the initiation of stress-adaptive responses to various environmental cues. Recently, ABA also emerged as a central factor in the regulation and integration of plant immune responses, although little is known about the underlying mechanisms. Aiming to advance our understanding of ABA-modulated disease resistance, we have analyzed the impact, dynamics and interrelationship of ABA and the classic defense hormone salicylic acid (SA during progression of rice infection by the leaf blight pathogen Xanthomonas oryzae pv. oryzae (Xoo. Consistent with ABA negatively regulating resistance to Xoo, we found that exogenously administered ABA renders rice hypersusceptible to infection, whereas chemical and genetic disruption of ABA biosynthesis and signaling, respectively, led to enhanced Xoo resistance. In addition, we found successful Xoo infection to be associated with extensive reprogramming of ABA biosynthesis and response genes, suggesting that ABA functions as a virulence factor for Xoo. Interestingly, several lines of evidence indicate that this immune-suppressive effect of ABA is due at least in part to suppression of SA-mediated defenses that normally serve to limit pathogen growth. Resistance induced by the ABA biosynthesis inhibitor fluridone, however, appears to operate in a SA-independent manner and is likely due to induction of non-specific physiological stress. Collectively, our findings favor a scenario whereby virulent Xoo hijacks the rice ABA machinery to cause disease and highlight the importance of ABA and its crosstalk with SA in shaping the outcome of rice-Xoo interactions.

  17. AtPP2CG1, a protein phosphatase 2C, positively regulates salt tolerance of Arabidopsis in abscisic acid-dependent manner

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xin, E-mail: fangfei6073@126.com [Plant Bioengineering Laboratory, Northeast Agricultural University, Harbin 150030 (China); Zhu, Yanming, E-mail: ymzhu2001@neau.edu.cn [Plant Bioengineering Laboratory, Northeast Agricultural University, Harbin 150030 (China); Zhai, Hong, E-mail: Zhai.h@neigaehrb.ac.cn [Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Harbin 150040 (China); Cai, Hua, E-mail: small-big@sohu.com [Plant Bioengineering Laboratory, Northeast Agricultural University, Harbin 150030 (China); Ji, Wei, E-mail: iwei_j@hotmail.com [Plant Bioengineering Laboratory, Northeast Agricultural University, Harbin 150030 (China); Luo, Xiao, E-mail: luoxiao2010@yahoo.cn [Plant Bioengineering Laboratory, Northeast Agricultural University, Harbin 150030 (China); Li, Jing, E-mail: lijing@neau.edu.cn [Plant Secondary Metabolism Laboratory, Northeast Agricultural University, Harbin 150030 (China); Bai, Xi, E-mail: baixi@neau.edu.cn [Plant Bioengineering Laboratory, Northeast Agricultural University, Harbin 150030 (China)

    2012-06-15

    Highlights: Black-Right-Pointing-Pointer AtPP2CG1 positively regulates salt tolerance in ABA-dependent manner. Black-Right-Pointing-Pointer AtPP2CG1 up-regulates the expression of marker genes in different pathways. Black-Right-Pointing-Pointer AtPP2CG1 expresses in the vascular system and trichomes of Arabidopsis. -- Abstract: AtPP2CG1 (Arabidopsis thaliana protein phosphatase 2C G Group 1) was predicted as an abiotic stress candidate gene by bioinformatic analysis in our previous study. The gene encodes a putative protein phosphatase 2C that belongs to Group G of PP2C. There is no report of Group G genes involved in abiotic stress so far. Real-time RT-PCR analysis showed that AtPP2CG1 expression was induced by salt, drought, and abscisic acid (ABA) treatment. The expression levels of AtPP2CG1 in the ABA synthesis-deficient mutant abi2-3 were much lower than that in WT plants under salt stress suggesting that the expression of AtPP2CG1 acts in an ABA-dependent manner. Over-expression of AtPP2CG1 led to enhanced salt tolerance, whereas its loss of function caused decreased salt tolerance. These results indicate that AtPP2CG1 positively regulates salt stress in an ABA-dependent manner. Under salt treatment, AtPP2CG1 up-regulated the expression levels of stress-responsive genes, including RD29A, RD29B, DREB2A and KIN1. GUS activity was detected in roots, leaves, stems, flower, and trichomes of AtPP2CG1 promoter-GUS transgenic plants. AtPP2CG1 protein was localized in nucleus and cytoplasm via AtPP2CG1:eGFP and YFP:AtPP2CG1 fusion approaches.

  18. An ultrahigh-performance liquid chromatography method with electrospray ionization tandem mass spectrometry for simultaneous quantification of five phytohormones in medicinal plant Glycyrrhiza uralensis under abscisic acid stress.

    Science.gov (United States)

    Xiang, Yu; Song, Xiaona; Qiao, Jing; Zang, Yimei; Li, Yanpeng; Liu, Yong; Liu, Chunsheng

    2015-07-01

    An efficient simplified method was developed to determine multiple classes of phytohormones simultaneously in the medicinal plant Glycyrrhiza uralensis. Ultrahigh-performance liquid chromatography electrospray ionization tandem mass spectrometry (UPLC/ESI-MS/MS) with multiple reaction monitoring (MRM) in negative mode was used for quantification. The five studied phytohormones are gibberellic acid (GA3), abscisic acid (ABA), jasmonic acid (JA), indole-3-acetic acid, and salicylic acid (SA). Only 100 mg of fresh leaves was needed, with one purification step based on C18 solid-phase extraction. Cinnamic acid was chosen as the internal standard instead of isotope-labeled internal standards. Under the optimized conditions, the five phytohormones with internal standard were separated within 4 min, with good linearities and high sensitivity. The validated method was applied to monitor the spatial and temporal changes of the five phytohormones in G. uralensis under ABA stress. The levels of GA3, ABA, JA, and SA in leaves of G. uralensis were increased at different times and with different tendencies in the reported stress mode. These changes in phytohormone levels are discussed in the context of a possible feedback regulation mechanism. Understanding this mechanism will provide a good chance of revealing the mutual interplay between different biosynthetic routes, which could further help elucidate the mechanisms of effective composition accumulation in medicinal plants.

  19. Up-regulating the abscisic acid inactivation gene ZmABA8ox1b contributes to seed germination heterosis by promoting cell expansion.

    Science.gov (United States)

    Li, Yangyang; Wang, Cheng; Liu, Xinye; Song, Jian; Li, Hongjian; Sui, Zhipeng; Zhang, Ming; Fang, Shuang; Chu, Jinfang; Xin, Mingming; Xie, Chaojie; Zhang, Yirong; Sun, Qixin; Ni, Zhongfu

    2016-04-01

    Heterosis has been widely used in agriculture, but the underlying molecular principles are still largely unknown. During seed germination, we observed that maize (Zea mays) hybrid B73/Mo17 was less sensitive than its parental inbred lines to exogenous abscisic acid (ABA), and endogenous ABA content in hybrid embryos decreased more rapidly than in the parental inbred lines. ZmABA8ox1b, an ABA inactivation gene, was consistently more highly up-regulated in hybrid B73/Mo17 than in its parental inbred lines at early stages of seed germination. Moreover, ectopic expression of ZmABA8ox1b obviously promoted seed germination in Arabidopsis Remarkably, microscopic observation revealed that cell expansion played a major role in the ABA-mediated maize seed germination heterosis, which could be attributed to the altered expression of cell wall-related genes. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  20. Acid Mine Drainage Treatment

    National Research Council Canada - National Science Library

    Fripp, Jon

    2000-01-01

    .... Acid mine drainage (AMD) can have severe impacts to aquatic resources, can stunt terrestrial plant growth and harm wetlands, contaminate groundwater, raise water treatment costs, and damage concrete and metal structures...

  1. A mutation in the Arabidopsis HYL1 gene encoding a dsRNA binding protein affects responses to abscisic acid, auxin, and cytokinin

    Science.gov (United States)

    Lu, C.; Fedoroff, N.

    2000-01-01

    Both physiological and genetic evidence indicate interconnections among plant responses to different hormones. We describe a pleiotropic recessive Arabidopsis transposon insertion mutation, designated hyponastic leaves (hyl1), that alters the plant's responses to several hormones. The mutant is characterized by shorter stature, delayed flowering, leaf hyponasty, reduced fertility, decreased rate of root growth, and an altered root gravitropic response. It also exhibits less sensitivity to auxin and cytokinin and hypersensitivity to abscisic acid (ABA). The auxin transport inhibitor 2,3,5-triiodobenzoic acid normalizes the mutant phenotype somewhat, whereas another auxin transport inhibitor, N-(1-naph-thyl)phthalamic acid, exacerbates the phenotype. The gene, designated HYL1, encodes a 419-amino acid protein that contains two double-stranded RNA (dsRNA) binding motifs, a nuclear localization motif, and a C-terminal repeat structure suggestive of a protein-protein interaction domain. We present evidence that the HYL1 gene is ABA-regulated and encodes a nuclear dsRNA binding protein. We hypothesize that the HYL1 protein is a regulatory protein functioning at the transcriptional or post-transcriptional level.

  2. Overexpression of an Arabidopsis cysteine-rich receptor-like protein kinase, CRK5, enhances abscisic acid sensitivity and confers drought tolerance

    Science.gov (United States)

    Lu, Kai; Liang, Shan; Wu, Zhen; Bi, Chao; Yu, Yong-Tao; Wang, Xiao-Fang; Zhang, Da-Peng

    2016-01-01

    Receptor-like kinases (RLKs) have been reported to regulate many developmental and defense process, but only a few members have been functionally characterized. In the present study, our observations suggest that one of the RLKs, a membrane-localized cysteine-rich receptor-like protein kinase, CRK5, is involved in abscisic acid (ABA) signaling in Arabidopsis thaliana. Overexpression of CRK5 increases ABA sensitivity in ABA-induced early seedling growth arrest and promotion of stomatal closure and inhibition of stomatal opening. Interestingly, and importantly, overexpression of CRK5 enhances plant drought tolerance without affecting plant growth at the mature stages and plant productivity. Transgenic lines overexpressing a mutated form of CRK5, CRK5 K372E with the change of the 372nd conserved amino acid residue from lysine to glutamic acid in its kinase domain, result in wild-type ABA and drought responses, supporting the role of CRK5 in ABA signaling. The loss-of-function mutation of the CRK5 gene does not affect the ABA response, while overexpression of two homologs of CRK5, CRK4 and CRK19, confers ABA responses, suggesting that these CRK members function redundantly. We further showed that WRKY18, WRKY40 and WRKY60 transcription factors repress the expression of CRK5, and that CRK5 likely functions upstream of ABI2 in ABA signaling. These findings help in understanding the complex ABA signaling network. PMID:27406784

  3. Transcriptional regulation of abscisic acid signal core components during cucumber seed germination and under Cu²⁺, Zn²⁺, NaCl and simulated acid rain stresses.

    Science.gov (United States)

    Wang, Yanping; Wang, Ya; Kai, Wenbin; Zhao, Bo; Chen, Pei; Sun, Liang; Ji, Kai; Li, Qian; Dai, Shengjie; Sun, Yufei; Wang, Yidong; Pei, Yuelin; Leng, Ping

    2014-03-01

    Abscisic acid (ABA) is an important phytohormone that regulates lots of physiological and biochemical processes in plant life cycle, especially in seed germination and stress responses. For exploring the transcriptional regulation of ABA signal transduction during cucumber (Cucumis sativus L.) seed germination and under Cu(2+), Zn(2+), NaCl and simulated acid rain stresses, nine CsPYLs, three group A CsPP2Cs and two subclass III CsSnRK2s were identified from cucumber genome, which respectively showed high sequence similarities and highly conserved domains with homologous genes in Arabidopsis. Based on Real-time PCR analysis, most of the tested genes' expression decreased during cucumber seed germination, which was in accordance with the ABA level variation. In addition, according to the absolute expression, CsPYL1, CsPYL3, CsPP2C5, CsABI1, CsSnRK2.3 and CsSnRK2.4 were highly expressed, indicating that they may play more important roles in ABA signaling during cucumber seed germination. Moreover, most of these highly expressed genes, except CsPYL3, were up-regulated by ABA treatment. Meanwhile, most of the tested genes' expression dramatically changed at the initial water uptake phase, indicating that this period may be critical in the regulation of ABA on seed germination. Under Cu(2+), Zn(2+), NaCl and simulated acid rain stresses, cucumber seed germination percentage decreased and ABA content increased. Meanwhile, the expression of ABA signal transduction core components genes showed specific response to a particular stress and was not always consist with ABA variation. Generally, the expression of CsPYL1, CsPYL3, CsABI1, CsSnRK2.3 and CsSnRK2.4 was sensitive to 120 mM NaCl and 0.5 mM Cu(2+) treatments. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  4. The ribosomal small-subunit protein S28 gene from Helianthus annuus (Asteraceae) is down-regulated in response to drought, high salinity, and abscisic acid.

    Science.gov (United States)

    Liu, Xianan; Baird, W Vance

    2003-04-01

    A partial cDNA for the ribosomal S28 gene from sunflower was initially cloned and identified to be down-regulated by high salinity, using differential display reverse transcriptase-polymerase chain reaction (PCR). Using this sequence, a 502-base pair (bp) full-length cDNA was cloned by rapid amplification of cDNA ends. This cDNA (designated Ha-RPS28) encodes a protein component of the small subunit of cytoplasmic ribosomes. The predicted 65 amino acid residue sequence of Ha-RPS28, with an estimated molecular mass of 7.5 kD, has 92, 89, and 86% identity with the S28 ribosomal proteins from peach, maize, and Arabidopsis, respectively. Ha-RPS28 was expressed in all organs examined, and the highest level was detected in fully expanded leaves. Furthermore, expression of Ha-RPS28 was down-regulated in both seedling roots and shoots in response to drought, high salinity, or abscisic acid.

  5. Development and Validation of a Reversed-Phase Liquid Chromatography Method for the Simultaneous Determination of Indole-3-Acetic Acid, Indole-3-Pyruvic Acid, and Abscisic Acid in Barley (Hordeum vulgare L.).

    Science.gov (United States)

    Nakurte, Ilva; Keisa, Anete; Rostoks, Nils

    2012-01-01

    A simple, sensitive, precise, and specific reverse HPLC method was developed and validated for the determination of plant hormones in barley (Hordeum vulgare L.). The method includes extraction in aqueous organic solvent followed by solid-phase extraction, sample evaporation, and reversed-phase HPLC analysis in a general purpose UV-visible (abscisic acid (ABA)) and fluorescence detection (indole-3-acetic acid (IAA) and indole-3-pyruvic acid (IPA)), high-performance liquid chromatography system. The separation was carried out on Zorbax Eclipse XDB C8 column (150  ×  4.6  mm I.D) with a mobile phase composed of methanol and 1% acetic acid (60 : 40 v/v) in isocratic mode at a flow rate of 1 ml min(-1). The detection was monitored at 270 nm (ABA) and at 282 nm (Ex) and 360 nm (Em) (IAA, IPA). The developed method was validated in terms of accuracy, precision, linearity, limit of detection, limit of quantification, and robustness. The determined validation parameters are in the commonly acceptable ranges for that kind of analysis.

  6. Antagonistic roles of abscisic acid and cytokinin during response to nitrogen depletion in oleaginous microalga Nannochloropsis oceanica expand the evolutionary breadth of phytohormone function.

    Science.gov (United States)

    Lu, Yandu; Tarkowská, Danuše; Turečková, Veronika; Luo, Tingwei; Xin, Yi; Li, Jing; Wang, Qintao; Jiao, Nianzhi; Strnad, Miroslav; Xu, Jian

    2014-10-01

    The origin of phytohormones is poorly understood, and their physiological roles in microalgae remain elusive. Genome comparison of photosynthetic autotrophic eukaryotes has revealed that the biosynthetic pathways of abscisic acid (ABA) and cytokinins (CKs) emerged in unicellular algae. While ABA and CK degradation mechanisms emerged broadly in algal lineages, complete vascular plant-type conjugation pathways emerged prior to the rise of Streptophyta. In microalgae, a complete set of proteins from the canonical ABA and CK sensing and signaling pathways is not essential, but individual components are present, suggesting stepwise recruitment of phytohormone signaling components. In the oleaginous eustigmatophyte Nannochloropsis oceanica IMET1, UHPLC-MS/MS detected a wide array of plant hormones, despite a phytohormone profile that is very distinct from that of flowering plants. Time-series transcriptional analysis during nitrogen depletion revealed activation of the ABA biosynthetic pathway and antagonistic transcription of CK biosynthetic genes. Correspondingly, the ABA level increases while the dominant bioactive CK forms decrease. Moreover, exogenous CKs stimulate cell-cycle progression while exogenous ABA acts as both an algal growth repressor and a positive regulator in response to stresses. The presence of such functional flowering plant-like phytohormone signaling systems in Nannochloropsis sp. suggests a much earlier origin of phytohormone biosynthesis and degradation than previously believed, and supports the presence in microalgae of as yet unknown conjugation and sensing/signaling systems that may be exploited for microalgal feedstock development. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.

  7. Persistent negative temperature response of mesophyll conductance in red raspberry (Rubus idaeus L.) leaves under both high and low vapour pressure deficits: a role for abscisic acid?

    Science.gov (United States)

    Qiu, Changpeng; Ethier, Gilbert; Pepin, Steeve; Dubé, Pascal; Desjardins, Yves; Gosselin, André

    2017-09-01

    The temperature dependence of mesophyll conductance (g m ) was measured in well-watered red raspberry (Rubus idaeus L.) plants acclimated to leaf-to-air vapour pressure deficit (VPDL) daytime differentials of contrasting amplitude, keeping a fixed diurnal leaf temperature (T leaf ) rise from 20 to 35 °C. Contrary to the great majority of g m temperature responses published to date, we found a pronounced reduction of g m with increasing T leaf irrespective of leaf chamber O 2 level and diurnal VPDL regime. Leaf hydraulic conductance was greatly enhanced during the warmer afternoon periods under both low (0.75 to 1.5 kPa) and high (0.75 to 3.5 kPa) diurnal VPDL regimes, unlike stomatal conductance (g s ), which decreased in the afternoon. Consequently, the leaf water status remained largely isohydric throughout the day, and therefore cannot be evoked to explain the diurnal decrease of g m . However, the concerted diurnal reductions of g m and g s were well correlated with increases in leaf abscisic acid (ABA) content, thus suggesting that ABA can induce a significant depression of g m under favourable leaf water status. Our results challenge the view that the temperature dependence of g m can be explained solely from dynamic leaf anatomical adjustments and/or from the known thermodynamic properties of aqueous solutions and lipid membranes.​. © 2017 John Wiley & Sons Ltd.

  8. Gladiolus hybridus ABSCISIC ACID INSENSITIVE 5 (GhABI5) is an important transcription factor in ABA signaling that can enhance Gladiolus corm dormancy and Arabidopsis seed dormancy

    Science.gov (United States)

    Wu, Jian; Seng, Shanshan; Sui, Juanjuan; Vonapartis, Eliana; Luo, Xian; Gong, Benhe; Liu, Chen; Wu, Chenyu; Liu, Chao; Zhang, Fengqin; He, Junna; Yi, Mingfang

    2015-01-01

    The phytohormone abscisic acid (ABA) regulates plant development and is crucial for abiotic stress response. In this study, cold storage contributes to reducing endogenous ABA content, resulting in dormancy breaking of Gladiolus. The ABA inhibitor fluridone also promotes germination, suggesting that ABA is an important hormone that regulates corm dormancy. Here, we report the identification and functional characterization of the Gladiolus ABI5 homolog (GhABI5), which is a basic leucine zipper motif transcriptional factor (TF). GhABI5 is expressed in dormant vegetative organs (corm, cormel, and stolon) as well as in reproductive organs (stamen), and it is up-regulated by ABA or drought. Complementation analysis reveals that GhABI5 rescues the ABA insensitivity of abi5-3 during seed germination and induces the expression of downstream ABA response genes in Arabidopsis thaliana (EM1, EM6, and RD29B). Down-regulation of GhABI5 in dormant cormels via virus induced gene silence promotes sprouting and reduces the expression of downstream genes (GhLEA and GhRD29B). The results of this study reveal that GhABI5 regulates bud dormancy (vegetative organ) in Gladiolus in addition to its well-studied function in Arabidopsis seeds (reproductive organ). PMID:26579187

  9. Chloride-inducible transient apoplastic alkalinizations induce stomata closure by controlling abscisic acid distribution between leaf apoplast and guard cells in salt-stressed Vicia faba.

    Science.gov (United States)

    Geilfus, Christoph-Martin; Mithöfer, Axel; Ludwig-Müller, Jutta; Zörb, Christian; Muehling, Karl H

    2015-11-01

    Chloride stress causes the leaf apoplast transiently to alkalize, an event that is presumed to contribute to the ability of plants to adapt to saline conditions. However, the initiation of coordinated processes downstream of the alkalinization is unknown. We hypothesize that chloride-inducible pH dynamics are a key chemical feature modulating the compartmental distribution of abscisic acid (ABA) and, as a consequence, affecting stomata aperture. Apoplastic pH and stomata aperture dynamics in intact Vicia faba leaves were monitored by microscopy-based ratio imaging and porometric measurements of stomatal conductance. ABA concentrations in leaf apoplast and guard cells were compared with pH dynamics by gas-chromatography-mass-spectrometry (GC-MS) and liquid-chromatography-tandem-mass spectrometry (LC-MS/MS). Results demonstrate that, upon chloride addition to roots, an alkalizing factor that initiates the pH dynamic propagates from root to leaf in a way similar to xylem-distributed water. In leaves, it induces a systemic transient apoplastic alkalinization that causes apoplastic ABA concentration to increase, followed by an elevation of endogenous guard cell ABA. We conclude that the transient alkalinization, which is a remote effect of chloride stress, modulates the compartmental distribution of ABA between the leaf apoplast and the guard cells and, in this way, is instrumental in inducing stomata closure during the beginning of salinity. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  10. Resistance to Botrytis cinerea in sitiens, an abscisic acid-deficient tomato mutant, involves timely production of hydrogen peroxide and cell wall modifications in the epidermis.

    Science.gov (United States)

    Asselbergh, Bob; Curvers, Katrien; Franca, Soraya C; Audenaert, Kris; Vuylsteke, Marnik; Van Breusegem, Frank; Höfte, Monica

    2007-08-01

    Plant defense mechanisms against necrotrophic pathogens, such as Botrytis cinerea, are considered to be complex and to differ from those that are effective against biotrophs. In the abscisic acid-deficient sitiens tomato (Solanum lycopersicum) mutant, which is highly resistant to B. cinerea, accumulation of hydrogen peroxide (H(2)O(2)) was earlier and stronger than in the susceptible wild type at the site of infection. In sitiens, H(2)O(2) accumulation was observed from 4 h postinoculation (hpi), specifically in the leaf epidermal cell walls, where it caused modification by protein cross-linking and incorporation of phenolic compounds. In wild-type tomato plants, H(2)O(2) started to accumulate 24 hpi in the mesophyll layer and was associated with spreading cell death. Transcript-profiling analysis using TOM1 microarrays revealed that defense-related transcript accumulation prior to infection was higher in sitiens than in wild type. Moreover, further elevation of sitiens defense gene expression was stronger than in wild type 8 hpi both in number of genes and in their expression levels and confirmed a role for cell wall modification in the resistant reaction. Although, in general, plant defense-related reactive oxygen species formation facilitates necrotrophic colonization, these data indicate that timely hyperinduction of H(2)O(2)-dependent defenses in the epidermal cell wall can effectively block early development of B. cinerea.

  11. Overexpression of an Arabidopsis cysteine-rich receptor-like protein kinase, CRK5, enhances abscisic acid sensitivity and confers drought tolerance.

    Science.gov (United States)

    Lu, Kai; Liang, Shan; Wu, Zhen; Bi, Chao; Yu, Yong-Tao; Wang, Xiao-Fang; Zhang, Da-Peng

    2016-09-01

    Receptor-like kinases (RLKs) have been reported to regulate many developmental and defense process, but only a few members have been functionally characterized. In the present study, our observations suggest that one of the RLKs, a membrane-localized cysteine-rich receptor-like protein kinase, CRK5, is involved in abscisic acid (ABA) signaling in Arabidopsis thaliana Overexpression of CRK5 increases ABA sensitivity in ABA-induced early seedling growth arrest and promotion of stomatal closure and inhibition of stomatal opening. Interestingly, and importantly, overexpression of CRK5 enhances plant drought tolerance without affecting plant growth at the mature stages and plant productivity. Transgenic lines overexpressing a mutated form of CRK5, CRK5 (K372E) with the change of the 372nd conserved amino acid residue from lysine to glutamic acid in its kinase domain, result in wild-type ABA and drought responses, supporting the role of CRK5 in ABA signaling. The loss-of-function mutation of the CRK5 gene does not affect the ABA response, while overexpression of two homologs of CRK5, CRK4 and CRK19, confers ABA responses, suggesting that these CRK members function redundantly. We further showed that WRKY18, WRKY40 and WRKY60 transcription factors repress the expression of CRK5, and that CRK5 likely functions upstream of ABI2 in ABA signaling. These findings help in understanding the complex ABA signaling network. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  12. Overexpression of a Protein Phosphatase 2C from Beech Seeds in Arabidopsis Shows Phenotypes Related to Abscisic Acid Responses and Gibberellin Biosynthesis1

    Science.gov (United States)

    Reyes, David; Rodríguez, Dolores; González-García, Mary Paz; Lorenzo, Oscar; Nicolás, Gregorio; García-Martínez, José Luis; Nicolás, Carlos

    2006-01-01

    A functional abscisic acid (ABA)-induced protein phosphatase type 2C (PP2C) was previously isolated from beech (Fagus sylvatica) seeds (FsPP2C2). Because transgenic work is not possible in beech, in this study we overexpressed this gene in Arabidopsis (Arabidopsis thaliana) to provide genetic evidence on FsPP2C2 function in seed dormancy and other plant responses. In contrast with other PP2Cs described so far, constitutive expression of FsPP2C2 in Arabidopsis, under the cauliflower mosaic virus 35S promoter, produced enhanced sensitivity to ABA and abiotic stress in seeds and vegetative tissues, dwarf phenotype, and delayed flowering, and all these effects were reversed by gibberellic acid application. The levels of active gibberellins (GAs) were reduced in 35S:FsPP2C2 plants, although transcript levels of AtGA20ox1 and AtGA3ox1 increased, probably as a result of negative feedback regulation, whereas the expression of GASA1 was induced by GAs. Additionally, FsPP2C2-overexpressing plants showed a strong induction of the Responsive to ABA 18 (RAB18) gene. Interestingly, FsPP2C2 contains two nuclear targeting sequences, and transient expression assays revealed that ABA directed this protein to the nucleus. Whereas other plant PP2Cs have been shown to act as negative regulators, our results support the hypothesis that FsPP2C2 is a positive regulator of ABA. Moreover, our results indicate the existence of potential cross-talk between ABA signaling and GA biosynthesis. PMID:16815952

  13. Age-related mechanism and its relationship with secondary metabolism and abscisic acid in Aristotelia chilensis plants subjected to drought stress.

    Science.gov (United States)

    González-Villagra, Jorge; Rodrigues-Salvador, Acácio; Nunes-Nesi, Adriano; Cohen, Jerry D; Reyes-Díaz, Marjorie M

    2018-03-01

    Drought stress is the most important stress factor for plants, being the main cause of agricultural crop loss in the world. Plants have developed complex mechanisms for preventing water loss and oxidative stress such as synthesis of abscisic acid (ABA) and non-enzymatic antioxidant compounds such as anthocyanins, which might help plants to cope with abiotic stress as antioxidants and for scavenging reactive oxygen species. A. chilensis (Mol.) is a pioneer species, colonizing and growing on stressed and disturbed environments. In this research, an integrated analysis of secondary metabolism in Aristotelia chilensis was done to relate ABA effects on anthocyanins biosynthesis, by comparing between young and fully-expanded leaves under drought stress. Plants were subjected to drought stress for 20 days, and physiological, biochemical, and molecular analyses were performed. The relative growth rate and plant water status were reduced in stressed plants, with young leaves significantly more affected than fully-expanded leaves beginning from the 5th day of drought stress. A. chilensis plants increased their ABA and total anthocyanin content and showed upregulation of gene expression when they were subjected to severe drought (day 20), with these effects being higher in fully-expanded leaves. Multivariate analysis indicated a significant positive correlation between transcript levels for NCED1 (9-cis-epoxycarotenoid dioxygenase) and UFGT (UDP glucose: flavonoid-3-O-glucosyltransferase) with ABA and total anthocyanin, respectively. Thus, this research provides a more comprehensive analysis of the mechanisms that allow plants to cope with drought stress. This is highlighted by the differences between young and fully-expanded leaves, showing different sensibility to stress due to their ability to synthesize anthocyanins. In addition, this ability to synthesize different and high amounts of anthocyanins could be related to higher NCED1 and MYB expression and ABA levels

  14. Evaluating the involvement and interaction of abscisic acid and miRNA156 in the induction of anthocyanin biosynthesis in drought-stressed plants.

    Science.gov (United States)

    González-Villagra, Jorge; Kurepin, Leonid V; Reyes-Díaz, Marjorie M

    2017-08-01

    ABA is involved in anthocyanin synthesis through the regulation of microRNA156, augmenting the level of expression of anthocyanin synthesis-related genes and, therefore, increasing anthocyanin level. Drought stress is the main cause of agricultural crop loss in the world. However, plants have developed mechanisms that allow them to tolerate drought stress conditions. At cellular level, drought stress induces changes in metabolite accumulation, including increases in anthocyanin levels due to upregulation of the anthocyanin biosynthetic pathway. Recent studies suggest that the higher anthocyanin content observed under drought stress conditions could be a consequence of a rise in the abscisic acid (ABA) concentration. This plant hormone crosses the plasma membrane by specific transporters, and it is recognized at the cytosolic level by receptors known as pyrabactin resistance (PYR)/regulatory component of ABA receptors (PYR/RCARs) that regulate downstream components. In this review, we discuss the hypothesis regarding the involvement of ABA in the regulation of microRNA156 (miRNA156), which is upregulated as part of dehydration stress responsiveness in different species. The miRNA156 upregulation produces a greater level of anthocyanin gene expression, forming the multienzyme complex that will synthesize an increased level of anthocyanins at the cytosolic face of the rough endoplasmic reticulum (RER). After synthesis, anthocyanins are transported from the RER to the vacuole by two possible models of transport: (1) membrane vesicle-mediated transport, or (2) membrane transporter-mediated transport. Thus, the aim was to analyze the recent findings on synthesis, transport and the possible mechanism by which ABA could increase anthocyanin synthesis under drought stress conditions potentially throughout microRNA156 (miRNA156).

  15. Roles of arabidopsis WRKY18, WRKY40 and WRKY60 transcription factors in plant responses to abscisic acid and abiotic stress.

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    Chen, Han; Lai, Zhibing; Shi, Junwei; Xiao, Yong; Chen, Zhixiang; Xu, Xinping

    2010-12-19

    WRKY transcription factors are involved in plant responses to both biotic and abiotic stresses. Arabidopsis WRKY18, WRKY40, and WRKY60 transcription factors interact both physically and functionally in plant defense responses. However, their role in plant abiotic stress response has not been directly analyzed. We report that the three WRKYs are involved in plant responses to abscisic acid (ABA) and abiotic stress. Through analysis of single, double, and triple mutants and overexpression lines for the WRKY genes, we have shown that WRKY18 and WRKY60 have a positive effect on plant ABA sensitivity for inhibition of seed germination and root growth. The same two WRKY genes also enhance plant sensitivity to salt and osmotic stress. WRKY40, on the other hand, antagonizes WRKY18 and WRKY60 in the effect on plant sensitivity to ABA and abiotic stress in germination and growth assays. Both WRKY18 and WRKY40 are rapidly induced by ABA, while induction of WRKY60 by ABA is delayed. ABA-inducible expression of WRKY60 is almost completely abolished in the wrky18 and wrky40 mutants. WRKY18 and WRKY40 recognize a cluster of W-box sequences in the WRKY60 promoter and activate WRKY60 expression in protoplasts. Thus, WRKY60 might be a direct target gene of WRKY18 and WRKY40 in ABA signaling. Using a stable transgenic reporter/effector system, we have shown that both WRKY18 and WRKY60 act as weak transcriptional activators while WRKY40 is a transcriptional repressor in plant cells. We propose that the three related WRKY transcription factors form a highly interacting regulatory network that modulates gene expression in both plant defense and stress responses by acting as either transcription activator or repressor.

  16. Roles of arabidopsis WRKY18, WRKY40 and WRKY60 transcription factors in plant responses to abscisic acid and abiotic stress

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    Chen Zhixiang

    2010-12-01

    Full Text Available Abstract Background WRKY transcription factors are involved in plant responses to both biotic and abiotic stresses. Arabidopsis WRKY18, WRKY40, and WRKY60 transcription factors interact both physically and functionally in plant defense responses. However, their role in plant abiotic stress response has not been directly analyzed. Results We report that the three WRKYs are involved in plant responses to abscisic acid (ABA and abiotic stress. Through analysis of single, double, and triple mutants and overexpression lines for the WRKY genes, we have shown that WRKY18 and WRKY60 have a positive effect on plant ABA sensitivity for inhibition of seed germination and root growth. The same two WRKY genes also enhance plant sensitivity to salt and osmotic stress. WRKY40, on the other hand, antagonizes WRKY18 and WRKY60 in the effect on plant sensitivity to ABA and abiotic stress in germination and growth assays. Both WRKY18 and WRKY40 are rapidly induced by ABA, while induction of WRKY60 by ABA is delayed. ABA-inducible expression of WRKY60 is almost completely abolished in the wrky18 and wrky40 mutants. WRKY18 and WRKY40 recognize a cluster of W-box sequences in the WRKY60 promoter and activate WRKY60 expression in protoplasts. Thus, WRKY60 might be a direct target gene of WRKY18 and WRKY40 in ABA signaling. Using a stable transgenic reporter/effector system, we have shown that both WRKY18 and WRKY60 act as weak transcriptional activators while WRKY40 is a transcriptional repressor in plant cells. Conclusions We propose that the three related WRKY transcription factors form a highly interacting regulatory network that modulates gene expression in both plant defense and stress responses by acting as either transcription activator or repressor.

  17. Gene Expression and Metabolite Profiling of Developing Highbush Blueberry Fruit Indicates Transcriptional Regulation of Flavonoid Metabolism and Activation of Abscisic Acid Metabolism1[W][OA

    Science.gov (United States)

    Zifkin, Michael; Jin, Alena; Ozga, Jocelyn A.; Zaharia, L. Irina; Schernthaner, Johann P.; Gesell, Andreas; Abrams, Suzanne R.; Kennedy, James A.; Constabel, C. Peter

    2012-01-01

    Highbush blueberry (Vaccinium corymbosum) fruits contain substantial quantities of flavonoids, which are implicated in a wide range of health benefits. Although the flavonoid constituents of ripe blueberries are known, the molecular genetics underlying their biosynthesis, localization, and changes that occur during development have not been investigated. Two expressed sequence tag libraries from ripening blueberry fruit were constructed as a resource for gene identification and quantitative real-time reverse transcription-polymerase chain reaction primer design. Gene expression profiling by quantitative real-time reverse transcription-polymerase chain reaction showed that flavonoid biosynthetic transcript abundance followed a tightly regulated biphasic pattern, and transcript profiles were consistent with the abundance of the three major classes of flavonoids. Proanthocyanidins (PAs) and corresponding biosynthetic transcripts encoding anthocyanidin reductase and leucoanthocyanidin reductase were most concentrated in young fruit and localized predominantly to the inner fruit tissue containing the seeds and placentae. Mean PA polymer length was seven to 8.5 subunits, linked predominantly via B-type linkages, and was relatively constant throughout development. Flavonol accumulation and localization patterns were similar to those of the PAs, and the B-ring hydroxylation pattern of both was correlated with flavonoid-3′-hydroxylase transcript abundance. By contrast, anthocyanins accumulated late in maturation, which coincided with a peak in flavonoid-3-O-glycosyltransferase and flavonoid-3′5′-hydroxylase transcripts. Transcripts of VcMYBPA1, which likely encodes an R2R3-MYB transcriptional regulator of PA synthesis, were prominent in both phases of development. Furthermore, the initiation of ripening was accompanied by a substantial rise in abscisic acid, a growth regulator that may be an important component of the ripening process and contribute to the regulation

  18. Storage behavior and changes in concentrations of abscisic acid and gibberellins during dormancy break and germination in seeds of Phellodendron amurense var. wilsonii (Rutaceae).

    Science.gov (United States)

    Chen, Shun-Ying; Chien, Ching-Te; Baskin, Jerry M; Baskin, Carol C

    2010-02-01

    The medicinal Asian plant genus Phellodendron is known to contain several very important compounds that have biological action. The main purpose of this study was to determine whether seeds of Phellodendron amurense var. wilsonii can be stored and to characterize their dormancy. Seeds of this taxon stored at -20 and -80 degrees C and in liquid nitrogen retained their high germinability, indicating that they have orthodox storage behavior. Intact seeds from freshly collected fruits were dormant and required 12 weeks of cold stratification at 4 degrees C for complete germination. Scarifying the seed coat was partially effective in breaking seed dormancy. Exogenous gibberellins (GA(3), GA(4) and GA(4+7)) promoted germination of scarified seeds, GA(4) and GA(4+7) being more effective than GA(3). Fluridone, an abscisic acid (ABA) biosynthesis inhibitor, was efficient in breaking dormancy, but it was less effective than GA(4) or GA(4+7) alone. Paclobutrazol, a GA biosynthesis inhibitor, inhibited seed germination, and the inhibitory effect was reversed completely by GA(4) and by GA(4+7). ABA content of seeds subjected to cold stratification or to incubation at 35/10 degrees C, which enhanced seed germination, was reduced about four- to sixfold compared to that of fresh seeds. Higher concentrations of GA(3), GA(4) and GA(7) were detected in nondormant seeds and in seeds with an emerged radicle than in fresh seeds. Present results seem to indicate that dormancy in P. amurense var. wilsonii seeds is imposed partially by the seed coat and partially by high ABA content. ABA content decreased and GA(3), GA(4) and GA(7) content increased during germination.

  19. Effects of abscisic acid, ethylene and sugars on the mobilization of storage proteins and carbohydrates in seeds of the tropical tree Sesbania virgata (Leguminosae).

    Science.gov (United States)

    Tonini, Patricia Pinho; Purgatto, Eduardo; Buckeridge, Marcos Silveira

    2010-10-01

    Endospermic legumes are abundant in tropical forests and their establishment is closely related to the mobilization of cell-wall storage polysaccharides. Endosperm cells also store large numbers of protein bodies that play an important role as a nitrogen reserve in this seed. In this work, a systems approach was adopted to evaluate some of the changes in carbohydrates and hormones during the development of seedlings of the rain forest tree Sesbania virgata during the period of establishment. Seeds imbibed abscisic acid (ABA), glucose and sucrose in an atmosphere of ethylene, and the effects of these compounds on the protein contents, α-galactosidase activity and endogenous production of ABA and ethylene by the seeds were observed. The presence of exogenous ABA retarded the degradation of storage protein in the endosperm and decreased α-galactosidase activity in the same tissue during galactomannan degradation, suggesting that ABA represses enzyme action. On the other hand, exogenous ethylene increased α-galactosidase activity in both the endosperm and testa during galactomannan degradation, suggesting an inducing effect of this hormone on the hydrolytic enzymes. Furthermore, the detection of endogenous ABA and ethylene production during the period of storage mobilization and the changes observed in the production of these endogenous hormones in the presence of glucose and sucrose, suggested a correlation between the signalling pathway of these hormones and the sugars. These findings suggest that ABA, ethylene and sugars play a role in the control of the hydrolytic enzyme activities in seeds of S. virgata, controlling the process of storage degradation. This is thought to ensure a balanced flow of the carbon and nitrogen for seedling development.

  20. The core regulatory network of the abscisic acid pathway in banana: genome-wide identification and expression analyses during development, ripening, and abiotic stress.

    Science.gov (United States)

    Hu, Wei; Yan, Yan; Shi, Haitao; Liu, Juhua; Miao, Hongxia; Tie, Weiwei; Ding, Zehong; Ding, XuPo; Wu, Chunlai; Liu, Yang; Wang, Jiashui; Xu, Biyu; Jin, Zhiqiang

    2017-08-29

    Abscisic acid (ABA) signaling plays a crucial role in developmental and environmental adaptation processes of plants. However, the PYL-PP2C-SnRK2 families that function as the core components of ABA signaling are not well understood in banana. In the present study, 24 PYL, 87 PP2C, and 11 SnRK2 genes were identified from banana, which was further supported by evolutionary relationships, conserved motif and gene structure analyses. The comprehensive transcriptomic analyses showed that banana PYL-PP2C-SnRK2 genes are involved in tissue development, fruit development and ripening, and response to abiotic stress in two cultivated varieties. Moreover, comparative expression analyses of PYL-PP2C-SnRK2 genes between BaXi Jiao (BX) and Fen Jiao (FJ) revealed that PYL-PP2C-SnRK2-mediated ABA signaling might positively regulate banana fruit ripening and tolerance to cold, salt, and osmotic stresses. Finally, interaction networks and co-expression assays demonstrated that the core components of ABA signaling were more active in FJ than in BX in response to abiotic stress, further supporting the crucial role of the genes in tolerance to abiotic stress in banana. This study provides new insights into the complicated transcriptional control of PYL-PP2C-SnRK2 genes, improves the understanding of PYL-PP2C-SnRK2-mediated ABA signaling in the regulation of fruit development, ripening, and response to abiotic stress, and identifies some candidate genes for genetic improvement of banana.

  1. Abscisic Acid Induced Changes in Production of Primary and Secondary Metabolites, Photosynthetic Capacity, Antioxidant Capability, Antioxidant Enzymes and Lipoxygenase Inhibitory Activity of Orthosiphon stamineus Benth.

    Directory of Open Access Journals (Sweden)

    Mohd Hafiz Ibrahim

    2013-07-01

    Full Text Available An experiment was conducted to investigate and distinguish the relationships in the production of total phenolics, total flavonoids, soluble sugars, H2O2, O2−, phenylalanine ammonia lyase (PAL activity, leaf gas exchange, antioxidant activity, antioxidant enzyme activity [ascorbate peroxidase (APX, catalase (CAT, superoxide dismutase (SOD and Lipoxygenase inhibitory activity (LOX] under four levels of foliar abscisic acid (ABA application (0, 2, 4, 6 µM for 15 weeks in Orthosiphon stamineus Benth. It was found that the production of plant secondary metabolites, soluble sugars, antioxidant activity, PAL activity and LOX inhibitory activity was influenced by foliar application of ABA. As the concentration of ABA was increased from 0 to 6 µM the production of total phenolics, flavonoids, sucrose, H2O2, O2−, PAL activity and LOX inhibitory activity was enhanced. It was also observed that the antioxidant capabilities (DPPH and ORAC were increased. This was followed by increases in production of antioxidant enzymes APX, CAT and SOD. Under high application rates of ABA the net photosynthesis and stomatal conductance was found to be reduced. The production of primary and secondary metabolites displayed a significant positive relationship with H2O2 (total phenolics, r2 = 0.877; total flavonoids, r2 = 0.812; p ≤ 0.05 and O2− (total phenolics, r2 = 0.778; total flavonoids, r2 = 0.912; p ≤ 0.05. This indicated that increased oxidative stress at high application rates of ABA, improved the production of phytochemicals.

  2. Local root abscisic acid (ABA) accumulation depends on the spatial distribution of soil moisture in potato: implications for ABA signalling under heterogeneous soil drying.

    Science.gov (United States)

    Puértolas, Jaime; Conesa, María R; Ballester, Carlos; Dodd, Ian C

    2015-04-01

    Patterns of root abscisic acid (ABA) accumulation ([ABA]root), root water potential (Ψroot), and root water uptake (RWU), and their impact on xylem sap ABA concentration ([X-ABA]) were measured under vertical partial root-zone drying (VPRD, upper compartment dry, lower compartment wet) and horizontal partial root-zone drying (HPRD, two lateral compartments: one dry, the other wet) of potato (Solanum tuberosum L.). When water was withheld from the dry compartment for 0-10 d, RWU and Ψroot were similarly lower in the dry compartment when soil volumetric water content dropped below 0.22cm(3) cm(-3) for both spatial distributions of soil moisture. However, [ABA]root increased in response to decreasing Ψroot in the dry compartment only for HPRD, resulting in much higher ABA accumulation than in VPRD. The position of the sampled roots (~4cm closer to the surface in the dry compartment of VPRD than in HPRD) might account for this difference, since older (upper) roots may accumulate less ABA in response to decreased Ψroot than younger (deeper) roots. This would explain differences in root ABA accumulation patterns under vertical and horizontal soil moisture gradients reported in the literature. In our experiment, these differences in root ABA accumulation did not influence [X-ABA], since the RWU fraction (and thus ABA export to shoots) from the dry compartment dramatically decreased simultaneously with any increase in [ABA]root. Thus, HPRD might better trigger a long-distance ABA signal than VPRD under conditions allowing simultaneous high [ABA]root and relatively high RWU fraction. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  3. Suppression Subtractive Hybridization Analysis of Genes Regulated by Application of Exogenous Abscisic Acid in Pepper Plant (Capsicum annuum L. Leaves under Chilling Stress.

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    Wei-Li Guo

    Full Text Available Low temperature is one of the major factors limiting pepper (Capsicum annuum L. production during winter and early spring in non-tropical regions. Application of exogenous abscisic acid (ABA effectively alleviates the symptoms of chilling injury, such as wilting and formation of necrotic lesions on pepper leaves; however, the underlying molecular mechanism is not understood. The aim of this study was to identify genes that are differentially up- or downregulated in ABA-pretreated hot pepper seedlings incubated at 6°C for 48 h, using a suppression subtractive hybridization (SSH method. A total of 235 high-quality ESTs were isolated, clustered and assembled into a collection of 73 unigenes including 18 contigs and 55 singletons. A total of 37 unigenes (50.68% showed similarities to genes with known functions in the non-redundant database; the other 36 unigenes (49.32% showed low similarities or unknown functions. Gene ontology analysis revealed that the 37 unigenes could be classified into nine functional categories. The expression profiles of 18 selected genes were analyzed using quantitative RT-PCR; the expression levels of 10 of these genes were at least two-fold higher in the ABA-pretreated seedlings under chilling stress than water-pretreated (control plants under chilling stress. In contrast, the other eight genes were downregulated in ABA-pretreated seedlings under chilling stress, with expression levels that were one-third or less of the levels observed in control seedlings under chilling stress. These results suggest that ABA can positively and negatively regulate genes in pepper plants under chilling stress.

  4. Dormancy termination of western white pine (Pinus monticola Dougl. Ex D. Don) seeds is associated with changes in abscisic acid metabolism.

    Science.gov (United States)

    Feurtado, J Allan; Ambrose, Stephen J; Cutler, Adrian J; Ross, Andrew R S; Abrams, Suzanne R; Kermode, Allison R

    2004-02-01

    Western white pine (Pinus monticola) seeds exhibit deep dormancy at maturity and seed populations require several months of moist chilling to reach their uppermost germination capacities. Abscisic acid (ABA) and its metabolites, phaseic acid (PA), dihydrophaseic acid (DPA), 7'-hydroxy ABA (7'OH ABA) and ABA-glucose ester (ABA-GE), were quantified in western white pine seeds during dormancy breakage (moist chilling) and germination using an HPLC-tandem mass spectrometry method with multiple reaction monitoring and internal standards incorporating deuterium-labeled analogs. In the seed coat, ABA and metabolite levels were high in dry seeds, but declined precipitously during the pre-moist-chilling water soak to relatively low levels thereafter. In the embryo and megagametophyte, ABA levels decreased significantly during moist chilling, coincident with an increase in the germination capacity of seeds. ABA catabolism occurred via several routes, depending on the stage and the seed tissue. Moist chilling of seeds led to increases in PA and DPA levels in both the embryo and megagametophyte. Within the embryo, 7'OH ABA and ABA-GE also accumulated during moist chilling; however, 7'OH ABA peaked early in germination. Changes in ABA flux, i.e. shifts in the ratio between biosynthesis and catabolism, occurred at three distinct stages during the transition from dormant seed to seedling. During moist chilling, the relative rate of ABA catabolism exceeded ABA biosynthesis. This trend became even more pronounced during germination, and germination was also accompanied by a decrease in the ABA catabolites DPA and PA, presumably as a result of their further metabolism and/or leaching/transport. The transition from germination to post-germinative growth was accompanied by a shift toward ABA biosynthesis. Dormant imbibed seeds, kept in warm moist conditions for 30 days (after an initial 13 days of soaking), maintained high ABA levels, while the amounts of PA, 7'OH ABA, and DPA

  5. Expression analysis of β-glucosidase genes that regulate abscisic acid homeostasis during watermelon (Citrullus lanatus) development and under stress conditions.

    Science.gov (United States)

    Li, Qian; Li, Ping; Sun, Liang; Wang, Yanping; Ji, Kai; Sun, Yufei; Dai, Shengjie; Chen, Pei; Duan, Chaorui; Leng, Ping

    2012-01-01

    The aim of this study was to obtain new insights into the mechanisms that regulate endogenous abscisic acid (ABA) levels by β-glucosidase genes during the development of watermelons (Citrullus lanatus) and under drought stress conditions. In total, five cDNAs from watermelons were cloned by using reverse transcription-PCR (RT-PCR). They included three cDNAs (ClBG1, ClBG2 and ClBG3) homologous to those that encode β-glucosidase l that hydrolyzes the ABA glucose ester (ABA-GE) to release active ABA, ClNCED4, which encodes 9-cis-epoxycarotenoid dioxygenase (NCED), a key enzyme in ABA biosynthesis, and ClCYP707A1, encoding ABA 8'-hydroxylase. A BLAST homology search revealed that the sequences of cDNAs and the deduced amino acids of these genes showed a high degree of homology to comparable molecules of other plant species. During fruit development and ripening, the expressions of ClBG1, ClNCED4 and ClCYP707A1 were relatively low at an early stage, increased rapidly along with fruit ripening, and reached the highest levels at 27 days after full bloom (DAFB) at the harvest stage. This trend was consistent with the accumulation of ABA. The ClBG2 gene on the other hand was highly expressed at 5 DAFB, and then decreased gradually with fruit development. Unlike ClBG1 and ClBG2, the expression of ClBG3 was low at an early stage; its expression peak occurred at 15 DAFB and then declined to the lowest point. When watermelon seedlings were subjected to drought stress, expressions of ClBG1 and ClCYP707A1 were significantly down-regulated, while expressions of ClBG2 and ClNCED4 were up-regulated in the roots, stems and leaves. The expression of ClBG3 was down-regulated in root tissue, but was up-regulated in stems and leaves. In conclusion, endogenous ABA content was modulated by a dynamic balance between biosynthesis and catabolism regulated by ClNCED4, ClCYP707A1 and ClBGs during development and under drought stress condition. It seems likely that β-glucosidase genes are

  6. Age and sex-related changes in cytokinins, auxins and abscisic acid in a centenarian relict herbaceous perennial.

    Science.gov (United States)

    Oñate, Marta; García, Maria B; Munné-Bosch, Sergi

    2012-02-01

    It is still an unsolved question of fundamental biology if, and how, perennial plants senesce. Here, age- and sex-related changes in phytohormones were tested in Borderea pyrenaica, a small dioecious geophyte relict of the Tertiary with one of the longest lifespan ever recorded for any non-clonal herb (more than 300 years). Biomass allocation, together with levels of cytokinins, auxins and absicisic acid, and other indicators of leaf physiology (chlorophylls, lipid peroxidation and F (v)/F (m) ratio) were measured in juvenile and mature plants, including both males and females of three age classes (up to 50 years, 50-100 years, and over 100 years). Plants maintained intact capacity of their vegetative growth and reproductive potential. Cytokinin levels decreased with age, but only in females. Such sex-related differences, however, were not associated with symptoms of physiological deterioration in leaves, but with an increased reproductive effort in females. It is concluded that B. pyrenaica does not show clear signs of senescence at the organism level. Altered cytokinin levels in females were associated with their reproductive effort, rather than to a degenerative process. The alternate use of five meristematic points in the tuber could explain the extraordinary longevity of this species.

  7. Negative Regulation of Abscisic Acid Signaling by the Fagus sylvatica FsPP2C1 Plays A Role in Seed Dormancy Regulation and Promotion of Seed Germination1

    Science.gov (United States)

    González-García, Mary Paz; Rodríguez, Dolores; Nicolás, Carlos; Rodríguez, Pedro Luis; Nicolás, Gregorio; Lorenzo, Oscar

    2003-01-01

    FsPP2C1 was previously isolated from beech (Fagus sylvatica) seeds as a functional protein phosphatase type-2C (PP2C) with all the conserved features of these enzymes and high homology to ABI1, ABI2, and PP2CA, PP2Cs identified as negative regulators of ABA signaling. The expression of FsPP2C1 was induced upon abscisic acid (ABA) treatment and was also up-regulated during early weeks of stratification. Furthermore, this gene was specifically expressed in ABA-treated seeds and was hardly detectable in vegetative tissues. In this report, to provide genetic evidence on FsPP2C1 function in seed dormancy and germination, we used an overexpression approach in Arabidopsis because transgenic work is not feasible in beech. Constitutive expression of FsPP2C1 under the cauliflower mosaic virus 35S promoter confers ABA insensitivity in Arabidopsis seeds and, consequently, a reduced degree of seed dormancy. Additionally, transgenic 35S:FsPP2C1 plants are able to germinate under unfavorable conditions, as inhibitory concentrations of mannitol, NaCl, or paclobutrazol. In vegetative tissues, Arabidopsis FsPP2C1 transgenic plants show ABA-resistant early root growth and diminished induction of the ABA-response genes RAB18 and KIN2, but no effect on stomatal closure regulation. Seed and vegetative phenotypes of Arabidopsis 35S:FsPP2C1 plants suggest that FsPP2C1 negatively regulates ABA signaling. The ABA inducibility of FsPP2C1 expression, together with the transcript accumulation mainly in seeds, suggest that it could play an important role modulating ABA signaling in beechnuts through a negative feedback loop. Finally, we suggest that negative regulation of ABA signaling by FsPP2C1 is a factor contributing to promote the transition from seed dormancy to germination during early weeks of stratification. PMID:12970481

  8. Importance of Abscisic Acid (ABA in the In Vitro Conservation of Cassava (Manihot esculenta Crantz Importancia del Ácido Abscísico (ABA en la Conservación In Vitro de la Yuca (Manihot esculenta Crantz

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    L. Pedro Barrueto Cid

    2008-09-01

    Full Text Available The conventional technology for in vitro plant conservation for cassava (Manihot esculenta Crantz germplasm collections is laborious due to the need for several sub-culturing procedures per year. This practice implies high costs for medium preparation, tissue culture tubes, time-consuming labor, risks of contamination, mislabeling of accession, and the need for large growth chambers. We have developed a new procedure using in vitro cultivated nodal axillary buds treated with different abscisic acid (ABA concentrations to reduce the time for recycling transplants cultivated in a SP basic nutritive medium. Nodal explants were stored for three months with ABA. Plants were obtained after nodal axillary buds were placed in SP medium without ABA. Results indicated that 20 and 30 mM ABA induced bud dormancy and delayed sprouting without affecting subsequent growth of plants after treatment.La tecnología usual para conservación in vitro de colecciones de germoplasma de yuca (Manihotesculenta Crantz es corrientemente laboriosa y emplea varias transferencias por año. Este procedimiento envuelve altos costos en preparación de medios, consumo de tiempo, riesgos de manipulación y necesidad de mucho espacio para la mantención de colecciones en cámaras de cultivos. Se desarrolló un nuevo procedimiento usando yemas axilares nodales cultivadas in vitro con diferentes concentraciones de ácido abscísico (ABA, con el objetivo de reducir los ciclos de transferencia de los cultivos mantenidos en un medio nutritivo básico tal como el SP. Los segmentos nodales fueron almacenados por tres meses en presencia de ABA. Las plantas fueron obtenidas después que los segmentos nodales fueron transferidos al medio SP sin ABA. Los resultados indican que 20 y 30 mM de ABA indujeron una completa dormancia de yemas, sin afectar el desarrollo posterior de las yemas nodales y su consecuente conversión en planta.

  9. Gene expression analyses in tomato near isogenic lines provide evidence for ethylene and abscisic acid biosynthesis fine-tuning during arbuscular mycorrhiza development.

    Science.gov (United States)

    Fracetto, Giselle Gomes Monteiro; Peres, Lázaro Eustáquio Pereira; Lambais, Marcio Rodrigues

    2017-07-01

    Plant responses to the environment and microorganisms, including arbuscular mycorrhizal fungi, involve complex hormonal interactions. It is known that abscisic acid (ABA) and ethylene may be involved in the regulation of arbuscular mycorrhiza (AM) and that part of the detrimental effects of ABA deficiency in plants is due to ethylene overproduction. In this study, we aimed to determine whether the low susceptibility to mycorrhizal colonization in ABA-deficient mutants is due to high levels of ethylene and whether AM development is associated with changes in the steady-state levels of transcripts of genes involved in the biosynthesis of ethylene and ABA. For that, tomato (Solanum lycopersicum) ethylene overproducer epinastic (epi) mutant and the ABA-deficient notabilis (not) and sitiens (sit) mutants, in the same Micro-Tom (MT) genetic background, were inoculated with Rhizophagus clarus, and treated with the ethylene biosynthesis inhibitor aminoethoxyvinylglycine (AVG). The development of AM, as well as the steady-state levels of transcripts involved in ethylene (LeACS2, LeACO1 and LeACO4) and ABA (LeNCED) biosynthesis, was determined. The intraradical colonization in epi, not and sit mutants was significantly reduced compared to MT. The epi mutant completely restored the mycorrhizal colonization to the levels of MT with the application of 10 µM of AVG, probably due to the inhibition of the ACC synthase gene expression. The steady-state levels of LeACS2 and LeACO4 transcripts were induced in mycorrhizal roots of MT, whereas the steady-state levels of LeACO1 and LeACO4 transcripts were significantly induced in sit, and the steady-state levels of LeNCED transcripts were significantly induced in all genotypes and in mycorrhizal roots of epi mutants treated with AVG. The reduced mycorrhizal colonization in sit mutants seems not to be limited by ethylene production via ACC oxidase regulation. Both ethylene overproduction and ABA deficiency impaired AM fungal

  10. Treatment of acid mine wastewaters

    International Nuclear Information System (INIS)

    Hayward, D.; Barnard, R.

    1993-01-01

    Acid mine drainage often results from the oxidation sulfide minerals to form sulfuric acid. As a consequence, high concentrations of metals in the both the suspended and dissolved state result from the low pH water. This paper discusses several of the more common treatment methods for acid mine drainage including the use of chemical precipitation agents, pH correction agents, filtration methods, and biodegradation methods. Advanced treatment technologies are also briefly described and include microfiltration, reverse osmosis, ion exchange, and electrodialysis

  11. EL ÁCIDO ABSCÍSICO ACELERA EL DESARROLLO FLORAL DE SOLIDAGO EN DÍAS CORTOS ABSCISIC ACID SPEED UP FLORAL DEVELOPMENT OF SOLIDAGO UNDER SHORT DAYS

    Directory of Open Access Journals (Sweden)

    Víctor Julio Flórez Roncancio

    2009-06-01

    Full Text Available Solidago x luteus (M. L. Greene Broulliet y Semple (= x Solidaster hybridus, x S. luteus es una planta que responde a días cortos (DC para el desarrollo floral. En este proceso se ha establecido la participación de varias fitohormonas, entre éstas, la presencia del ácido abscísico (ABA en zonas y periodos específicos durante el desarrollo de la flor lo cual sugiere su acción promotora en la velocidad de antesis floral de esta especie en DC. En este trabajo se buscaron nuevos indicios de la participación de fitohormonas presentes en la fracción ácida con el proceso de floración. En una primera etapa, extractos foliares provenientes de hojas de plantas en días largos (caracterizadas por menor velocidad de antesis floral se aplicaron en botones florales de plantas en días cortos (caracterizadas por una mayor velocidad de antesis floral. Se realizaron ocho aplicaciones con diferentes frecuencias totalizando un periodo de tratamiento de 25 días. Los resultados mostraron que las sustancias presentes en los extractos de la fracción ácida, no alteran la velocidad promedio de antesis floral en los botones florales de plantas en DC. En la segunda etapa del experimento, la cuantificación de los extractos por ELISA, permitió establecer una mayor concentración de ABA en los extractos de hojas y de botones florales de plantas en DC y de botones florales en el inicio del tratamiento. Estos resultados confirman la relación del ABA con la mayor velocidad de antesis floral en plantas de Solidago x luteus en condiciones de DC.Solidago x luteus (M.L. Greene Broulliet & Semple (= x Solidaster hybridus, x S. luteus is a plant that respond to short days (SD for flower development. In this process, there has been established the involvement of many phytohormones, between these, the presence of the abscisic acid (ABA in zones and specific periods during flower development, suggests its promoter roll on the floral anthesis period of this species under

  12. HAB1–SWI3B Interaction Reveals a Link between Abscisic Acid Signaling and Putative SWI/SNF Chromatin-Remodeling Complexes in Arabidopsis[C][W

    Science.gov (United States)

    Saez, Angela; Rodrigues, Americo; Santiago, Julia; Rubio, Silvia; Rodriguez, Pedro L.

    2008-01-01

    Abscisic acid (ABA) has an important role for plant growth, development, and stress adaptation. HYPERSENSITIVE TO ABA1 (HAB1) is a protein phosphatase type 2C that plays a key role as a negative regulator of ABA signaling; however, the molecular details of HAB1 action in this process are not known. A two-hybrid screen revealed that SWI3B, an Arabidopsis thaliana homolog of the yeast SWI3 subunit of SWI/SNF chromatin-remodeling complexes, is a prevalent interacting partner of HAB1. The interaction mapped to the N-terminal half of SWI3B and required an intact protein phosphatase catalytic domain. Bimolecular fluorescence complementation and coimmunoprecipitation assays confirmed the interaction of HAB1 and SWI3B in the nucleus of plant cells. swi3b mutants showed a reduced sensitivity to ABA-mediated inhibition of seed germination and growth and reduced expression of the ABA-responsive genes RAB18 and RD29B. Chromatin immunoprecipitation experiments showed that the presence of HAB1 in the vicinity of RD29B and RAB18 promoters was abolished by ABA, which suggests a direct involvement of HAB1 in the regulation of ABA-induced transcription. Additionally, our results uncover SWI3B as a novel positive regulator of ABA signaling and suggest that HAB1 modulates ABA response through the regulation of a putative SWI/SNF chromatin-remodeling complex. PMID:19033529

  13. Damage to the plasmalemma, chloroplasts and photosystem II after water shortage and high-temperature stress in two lines of maize which differ in endogenous levels of abscisic acid and drought resistance

    Energy Technology Data Exchange (ETDEWEB)

    Ristic, Z.; Cass, D.D. (Univ. of Alberta, Edmonton (Canada))

    1991-05-01

    This study examines damage to the plasmalemma, chloroplasts and photosystem II (PS II), and the rate of CO{sub 2} fixation after exposure to 7-d water shortage followed by 6-h (WTS-6) or 24-h (WTS-24) high temperature (45C) stress in the high-level. Abscisic acid (ABA) drought-resistant (DR) line of maize ZPBL 1304 and the low-level ABA drought-sensitive line ZPL 389. Seven-day water shortage followed by 6-h high-temperature stress slightly damaged PS II in the DR line ZPBL 1304. The DS line ZPL 389 was affected by WTS-6 to a great extent; however, the stress-caused damage to this line was reversible. Exposure to WTS-24 caused reversible damage to the plasmalemma, chloroplasts and PS II in DR line. The DS line was not capable of withstanding severe stress conditions; WTS-24 killed almost all the plants. The results on the rate of CO{sub 2} fixation were in agreement with those on the damage to the plasmalemma, chloroplasts and PS II. Considerable drought and heat resistance was apparent in the line (ZPBL 1304) which synthesizes a unique band of heat-shock protein(s) of 45 KDa. In conclusion, the high-level ABA DR line ZPBL 1304 showed much greater capability of withstanding WTS than the low-level ABA DS line ZPL 389.

  14. Resistance to Botrytis cinerea in sitiens, an Abscisic Acid-Deficient Tomato Mutant, Involves Timely Production of Hydrogen Peroxide and Cell Wall Modifications in the Epidermis1[C][W][OA

    Science.gov (United States)

    Asselbergh, Bob; Curvers, Katrien; França, Soraya C.; Audenaert, Kris; Vuylsteke, Marnik; Van Breusegem, Frank; Höfte, Monica

    2007-01-01

    Plant defense mechanisms against necrotrophic pathogens, such as Botrytis cinerea, are considered to be complex and to differ from those that are effective against biotrophs. In the abscisic acid-deficient sitiens tomato (Solanum lycopersicum) mutant, which is highly resistant to B. cinerea, accumulation of hydrogen peroxide (H2O2) was earlier and stronger than in the susceptible wild type at the site of infection. In sitiens, H2O2 accumulation was observed from 4 h postinoculation (hpi), specifically in the leaf epidermal cell walls, where it caused modification by protein cross-linking and incorporation of phenolic compounds. In wild-type tomato plants, H2O2 started to accumulate 24 hpi in the mesophyll layer and was associated with spreading cell death. Transcript-profiling analysis using TOM1 microarrays revealed that defense-related transcript accumulation prior to infection was higher in sitiens than in wild type. Moreover, further elevation of sitiens defense gene expression was stronger than in wild type 8 hpi both in number of genes and in their expression levels and confirmed a role for cell wall modification in the resistant reaction. Although, in general, plant defense-related reactive oxygen species formation facilitates necrotrophic colonization, these data indicate that timely hyperinduction of H2O2-dependent defenses in the epidermal cell wall can effectively block early development of B. cinerea. PMID:17573540

  15. Over-expression of LeNCED1 in tomato (Solanum lycopersicum L.) with the rbcS3C promoter allows recovery of lines that accumulate very high levels of abscisic acid and exhibit severe phenotypes.

    Science.gov (United States)

    Tung, Swee Ang; Smeeton, Rachel; White, Charlotte A; Black, Colin R; Taylor, Ian B; Hilton, Howard W; Thompson, Andrew J

    2008-07-01

    Previous work where 9-cis-epoxycarotenoid dioxygenase (NCED) was over-expressed using the constitutive Gelvin Superpromoter resulted in mild increases in abscisic acid (ABA) accumulation, accompanied by stomatal closure and increased water-use efficiency (WUE), but with apparently little impact on long-term biomass production. However, one of the negative effects of the over-expression of NCED using constitutive promoters in tomato was increased seed dormancy. Here we report the use of the rbcS3C promoter, from a gene encoding the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), to drive LeNCED1 transgene expression in tomato in a light-responsive and circadian manner. In comparison to the constitutive promoter, the rbcS3C promoter allowed the generation of transgenic plants with much higher levels of ABA accumulation in leaves and sap, but the effect on seed dormancy was diminished. These plants displayed the expected reductions in stomatal conductance and CO(2) assimilation, but they also exhibited a severe set of symptoms that included perturbed cotyledon release from the testa, increased photobleaching in young seedlings, substantially reduced chlorophyll and carotenoid content, interveinal leaf flooding, and greatly reduced growth. These symptoms illustrate adverse consequences of long-term, very high ABA accumulation. Only more moderate increases in ABA biosynthesis are likely to be useful in the context of agriculture. Implications are discussed for the design of transgenic 'high ABA' plants that exhibit increased WUE but have minimal negative phenotypic effects.

  16. Genetic Analysis of Physcomitrella patens Identifies ABSCISIC ACID NON-RESPONSIVE, a Regulator of ABA Responses Unique to Basal Land Plants and Required for Desiccation Tolerance[CC-BY

    Science.gov (United States)

    Kamisugi, Yasuko; Trinh, Chi H.; Schmutz, Jeremy; Muchero, Wellington; Melkonian, Michael; Rothfels, Carl J.; Li, Fay-Wei; Larsson, Anders; Edwards, Thomas A.

    2016-01-01

    The anatomically simple plants that first colonized land must have acquired molecular and biochemical adaptations to drought stress. Abscisic acid (ABA) coordinates responses leading to desiccation tolerance in all land plants. We identified ABA nonresponsive mutants in the model bryophyte Physcomitrella patens and genotyped a segregating population to map and identify the ABA NON-RESPONSIVE (ANR) gene encoding a modular protein kinase comprising an N-terminal PAS domain, a central EDR domain, and a C-terminal MAPKKK-like domain. anr mutants fail to accumulate dehydration tolerance-associated gene products in response to drought, ABA, or osmotic stress and do not acquire ABA-dependent desiccation tolerance. The crystal structure of the PAS domain, determined to 1.7-Å resolution, shows a conserved PAS-fold that dimerizes through a weak dimerization interface. Targeted mutagenesis of a conserved tryptophan residue within the PAS domain generates plants with ABA nonresponsive growth and strongly attenuated ABA-responsive gene expression, whereas deleting this domain retains a fully ABA-responsive phenotype. ANR orthologs are found in early-diverging land plant lineages and aquatic algae but are absent from more recently diverged vascular plants. We propose that ANR genes represent an ancestral adaptation that enabled drought stress survival of the first terrestrial colonizers but were lost during land plant evolution. PMID:27194706

  17. The Arabidopsis adaptor protein AP-3µ interacts with the G-protein β subunit AGB1 and is involved in abscisic acid regulation of germination and post-germination development

    Science.gov (United States)

    Tsugama, Daisuke; Takano, Tetsuo

    2013-01-01

    Heterotrimeric G-proteins (G-proteins) have been implicated in ubiquitous signalling mechanisms in eukaryotes. In plants, G-proteins modulate hormonal and stress responses and regulate diverse developmental processes. However, the molecular mechanisms of their functions are largely unknown. A yeast two-hybrid screen was performed to identify interacting partners of the Arabidopsis G-protein β subunit AGB1. One of the identified AGB1-interacting proteins is the Arabidopsis adaptor protein AP-3µ. The interaction between AGB1 and AP-3µ was confirmed by an in vitro pull-down assay and bimolecular fluorescence complementation assay. Two ap-3µ T-DNA insertional mutants were found to be hyposensitive to abscisic acid (ABA) during germination and post-germination growth, whereas agb1 mutants were hypersensitive to ABA. During seed germination, agb1/ap-3µ double mutants were more sensitive to ABA than the wild type but less sensitive than agb1 mutants. However, in post-germination growth, the double mutants were as sensitive to ABA as agb1 mutants. These data suggest that AP-3µ positively regulates the ABA responses independently of AGB1 in seed germination, while AP-3µ does require AGB1 to regulate ABA responses during post-germination growth. PMID:24098050

  18. Natural modifiers of seed longevity in the Arabidopsis mutants abscisic acid insensitive3-5 (abi3-5) and leafy cotyledon1-3 (lec1-3).

    Science.gov (United States)

    Sugliani, Matteo; Rajjou, Loïc; Clerkx, Emile J M; Koornneef, Maarten; Soppe, Wim J J

    2009-12-01

    *Seed longevity is an important trait in many crops and is essential for the success of most land plant species. Current knowledge of its molecular regulation is limited. The Arabidopsis mutants abscisic acid insensitive3-5 (abi3-5) and leafy cotyledon1-3 (lec1-3) have impaired seed maturation and quickly lose seed viability. abi3-5 and lec1-3 were used as sensitized genetic backgrounds for the study of seed longevity. *We exploited the natural variation of Arabidopsis to create introgression lines from the Seis am Schlern and Shahdara accessions in, respectively, the abi3-5 and lec1-3 backgrounds. These lines carry natural modifiers of the abi3 and lec1 phenotypes. Longevity tests and a proteomic analysis were conducted to describe the seed physiology of each line. *The modifier lines showed improved seed longevity. The Shahdara modifiers can partially re-establish the seed developmental programs controlled by LEC1 and restore the accumulation of seed storage proteins that are reduced in abi3-5 and lec1-3. *The isolation and characterization of natural modifiers of the seed maturation mutants abi3-5 and lec1-3, and the analysis of their seed proteomes, advance our current understanding of seed longevity.

  19. Virus-induced down-regulation of GmERA1A and GmERA1B genes enhances the stomatal response to abscisic acid and drought resistance in soybean.

    Directory of Open Access Journals (Sweden)

    Takuya Ogata

    Full Text Available Drought is a major threat to global soybean production. The limited transformation potential and polyploid nature of soybean have hindered functional analysis of soybean genes. Previous research has implicated farnesylation in the plant's response to abscisic acid (ABA and drought tolerance. We therefore used virus-induced gene silencing (VIGS to evaluate farnesyltransferase genes, GmERA1A and GmERA1B (Glycine max Enhanced Response to ABA1-A and -B, as potential targets for increasing drought resistance in soybean. Apple latent spherical virus (ALSV-mediated GmERA1-down-regulated soybean leaves displayed an enhanced stomatal response to ABA and reduced water loss and wilting under dehydration conditions, suggesting that GmERA1A and GmERA1B negatively regulate ABA signaling in soybean guard cells. The findings provide evidence that the ALSV-VIGS system, which bypasses the need to generate transgenic plants, is a useful tool for analyzing gene function using only a single down-regulated leaf. Thus, the ALSV-VIGS system could constitute part of a next-generation molecular breeding pipeline to accelerate drought resistance breeding in soybean.

  20. Enhanced Abscisic Acid-Mediated Responses in nia1nia2noa1-2 Triple Mutant Impaired in NIA/NR- and AtNOA1-Dependent Nitric Oxide Biosynthesis in Arabidopsis1[W

    Science.gov (United States)

    Lozano-Juste, Jorge; León, José

    2010-01-01

    Nitric oxide (NO) regulates a wide range of plant processes from development to environmental adaptation. Despite its reported regulatory functions, it remains unclear how NO is synthesized in plants. We have generated a triple nia1nia2noa1-2 mutant that is impaired in nitrate reductase (NIA/NR)- and Nitric Oxide-Associated1 (AtNOA1)-mediated NO biosynthetic pathways. NO content in roots of nia1nia2 and noa1-2 plants was lower than in wild-type plants and below the detection limit in nia1nia2noa1-2 plants. NIA/NR- and AtNOA1-mediated biosynthesis of NO were thus active and responsible for most of the NO production in Arabidopsis (Arabidopsis thaliana). The nia1nia2noa1-2 plants displayed reduced size, fertility, and seed germination potential but increased dormancy and resistance to water deficit. The increasing deficiency in NO of nia1nia2, noa1-2, and nia1nia2noa1-2 plants correlated with increased seed dormancy, hypersensitivity to abscisic acid (ABA) in seed germination and establishment, as well as dehydration resistance. In nia1nia2noa1-2 plants, enhanced drought tolerance was due to a very efficient stomata closure and inhibition of opening by ABA, thus uncoupling NO from ABA-triggered responses in NO-deficient guard cells. The NO-deficient mutants in NIA/NR- and AtNOA1-mediated pathways in combination with the triple mutant will be useful tools to functionally characterize the role of NO and the contribution of both biosynthetic pathways in regulating plant development and defense. PMID:20007448

  1. Treatment of acid mining waters

    Energy Technology Data Exchange (ETDEWEB)

    S. Santos; R. Machado; M. Joana Neiva Correia; Jorge R. Carvalho [Instituto Superior Tecnico, Lisbon (Portugal)

    2004-02-01

    The objective of this work was to study the possibility of achieving a selective removal of iron from acid mine waters (AMW) by precipitation/biosorption producing an easily filterable pulp and a solution containing valuable metals such as copper, zinc etc. This treatment is an alternative to the traditional neutralization with Ca(OH){sub 2}, that produces a precipitate of ferric hydroxide (Fe(OH){sub 3}) and gypsum (CaSO{sub 4}), which is extremely difficult to filter and is contaminated with heavy metals. The composition of the investigated solution was established in order to simulate a typical composition of AMW. To prevent the co-precipitation of the heavy metals in significant amounts, iron precipitation has to be carried out at low pH. The effect of the addition of a biomass (grape-stalks or cork powder) on the selective removal of iron and on the sedimentation and filtration operations was determined. The results showed that at pH 3 and for a solid-liquid ratio of 4 g/l it is possible to eliminate 65% of iron and only 5% of copper. Using 8 g/l of biomass the iron removal increased up to 85% of iron and 74% of copper, 90% of zinc and 99% of nickel remained in solution. The addition of the biomass to the pulp also improved the sedimentation and filtration operations.

  2. Abscisic Acid-Induced H2O2 Accumulation Enhances Antioxidant Capacity in Pumpkin-Grafted Cucumber Leaves under Ca(NO3)2 Stress

    Science.gov (United States)

    Shu, Sheng; Gao, Pan; Li, Lin; Yuan, Yinghui; Sun, Jin; Guo, Shirong

    2016-01-01

    With the aim to clarifying the role of the ABA/H2O2 signaling cascade in the regulating the antioxidant capacity of grafted cucumber plants in response to Ca(NO3)2 stress, we investigated the relationship between ABA-mediated H2O2 production and the activities of antioxidant enzymes in the leaves of pumpkin-grafted cucumber seedlings. The results showed that both ABA and H2O2 were detected in pumpkin-grafted cucumber seedlings in response to Ca(NO3)2 treatment within 0.5 h in the leaves and peaked at 3 and 6 h after Ca(NO3)2 treatment, respectively, compared to the levels under control conditions. The activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), and peroxidase (POD) in pumpkin-grafted cucumber leaves gradually increased over time and peaked at 12 h of Ca(NO3)2 stress. Furthermore, in the leaves of pumpkin-grafted cucumber seedlings, the H2O2 generation, the antioxidant enzyme activities and the expression of SOD, POD and cAPX were strongly blocked by an inhibitor of ABA under Ca(NO3)2 stress, but this effect was eliminated by the addition of exogenous ABA. Moreover, the activities and gene expressions of these antioxidant enzymes in pumpkin-grafted leaves were almost inhibited under Ca(NO3)2 stress by pretreatment with ROS scavengers. These results suggest that the pumpkin grafting-induced ABA accumulation mediated H2O2 generation, resulting in the induction of antioxidant defense systems in leaves exposed to Ca(NO3)2 stress in the ABA/H2O2 signaling pathway. PMID:27746808

  3. OsRACK1 Is Involved in Abscisic Acid- and H2O2-Mediated Signaling to Regulate Seed Germination in Rice (Oryza sativa, L.)

    Science.gov (United States)

    Zhang, Dongping; Chen, Li; Li, Dahong; Lv, Bing; Chen, Yun; Chen, Jingui; XuejiaoYan; Liang, Jiansheng

    2014-01-01

    The receptor for activated C kinase 1 (RACK1) is one member of the most important WD repeat–containing family of proteins found in all eukaryotes and is involved in multiple signaling pathways. However, compared with the progress in the area of mammalian RACK1, our understanding of the functions and molecular mechanisms of RACK1 in the regulation of plant growth and development is still in its infancy. In the present study, we investigated the roles of rice RACK1A gene (OsRACK1A) in controlling seed germination and its molecular mechanisms by generating a series of transgenic rice lines, of which OsRACK1A was either over-expressed or under-expressed. Our results showed that OsRACK1A positively regulated seed germination and negatively regulated the responses of seed germination to both exogenous ABA and H2O2. Inhibition of ABA biosynthesis had no enhancing effect on germination, whereas inhibition of ABA catabolism significantly suppressed germination. ABA inhibition on seed germination was almost fully recovered by exogenous H2O2 treatment. Quantitative analyses showed that endogenous ABA levels were significantly higher and H2O2 levels significantly lower in OsRACK1A-down regulated transgenic lines as compared with those in wildtype or OsRACK1A-up regulated lines. Quantitative real-time PCR analyses showed that the transcript levels of OsRbohs and amylase genes, RAmy1A and RAmy3D, were significantly lower in OsRACK1A-down regulated transgenic lines. It is concluded that OsRACK1A positively regulates seed germination by controlling endogenous levels of ABA and H2O2 and their interaction. PMID:24865690

  4. Development and Validation of a Reversed-Phase Liquid Chromatography Method for the Simultaneous Determination of Indole-3-Acetic Acid, Indole-3-Pyruvic Acid, and Abscisic Acid in Barley (Hordeum vulgare L.

    Directory of Open Access Journals (Sweden)

    Ilva Nakurte

    2012-01-01

     mm I.D with a mobile phase composed of methanol and 1% acetic acid (60 : 40 v/v in isocratic mode at a flow rate of 1 ml min-1. The detection was monitored at 270 nm (ABA and at 282 nm (Ex and 360 nm (Em (IAA, IPA. The developed method was validated in terms of accuracy, precision, linearity, limit of detection, limit of quantification, and robustness. The determined validation parameters are in the commonly acceptable ranges for that kind of analysis.

  5. [Influence of exogenous salicylic acid on the level of phytohormones in tissues of Phlox paniculata and Phlox setacea leaves with special reference to resistance against the powdery mildew causative agent Erysiphe cichoracearum D.C. f. phlogis Jacz].

    Science.gov (United States)

    Talieva, M N; Kondrat'eva, V V

    2002-01-01

    We studied the effects of exogenous salicylic acid on the level of endogenous cytokinins and abscisic and salicylic acids in the tissues of leaves of phloxes contrasting in resistance against the powdery mildew causative agent: susceptible Phlox paniculata L. and resistant Ph. setacea L. Studies were carried out under the conditions of biotic stress. The initial level of salicylic and abscisic acids and cytokinins is the highest in the resistant phlox species. After treatment with salicylic species, the total level of cytokinins and endogenous salicylic acid increased in both species. When the treated phlox species were infected by the powdery mildew causative agent, the level of abscisic and salicylic acids increased in the susceptible Ph. paniculata, while that of cytokinins increased in the resistant Ph. setacea. The role of salicylic acid in the induction of plant defense reactions against phytopathogens is discussed.

  6. Extracorporeal treatment for valproic acid poisoning

    DEFF Research Database (Denmark)

    Ghannoum, Marc; Laliberté, Martin; Nolin, Thomas D

    2015-01-01

    BACKGROUND: The EXtracorporeal TReatments In Poisoning (EXTRIP) workgroup presents its systematic review and clinical recommendations on the use of extracorporeal treatment (ECTR) in valproic acid (VPA) poisoning. METHODS: The lead authors reviewed all of the articles from a systematic literature...... search, extracted the data, summarized the key findings, and proposed structured voting statements following a predetermined format. A two-round modified Delphi method was chosen to reach a consensus on voting statements and the RAND/UCLA Appropriateness Method was used to quantify disagreement....... The workgroup concluded that VPA is moderately dialyzable (level of evidence = B) and made the following recommendations: ECTR is recommended in severe VPA poisoning (1D); recommendations for ECTR include a VPA concentration > 1300 mg/L (9000 μmol/L)(1D), the presence of cerebral edema (1D) or shock (1D...

  7. Lignor process for acidic rock drainage treatment.

    Science.gov (United States)

    Zhuang, J M; Walsh, T

    2004-09-01

    The process using lignosulfonates for acidic rock drainage (ARD) treatment is referred to as the Lignor process. Lignosulfonates are waste by-products produced in the sulfite pulping process. The present study has shown lignosulfonates are able to protect lime from developing an external surface coating, and hence to favor its dissociation. Further, the addition of lignosulfonates to ARD solutions increased the dotting and settling rate of the formed sludge. The capability of lignosulfonates to form stable metal-lignin complexes makes them very useful in retaining metal ions and thus improving the long-term stability of the sludge against leaching. The Lignor process involves metal sorption with lignosulfonates, ARD neutralization by lime to about pH 7, pH adjustment with caustic soda to 9.4 - 9.6, air oxidation to lower the pH to a desired level, and addition of a minimum amount of FeCl3 for further removal of dissolved metals. The Lignor process removes all concerned metals (especially Al and Mn) from the ARD of the Britannia Mine (located at Britannia Beach, British Columbia, Canada) to a level lower than the limits of the B.C. Regulations. Compared with the high-density sludge (HDS) process, the Lignor process has many advantages, such as considerable savings in lime consumption, greatly reduced sludge volume, and improved sludge stability.

  8. Treatment of menorrhagia during menstruation: randomised controlled trial of ethamsylate, mefenamic acid, and tranexamic acid.

    Science.gov (United States)

    Bonnar, J.; Sheppard, B. L.

    1996-01-01

    OBJECTIVE: To compare the efficacy and acceptability of ethamsylate, mefenamic acid, and tranexamic acid for treating menorrhagia. DESIGN: Randomised controlled trial. SETTING: A university department of obstetrics and gynaecology. SUBJECTS: 76 women with dysfunctional uterine bleeding. INTERVENTIONS: Treatment for five days from day 1 of menses during three consecutive menstrual periods. 27 patients were randomised to take ethamsylate 500 mg six hourly, 23 patients to take mefenamic acid 500 mg eight hourly, and 26 patients to take tranexamic acid 1 g six hourly. MAIN OUTCOMES MEASURES: Menstrual loss measured by the alkaline haematin method in three control menstrual periods and three menstrual periods during treatment; duration of bleeding; patient's estimation of blood loss; sanitary towel usage; the occurrence of dysmenorrhoea; and unwanted events. RESULTS: Ethamsylate did not reduce mean menstrual blood loss whereas mefenamic acid reduced blood loss by 20% (mean blood loss 186 ml before treatment, 148 ml during treatment) and tranexamic acid reduced blood loss by 54% (mean blood loss 164 ml before treatment, 75 ml during treatment). Sanitary towel usage was significantly reduced in patients treated with mefenamic acid and tranexamic acid. CONCLUSIONS: Tranexamic acid given during menstruation is a safe and highly effective treatment for excessive bleeding. Patients with dysfunctional uterine bleeding should be offered medical treatment with tranexamic acid before a decision is made about surgery. PMID:8806245

  9. by treatment with crotonic acid and vinyl acetic acid

    Indian Academy of Sciences (India)

    random access memory devices and energy storage devices. Electrolytes, polyelectrolytes or their complexes in ... with alkali-metal salts or metal salts or acids.2,6,7. Measurement of conductivity in solid state shows ..... part and Z sin θ is the imaginary part denoted as Z′ real and. Z′′ imag, respectively. In this way for the ...

  10. Peripheral Amino Acid Levels in Schizophrenia and Antipsychotic Treatment

    OpenAIRE

    De Luca, Vincenzo; Viggiano, Emanuela; Messina, Giovanni; Viggiano, Alessandro; Borlido, Carol; Viggiano, Andrea; Monda, Marcellino

    2008-01-01

    Abnormal levels of amino acids have been reported in patients with schizophrenia and have also been investigated as a biomarker to monitor antipsychotic treatment, however results have been inconsistent. The purpose of the present review is to summarize the evidence in the literature of whether amino acid levels can be a biomarker and predict the treatment outcome in schizophrenia. The current review does not support amino acid concentration as a useful biomarker for monitoring antipsychotic ...

  11. Azelaic acid (15% gel) in the treatment of acne rosacea.

    Science.gov (United States)

    Gupta, Aditya K; Gover, Melissa D

    2007-05-01

    In December of 2002, the FDA approved azelaic acid 15% gel for the topical treatment of inflammatory papules and pustules of mild to moderate rosacea. Azelaic acid is a saturated dicarboxylic acid, which is naturally occurring and has been used in the treatment of rosacea, acne, and melasma. The 15% gel has a high efficacy and is generally well tolerated, with the local irritation (burning, stinging, itching, and scaling) being typically mild and transient. Azelaic acid 15% gel is considered effective and safe as a therapy for inflammatory papulo-pustular rosacea and is suitable for use on all skin types.

  12. Acid mine water aeration and treatment system

    Science.gov (United States)

    Ackman, Terry E.; Place, John M.

    1987-01-01

    An in-line system is provided for treating acid mine drainage which basically comprises the combination of a jet pump (or pumps) and a static mixer. The jet pump entrains air into the acid waste water using a Venturi effect so as to provide aeration of the waste water while further aeration is provided by the helical vanes of the static mixer. A neutralizing agent is injected into the suction chamber of the jet pump and the static mixer is formed by plural sections offset by 90 degrees.

  13. Treatment of Amino Acid Metabolism Disorders

    Science.gov (United States)

    ... of amino acids. Babies with TYR I may need vitamin D, a vitamin that can help babies who ... Rickets is a condition in which too little vitamin D causes a child’s bones to be ... condition, he may need to take certain medicines. For example: Babies with ...

  14. Multifunctional Nucleic Acids for Tumor Cell Treatment

    DEFF Research Database (Denmark)

    Pofahl, Monika; Wengel, Jesper; Mayer, Günter

    2014-01-01

    -proliferative and antimiR function in one 37-nucleotide nucleic acid molecule. It inhibits cancer cell growth and induces gene expression that is pathologically damped by an oncomir. These findings will have a strong impact on future developments regarding aptamer- and antimiR-related applications for tumor targeting...

  15. [Hemoperfusion in the treatment of acute valproic acid intoxication].

    Science.gov (United States)

    Peces, R; Fernández, E J; Sánchez, R J; Peces, C; Montero, A; Selgas, R

    2007-01-01

    Valproic acid is increasingly used in the treatment of epilepsy, and also prescribed for bipolar affective disorders, schizoaffective disorders, schizophrenia and migraine prophylaxis. Valproic acid intoxication with suicide attempt is a relatively common clinical problem that can result in coma, respiratory depression, pancytopenia, hemodynamic instability and death. The drug's relatively low molecular weight, small volume of distribution and saturable protein-binding render it potentially amenable to exracorporeal removal (hemodialysis, hemoperfusion or hemofiltration ), but published experience is scarce. We describe a case report involving valproic acid intoxication with ingestion of ethanol, who was successfully treated with charcoal hemoperfusion. With this treatment the half-life of valproic acid was reduced with rapid lowering of valproic acid levels and clinical improvement. Based on our experience in this patient and a review of previously reported cases, charcoal hemoperfusion should be considered for serious valproic acid intoxication because free as well as bound drug fractions are eliminated via this technique.

  16. 300 Area waste acid treatment system closure plan. Revision 1

    International Nuclear Information System (INIS)

    1996-03-01

    This section provides a description of the Hanford Site, identifies the proposed method of 300 Area Waste Acid Treatment System (WATS) closure, and briefly summarizes the contents of each chapter of this plan

  17. 300 Area waste acid treatment system closure plan. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    This section provides a description of the Hanford Site, identifies the proposed method of 300 Area Waste Acid Treatment System (WATS) closure, and briefly summarizes the contents of each chapter of this plan.

  18. 300 Area waste acid treatment system closure plan

    Energy Technology Data Exchange (ETDEWEB)

    LUKE, S.N.

    1999-05-17

    The Hanford Facility Dangerous Waste Permit Application is considered to be a single application organized into a General Information Portion (document number DOERL-91-28) and a Unit-Specific Portion. The scope of the Unit-Specific Portion includes closure plan documentation submitted for individual, treatment, storage, and/or disposal units undergoing closure, such as the 300 Area Waste Acid Treatment System. Documentation contained in the General Information Portion is broader in nature and could be used by multiple treatment, storage, and/or disposal units (e.g., the glossary provided in the General Information Portion). Whenever appropriate, 300 Area Waste Acid Treatment System documentation makes cross-reference to the General Information Portion, rather than duplicating text. This 300 Area Waste Acid Treatment System Closure Plan (Revision 2) includes a Hanford Facility Dangerous Waste Permit Application, Part A, Form 3. Information provided in this closure plan is current as of April 1999.

  19. 300 Area waste acid treatment system closure plan

    International Nuclear Information System (INIS)

    LUKE, S.N.

    1999-01-01

    The Hanford Facility Dangerous Waste Permit Application is considered to be a single application organized into a General Information Portion (document number DOERL-91-28) and a Unit-Specific Portion. The scope of the Unit-Specific Portion includes closure plan documentation submitted for individual, treatment, storage, and/or disposal units undergoing closure, such as the 300 Area Waste Acid Treatment System. Documentation contained in the General Information Portion is broader in nature and could be used by multiple treatment, storage, and/or disposal units (e.g., the glossary provided in the General Information Portion). Whenever appropriate, 300 Area Waste Acid Treatment System documentation makes cross-reference to the General Information Portion, rather than duplicating text. This 300 Area Waste Acid Treatment System Closure Plan (Revision 2) includes a Hanford Facility Dangerous Waste Permit Application, Part A, Form 3. Information provided in this closure plan is current as of April 1999

  20. Characterization of selectively etched halloysite nanotubes by acid treatment

    Science.gov (United States)

    Garcia-Garcia, Daniel; Ferri, Jose M.; Ripoll, Laura; Hidalgo, Montserrat; Lopez-Martinez, Juan; Balart, Rafael

    2017-11-01

    Halloysite nanotubes (HNTs) are a type of naturally occurring inorganic nanotubes that are characterized by a different composition between their external and internal walls. The internal walls are mainly composed of alumina whilst external walls are composed of silica. This particular structure offers a dual surface chemistry that allows different selective surface treatments which can be focused on increasing the lumen, increasing porosity, etc. In this work, HNTs were chemically treated with different acids (sulphuric, acetic and acrylic acid), for 72 h at a constant temperature of 50 °C. As per the obtained results, the treatment with sulphuric acid is highly aggressive and the particular shape of HNTs is almost lost, with a remarkable increase in porosity. The BET surface area increases from 52.9 (untreated HNTs) up to 132.4 m2 g-1 with sulphuric acid treatment, thus showing an interesting potential in the field of catalysis. On the other hand, the treatment with acetic acid led to milder effects with a noticeable increase in the lumen diameter that changed from 13.8 nm (untreated HNTs) up to 18.4 nm which the subsequent increase in the loading capacity by 77.8%. The aluminium content was measured by X-ray fluorescence (XRF) and laser induced breakdown spectroscopy (LIBS). The final results using two systems, suggest a good correlation between the acid strength and the aluminium reduction. Consequently, is possible to conclude that new applications for HNTs can be derived from selective etching with acids. Sulphuric acid widens the potential of HNTs in the field of catalysis while weak acids such as acetic and acrylic acids give a controlled and homogeneous lumen increase with the corresponding increase in the loading capacity.

  1. Levulinic acid production by two-step acid-catalyzed treatment of Quercus mongolica using dilute sulfuric acid.

    Science.gov (United States)

    Jeong, Hanseob; Jang, Soo-Kyeong; Hong, Chang-Young; Kim, Seon-Hong; Lee, Su-Yeon; Lee, Soo Min; Choi, Joon Weon; Choi, In-Gyu

    2017-02-01

    The objectives of this research were to produce a levulinic acid by two-step acid-catalyzed treatment of Quercus mongolica and to investigate the effect of treatment parameter (reaction temperature range: 100-230°C; sulfuric acid (SA) concentration range: 0-2%) on the levulinic acid yield. After 1 st step acid-catalyzed treatment, most of the hemicellulosic C5 sugars (15.6gg/100gbiomass) were released into the liquid hydrolysate at the reaction temperature of 150°C in 1% SA; the solid fraction, which contained 53.5% of the C6 sugars, was resistant to further loss of C6 sugars. Subsequently, 2 nd step acid-catalyzed treatment of the solid fractions was performed under more severe conditions. Finally, 16.5g/100g biomass of levulinic acid was produced at the reaction temperature of 200°C in 2% SA, corresponding to a higher conversion rate than during single-step treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Azelaic acid 15% gel: in the treatment of papulopustular rosacea.

    Science.gov (United States)

    Frampton, James E; Wagstaff, Antona J

    2004-01-01

    Azelaic acid is a naturally occurring, straight-chain dicarboxylic acid which is effective in the treatment of rosacea, presumably on account of its anti-inflammatory properties. In randomized, double-blind, multicenter studies involving patients with moderate papulopustular facial rosacea, twice-daily topical application of azelaic acid 15% gel to the face was significantly more effective than twice-daily administration of either its vehicle (two studies) or metronidazole 0.75% gel (one study) in reducing inflammatory lesion counts and erythema severity. However, neither active treatment had a clinically discernable effect on telangiectasia. In all three studies, azelaic acid 15% gel recipients experienced continuous decreases in lesion counts and erythema throughout the 12- to 15-week treatment periods. However, the effects of metronidazole 0.75% gel plateauxed after 8 weeks. In other efficacy assessments in these studies, azelaic acid 15% gel was superior to its vehicle and metronidazole 0.75% gel in both the investigators' global assessment of rosacea and the investigators' end-of-study evaluation of overall improvement, and superior to its vehicle in the patients' end-of-study evaluation of overall improvement. The most frequent treatment-related cutaneous adverse events during administration of azelaic acid 15% gel include burning/stinging/tingling and pruritus (itching); however, these events are predominantly transient in nature and mild-to-moderate in intensity.

  3. On the acidity and/or basicity of USY zeolites after basic and acid treatment

    Directory of Open Access Journals (Sweden)

    Calsavara V.

    2000-01-01

    Full Text Available The isopropanol decomposition reaction was used to evaluate the catalytic activity of ultrastable (USY zeolites with different degrees of dealumination, treated in strongly alkaline medium at various temperatures and contact times. This treatment resulted in the reinsertion of non-framework aluminium, a result of the ultrastabilization process. The samples obtained were also submitted to an acid treatment, leaching the non-framework aluminium that had not been reinserted. The results obtained at 723K showed a large reduction in the acidic activity of the alkaline-treated zeolite, as the treatment conditions became more severe (the longer the treatment time or the higher the temperature, the higher the degree of dealumination. On the other hand, treated samples displayed some isopropanol dehydrogenation activity (basic sites. However, this activity was not very significant and did not depend on the alkaline treatment or ultrastabilization conditions used. The effect of reaction temperature and acid leaching on activity is also shown.

  4. Theobromine inhibits uric acid crystallization. A potential application in the treatment of uric acid nephrolithiasis.

    Science.gov (United States)

    Grases, Felix; Rodriguez, Adrian; Costa-Bauza, Antonia

    2014-01-01

    To assess the capacity of methylxanthines (caffeine, theophylline, theobromine and paraxanthine) to inhibit uric acid crystallization, and to evaluate their potential application in the treatment of uric acid nephrolithiasis. The ability of methylxathines to inhibit uric acid nucleation was assayed turbidimetrically. Crystal morphology and its modification due to the effect of theobromine were evaluated by scanning electron microscopy (SEM). The ability of theobromine to inhibit uric acid crystal growth on calculi fragments resulting from extracorporeal shock wave lithotripsy (ESWL) was evaluated using a flow system. The turbidimetric assay showed that among the studied methylxanthines, theobromine could markedly inhibit uric acid nucleation. SEM images showed that the presence of theobromine resulted in thinner uric acid crystals. Furthermore, in a flow system theobromine blocked the regrowth of post-ESWL uric acid calculi fragments. Theobromine, a natural dimethylxanthine present in high amounts in cocoa, acts as an inhibitor of nucleation and crystal growth of uric acid. Therefore, theobromine may be clinically useful in the treatment of uric acid nephrolithiasis.

  5. Theobromine inhibits uric acid crystallization. A potential application in the treatment of uric acid nephrolithiasis.

    Directory of Open Access Journals (Sweden)

    Felix Grases

    Full Text Available To assess the capacity of methylxanthines (caffeine, theophylline, theobromine and paraxanthine to inhibit uric acid crystallization, and to evaluate their potential application in the treatment of uric acid nephrolithiasis.The ability of methylxathines to inhibit uric acid nucleation was assayed turbidimetrically. Crystal morphology and its modification due to the effect of theobromine were evaluated by scanning electron microscopy (SEM. The ability of theobromine to inhibit uric acid crystal growth on calculi fragments resulting from extracorporeal shock wave lithotripsy (ESWL was evaluated using a flow system.The turbidimetric assay showed that among the studied methylxanthines, theobromine could markedly inhibit uric acid nucleation. SEM images showed that the presence of theobromine resulted in thinner uric acid crystals. Furthermore, in a flow system theobromine blocked the regrowth of post-ESWL uric acid calculi fragments.Theobromine, a natural dimethylxanthine present in high amounts in cocoa, acts as an inhibitor of nucleation and crystal growth of uric acid. Therefore, theobromine may be clinically useful in the treatment of uric acid nephrolithiasis.

  6. Theobromine Inhibits Uric Acid Crystallization. A Potential Application in the Treatment of Uric Acid Nephrolithiasis

    Science.gov (United States)

    Grases, Felix; Rodriguez, Adrian; Costa-Bauza, Antonia

    2014-01-01

    Purpose To assess the capacity of methylxanthines (caffeine, theophylline, theobromine and paraxanthine) to inhibit uric acid crystallization, and to evaluate their potential application in the treatment of uric acid nephrolithiasis. Materials and Methods The ability of methylxathines to inhibit uric acid nucleation was assayed turbidimetrically. Crystal morphology and its modification due to the effect of theobromine were evaluated by scanning electron microscopy (SEM). The ability of theobromine to inhibit uric acid crystal growth on calculi fragments resulting from extracorporeal shock wave lithotripsy (ESWL) was evaluated using a flow system. Results The turbidimetric assay showed that among the studied methylxanthines, theobromine could markedly inhibit uric acid nucleation. SEM images showed that the presence of theobromine resulted in thinner uric acid crystals. Furthermore, in a flow system theobromine blocked the regrowth of post-ESWL uric acid calculi fragments. Conclusions Theobromine, a natural dimethylxanthine present in high amounts in cocoa, acts as an inhibitor of nucleation and crystal growth of uric acid. Therefore, theobromine may be clinically useful in the treatment of uric acid nephrolithiasis. PMID:25333633

  7. Azelaic acid in dermatological treatment – current state of knowledge

    Directory of Open Access Journals (Sweden)

    Radomir Reszke

    2016-09-01

    Full Text Available Azelaic acid (AZA is a naturally occurring substance produced by Malassezia furfur which exerts various effects on the skin. Azelaic acid has antibacterial, anti-inflammatory, keratolytic, comedolytic, sebostatic and tyrosinase-inhibiting properties. Topical application of AZA as 20% cream or 15% gel is a well-established therapeutic method in various common dermatoses, mainly acne vulgaris, rosacea and disorders associated with hyperpigmentation. Azelaic acid is used as a component of chemical peels as well. The paper summarizes the most relevant issues concerning AZA application in dermatological treatment based on current knowledge.

  8. Enamel structural changes induced by hydrochloric and phosphoric acid treatment.

    Science.gov (United States)

    Bertacci, Angelica; Lucchese, Alessandra; Taddei, Paola; Gherlone, Enrico F; Chersoni, Stefano

    2014-12-30

    The aim of this study was to evaluate enamel acid-induced structural changes after 2 different treatments, by means of Raman and infrared (IR) spectroscopy analyses, and to correlate these findings with permeability measured as fluid discharge from outer enamel. Two different treatments were investigated: 10 enamel slices were etched with 15% hydrochloric acid (HCl) for 120 seconds and 10 slices with 37% phosphoric acid gel (H3PO4) for 30 seconds, rinsed for 30 seconds and then air-dried for 20 seconds. Powders of enamel treated as previously described were produced. Replicas of enamel subjected to the same treatments were obtained to evaluate the presence of fluid droplets on enamel surface. Raman and IR spectroscopy showed that the treatment with both hydrochloric and phosphoric acids induced a decrease in the carbonate content of the enamel apatite. At the same time, both acids induced the formation of HPO42- ions. After H3PO4 treatment, the bands due to the organic component of enamel decreased in intensity, while they increased after HCl treatment. Replicas of H3PO4 treated enamel showed a strongly reduced permeability. Replicas of HCl 15% treated samples showed a maintained permeability. A decrease of the enamel organic component, as resulted after H3PO4 treatment, involves a decrease in enamel permeability, while the increase of the organic matter (achieved by HCl treatment) still maintains enamel permeability.The results suggested a correlation between organic matter and enamel permeability. Permeability was affected by etching technique and could be involved in marginal seal, gap and discoloration at the enamel interface, still causes of restoration failure.

  9. Comparison the effectiveness of pyruvic acid 50% and salicylic acid 30% in the treatment of acne

    Directory of Open Access Journals (Sweden)

    Fariba Jaffary

    2016-01-01

    Full Text Available Background: Acne vulgaris is a chronic inflammatory disease of the pilosebaceous follicles and one of the most common skin diseases. The peeling method has been recently found to be effective for acne treatment. This study aimed to compare the efficacy of pyruvic acid 50% and salicylic acid 30% peeling in the treatment of mild to moderate acne. Materials and Methods: In a prospective single-blinded clinical trial, 86 patients with acne were randomly assigned into two groups. In both groups, the routine treatment of acne (topical solution of erythromycin 4%, triclorocarban soap, and sunscreen were used twice a day for 8 weeks. In addition, salicylic acid 30% for the control group and pyruvic acid 50% for the case group were used. In both groups, acne severity index (ASI was calculated before and at week 2, 4, 6, and 8 of the treatment. Patient satisfaction was assessed at the end of the treatment. Side effects were recorded using a checklist. Results: In both groups, the reduction in the number of comedones, papules, and ASI were statistically significant (P < 0.001 in the course of treatment. However, it was not significant regarding the number of pustules (P = 0.09. None of the number of comedone, papules, pustules, and ASI was statistically different between study groups. Both treatment groups had similar side effects except for scaling in the fifth session, which was significantly lower in salicylic acid - treated patients (P = 0.015. Conclusion: Both pyruvic acid 50% and salicylic acid 30% are effective in the improvement of mild to moderate acne with no significant difference in efficacy and side effects.

  10. The Evolution of the Treatment of Acid-Related Diseases

    Directory of Open Access Journals (Sweden)

    S.M. Tkach

    2015-11-01

    Full Text Available The article describes the main stages of the development and improvement of antisecretory therapy, from antacids to modern proton pump inhibitors (PPIs. It is concluded that at present the main drugs for the treatment of acid-related diseases are PPIs, which are conditionally divided into drugs of I and II generation. II generation drugs are more effective and safe, as they are less dependent on CYP2C19 polymorphism and have the least potential for side effects and drug-drug interactions. The safest PPI for the long-term treatment of acid-related diseases, especially if it is necessary to administer other drugs, is pantoprazole.

  11. Effect of activated charcoal, abscisic acid and polyethylene glycol on ...

    African Journals Online (AJOL)

    USER

    2010-06-21

    Jun 21, 2010 ... Regeneration in the genus Aesculus via androgenesis. *Corresponding ... Regeneration of this species via androgenesis provides a means of ..... concentration, polyethylene glycol and activated charcoal on maturation and regeneration of Abies cephalonica somatic embryos. Plant Cell Tiss. Organ Cult.

  12. Perioxidases play important roles in abscisic acid (ABA)-simulating ...

    African Journals Online (AJOL)

    Leaf photosynthetic activity limited by summer heat stress represents large constraint to production process of fruit trees. To cope with this problem, we tested photosystem II (PS II) thermostability in clonal apple tree rootstocks with different growth intensity - semi-vigorous-MM106 and dwarfing-J-TE-F experiencing summer ...

  13. Effect of activated charcoal, abscisic acid and polyethylene glycol on ...

    African Journals Online (AJOL)

    USER

    2010-06-21

    Jun 21, 2010 ... Generation of horse chestnut somatic embryos is commonly achieved by transferring embryo- genic tissue onto an ABA, PEG and manitol-containing maturation media (Capuana and Deberg, 1997). Activated charcoal is commonly used in tissue culture media to darken the immediate media surroundings ...

  14. Interactions between ethylene, abscisic acid and cytokinin during ...

    Indian Academy of Sciences (India)

    Santner et al. 2009). Interactions ... Arabidopsis seeds of ecotype Columbia germinate within two days following cold imbibition and transfer to ... ETR1 encodes the ethylene receptor whereas EIN2 encodes a large protein with transmembrane ...

  15. Interactions between ethylene, abscisic acid and cytokinin during ...

    Indian Academy of Sciences (India)

    10 μM N6-benzyl adenine (BA). .... be noted that in a root inhibition assay, eto1-1 was found to show increased resistance to ABA (Ghassemian ... root and hypocotyl elongation in Arabidopsis but does not account for all the action of cytokinins on ...

  16. ABA-alcohol is an intermediate in abscisic acid biosynthesis

    International Nuclear Information System (INIS)

    Rock, C.D.; Zeevaart, J.A.D.

    1990-01-01

    It has been established that ABA-aldehyde is a precursor to ABA. The ABA-deficient flacca and sitiens mutants of tomato are blocked in the conversion of ABA-aldehyde to ABA, and accumulate trans-ABA-alcohol. 18 O-Labeling studies of ABA in flacca and sitiens show that these mutants synthesize a large percentage of [ 18 O]ABA which contains two 18 O atoms in the carboxyl group. Furthermore, the mutants synthesize much greater amounts of trans-ABA-glucose ester (t-ABA-GE) compared with the wild type, and this [ 18 O]t-ABA-GE is also double labeled in the carboxyl group. Our interpretation of these data is that the 18 O in ABA-aldehyde is trapped in the side chain by reduction to [ 18 O]ABA-alcohol, followed by isomerization to [ 18 O]t-ABA-alcohol and oxidation with 18 O 2 to [ 18 O]t-ABA. The [ 18 O]t-ABA is then rapidly converted to [ 18 O]t-ABA-GE. Because [ 18 O]ABA doubly labeled in the carboxyl group has been observed in small amounts in labeling experiments with several species, and various species have been shown to convert ABA-aldehyde to ABA-alcohol and t-ABA-alcohol, we propose that ABA-alcohol is an ABA intermediate in a shunt pathway

  17. WRKY Transcription Factors: Key Components in Abscisic Acid Signaling

    Science.gov (United States)

    2011-01-01

    Sciences, University of Nevada, Las Vegas, NV, USA 3Environmental Laboratory, Engineer Research and Development Center, US Army Corps of Engineers...galactinol synthase (BhGolS1) promoter. Planta , 230, 1155–1166. Wu, F.-Q., Xin, Q., Cao, Z., Liu, Z.-Q., Du, S.-Y., Mei, C., Zhao, C.-X., Wang, X.-F

  18. Treatment of alpha-bearing combustible wastes using acid digestion

    International Nuclear Information System (INIS)

    Lerch, R.E.; Allen, C.R.; Blasewitz, A.G.

    1977-11-01

    Acid digestion has been developed at the Hanford Engineering Development Laboratory (HEDL) in Richland, Washington to reduce the volume of combustible nuclear waste materials, while converting them to an inert, noncombustible residue. A 100 kg/day test unit has recently been constructed to demonstrate the process using radioactively contaminated combustible wastes. The unit, called the Radioactive Acid Digestion Test Unit (RADTU) was completed in September 1977 and is currently undergoing cold shakedown tests. Hot operation is expected in May 1978. Features of RADTU include: storage and transfer station for incoming wastes, a feed preparation station, an extrusion feed mechanism for transfer of the waste to the acid digester, the acid digester, a residue recovery system, and an off-gas treatment system

  19. Effects of Acid treatment on the compression and mechanical ...

    African Journals Online (AJOL)

    This study investigated the effect of acid treatment on the compression and mechanical properties of the cellulosic fibrous residue obtained after a high proportion of starch has been removed from the peeled and rasped tuberous root of Xanthosoma sagittifolium (Family: Araceae). Powdered fibrous residues were subjected ...

  20. Undecylenic acid in the treatment of psoriasis and neurodermatitis.

    Science.gov (United States)

    NELSON, L M

    1951-01-01

    Undecylenic acid in a dosage tolerated by most patients is of doubtful value in the treatment of psoriasis and neurodermatitis.Thirty-one patients were given the drug. Exudative dermatitis developed in one case, generalized pruritus in another. One patient may have had a cardiac accident attributable to the drug.

  1. Fluconazole and boric acid for treatment of vaginal candidiasis- New ...

    African Journals Online (AJOL)

    Objective: To compare boric acid as an effective treatment for VVC compared to fluconazole. We also studied the efficiency of these drugs in preventing recurrence of VVC. Design: A cross sectional, randomized, double-blind study. Settings: Gynaecology clinic of Imam Reza hospital, Tehran - Iran. Subjects: Women with ...

  2. Effects of sulphuric acid and hot water treatments on seed ...

    African Journals Online (AJOL)

    A study was carried out to investigate the effects of sulphuric acid and hot water treatments on the germination of Tamarind (Tamarindus indica L). Seeds were placed on moistened filter papers in 28 cm diameter Petri dishes under laboratory condition for germination. 330 seeds of T. indica (10 seeds per Petri dish) with ...

  3. Ursodeoxycholic Acid and Atorvastatin in the Treatment of Nonalcoholic Steatohepatitis

    Directory of Open Access Journals (Sweden)

    Murat Kiyici

    2003-01-01

    Full Text Available BACKGROUND/AIMS: Nonalcoholic steatohepatitis (NASH is a serious disorder with the potential to gradually progress to cirrhosis. It is generally associated with obesity, diabetes and hyperlipidemia. Currently, there is no established therapy for NASH. The aim of the present study was to evaluate the effectiveness of atorvastatin and ursodeoxycholic acid (UDCA in the treatment of NASH.

  4. The Short-Chain Alcohol Dehydrogenase ABA2 Catalyzes the Conversion of Xanthoxin to Abscisic AldehydeW⃞

    Science.gov (United States)

    González-Guzmán, Miguel; Apostolova, Nadezda; Bellés, José M.; Barrero, José M.; Piqueras, Pedro; Ponce, María R.; Micol, José L.; Serrano, Ramón; Rodríguez, Pedro L.

    2002-01-01

    Mutants able to germinate and perform early growth in medium containing a high NaCl concentration were identified during the course of two independent screenings and named salt resistant (sre) and salobreño (sañ). The sre and sañ mutants also were able to germinate in high-osmoticum medium, indicating that they are osmotolerant in a germination assay. Complementation analyses revealed that sre1-1, sre1-2, sañ3-1, and sañ3-2 were alleles of the abscisic acid (ABA) biosynthesis ABA2 gene. A map-based cloning strategy allowed the identification of the ABA2 gene and molecular characterization of four new aba2 alleles. The ABA2 gene product belongs to the family of short-chain dehydrogenases/reductases, which are known to be NAD- or NADP-dependent oxidoreductases. Recombinant ABA2 protein produced in Escherichia coli exhibits a Km value for xanthoxin of 19 μM and catalyzes in a NAD-dependent manner the conversion of xanthoxin to abscisic aldehyde, as determined by HPLC–mass spectrometry. The ABA2 mRNA is expressed constitutively in all plant organs examined and is not upregulated in response to osmotic stress. The results of this work are discussed in the context of previous genetic and biochemical evidence regarding ABA biosynthesis, confirming the xanthoxin→abscisic aldehyde→ABA transition as the last steps of the major ABA biosynthetic pathway. PMID:12172025

  5. Structural-phase transformations in bentonite after acid treatment

    Directory of Open Access Journals (Sweden)

    Vlasova M.

    2003-01-01

    Full Text Available The methods of X-ray diffraction, Fourier transform infra-red spectroscopy (FTIR, X-ray microanalysis, electron microscopy, BET and cation exchange capacity (CEC were used for investigation of the structural-phase transformations in bentonite under the influence of hydrochloric acid and temperature treatment (100-800ºC. It is established that in HCl medium during temperature treatment, dehydration and dehydroxilation of montmorillonite occur. The presence of gypsum and barium chloride results in an intercalation of interlayer space of montmorillonite by Ca and Ba ions Temperature treatment of intercalated montmorillonite leads to the formation of pores.

  6. Azelaic acid 15% gel in the treatment of rosacea.

    Science.gov (United States)

    Gollnick, Harald; Layton, Alison

    2008-10-01

    Rosacea represents a chronic inflammatory dermatosis of uncertain pathophysiology. There are several associated risk factors and the need for long-term treatment is well recognized. This diverse disease is frequently difficult to manage and has a significant impact on quality of life. There are several topical and oral treatments available, of which azelaic acid 15% gel (Finacea) is the first new treatment for rosacea in more than a decade. Azelaic acid per se has multiple modes of action in rosacea, but an anti-inflammatory effect achieved by reducing reactive oxygen species appears to be the main pharmacological action. Clinical studies have shown that azelaic acid 15% gel is an effective and safe first-line topical therapeutic option in patients with mild-to-moderate papulopustular rosacea. Significant continuous improvement in the number of inflammatory lesions and in erythema has been shown over a period of 15 weeks. Adverse effects associated with azelaic acid 15% gel are mostly mild or transient and do not usually necessitate discontinuation of therapy.

  7. Neridronic acid for the treatment of bone metabolic diseases.

    Science.gov (United States)

    Gatti, Davide; Viapiana, Ombretta; Idolazzi, Luca; Fracassi, Elena; Adami, Silvano

    2009-10-01

    Neridronic acid (6-amino-1-idroxyesilidene-1,1-bisphosphonate) is a nitrogen-containing bisphosphonate licensed in Italy for the treatment of osteogenesis imperfecta and Paget's disease of bone. The pharmacodynamic profile is similar to that of other nitrogen-containing bisphosphonates and is characterized by its high affinity for bone tissue particularly at sites undergoing a process of remodeling. In growing children affected by osteogenesis imperfect, neridronic acid rapidly increases bone mineral density as measured by dual X-ray absortiometry and this is associated with a significant decrease in fracture cumulative number. Similar results have been obtained also in newborns ( 75% of bone turnover markers) in 95% of the patients. Neridronic acid treatment has been reported to be effective also in other skeletal diseases such as osteoporosis, algodystrophy, hypercalcemia of malignancy and bone metastasis. Neridronic acid has been developed only for parenteral use, and it is the only one used as intramuscular injection. This avoids all the limitations of oral bisphosphonates and may be offered for a home treatment with simple nursing assistance.

  8. Bile acid malabsorption in chronic diarrhea: pathophysiology and treatment.

    Science.gov (United States)

    Barkun, Alan N; Love, Jonathan; Gould, Michael; Pluta, Henryk; Steinhart, Hillary

    2013-11-01

    Bile acid malabsorption (BAM) is a common but frequently under-recognized cause of chronic diarrhea, with an estimated prevalence of 4% to 5%. The published literature for the period 1965 to 2012 was examined for articles regarding the pathophysiology and treatment of BAM to provide an overview of the management of BAM in gastroenterology practice. BAM is classified as type 1 (secondary to ileal dysfunction), type 2 (idiopathic) or type 3 (secondary to gastrointestinal disorders not associated with ileal dysfunction). The estimated prevalence of BAM is >90% in patients with resected Crohn disease (CD) and 11% to 52% of unresected CD patients (type 1); 33% in diarrhea-predominant irritable bowel syndrome (type 2); and is a frequent finding postcholecystectomy or postvagotomy (type 3). Investigations include BAM fecal bile acid assay, 23-seleno-25-homo-tauro-cholic acid (SeHCAT) testing and high-performance liquid chromatography of serum 7-α-OH-4-cholesten-3-one (C4), to determine the level of bile acid synthesis. A less time-consuming and expensive alternative in practice is an empirical trial of the bile acid sequestering agent cholestyramine. An estimated 70% to 96% of chronic diarrhea patients with BAM respond to short-course cholestyramine. Adverse effects include constipation, nausea, borborygmi, flatulence, bloating and abdominal pain. Other bile acid sequestering agents, such as colestipol and colesevelam, are currently being investigated for the treatment of BAM-associated diarrhea. BAM is a common cause of chronic diarrhea presenting in gastroenterology practice. In accordance with current guidelines, an empirical trial of a bile acid sequestering agent is warranted as part of the clinical workup to rule out BAM.

  9. Role of acidic chemistries in steam treatment of aluminium alloys

    DEFF Research Database (Denmark)

    Din, Rameez Ud; Jellesen, Morten Stendahl; Ambat, Rajan

    2015-01-01

    The effect of acidic chemistry on the accelerated growth of oxide on aluminium alloys Peraluman 706TM and AA6060 under exposure to high temperature steam was investigated. Studied chemistries were based on citrates and phosphates. Results showed that the presence of citrate and phosphate anions...... initiate doxide growth at the intermetallic particles while growth and corrosion performance of oxide was found tobe a function of anions type and their concentration. Further, steam treatment with phosphates exhibited better performance under acetic acid salt spray and filiform corrosion test whereas...

  10. Polysialic acid bioengineering of neuronal cells by N-acyl sialic acid precursor treatment.

    Science.gov (United States)

    Pon, Robert A; Biggs, Nancy J; Jennings, Harold J

    2007-03-01

    The inherent promiscuity of the polysialic acid (PSA) biosynthetic pathway has been exploited by the use of exogenous unnatural sialic acid precursor molecules to introduce unnatural modifications into cellular PSA, and has found applications in nervous system development and tumor vaccine studies. The sialic acid precursor molecules N-propionyl- and N-butanoyl-mannosamine (ManPr, ManBu) have been variably reported to affect PSA biosynthesis ranging from complete inhibition to de novo production of modified PSA, thus illustrating the need for further investigation into their effects. In this study, we have used a monoclonal antibody (mAb) 13D9, specific to both N-propionyl-PSA and N-butanoyl-PSA (NPrPSA and NBuPSA), together with flow cytometry, to study precursor-treated tumor cells and NT2 neurons at different stages of their maturation. We report that both ManPr and ManBu sialic acid precursors are metabolized and the resultant unnatural sialic acids are incorporated into de novo surface sialylglycoconjugates in murine and human tumor cells and, for the first time, in human NT2 neurons. Furthermore, neither precursor treatment deleteriously affected endogenous PSA expression; however, with NT2 cells, PSA levels were naturally downregulated as a function of their maturation into polarized neurons independent of sialic acid precursor treatment.

  11. Hyaluronidase offers an efficacious treatment for inaesthetic hyaluronic acid overcorrection.

    Science.gov (United States)

    Pierre, Andre; Levy, Phillip M

    2007-09-01

    Hyaluronic acid is generally accepted today as the "gold standard" filler agent, and its use has subsequently grown enormously. In addition, newer facial volume augmentation indications are constantly evolving. Rare adverse events, such as granulomas, have been described. However, complications are more commonly due to product misplacement or overcorrection leading to unsightly lumps and masses. Hyaluronidase treatment of these latter adverse effects can be both effective and rapid. This paper aims to confirm the efficacy of hyaluronidase injections in dissolving unsightly hyaluronic acid overcorrection. A case of hyaluronic acid overcorrection is described with evaluation of the effects of hyaluronidase. The use of hyaluronidase, injected intracutaneously permits the elimination of patient discomfort and inaesthetic lumps within a few hours. Hyaluronidase is highly effective in eliminating HA volume overcorrection.

  12. Using simulated wetlands to assess acid mine drainage treatment efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Karathanasis, A.D. (Kentucky University, Lexington, KY (USA). Dept. of Agronomy)

    1992-01-01

    The elevated acidity and increased solubility of toxic metals such as Al, Fe, Mn, Cu, and Zn associated with acid mine drainage (AMD) is causing increasing concern about possible toxic effects to plants, aquatic life, animals, and even humans in the coal regions of the Appalachian states. During the last few years, a new technology for treatment of acid mine discharges has emerged. The technology involves the construction of artificial wetlands with dominant vegetation [ital Typha] (cattails), [ital Sphagnum] (moss), certain algae, and other plant species which have the potential to treat small flows of acid mine water moving through them. Greenhouse experiments at the University of Kentucky involving AMD treatment by surface and subsurface flow simulated wetlands with [ital Typha] plants (cattails) grown in six different substrates showed significant differences among substrates in their ability to buffer mine drainage acidity and in metal removal efficiency. Of the six substrates tested, the pine-needle-and-hay mixtures were the most efficient over the peat, sphagnum moss and mine spoil mixtures in reducing acidity and Al, Cu and Zn concentrations in surface effluents. The majority of the substrates (except the mine spoil surface soil) showed similar efficiencies for Fe removal, but all substrates were a source rather than a sink for Mn in surface and subsurface flows. The results of this study suggest that short-term screenings of various substrate materials under greenhouse conditions such as those used in this investigation may provide useful information on the selection of the most efficient substrate for the metal(s) of interest and thus, help improve the performance of the wetland under construction. 2 figs.

  13. Removal of coagulant aluminum from water treatment residuals by acid.

    Science.gov (United States)

    Okuda, Tetsuji; Nishijima, Wataru; Sugimoto, Mayo; Saka, Naoyuki; Nakai, Satoshi; Tanabe, Kazuyasu; Ito, Junki; Takenaka, Kenji; Okada, Mitsumasa

    2014-09-01

    Sediment sludge during coagulation and sedimentation in drinking water treatment is called "water treatment residuals (WTR)". Polyaluminum chloride (PAC) is mainly used as a coagulant in Japan. The recycling of WTR has been desired; one method for its reuse is as plowed soil. However, WTR reuse in this way is inhibited by the aluminum from the added PAC, because of its high adsorption capacity for phosphate and other fertilizer components. The removal of such aluminum from WTR would therefore be advantageous for its reuse as plowed soil; this research clarified the effect of acid washing on aluminum removal from WTR and on plant growth in the treated soil. The percentage of aluminum removal from raw WTR by sulphuric acid solution was around 90% at pH 3, the percentage decreasing to 40% in the case of a sun-dried sample. The maximum phosphate adsorption capacity was decreased and the available phosphorus was increased by acid washing, with 90% of aluminum removal. The enhancement of Japanese mustard spinach growth and the increased in plant uptake of phosphates following acid washing were observed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Organising pneumonia associated with fumaric acid ester treatment for psoriasis.

    LENUS (Irish Health Repository)

    Deegan, Alexander Paul

    2012-02-01

    INTRODUCTION: We present the case of a 49-year old male who presented with dyspnoea, cough, weight loss, night sweats and general malaise. He had been on treatment with oral fumaric acid esters (FAE, Fumaderm(R); Biogen Idec GmbH, Ismaning, Germany) for 6 months. METHODS: Report of a case. RESULTS: His chest X-ray showed patchy infiltrates in the left upper lobe which failed to resolve under empiric antibiotic therapy. A computed tomography of thorax revealed bilateral, mostly peripheral foci of consolidation with air bronchograms. Transbronchial biopsies showed a pattern of organising pneumonia (OP). CONCLUSIONS: Therapy with oral prednisolone (40 mg\\/day) resulted in a rapid clinical and radiological improvement. An association of FAE and OP has not previously been reported. Please cite this paper as: Deegan AP, Kirby B, Rogers S, Crotty TB and McDonnell TJ. Organising pneumonia associated with fumaric acid ester treatment for psoriasis.

  15. Silica Content and Structure from Corncob Ash with Various Acid Treatment (HCl, HBr, and Citric Acid

    Directory of Open Access Journals (Sweden)

    Gladys Ayu Paramita Kusumah Wardhani

    2017-11-01

    Full Text Available In this study, a simple method to obtain silica from corncob ash has been investigated using a nonthermal and thermal method. The Nonthermal method was done by various acid treatment with HCl, HBr and citric acid at room temperature. Thermal method was performed for HCl-leached, HBr-leached, and citric acid-leached corncob in the furnace at 750 ºC for 5 hours. Corncob ash was characterized by Energy Dispersive X-ray fluorescence spectroscopy (EDXRF, Fourier transforms infrared spectroscopy (FTIR, X-Ray diffraction (XRD, and Scanning electron microscope-electron dispersive X-ray (SEM-EDX. In this study silica content increase after acid treatment (leaching and combustion at high temperatures. The result established that silica is most obtained with HCl treatment that is equal to 79,95% with lower metallic oxide impurity content. The FTIR spectra with different intensity shows silanol group at 1636 – 1641 cm-1, whereas siloxane group at 1037 – 1106 cm-1, 616–797 cm-1, and 459–469 cm-1. X-Ray diffractogram shows silica transition pf amorphous (2θ = 21 - 25º to quartz crystalline (2θ = 26.66º phase. The surface morphology of silica that characterized with SEM-EDX shows amorphous and crystalline silica corresponds to XRD result. The high intensity spectra of Si and O in EDX shows the presence of silica in corncob ash.

  16. Effect of Omega-3 Fatty Acids Treatment on Insulin Resistance

    Directory of Open Access Journals (Sweden)

    Mogoş Tiberius

    2014-12-01

    Full Text Available Background and aims: Insulin resistance (IR is a common pathogenic factor of several diseases: diabetes mellitus, the metabolic syndrome, arterial hypertension, atherosclerosis, dyslipidemia, etc. There are many therapeutic factors involved in decreasing IR. Among them we mention metformin, pioglitazone, physical activity, weight loss, diet, etc. In the last decade, there are more observations of the influence of polyunsaturated fatty acids on IR. The most powerful seem to be omega-3 fatty acids. In our study, we wanted to asses if the administration of omega-3 fatty acids is involved in modifying IR. Materials and methods: We evaluated 126 diabetic patients with IR from January 2011 until July 2014. The study was open-label and non-randomized. For the determination of IR we used the HOMA-IR method. Results: For both males and females there was a regression of HOMA-IR during the 4 weeks of treatment with omega-3 and also after 2 weeks after stopping the administration of these fatty acids. The decrease of HOMA-IR was statistically significant (p<0.05. The statistic result observed in the next 2 weeks after stopping administration of omega-3 was also significant (p<0.05.

  17. Response of Abies alba embryonal-suspensor mass to various carbohydrate treatments.

    Science.gov (United States)

    Schuller, A; Reuther, G

    1993-02-01

    Cultures of embryonal-suspensor mass of European silver fir (Abies alba) were screened for their response to various sucrose concentrations (29-175 mM) and to equimolar (100 or 200 mM) concentrations of glucose, fructose, galactose, sucrose, lactose and soluble starch. The higher concentrations were combined with 3.78 μM abscisic acid. While fructose was ineffective in promoting any somatic embryo maturation glucose, sucrose and galactose promoted early maturation stages. Somatic embryo development up to the torpedo stage was observed only on media with soluble starch or lactose. Lactose was superior to other carbohydrate treatments and led to more synchronized maturation and more normally structured embryos. In comparison with the pronounced carbohydrate effect abscisic acid at this concentration proved to be of less importance. A sequence of culture steps was established in order to stimulate differentiation and maturation.

  18. The treatments of soil Rirang by floatation and Acid leaching

    International Nuclear Information System (INIS)

    Kosim-Affandi; Umar-Sarip; Alwi, Guswita; Sri-Sudaryanto

    2000-01-01

    The treatments of soil Rirang by floatation and acid leaching has been carried out to increase high uranium concentrates of materials, separating associated economical minerals and to reduce the gangue minerals which bothering at chemical processing. The physical treatment has been done by ore preparation and floatation using oleic acid and p ine oil , 20 % of pulp at pH 9, condition time at 5 minutes and collections of float fraction was 10 minutes. The chemical processing has been done by dynamic leaching using H 2 SO 4 100 kg/ton, MnO 2 20 kg/ton, 50 % of solid with ore size - 65 mesh, temperature at 80 o C and time of leaching was 8 hours. The result of experiments is as follows : Physical treatment by floatation shown that the concentrates of U increased at sink fraction by (1.5 - 2) times against feed sample for all the samples, and in the float fraction the recovery of molybdenite separation is 58 - 81 % and rare earths is 57 - 80 %. The result of dynamic leaching is 76 - 91 %, and recovery uranium increasing from 81.02 % (mixture samples soil before floatation) to 91.16 % ( mixture samples of float fraction)

  19. Proteasome inhibitor treatment reduced fatty acid, triacylglycerol and cholesterol synthesis.

    Science.gov (United States)

    Oliva, Joan; French, Samuel W; Li, Jun; Bardag-Gorce, Fawzia

    2012-08-01

    In the present study, the beneficial effects of proteasome inhibitor treatment in reducing ethanol-induced steatosis were investigated. A microarray analysis was performed on the liver of rats injected with PS-341 (Bortezomib, Velcade), and the results showed that proteasome inhibitor treatment significantly reduced the mRNA expression of SREBP-1c, and the downstream lipogenic enzymes, such as fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC), which catalyzes the carboxylation of acetyl-CoA to malonyl-CoA, the rate-limiting step in fatty acid synthesis. ELOVL6, which is responsible for fatty acids long chain elongation, was also significantly downregulated by proteasome inhibitor treatment. Moreover, PS-341 administration significantly reduced the expression of acyl-glycerol-3-phosphate acyltransferase (AGPAT), and diacylglycerol acyltransferase (DGAT), enzyme involved in triacylglycerol (TAG) synthesis. Finally, PS-341 was found to downregulate the enzyme 3-hydroxy-3-methylglutaryl-CoenzymeA synthase (HMG-CoA synthase) that is responsible for cholesterol synthesis. Proteasome inhibitor was also found to play a role in intestinal lipid adsorption because apolipoproteins A (apoA-I, apoAII, apoA-IV and ApoCIII) were downregulated by proteasome inhibitor treatment, especially ApoA-II that is known to be a marker of alcohol consumption. Proteasome inhibitor treatment also decreased apobec-1 complementation factor (ACF) leading to lower level of editing and production of ApoB protein. Moreover apolipoprotein C-III, a major component of chylomicrons was significantly downregulated. However, lipoprotein lipase (Lpl) and High density lipoprotein binding protein (Hdlbp) mRNA levels were increased by proteasome inhibitor treatment. These results suggested that proteasome inhibitor treatment could be used to reduce the alcohol-enhanced lipogenesis and alcohol-induced liver steatosis. A morphologic analysis, performed on the liver of rats fed ethanol for one month and

  20. Treatment of Hallux Valgus with Hyaluronic Acid: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Ižlhan Sezer

    2017-05-01

    Full Text Available Aim: Hallux valgus is the deformity of the first metatarsophalangeal (MTP joint with abduction and valgus rotation of the great toe, combined with a medially prominent first metatarsal head. Hyaluronic acid injection has been used in the treatment of degenerative disorders of several joints successfully. In this research, we aimed to investigate the effectiveness of hyaluronic acid injection in patients with hallux valgus. Material and Method: Eleven female and two male patients with hallux valgus were included in this pilot study. Only patients with mild and moderate hallux valgus were included in the study. 1 cc hyaluronic acid was injected into the affected MTF joint three times, at one-week intervals. Visual analogue scale(VAS score, walking time without pain, walking distance, and daily analgesic needs of the patients were recorded. All clinical outcomes were assessed before, and then one and three months after the first injection. Results:The mean VAS score was 83.08±4.58. One month after the first injection, VAS scores of patients had decreased significantly (30±4.38, P: 0.001. Also, increased walking time and distance and decreased daily analgesic need were observed at the first month of postinjection follow-up (P: 0.001. After 3 months, the positive outcomes remained significant compared to preinjection evaluations. Discussion: According to our preliminary results, we suggest thathyaluronic acid injectionsmay be effective in reducing pain and increasing walking time and distance in patients with hallux valgus.Future studies are needed to clarify the beneficial effects of hyaluronic acid injection in patients with hallux valgus.

  1. Retinoic acid and glycolic acid combination in the treatment of acne scars

    Directory of Open Access Journals (Sweden)

    B S Chandrashekar

    2015-01-01

    Full Text Available Introduction: Acne is a prevalent condition in society affecting nearly 80-90% of adolescents often resulting in secondary damage in the form of scarring. Retinoic acid (RA is said to improve acne scars and reduce postinflammatory hyperpigmentation while glycolic acid (GA is known for its keratolytic properties and its ability to reduce atrophic acne scars. There are studies exploring the combined effect of retinaldehyde and GA combination with positive results while the efficacy of retinoic acid and GA (RAGA combination remains unexplored. Aim: The aim of this study remains to retrospectively assess the efficacy of RAGA combination on acne scars in patients previously treated for active acne. Materials and Methods: A retrospective assessment of 35 patients using topical RAGA combination on acne scars was done. The subjects were 17-34 years old and previously treated for active acne. Case records and photographs of each patient were assessed and the acne scars were graded as per Goodman and Baron′s global scarring grading system (GSGS, before the start and after 12 weeks of RAGA treatment. The differences in the scar grades were noted to assess the improvement. Results: At the end of 12 weeks, significant improvement in acne scars was noticed in 91.4% of the patients. Conclusion: The RAGA combination shows efficacy in treating acne scars in the majority of patients, minimizing the need of procedural treatment for acne scars.

  2. Acid Water Neutralization Using Microbial Fuel Cells: An Alternative for Acid Mine Drainage Treatment

    Directory of Open Access Journals (Sweden)

    Eduardo Leiva

    2016-11-01

    Full Text Available Acid mine drainage (AMD is a complex environmental problem, which has adverse effects on surface and ground waters due to low pH, high toxic metals, and dissolved salts. New bioremediation approach based on microbial fuel cells (MFC can be a novel and sustainable alternative for AMD treatment. We studied the potential of MFC for acidic synthetic water treatment through pH neutralization in batch-mode and continuous-flow operation. We observed a marked pH increase, from ~3.7 to ~7.9 under batch conditions and to ~5.8 under continuous-flow operation. Likewise, batch reactors (non-MFC inoculated with different MFC-enriched biofilms showed a very similar pH increase, suggesting that the neutralization observed for batch operation was due to a synergistic influence of these communities. These preliminary results support the idea of using MFC technologies for AMD remediation, which could help to reduce costs associated with conventional technologies. Advances in this configuration could even be extrapolated to the recovery of heavy metals by precipitation or adsorption processes due to the acid neutralization.

  3. Intralesional hyaluronic acid: an innovative treatment for Peyronie's disease.

    Science.gov (United States)

    Gennaro, Romano; Barletta, Davide; Paulis, Gianni

    2015-10-01

    The significantly different effects of several conservative treatments for Peyronie's disease (PD) led us to conduct this study to evaluate the effectiveness of local treatment with injectable hyaluronic acid (HA) for patients with this disease. The study included 83 PD patients who underwent treatment and 81 PD patients who did not (control group). The inclusion criteria were: penile plaque volume <1 cm(3); clinical characteristics and ultrasonographic appearance compatible with active inflammation; and penile curvature <45°. The medical history of all PD patients was collected. Patients undertook six tests: routine laboratory tests; penile auto-photography during erection; dynamic penile colour-duplex ultrasound study; penile X-ray (mammography technique); index of erectile function questionnaire (IIEF); and pain intensity questionnaire (visual analog scale). Treated patients received thirty penile infiltrations by injection of 20 mg HA in 6 months. Follow-up checks were conducted at the end of treatment and 12 and 24 months after treatment. At 12-month follow-up all treated PD patients had experienced three statistically significant outcomes: reduction in plaque size (-93.7 %, p < 0.0001); improvement in penile curvature (-9.01°, p < 0.0001); and improvement in penile rigidity (mean IIEF score +3.8) with an average increase of 21.1 % (p < 0.0001). Furthermore, the improvements remained substantially stable at 24-month follow-up. Considering the minimally invasive approach in this study, the absence of major side effects, and the significant treatment outcomes achieved, we conclude that intralesional penile injections with HA are effective for treating Peyronie's disease.

  4. Hepatic arachidonic acid metabolism is disrupted after hexachlorobenzene treatment

    International Nuclear Information System (INIS)

    Billi de Catabbi, Silvia C.; Faletti, Alicia; Fuentes, Federico; San Martin de Viale, Leonor C.; Cochon, Adriana C.

    2005-01-01

    Hexaclorobenzene (HCB), one of the most persistent environmental pollutants, can cause a wide range of toxic effects including cancer in animals, and hepatotoxicity and porphyria both in humans and animals. In the present study, liver microsomal cytochrome P450 (CYP)-dependent arachidonic acid (AA) metabolism, hepatic PGE production, and cytosolic phospholipase A 2 (cPLA 2 ) activity were investigated in an experimental model of porphyria cutanea tarda induced by HCB. Female Wistar rats were treated with a single daily dose of HCB (100 mg kg -1 body weight) for 5 days and were sacrificed 3, 10, 17, and 52 days after the last dose. HCB treatment induced the accumulation of hepatic porhyrins from day 17 and increased the activities of liver ethoxyresorufin O-deethylase (EROD), methoxyresorufin O-demethylase (MROD), and aminopyrine N-demethylase (APND) from day 3 after the last dose. Liver microsomes from control and HCB-treated rats generated, in the presence of NADPH, hydroxyeicosatetraenoic acids (HETEs), epoxyeicosatrienoic acids (EETs), 11,12-Di HETE, and ω-OH/ω-1-OH AA. HCB treatment caused an increase in total NADPH CYP-dependent AA metabolism, with a higher response at 3 days after the last HCB dose than at the other time points studied. In addition, HCB treatment markedly enhanced PGE production and release in liver slices. This HCB effect was time dependent and reached its highest level after 10 days. At this time cPLA 2 activity was shown to be increased. Unexpectedly, HCB produced a significant decrease in cPLA 2 activity on the 17th and 52nd day. Our results demonstrated for the first time that HCB induces both the cyclooxygenase and CYP-dependent AA metabolism. The effects of HCB on AA metabolism were previous to the onset of a marked porphyria and might contribute to different aspects of HCB-induced liver toxicity such as alterations of membrane fluidity and membrane-bound protein function. Observations also suggested that a possible role of cPLA 2 in

  5. Solid Lipid Nanoparticles Loaded with Retinoic Acid and Lauric Acid as an Alternative for Topical Treatment of Acne Vulgaris.

    Science.gov (United States)

    Silva, Elton Luiz; Carneiro, Guilherme; De Araújo, Lidiane Advíncula; Trindade, Mariana de Jesus Vaz; Yoshida, Maria Irene; Oréfice, Rodrigo Lambert; Farias, Luis de Macêdo; De Carvalho, Maria Auxiliadora Roque; Dos Santos, Simone Gonçalves; Goulart, Gisele Assis Castro; Alves, Ricardo José; Ferreira, Lucas Antônio Miranda

    2015-01-01

    Topical therapy is the first choice for the treatment of mild to moderate acne and all-trans retinoic acid is one of the most used drugs. The combination of retinoids and antimicrobials is an innovative approach for acne therapy. Recently, lauric acid, a saturated fatty acid, has shown strong antimicrobial activity against Propionibacterium acnes. However, topical application of retinoic acid is followed by high incidence of side-effects, including erythema and irritation. Solid lipid nanoparticles represent an alternative to overcome these side-effects. This work aims to develop solid lipid nanoparticles loaded with retinoic acid and lauric acid and evaluate their antibacterial activity. The influence of lipophilic stearylamine on the characteristics of solid lipid nanoparticles was investigated. Solid lipid nanoparticles were characterized for size, zeta potential, encapsulation efficiency, differential scanning calorimetry and X-ray diffraction. The in vitro inhibitory activity of retinoic acid-lauric acid-loaded solid lipid nanoparticles was evaluated against Propionibacterium acnes, Staphylococcus aureus and Staphylococcus epidermidis. High encapsulation efficiency was obtained at initial time (94 ± 7% and 100 ± 4% for retinoic acid and lauric acid, respectively) and it was demonstrated that lauric acid-loaded-solid lipid nanoparticles provided the incorporation of retinoic acid. However, the presence of stearylamine is necessary to ensure stability of encapsulation. Moreover, retinoic acid-lauric acid-loaded solid lipid nanoparticles showed growth inhibitory activity against Staphylococcus epidermidis, Propionibacterium acnes and Staphylococcus aureus, representing an interesting alternative for the topical therapy of acne vulgaris.

  6. The 300 area waste acid treatment system closure plan

    International Nuclear Information System (INIS)

    Luke, S.N.

    1996-01-01

    The 300 Area Waste Acid Treatment System (WATS) is located within operable units 300-FF-2 (source) and 300-FF-5 (groundwater), as designated in the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) . Operable units 300-FF-2 and 300-FF-5 are scheduled to be remediated using the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) Remedial Investigation/Feasibility Study (RI/FS) process. Thus, any remediation of the 300 Area WATS with respect to contaminants not produced by those facilities and soils and groundwater will be deferred to the CERCLA RI/FS process. Final closure activities will be completed in 3 phases and certified in accordance with the 300 Area WATS closure plan by the Washington State Department of Ecology (Ecology) and the U.S. Environmental Protection Agency (EPA). It is anticipated that the 300 Area WATS closure would take 2 years to complete

  7. Functionalization of carbon nanotube yarn by acid treatment

    Directory of Open Access Journals (Sweden)

    H.E. Misak

    2014-01-01

    Full Text Available Carbon nanotube (CNT yarn was functionalized using sulfuric and nitric acid solutions in 3:1 volumetric ratio. Successful functionalization of CNT yarn with carboxyl and hydroxyl groups (e.g., COOH, COO–, OH, etc. was confirmed by attenuated total reflectance spectroscopy. X-ray diffraction revealed no significant change to the atomic in-plane alignment in the CNTs; however, the coherent length along the diameter was significantly reduced during functionalization. A morphology change of wavy extensions protruding from the surface was observed after the functionalization treatment. The force required to fracture the yarn remained the same after the functionalization process; however, the linear density was increased (310%. The increase in linear density after functionalization reduced the tenacity. However, the resistivity density product of the CNT yarn was reduced significantly (234% after functionalization.

  8. Diameter sensitive effect in singlewalled carbon nanotubes upon acid treatment

    International Nuclear Information System (INIS)

    Costa, S.; Borowiak-Palen, E.

    2009-01-01

    Singlewalled carbon nanotubes (SWCNT) exhibit very unique properties. As an electronic system they undergo amphoteric doping effects (n-type and p-type) which can be reversed. These processes affect the optical and vibronic properties of the carbon nanotubes. The most common and widely used procedure which changes the properties of the SWCNT is acid treatment applied as a purification procedure. This effect has been widely studied but not fully understood so far. Here, we present a study, in which a diameter sensitive effect has been observed. Therefore, two kinds of SWCNT samples have been studied: (i) produced via chemical vapour deposition with a broad diameter distribution, and (ii) synthesised by the laser ablation technique which is commonly known to result in narrow diameter distribution bulk SWCNT samples. Resonance Raman spectroscopy, optical absorption spectroscopy, and Fourier transform middle-infrared spectroscopy have been applied for the characterisation of the samples.

  9. The Comparison of Hydrochloric Acid and Phosphoric Acid Treatments in the Preparation of Montmorillonite Catalysts for RNA Synthesis

    Science.gov (United States)

    Aldersley, Michael Frank; Joshi, Prakash C.; Huang, Yixing

    2017-09-01

    The treatment of clay minerals with a preliminary acid wash and titration to pH 7 has proven to generate catalysts for the most interesting of oligomerization reactions in which activated RNA-nucleotides generate oligomers up to 40-mers. Significantly, not all clay minerals become catalytic following this treatment and none are catalytic in the absence of such treatment. The washing procedure has been modified and explored further using phosphoric acid and the outcomes are compared to those obtained when clay samples are prepared following a hydrochloric acid wash.

  10. The Comparison of Hydrochloric Acid and Phosphoric Acid Treatments in the Preparation of Montmorillonite Catalysts for RNA Synthesis.

    Science.gov (United States)

    Aldersley, Michael Frank; Joshi, Prakash C; Huang, Yixing

    2017-09-01

    The treatment of clay minerals with a preliminary acid wash and titration to pH 7 has proven to generate catalysts for the most interesting of oligomerization reactions in which activated RNA-nucleotides generate oligomers up to 40-mers. Significantly, not all clay minerals become catalytic following this treatment and none are catalytic in the absence of such treatment. The washing procedure has been modified and explored further using phosphoric acid and the outcomes are compared to those obtained when clay samples are prepared following a hydrochloric acid wash.

  11. Hyaluronic acid covers in burn treatment: a systematic review.

    Science.gov (United States)

    Dalmedico, Michel Marcos; Meier, Marineli Joaquim; Felix, Jorge Vinícius Cestari; Pott, Franciele Soares; Petz, Francislene de Fátima Cordeiro; Santos, Michelle Caroline

    2016-01-01

    To evaluate the effectiveness of hyaluronic acid in the healing of partial thickness burns. Systematic review of randomized controlled trials on the use of hyaluronic acid for the topical treatment of skin burns, based on recommendations of the Cochrane Handbook for Systematic Reviews of Interventions. Two randomized controlled trials that analyzed 143 patients with partial thickness burns and/or deep partial thickness burns were selected. They compared the application of hyaluronic acid 0.2% associated to silver sulfadiazine 1% 5g/cm2 versus silver sulfadiazine 1% 5g/cm2 alone for the outcome of complete healing. This review emphasizes the need for new well-designed randomized controlled trials to establish the therapeutic relevance of hyaluronic acid with respect to the healing of burns of partial thickness or deep partial thickness. Avaliar a efetividade do ácido hialurônico na cicatrização de queimaduras de espessura parcial. Revisão sistemática de ensaios clínicos randomizados sobre a utilização de ácido hialurônico no tratamento tópico de queimaduras de pele, baseada nas recomendações do Cochrane Handbook for Systematic Reviews of Interventions. Foram recuperados dois ensaios clínicos randomizados que analisaram 143 pacientes portadores de queimaduras de espessura parcial e/ou espessura parcial profunda, comparando a aplicação de Ácido Hialurônico 0,2% associado à Sulfadiazina de Prata 1% 5g/cm2, versus Sulfadiazina de Prata 1% 5g/cm2 isolada, para o desfecho cicatrização completa. Esta revisão enfatiza a necessidade de novos ensaios clínicos randomizados bem delineados para estabelecimento da relevância terapêutica do ácido hialurônico no que tange à cicatrização de queimaduras de espessura parcial ou espessura parcial profunda.

  12. Effect of Short Term Salicylic Acid and Ascorbic Acid Treatments on Delaying Flowers’ Senescence of Cut Rose Cv. Red Naomy

    Directory of Open Access Journals (Sweden)

    H. Samady

    2015-01-01

    Full Text Available This experiment was conducted on rose cut flowers, Red Naomy cultivar, with the length of 35 cm, for 18 hours as a short-term treatment in a factorial based on completely randomized design with five treatments including sucrose + 8-Hydroxyquinoline sulfate, salicylic acid + sucrose + 8-Hydroxyquinoline sulfate, ascorbic acid + sucrose + 8-Hydroxyquinoline sulfate, Salicylic acid + ascorbic acid + sucrose‌ + 8-Hydroxyquinoline sulfate and distilled water as control, and three replications in bottles. Morphological traits such as shelf life, changes in water uptake, fresh weight, flower diameter and physiological traits such as total protein and proline contents were measured. The results showed that combination of Salicylic acid + sucrose + 8-Hydroxyquinoline sulfate treatment significantly affected shelf life compared to control and other treatments. The results also revealed that the combination of Salicylic acid + ascorbic acid + sucrose‌ + 8-Hydroxyquinoline sulfate delayed flowers senescence and increased the amount of water uptake, fresh weight and flower diameter. Moreover, the greatest protein and proline contents were obtained under ascorbic acid + sucrose + 8-Hydroxyquinoline sulfate treatment and sucrose + 8-Hydroxyquinoline sulfate, respectively.

  13. EVALUATION OF SUGARCANE BAGASSE ACID HYDROLYZATE TREATMENTS FOR XYLITOL PRODUCTION

    Directory of Open Access Journals (Sweden)

    P.V. GURGEL

    1998-09-01

    Full Text Available Acid sugarcane bagasse hydrolyzate was submitted to pH shifts in order to remove toxic compounds from the medium. The hydrolyzate was treated with bases containing mono-, di- or tri-valent cations and H2SO4, and its performance as a fermentation medium was evaluated by the production of xylitol by Candida guilliermondii FTI 20037. The use of bases containing mono-valent cations was not an efficient method of detoxification, and the use of a tri-valent cation did not show any detectable improvement in detoxification. The treated hydrolyzate recovery (in volume is greatly affected by the utilized base. Treatment using Al(OH3 and NaOH showed the best hydrolyzate recovery (87.5%, while the others presented a recovery of about 45% of the original hydrolyzate volume. Considering the whole process, best results were achieved by treatment using Al(OH3 and NaOH which allowed 0.55 g of xylitol produced from each gram of xylose in the raw hydrolyzate.

  14. Evaluation of the efficacy and safety of combinations of hydroquinone, glycolic acid, and hyaluronic acid in the treatment of melasma.

    Science.gov (United States)

    Ibrahim, Zeinab A; Gheida, Shereen F; El Maghraby, Gamal M; Farag, Zeinab E

    2015-06-01

    Various treatments are currently available for melasma. However, results are often disappointing. 1 To assess the efficacy and safety of combinations of hydroquinone, glycolic acid, and hyaluronic acid in the treatment of melasma after topical application. 2 To evaluate the dermoscopy as a tool in diagnosis and follow-up of melasma treatment. One hundred patients with mild, moderate-to-severe melasma were divided into five groups. Group I (twenty patients were treated with cream formula containing 4% hydroquinone), group II (twenty patients were treated with cream formula containing 4% hydroquinone + 10% glycolic acid), group III (twenty patients were treated with cream formula containing 4% hydroquinone + 0.01% hyaluronic acid), group IV (twenty patients were treated with cream formula containing 4% hydroquinone + 10% glycolic acid + 0.01% hyaluronic acid), and group V (twenty patients were treated with placebo cream). All patients were subjected to dermoscopic examination and digital photographs before and after treatment. The response and side effects were evaluated. Groups I, III, and IV showed highly significant changes in modified Melasma Area and Severity Index (mMASI) score after using the treatment. Group II showed significant change in mMASI score after using the treatment. The side effects were more reported in group II, followed by group IV, followed by group I, followed by group III. There was highly significant difference between the dermoscopic color findings before and after treatment. Vascularization was another dermoscopic finding. A cream formula containing 4% hydroquinone + 10% glycolic acid + 0.01% hyaluronic acid was very effective in treatment of melasma with tolerable side effects. Dermoscope is a valuable noninvasive tool in the diagnosis and follow-up of melasma treatment. © 2015 Wiley Periodicals, Inc.

  15. Comparative study of trichloroacetic acid versus glycolic acid chemical peels in the treatment of melasma

    Directory of Open Access Journals (Sweden)

    Kumari Rashmi

    2010-01-01

    Full Text Available Background: Melasma is a common cause of facial hyperpigmentation with significant cosmetic deformity. Many modalities of treatment are available, but none is satisfactory. Aim: This study was designed to compare the therapeutic response of melasma in Indian women to glycolic acid (GA 20-35% versus trichloroacetic acid (TCA 10-20% for chemical peeling. Methods: Forty nonpregnant female patients with a minimum melasma area and severity index (MASI of 10 were recruited in the study. After a detailed history and clinical examination under natural light, MASI was calculated and color photographs were taken of all the patients. The patients were advised to carry out a prepeel program of daily application of 12% GA cream or 0.1% tretinoin at night for 2 weeks. They were then treated with graded concentrations of 20-35% GA facial peel every 15 days in GA group and 10-20% TCA in the second group. Results: Objective response to treatment evaluated by reduction in MASI scoring after 12 weeks was by 79% reduction (from 26.6 to 5.6 in GA group and by 73% reduction in TCA group (from 29.1 to 8.2 but this difference was not significant. Patients with epidermal-type melasma showed a better response to treatment than those with mixed-type melasma (P < 0.05. Subjective response, as graded by the patient, showed good or very good response in 75% in GA group and 65% in TCA group. No relation of treatment response to age and duration of melasma could be established in this study. Conclusions: A prepeel program of daily application of 12% GA cream at night for 2 weeks, followed by graded increase in GA and TCA concentrations proved to be an equally effective treatment modality for epidermal and mixed melasma. There are hardly any major side effects, and regular use of sunscreens prevents chances of postpeel hyperpigmentation. GA peel is associated with fewer side effects than TCA and has the added advantage of facial rejuvenation.

  16. Bioelectrochemical treatment of acid mine drainage dominated with iron

    International Nuclear Information System (INIS)

    Lefebvre, Olivier; Neculita, Carmen M.; Yue, Xiaodi; Ng, How Yong

    2012-01-01

    Highlights: ► Treatment of AMD dominated with Fe is problematic due to its low pH. ► The goal of AMD treatment is pH increasing and Fe controlled removal. ► An MFC could fulfill both these requirements by treating AMD at the aerated cathode. ► The performance was proportional to the charge transfer up to 880 C. ► The treated AMD met the discharge limits both for Fe (>99% recovery) and pH (7.9). - Abstract: Treatment of acid mine drainage (AMD) dominated with iron (Fe), the most common metal, is a long-term expensive commitment, the goal of which is to increase the pH and remove Fe. In the present study, a proton exchange membrane microbial fuel cell (MFC) showed promise for the efficient treatment of an AMD dominated with ferric iron (pH 2.4 ± 0.1; 500 mg L −1 Fe 3+ ). Briefly, Fe 3+ was reduced to Fe 2+ at the cathode of the MFC, followed by Fe 2+ re-oxidation and precipitation as oxy(hydroxi)des. Oxygen reduction and cation transfer to the cathode of the MFC further caused a rise in pH. A linear relationship was observed between the charge transferred in the MFC and the performance of the system up to 880 C. Optimal conditions were found at a charge of 662 C, achieved within 7 d at an acetate concentration of 1.6 g L −1 in a membrane MFC. This caused the pH to rise to 7.9 and resulted in a Fe removal of 99%. Treated effluent met the pH discharge limits of 6.5–9. The maximum power generation achieved under these conditions averaged 8.6 ± 2.3 W m −3 , which could help reduce the costs of full-scale bioelectrochemical treatment of AMD dominated with Fe.

  17. Exogenous treatment with indole-3-acetic acid and salicylic acid alleviates cadmium toxicity in wheat seedlings.

    Science.gov (United States)

    Agami, Ramadan A; Mohamed, Gamal F

    2013-08-01

    The seedlings of wheat were grown in the presence of CdCl2 (500 or 1000 μM Cd), were applied with 500 μM of indole-3-acetic acid (IAA) or 500 μM salicylic acid (SA) as seed soaking and were sampled at 56 days after sowing. The plants exposed to Cd exhibited a substantial decline in growth, pigment content, relative water content (RWC) activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POX) and leaf structure. However, pretreatment with IAA or SA mitigated the stress generated by Cd and markedly improved the aforesaid parameters. The Cd increased proline content, electrolyte leakage and plant Cd content. However, the IAA or SA treatment attenuated the adverse effects of Cd on these attributes. The results showed that pretreatment with IAA or SA enhanced the antioxidant defense activities in Cd stressed wheat, thus alleviating Cd induced oxidative damage and enhancing Cd tolerance and leaf anatomy. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Treatments of acid waters; Tratamientos pasivos de aguas acidas

    Energy Technology Data Exchange (ETDEWEB)

    Delgado Fernandez, J. L.

    2000-07-01

    The exploitation of coal mining locations causes acid effluents due to the oxidation of the sulfurous minerals content of the rocks, denominated acid waters. There are Pyritic materials, pyres and sulphates associated to acid waters that in presence of water, oxygen and certain bacteria (mainly Thiobacillus ferro oxidants), are oxidized, by means of a chemistry reaction, yielding different products. (Author)

  19. Salicylic-acid-mediated enhanced biological treatment of wastewater.

    Science.gov (United States)

    Khardenavis, Anshuman A; Kapley, Atya; Purohit, Hemant J

    2010-03-01

    Activated sludge represents a microbial community which is responsible for reduction in pollution load from wastewaters and whose performance depends upon the composition and the expression of degradative capacity. In the present study, the role of salicylic acid (SA) has been evaluated for acclimatization of activated sludge collected from a combined effluent treatment plant followed by analysis of the physiological performance and microbial community of the sludge. The biodegradative capacity of the acclimatized activated sludge was further evaluated for improvement in efficiency of chemical oxygen demand (COD) removal from wastewater samples collected from industries manufacturing bulk drugs and dyes and dye intermediates (wastewater 1) and from dye industry (wastewater 2). An increase in COD removal efficiency from 50% to 58% and from 78% to 82% was observed for wastewater 1 and wastewater 2, respectively. Microbial community analysis data showed selective enrichment and change in composition due to acclimatization by SA, with 50% of the clones showing sequence homology to unidentified and uncultured bacteria. This was demonstrated by analysis of partial 16S rDNA sequence data generated from dominating clones representing the metagenome which also showed the appearance of a unique population of clones after acclimatization, which was distinct from those obtained before acclimatization and clustered away from the dominating population.

  20. The use of hydrated lime in acid mine drainage treatment

    Science.gov (United States)

    Othman, Anuar; Sulaiman, Azli; Sulaiman, Shamsul Kamal

    2017-05-01

    Hydrated lime also known as calcium hydroxide with chemical formula Ca(OH)2 was used in this study as neutralization agent in acid mine drainage (AMD) treatment. Hydrated lime that is used to treat pool water samples from tin tailings located in Pengkalan Hulu, Perak was obtained from Simpang Pulai, Perak. The pH of water sample was around 2.6 to 2.8. Ten different variables of hydrated lime weights were used to treat 1 L of water sample. The weights of hydrated lime used were 0.2 g, 0.4 g, 0.6 g, 0.8 g, 1.0 g, 1.2 g, 1.4 g, 1.6 g, 1.8 g and 2.0 g. Time interval used was every 5 minutes up to minutes 30. Jar test method was used in this study. The maximum pH value of 5.93 ± 0.03 most approaches standard A and had complied standard B have been obtained using 2.0 g hydrated lime in 30-minute time interval. The concentration of arsenic, cadmium and chromium had decreased but only cadmium concentration did not comply with Standards A and B.

  1. Hydrothermal-acid treatment for effectual extraction of eicosapentaenoic acid (EPA)-abundant lipids from Nannochloropsis salina.

    Science.gov (United States)

    Lee, Ilgyu; Han, Jong-In

    2015-09-01

    Hydrothermal acid treatment, was adopted to extract eicosapentaenoic acid (EPA) from wet biomass of Nannochloropsis salina. It was found that sulfuric acid-based treatment increased EPA yield from 11.8 to 58.1 mg/g cell in a way that was nearly proportional to its concentration. Nitric acid exhibited the same pattern at low concentrations, but unlike sulfuric acid its effectiveness unexpectedly dropped from 0.5% to 2.0%. The optimal and minimal conditions for hydrothermal acid pretreatment were determined using a statistical approach; its maximum EPA yield (predicted: 43.69 mg/g cell; experimental: 43.93 mg/g cell) was established at a condition of 1.27% of sulfuric acid, 113.34 °C of temperature, and 36.71 min of reaction time. Our work demonstrated that the acid-catalyzed cell disruption, accompanied by heat, can be one potentially promising option for ω-3 fatty acids extraction. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Ursodeoxycholic acid and atorvastatin in the treatment of nonalcoholic steatohepatitis.

    Science.gov (United States)

    Kiyici, Murat; Gulten, Macit; Gurel, Selim; Nak, Selim Giray; Dolar, Enver; Savci, Gursel; Adim, Saduman Balaban; Yerci, Omer; Memik, Faruk

    2003-12-01

    Nonalcoholic steatohepatitis (NASH) is a serious disorder with the potential to gradually progress to cirrhosis. It is generally associated with obesity, diabetes and hyperlipidemia. Currently, there is no established therapy for NASH. The aim of the present study was to evaluate the effectiveness of atorvastatin and ursodeoxycholic acid (UDCA) in the treatment of NASH. This prospective study included 44 adult patients (24 men, 20 women) with a mean age of 48.90+/-7.69 years and mean body mass index (BMI) of 29.40+/-3.82. Ten patients had a history of diabetes. Serological markers for viral hepatitis were negative in all patients and there was no history of alcohol or drug abuse. Patients who had autoimmune hepatitis were excluded from the study. Liver biopsy was performed before therapy to confirm the diagnosis. Among NASH patients, 17 normolipidemic cases received UDCA 13 to 15 mg/kg/day (group 1), while hyperlipidemic cases (n=27) received atorvastatin 10 mg/day (group 2) for six months. The BMI, serum lipids, liver function tests and liver density, assessed by computerized tomography, were evaluated before and after the treatment period. The BMI, serum aminotransferase levels, histological parameters (steatosis, inflammation, fibrosis scores) and liver densities were not statistically different between the groups at the beginning of therapy. The BMI, serum glucose, and triglyceride levels did not change in either group after the treatment period. In group 1, serum alanine aminotransferase (ALT) and gamma-glutamyl-transferase (GGT) levels reduced significantly, and in group 2, serum cholesterol, aspartate aminotransferase, ALT, alkaline phosphatase and GGT levels reduced significantly. Liver densities increased only in group 2, probably as a result of diminishing fat content of liver. The normalization of transaminases was also more prevalent in group 2. Liver steatosis was closely correlated with liver density, but inflammation and fibrosis were not. The use of

  3. Azelaic acid in dermatological treatment – current state of knowledge

    OpenAIRE

    Radomir Reszke; Jacek Szepietowski

    2016-01-01

    Azelaic acid (AZA) is a naturally occurring substance produced by Malassezia furfur which exerts various effects on the skin. Azelaic acid has antibacterial, anti-inflammatory, keratolytic, comedolytic, sebostatic and tyrosinase-inhibiting properties. Topical application of AZA as 20% cream or 15% gel is a well-established therapeutic method in various common dermatoses, mainly acne vulgaris, rosacea and disorders associated with hyperpigmentation. Azelaic acid is used as a component of chemi...

  4. Case Report: Valproic Acid and Risperidone Treatment Leading to Development of Hyperammonemia and Mania

    Science.gov (United States)

    Carlson, Teri; Reynolds, Charles A.; Caplan, Rochelle

    2007-01-01

    This case report describes two children who developed hyperammonemia together with frank manic behavior during treatment with a combination of valproic acid and risperidone. One child had been maintained on valproic acid for years and risperidone was added. In the second case, valproic acid was introduced to a child who had been treated with…

  5. Oxic limestone drains for treatment of dilute, acidic mine drainage

    Science.gov (United States)

    Cravotta, Charles A.

    1998-01-01

    Limestone treatment systems can be effective for remediation of acidic mine drainage (AMD) that contains moderate concentrations of dissolved O2 , Fe3+ , or A13+ (1‐5 mg‐L‐1 ). Samples of water and limestone were collected periodically for 1 year at inflow, outflow, and intermediate points within underground, oxic limestone drains (OLDs) in Pennsylvania to evaluate the transport of dissolved metals and the effect of pH and Fe‐ and Al‐hydrolysis products on the rate of limestone dissolution. The influent was acidic and relatively dilute (pH 1 mg‐L‐1 ) but was near neutral (pH = 6.2‐7.0); Fe and Al decreased to less than 5% of influent concentrations. As pH increased near the inflow, hydrous Fe and Al oxides precipitated in the OLDs. The hydrous oxides, nominally Fe(OH)3 and AI(OH)3, were visible as loosely bound, orange‐yellow coatings on limestone near the inflow. As time elapsed, Fe(OH)3 and AI(OH)3 particles were transported downflow. During the first 6 months of the experiment, Mn 2+ was transported conservatively through the OLDs; however, during the second 6 months, concentrations of Mn in effluent decreased by about 50% relative to influent. The accumulation of hydrous oxides and elevated pH (>5) in the downflow part of the OLDs promoted sorption and coprecipitation of Mn as indicated by its enrichment relative to Fe in hydrous‐oxide particles and coatings on limestone. Despite thick (~1 mm) hydrous‐oxide coatings on limestone near the inflow, CaCO3 dissolution was more rapid near the inflow than at downflow points within the OLD where the limestone was not coated. The rate of limestone dissolution decreased with increased residence time, pH, and concentrations of Ca2+ and HCO3‐ and decreased PCO2. The following overall reaction shows alkalinity as an ultimate product of the iron hydrolysis reaction in an OLD:Fe2+ + 0.25 O2 +CaCO3 + 2.5 H2O --> Fe(OH)3 + 2 Ca2+ + 2 HCO3-where 2 moles of CaCO3 dissolve for each mole of Fe(OH)3 produced

  6. Randomized clinical trial of ascorbic acid in the treatment of pressure ulcers

    NARCIS (Netherlands)

    ter Riet, G.; Kessels, A. G.; Knipschild, P. G.

    1995-01-01

    The objective of this study was to assess the effects of ascorbic acid supplementation, 500 mg twice daily in the treatment of pressure ulcers as an adjunct to standardized treatment. The design consisted of a multicenter blinded randomized trial. The control group received 10 mg of ascorbic acid

  7. Treatment and prevention systems for acid mine drainage and halogenated contaminants

    Science.gov (United States)

    Jin, Song [Fort Collins, CO; Fallgren, Paul H [Laramie, WY; Morris, Jeffrey M [Laramie, WY

    2012-01-31

    Embodiments include treatments for acid mine drainage generation sources (10 perhaps by injection of at least one substrate (11) and biologically constructing a protective biofilm (13) on acid mine drainage generation source materials (14). Further embodiments include treatments for degradation of contaminated water environments (17) with substrates such as returned milk and the like.

  8. PASSIVE TREATMENT OF ACID ROCK DRAINAGE FROM A SUBSURFACE MINE

    Science.gov (United States)

    Acidic, metal-contaminated drainages are a critical problem facing many areas of the world. Acid rock drainage results when metal sulfide minerals, particularly pyrite, are oxidized by exposure to oxygen and water. The deleterious effects of these drainages on receiving streams a...

  9. Treatment of Irradiated Mice with High-Dose Ascorbic Acid Reduced Lethality

    Science.gov (United States)

    Sato, Tomohito; Kinoshita, Manabu; Yamamoto, Tetsuo; Ito, Masataka; Nishida, Takafumi; Takeuchi, Masaru; Saitoh, Daizoh; Seki, Shuhji; Mukai, Yasuo

    2015-01-01

    Ascorbic acid is an effective antioxidant and free radical scavenger. Therefore, it is expected that ascorbic acid should act as a radioprotectant. We investigated the effects of post-radiation treatment with ascorbic acid on mouse survival. Mice received whole body irradiation (WBI) followed by intraperitoneal administration of ascorbic acid. Administration of 3 g/kg of ascorbic acid immediately after exposure significantly increased mouse survival after WBI at 7 to 8 Gy. However, administration of less than 3 g/kg of ascorbic acid was ineffective, and 4 or more g/kg was harmful to the mice. Post-exposure treatment with 3 g/kg of ascorbic acid reduced radiation-induced apoptosis in bone marrow cells and restored hematopoietic function. Treatment with ascorbic acid (3 g/kg) up to 24 h (1, 6, 12, or 24 h) after WBI at 7.5 Gy effectively improved mouse survival; however, treatments beyond 36 h were ineffective. Two treatments with ascorbic acid (1.5 g/kg × 2, immediately and 24 h after radiation, 3 g/kg in total) also improved mouse survival after WBI at 7.5 Gy, accompanied with suppression of radiation-induced free radical metabolites. In conclusion, administration of high-dose ascorbic acid might reduce radiation lethality in mice even after exposure. PMID:25651298

  10. Production of Valuables Organic Acids from Organic Wastes with Hydrothermal Treatment Process

    Directory of Open Access Journals (Sweden)

    Muhammad Faisal

    2009-06-01

    Full Text Available This article reports production of valuables organic acids from the hydrothermal treatment of representative organic wastes and compounds (i. e. domestic sludge, proteinaceous, cellulosic and plastic wastes with or without oxidant (H2O2. Organic acids such as acetic, formic, propionic, succinic and lactic acids were obtained in significant amounts. At 623 K (16.5 MPa, acetic acid of about 26 mg/g-dry waste fish entrails was obtained. This increased to 42 mg/g dry waste fish entrails in the presence of H2O2. Experiments on glucose to represent cellulosic wastes were also carried out, getting acetic acid of about 29 mg/g-glucose. The study was extended to terephthalic acid and glyceraldehyde, reaction intermediates of hydrothermal treatment of PET plastic wastes and glucose, respectively. Studies on temperature dependence of formation of organic acids showed thermal stability of acetic acid, whereas, formic acid decomposed readily under hydrothermal conditions. In general, results demonstrated that the presence of oxidants favored formation of organic acids with acetic acid being the major product. Keywords: hydrothermal treatment, organic acids, organic wastes, oxidant, supercritical water oxidation

  11. Solution of Azelaic Acid (20%, Resorcinol (10% and Phytic Acid (6% Versus Glycolic Acid (50% Peeling Agent in the Treatment of Female Patients with Facial Melasma

    Directory of Open Access Journals (Sweden)

    Gita Faghihi

    2017-01-01

    Full Text Available Background: Melasma, a common acquired disorder of hyperpigmentation, especially in women, is often resistant to therapy. This study was aimed to evaluate the efficacy and safety of azelaic acid, resorcinol and phytic acid solution in chemical peeling of melasma in comparison to 50% glycolic acid. Materials and Methods: This clinical trial was performed, on 42 female patients with bilateral melasma. Severity of melasma was assessed by melasma area and severity index (MASI. Combination of (20% azelaic acid + 10% resorcinol + 6% phytic acid was used as a new peeling agent on the right side of the face and 50% glycolic acid on the left side every 2 weeks for 6 times. Follow-up was carried out for 3 months after the last session. Any decrease in MASI score and unwanted complications following peeling were evaluated and compared during the trial. Results: Patients showed marked improvement as calculated with MASI score before and after treatment in both sides of the face. The efficacy of combination formula (azelaic acid, resorcinol and phytic acid was similar to glycolic acid, but with fewer complications. There was no statistically difference in improvement between two groups (P > 0.05. However, the patient's discomfort following procedures was significantly lower with azelaic acid, resorcinol and phytic compared with the glycolic acid peels (P < 0.05 and there was the same duration in the beginning of the therapeutic response in both groups. Conclusion: Results showed that triple-combination was found to be an effective and safe peeling agent in the treatment of melasma and it was as effective as 50% glycolic acid peel.

  12. Solution of Azelaic Acid (20%), Resorcinol (10%) and Phytic Acid (6%) Versus Glycolic Acid (50%) Peeling Agent in the Treatment of Female Patients with Facial Melasma.

    Science.gov (United States)

    Faghihi, Gita; Taheri, Azam; Shahmoradi, Zabihollah; Nilforoushzadeh, Mohammad Ali

    2017-01-01

    Melasma, a common acquired disorder of hyperpigmentation, especially in women, is often resistant to therapy. This study was aimed to evaluate the efficacy and safety of azelaic acid, resorcinol and phytic acid solution in chemical peeling of melasma in comparison to 50% glycolic acid. This clinical trial was performed, on 42 female patients with bilateral melasma. Severity of melasma was assessed by melasma area and severity index (MASI). Combination of (20% azelaic acid + 10% resorcinol + 6% phytic acid) was used as a new peeling agent on the right side of the face and 50% glycolic acid on the left side every 2 weeks for 6 times. Follow-up was carried out for 3 months after the last session. Any decrease in MASI score and unwanted complications following peeling were evaluated and compared during the trial. Patients showed marked improvement as calculated with MASI score before and after treatment in both sides of the face. The efficacy of combination formula (azelaic acid, resorcinol and phytic acid) was similar to glycolic acid, but with fewer complications. There was no statistically difference in improvement between two groups ( P > 0.05). However, the patient's discomfort following procedures was significantly lower with azelaic acid, resorcinol and phytic compared with the glycolic acid peels ( P < 0.05) and there was the same duration in the beginning of the therapeutic response in both groups. Results showed that triple-combination was found to be an effective and safe peeling agent in the treatment of melasma and it was as effective as 50% glycolic acid peel.

  13. Effects of pre-treatments with abscisic acid and/or benzyladenine on gas exchange of French bean, sugar beet, and maize leaves during water stress and after rehydration

    Czech Academy of Sciences Publication Activity Database

    Pospíšilová, Jana; Baťková, P.

    2004-01-01

    Roč. 48, č. 3 (2004), s. 395-399 ISSN 0006-3134 R&D Projects: GA ČR GA522/02/1099 Institutional research plan: CEZ:AV0Z5038910 Keywords : Beta vulgaris * net photosynthetic rate * Phaseolus vulgaris Subject RIV: ED - Physiology Impact factor: 0.744, year: 2004

  14. Effect of acidic treatment on carbon nano tubes for immobilization of cellulase enzyme

    International Nuclear Information System (INIS)

    Al-Khatib, M.F.R.; Mohd Zahangir Alam; Rasha Mohammed

    2009-01-01

    Full text: The effect of acidic treatment on MWCNTs functionalization was studied by mixing different ratios (1:1, 1:2, and 1:3 v/v %) of nitric acid and sulphuric acid, respectively. The effect of these treatments on the structure of MWCNTs was characterized by Fourier transform infrared spectroscopy (FTIR) and Filed emission scanning electron microscopy (FESEM). Results showed that the optimum ratio 1:3 (v/v %) is best suitable in imparting carboxylic acid and hydroxyl groups which are required for immobilization of cellulase enzyme on functionalized CNTs. (author)

  15. Acid-digestion treatment of plutonium-containing waste

    International Nuclear Information System (INIS)

    Wieczorek, H.; Kemmler, G.; Krause, H.

    1981-01-01

    The Radioactive Acid-Digestion Test Unit (RADTU) has been constructed at Hanford to demonstrate the application of the acid-digestion process for treating combustible transuranic wastes and scrap materials. The RADTU, with its original tray digestion vessel, has recently completed a six-month campaign processing potentially contaminated non-glovebox wastes from a Hanford plutonium facility. During this campaign, it processed 2100 kg largely cellulosic wastes at an average sustained processing rate of 3 kg/h as limited by the acid-waste contact and the water boil-off rate from the acid feeds. The on-line operating efficiency was nearly 50% on a twelve-hour day, five-day week basis. Following this campaign, a new annular high-rate digester has been installed for testing. In preliminary tests with simulated wastes, the new digester demonstrated a sustained capacity of 10 kg/h with greatly improved intimacy of contact between the digestion acid and the waste. The new design also doubles the heat-transfer surface, which is expected to provide at least twice the water boil-off rate of the previous tray digester design. Following shakedown testing with simulated and low-level wastes, the new unit will be used to process combustible plutonium scrap and waste from Hanford plutonium facilities for the purposes of volume reduction, plutonium recovery, and stabilization of the final waste form. (author)

  16. Oxidative acid treatment and characterization of new biocarbon from sustainable Miscanthus biomass

    Energy Technology Data Exchange (ETDEWEB)

    Anstey, Andrew [Bioproducts Discovery and Development Centre (BDDC), Department of Plant Agriculture, Crop Science Building, University of Guelph, Guelph, ON N1G 2W1 (Canada); School of Engineering, Thornbrough Building, University of Guelph, Guelph, ON N1G 2W1 (Canada); Vivekanandhan, Singaravelu [Bioproducts Discovery and Development Centre (BDDC), Department of Plant Agriculture, Crop Science Building, University of Guelph, Guelph, ON N1G 2W1 (Canada); Sustainable Materials and Nanotechnology Lab, Department of Physics, VHNSN College, Virudhunagar 626 001, Tamilnadu (India); Rodriguez-Uribe, Arturo [Bioproducts Discovery and Development Centre (BDDC), Department of Plant Agriculture, Crop Science Building, University of Guelph, Guelph, ON N1G 2W1 (Canada); Misra, Manjusri [Bioproducts Discovery and Development Centre (BDDC), Department of Plant Agriculture, Crop Science Building, University of Guelph, Guelph, ON N1G 2W1 (Canada); School of Engineering, Thornbrough Building, University of Guelph, Guelph, ON N1G 2W1 (Canada); Mohanty, Amar Kumar, E-mail: mohanty@uoguelph.ca [Bioproducts Discovery and Development Centre (BDDC), Department of Plant Agriculture, Crop Science Building, University of Guelph, Guelph, ON N1G 2W1 (Canada); School of Engineering, Thornbrough Building, University of Guelph, Guelph, ON N1G 2W1 (Canada)

    2016-04-15

    Oxidative acid treatments of biochar produced from Miscanthus were performed in this study using nitric acid, sulfuric acid, and a mixture of both. The structural and morphological changes of the acid-treated biochar were investigated using Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), Raman spectroscopy, organic elemental analysis and energy-dispersive X-ray spectroscopy (EDS). Improved surface functionality of the treated biochars was observed in their respective FT-IR spectra through the presence of nitro and carboxylic acid functional groups. SEM–EDS and elemental analysis revealed a large increase in the oxygen to carbon ratio in the biochar, which was evidence of chemical oxidation from the acid treatment. Further, TGA study showed the reduced thermal stability of acid-treated biochar over 200 °C due to the increased oxygen content. Acid treatments also influenced the graphitic structure of the biochar, as observed in the Raman spectra. The results suggest that biochar can be successfully functionalized for composite applications and provide a sustainable alternative to petroleum-based carbon additives. - Highlights: • Biochar was investigated as a candidate for renewable functionalized carbon. • Oxidative acid treatment was used to modify the carbon structure. • The chemical and morphological properties of the treated biochar were examined. • Successful chemical modification of biochar was verified through characterization. • Biochar shows potential as a sustainable carbon additive for polymer composites.

  17. Oxidative acid treatment and characterization of new biocarbon from sustainable Miscanthus biomass

    International Nuclear Information System (INIS)

    Anstey, Andrew; Vivekanandhan, Singaravelu; Rodriguez-Uribe, Arturo; Misra, Manjusri; Mohanty, Amar Kumar

    2016-01-01

    Oxidative acid treatments of biochar produced from Miscanthus were performed in this study using nitric acid, sulfuric acid, and a mixture of both. The structural and morphological changes of the acid-treated biochar were investigated using Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), Raman spectroscopy, organic elemental analysis and energy-dispersive X-ray spectroscopy (EDS). Improved surface functionality of the treated biochars was observed in their respective FT-IR spectra through the presence of nitro and carboxylic acid functional groups. SEM–EDS and elemental analysis revealed a large increase in the oxygen to carbon ratio in the biochar, which was evidence of chemical oxidation from the acid treatment. Further, TGA study showed the reduced thermal stability of acid-treated biochar over 200 °C due to the increased oxygen content. Acid treatments also influenced the graphitic structure of the biochar, as observed in the Raman spectra. The results suggest that biochar can be successfully functionalized for composite applications and provide a sustainable alternative to petroleum-based carbon additives. - Highlights: • Biochar was investigated as a candidate for renewable functionalized carbon. • Oxidative acid treatment was used to modify the carbon structure. • The chemical and morphological properties of the treated biochar were examined. • Successful chemical modification of biochar was verified through characterization. • Biochar shows potential as a sustainable carbon additive for polymer composites.

  18. Salicylic Acid Induction of Flavonoid Biosynthesis Pathways in Wheat Varies by Treatment.

    Science.gov (United States)

    Gondor, Orsolya K; Janda, Tibor; Soós, Vilmos; Pál, Magda; Majláth, Imre; Adak, Malay K; Balázs, Ervin; Szalai, Gabriella

    2016-01-01

    Salicylic acid is a promising compound for the reduction of stress sensitivity in plants. Although several biochemical and physiological changes have been described in plants treated with salicylic acid, the mode of action of the various treatments has not yet been clarified. The present work reports a detailed comparative study on the effects of different modes of salicylic acid application at the physiological, metabolomic, and transcriptomic levels. Seed soaking and hydroponic treatments were found to induce various changes in the protective mechanisms of wheat plants. The possible involvement of the flavonoid metabolism in salicylic acid-related stress signaling was also demonstrated. Different salicylic acid treatments were shown to induce different physiological and biochemical processes, with varying responses in the leaves and roots. Hydroponic treatment enhanced the level of oxidative stress, the expression of genes involved in the flavonoid metabolism and the amount of non-enzymatic antioxidant compounds, namely ortho-hydroxycinnamic acid and the flavonol quercetin in the leaves, while it decreased the ortho-hydroxycinnamic acid and flavonol contents and enhanced ascorbate peroxidase activity in the roots. In contrast, seed soaking only elevated the gene expression level of phenylalanine ammonia lyase in the roots and caused a slight increase in the amount of flavonols. These results draw attention to the fact that the effects of exogenous salicylic acid application cannot be generalized in different experimental systems and that the flavonoid metabolism may be an important part of the action mechanisms induced by salicylic acid.

  19. Different salicylic acid treatments differentially act through the induction of the flavonoid biosynthetic pathway in wheat

    Directory of Open Access Journals (Sweden)

    Orsolya Kinga Gondor

    2016-09-01

    Full Text Available Salicylic acid is a promising compound for the reduction of stress sensitivity in plants. Although several biochemical and physiological changes have been described in plants treated with salicylic acid, the mode of action of the various treatments has not yet been clarified. The present work reports a detailed comparative study on the effects of different modes of salicylic acid application at the physiological, metabolomic and transcriptomic levels. Seed soaking and hydroponic treatments were found to induce various changes in the protective mechanisms of wheat plants. The possible involvement of the flavonoid metabolism in salicylic acid-related stress signaling was also demonstrated. Different salicylic acid treatments were shown to induce different physiological and biochemical processes, with varying responses in the leaves and roots. Hydroponic treatment enhanced the level of oxidative stress, the expression of genes involved in the flavonoid metabolism and the amount of non-enzymatic antioxidant compounds, namely ortho-hydroxycinnamic acid and the flavonol quercetin in the leaves, while it decreased the ortho-hydroxycinnamic acid and flavonol contents and enhanced ascorbate peroxidase activity in the roots. In contrast, seed soaking only elevated the gene expression level of phenylalanine ammonia lyase in the roots and caused a slight increase in the amount of flavonols. These results draw attention to the fact that the effects of exogenous salicylic acid application cannot be generalized in different experimental systems and that the flavonoid metabolism may be an important part of the action mechanisms induced by salicylic acid.

  20. EXPERIENCE OF TREATMENT WITH IBANDRONIC ACID IN PATIENTS WITH SEVERE RHEUMATOLOGICAL DISEASES AND SYSTEMIC OSTEOPOROSIS

    Directory of Open Access Journals (Sweden)

    A.O. Lisitsyn

    2010-01-01

    Full Text Available This article presents the results of a study of effectiveness and safety of ibandronic acid in 21 children with rheumatologic diseases and severe systemic osteoporosis. The treatment with ibandronic acid during 48 weeks provided statistically significant increase of mineral density of bones, decrease of pain intensity, lessening of serum concentration of bone resorption marker — C-terminal telopeptide. The development of repeated compressive fractures of vertebrae and bones of peripheral skeleton at the time of treatment with this medication was not detected. Key words: children, rheumatological diseases, osteoporosis, treatment, bifosfonates, ibandronic acid.(Voprosy sovremennoi pediatrii — Current Pediatrics. 2010;9(1:116-121

  1. O2 electrocatalysis in acid media on iron naphthalocyanine impregnations. Effect of nitric acid treatment on different carbon black supports

    NARCIS (Netherlands)

    Coowar, F.; Contamin, O.; Savy, M.; Scarbeck, G.; van den Ham, D.; Riga, J.; Verbist, J.J.

    1991-01-01

    O2 electrocatalysis on (2,3)FeNPc impregnations on different carbon blacks was investigated in H2SO4 medium. The effect of nitric acid treatment on the carbon black support is to enhance both the activity and stability of the catalyst. Moreover, as seen by XPS, the dissolution of iron is impeded by

  2. Long-term treatment of menorrhagia with mefenamic acid.

    Science.gov (United States)

    Fraser, I S; McCarron, G; Markham, R; Robinson, M; Smyth, E

    1983-01-01

    Thirty-six women with menorrhagia were treated with mefenamic acid during all menstrual periods for more than 1 year. These women had experienced objective and subjective benefit--menstrual blood loss was reduced and other menstrual symptoms improved during a preliminary 4-cycle double-blind placebo-controlled trial with mefenamic acid (placebo cycles: 65.6 +/- 5.3 ml; mefenamic acid cycles: 45.3 +/- 5.1 ml, mean +/- SEM). This reduction in menstrual blood loss was maintained at 6 to 9 months (49.2 +/- 9.9 ml) and at 12 to 15 months (42.8 +/- 4.8 ml) after the trial. These reductions were significant at the 6- to 9-month (paired t test = 2.18; P less than .05) and the 12- to 15-month interval (paired t test =- 4.40; P less than .001). Significant sustained reductions in blood loss were seen in the women with menorrhagia due to ovulatory dysfunctional bleeding and in those who had undergone tubal sterilization. Significant reductions were also seen in dysmenorrhea, headache, nausea, diarrhea, depression, number of sanitary towels used, and number of mefenamic acid capsules taken. A significant increase in serum ferritin was found between admission and completion of the follow-up trial in 11 women (P less than .01).

  3. Withdrawal of valproic acid treatment during pregnancy and seizure outcome

    DEFF Research Database (Denmark)

    Tomson, Torbjörn; Battino, Dina; Bonizzoni, Erminio

    2016-01-01

    Based on data from the EURAP observational International registry of antiepileptic drugs (AEDs) and pregnancy, we assessed changes in seizure control and subsequent AED changes in women who underwent attempts to withdraw valproic acid (VPA) during the first trimester of pregnancy. Applying Bayesi...

  4. Treatment of lethal acetylsalicylic acid poisoning without hemodialysis.

    Science.gov (United States)

    Ueno, Masahito; Oda, Jun; Soeda, Hiroshi; Uesugi, Hirotaka; Ueno, Keiko; Fujise, Yo; Yukioka, Tetsuo

    2015-04-01

    A woman aged in her 20s ingested approximately 99 g acetylsalicylic acid, and was transported to our hospital 2 h later. She was lucid, but complained of hearing loss and tinnitus. We performed gastric lavage and gave her activated charcoal several times. We attempted to maintain the urinary pH at 7.5 and output above 100 mL/h while preparing for urgent hemodialysis. It was revealed after discharge that the blood concentration of acetylsalicylic acid was 103.8 mg/dL on admission (lethal dose level) and had decreased to 35.4 mg/dL by the next morning. The half-life was 8.5 h. Hemodialysis is strongly recommended for patients who take a lethal dose of acetylsalicylic acid. However, by carefully evaluating the vital signs and urinary output and pH, while preparing for emergency hemodialysis, we consider that it is possible to treat acetylsalicylic acid poisoning by alkaline diuresis and critical supportive care.

  5. Ursolic Acid Florotriazole Treatment Causes Inhibition of Squamous ...

    African Journals Online (AJOL)

    Purpose: To investigate the effect of ursolic acid florotriazole (UFT), on SCC-15 oral squamous cancer cells. Methods: Confocal laser microscope with a 490 nm argon laser was used to record the fluorescence of the cells and capture the images. Flow cytometry and Cell Quest program were used to analyze the DNA content ...

  6. Azelaic acid in the treatment of papulopustular rosacea: a systematic review of randomized controlled trials.

    Science.gov (United States)

    Liu, Rosemarie H; Smith, Molly K; Basta, Sameh A; Farmer, Evan R

    2006-08-01

    To evaluate the clinical efficacy of topical 20% azelaic acid cream and 15% azelaic acid gel compared with their respective vehicles and metronidazole gel in the treatment of papulopustular rosacea. Electronic searches of MEDLINE, EMBASE, BIOSIS, and SciSearch through July or August 2004 and the Cochrane Central Register of Controlled Trials through 2004 (issue 3). We performed hand searches of reference lists, conference proceedings, and clinical trial databases. Experts in rosacea and azelaic acid were contacted. Randomized controlled trials involving topical azelaic acid (cream or gel) for the treatment of rosacea compared with placebo or other topical treatments. Two authors independently examined the studies identified by the searches. Ten studies were identified, of which 5 were included (873 patients). Two authors independently extracted data from the included studies, then jointly assessed methodological quality using a quality assessment scale. Because standard deviation data were not available for 4 of the 5 studies, a meta-analysis could not be conducted. Four of the 5 studies demonstrated significant decreases in mean inflammatory lesion count and erythema severity after treatment with azelaic acid compared with vehicle. None of the studies showed any significant decrease in telangiectasia severity. Azelaic acid in 20% cream and 15% gel formulations appears to be effective in the treatment of papulopustular rosacea, particularly in regard to decreases in mean inflammatory lesion count and erythema severity. Compared with metronidazole, azelaic acid appears to be an equally effective, if not better, treatment option.

  7. Influence of concentration in phosphoric acid treatment of titanium oxide and their powder properties

    Directory of Open Access Journals (Sweden)

    Hiroaki Onoda

    2015-03-01

    Full Text Available Titanium oxide that has the photocatalytic activity is used as a white pigment for cosmetics. A certain degree of sebum on the skin is decomposed by the ultraviolet radiation in sunlight. In this work, titanium oxide was shaken with various concentrations of phosphoric acid to synthesize a novel white pigment for cosmetics. Their chemical composition, powder properties, photocatalytic activity, color phase, and smoothness were studied. The obtained materials indicated XRD peaks of titanium oxide; however, these peak intensities became weak by phosphoric acid treatment. The photocatalytic activity of the obtained powders became weak by phosphoric acid treatment to protect the sebum on the skin. The high concentration of phosphoric acid was suitable to obtain a novel white pigment in the phosphoric acid treatment of titanium oxide.

  8. Acid digestion and pressurization control in combustible radwaste treatment

    International Nuclear Information System (INIS)

    Allen, C.R.; Cowan, R.G.; Grelecki, C.J.

    1978-01-01

    Acid digestion has been developed to reduce the volume of combustible nuclear waste materials, while converting them to an inert, noncombustible residue. A 100 kg/day test unit has recently been constructed to process radioactively contaminated combustible wastes. The unit, called the Radioactive Acid Digestion Test Unit (RADTU) was completed in September, 1977, and is currently undergoing nonradioactive shakedown tests. Radioactive operation is expected in May, 1978. Because of uncertainties in waste composition and reactivity, the system was required to contain pressurizations. This led to the development of a simple and inexpensive system, which is capable of attenuating a shock wave from a full scale vapor detonation. The system has potential application in a wide spectrum of chemical reactors, since the fabrication materials are resistant to a very wide range of corrosive chemical attack

  9. PERIODS OF VERTEBRAL COLUMN SENSITIVITY TO BORIC ACID TREATMENT IN CD-1 MICE IN UTERO

    Science.gov (United States)

    Periods of vertebral column sensitivity to boric acid treatment in CD-1 mice in utero.Cherrington JW, Chernoff N.Department of Toxicology, North Carolina State University, Raleigh, NC 27695, USA. jana_cherrington@hotmail.comBoric acid (BA) has many uses as...

  10. Effect of glow discharge treatment of poly(acrylic acid) preadsorbed onto poly(ethylene)

    NARCIS (Netherlands)

    Terlingen, J.G.A.; Terlingen, Johannes G.A.; Hoffman, Allan S.; Feijen, Jan

    1993-01-01

    In order to introduce carboxylic acid groups at the surface of poly(ethylene) (PE) films, an attempt was made to covalently link a preadsorbed layer of poly(acrylic acid) (PAAc) on a PE film by an argon or tetrafluoromethane (CF4) plasma treatment. Surface analysis was performed by XPS (X-ray

  11. Ursodeoxycholic acid for treatment of primary sclerosing cholangitis: a placebo-controlled trial

    NARCIS (Netherlands)

    Beuers, U.; Spengler, U.; Kruis, W.; AYDEMIR, U.; WIEBECKE, B.; HELDWEIN, W.; WEINZIERL, M.; Pape, G. R.; Sauerbruch, T.; Paumgartner, G.

    1992-01-01

    The efficacy and safety of ursodeoxycholic acid for the treatment of primary sclerosing cholangitis were evaluated in a prospective, randomized, double-blind, placebo-controlled trial. Fourteen patients with primary sclerosing cholangitis documented by cholestatic serum enzyme pattern, liver

  12. Retinoic acid for treatment of systemic sclerosis and morphea: A literature review.

    Science.gov (United States)

    Thomas, Renee M; Worswick, Scott; Aleshin, Maria

    2017-03-01

    Systemic sclerosis and morphea are connective tissue diseases characterized by tightening, thickening, and hardening of the skin, leading to significant morbidity. Unfortunately, current treatment options have limited efficacy for many patients. Cutaneous manifestations of these diseases arise from excess collagen deposition and fibrosis in the skin, through pathogenic mechanisms which have yet to be extensively detailed at the causal immune and cellular levels. Research elucidating the mechanism of action of retinoic acid on collagen production in the skin and case series highlighting the success of retinoic acid on the skin manifestations of systemic sclerosis and on morphea demonstrate its promise as a treatment. Herein they will briefly review the treatment options for both systemic sclerosis and morphea, and will discuss the potential of retinoic acid as a therapy and the supporting evidence from the literature, highlighting the previously published basic science and clinical studies investigating the role of retinoic acid in the treatment of sclerotic skin diseases. © 2016 Wiley Periodicals, Inc.

  13. [Injuries caused by acids and bases - emergency treatment].

    Science.gov (United States)

    Reifferscheid, Florian; Stuhr, Markus; Kaiser, Guido; Freudenberg, Matthias; Kerner, Thoralf

    2014-06-01

    Emergency medical care for injuries caused by acids and bases is challenging for rescue services. They have to deal with operational safety, detection of the toxic agent, emergency medical care of the patient and handling of the rescue mission. Because of the rareness of such situations experience and routine are largely missing. This article highlights some basic points for the therapy and provides support for such rescue missions. © Georg Thieme Verlag Stuttgart · New York.

  14. Furanyl Fatty Acid Inhibition of FABP5 as a Mechanism for Treatment and Prevention of Cancer

    Science.gov (United States)

    2017-10-01

    AWARD NUMBER: W81XWH-16-1-0699 TITLE: Furanyl Fatty Acid Inhibition of FABP5 as a Mechanism for Treatment and Prevention of Cancer PRINCIPAL...pharmacologic inhibition will prevent the oncogenic effects of FABP5 overexpression in highly relevant breast cancer models that display a high ratio of...Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. Z39.18 Furanyl Fatty Acid Inhibition of FABP5 as a Mechanism for Treatment and Prevention of

  15. Hydrolysis of Miscanthus for bioethanol production using dilute acid presoaking combined with wet explosion pre-treatment and enzymatic treatment

    DEFF Research Database (Denmark)

    Sørensen, Annette; Teller, Philip Johan; Hilstrøm, Troels

    2008-01-01

    xylose prior to wet explosion. The acid presoaking extracted 63.2% xylose and 5.2% glucose. Direct enzymatic hydrolysis of the presoaked biomass was found to give only low sugar yields of 24-26% glucose. Wet explosion is a pre-treatment method that combines wet-oxidation and steam explosion. The effect...... of wet explosion on non-presoaked and presoaked Miscanthus was investigated using both atmospheric air and hydrogen peroxide as the oxidizing agent. All wet explosion pre-treatments showed to have a disrupting effect on the lignocellulosic biomass, making the sugars accessible for enzymatic hydrolysis......Miscanthus is a high yielding bioenergy crop. In this study we used acid presoaking, wet explosion, and enzymatic hydrolysis to evaluate the combination of the different pre-treatment methods for bioethanol production with Miscanthus. Acid presoaking is primarily carried out in order to remove...

  16. Tracking acidic pharmaceuticals, caffeine, and triclosan through the wastewater treatment process.

    Science.gov (United States)

    Thomas, Paul M; Foster, Gregory D

    2005-01-01

    Pharmaceuticals are a class of emerging contaminants whose fate in the wastewater treatment process has received increasing attention in past years. Acidic pharmaceuticals (ibuprofen, naproxen, mefenamic acid, ketoprofen, and diclofenac), caffeine, and the antibacterial triclosan were quantified at four different steps of wastewater treatment from three urban wastewater treatment plants. The compounds were extracted from wastewater samples on Waters Oasis hydrophilic-lipophilic balance solid-phase extraction columns, silylated, and analyzed by gas chromatography-mass spectrometry. For the chemicals studied, it was found that the majority of the influent load was removed during secondary treatment (51-99%), yielding expected surface water concentrations of 13 to 56 ng/L.

  17. Mobile Clinical Decision Support System for Acid-base Balance Diagnosis and Treatment Recommendation.

    Science.gov (United States)

    Mandzuka, Mensur; Begic, Edin; Boskovic, Dusanka; Begic, Zijo; Masic, Izet

    2017-06-01

    This paper presents mobile application implementing a decision support system for acid-base disorder diagnosis and treatment recommendation. The application was developed using the official integrated development environment for the Android platform (to maximize availability and minimize investments in specialized hardware) called Android Studio. The application identifies disorder, based on the blood gas analysis, evaluates whether the disorder has been compensated, and based on additional input related to electrolyte imbalance, provides recommendations for treatment. The application is a tool in the hands of the user, which provides assistance during acid-base disorders treatment. The application will assist the physician in clinical practice and is focused on the treatment in intensive care.

  18. Production of γ-Amino Butyric Acid in Tea Leaves wit Treatment of Lactic Acid Bacteria

    Science.gov (United States)

    Watanabe, Yuko; Hayakawa, Kiyoshi; Ueno, Hiroshi

    Lactic acid bacteria was searched for producing termented tea that contained a lot of γ-amino butyric acid(GABA). Also examined were the growth condition, GABA production and changes in catechin contents in the tea leaves. Lactobacillus brevis L12 was found to be suitable for the production of fermented tea since it gave as much GABA as gabaron tea when tea leaves being suspended with water at 10% and incubated for 4 days at 25°C. The amount of GABA produced was more than calculated based upon the content of glutamic acid in tea leaves. It is probable to assume that glutamate derived from glutamine and theanine is converted into GABA.

  19. Treatment of Alzheimer's Disease with Anti-Homocysteic acid Antibody

    OpenAIRE

    Tohru Hasegawa; Nobuyuki Mikoda; Masashi Kitazawa; Frank M. LaFerla

    2008-01-01

    Homocysteic acid (HA) may play an important role in Alzhiemer disease (AD) as we previously reported that HA induced accumulation of intraneuronal A[beta]42. In this study, we first analyzed HA levels in a mouse model of AD. 4-month old pre-pathologic 3xTg-AD mice exhibited higher levels of HA in the hippocampus as compared to age-matched nontransgenic, suggesting that HA accumulation may precede both A[beta] and tau pathologies. To further determine the pathogenic role of HA in AD, we treate...

  20. Effect of Ultrasonic Treatment Combined with Peracetic Acid Treatment Reduces Decay and Maintains Quality in Loquat Fruit

    Directory of Open Access Journals (Sweden)

    Chen Ling

    2018-01-01

    Full Text Available The effects of ultrasonic treatment (UT, 400 watts for 6 min combined with peracetic acid (PA, 0.4% (W/W treatment on fruit decay, browning, and quality and physiological changes in loquat fruit stored at 20°C were investigated. The results showed that treatment with UT or PA alone significantly reduced both decay and browning index in loquat fruit compared with the control. The combined treatment was more effective in decreasing decay and browning index and maintaining higher quality parameters than UT or PA treatment alone. Loquat fruits treated with the combined treatment maintained higher activities of polyphenol oxidase (PPO and peroxidase (POD than those treated with other treatments. In addition, UT combined with PA treatment significantly reduced the increase of firmness and increased fruit extractable juice, total soluble solid (TSS, and ascorbic acid content in loquat fruit. Moreover, the contents of total phenolics and total flavonoids were enhanced by the combination of UT and PA treatment. The combination of UT and PA treatment could be a useful method to reduce decay and browning in loquat fruit stored at room temperature, which has potential for application in the loquat industry.

  1. Comparative study of 15% TCA peel versus 35% glycolic acid peel for the treatment of melasma.

    Science.gov (United States)

    Puri, Neerja

    2012-05-01

    Chemical peels are the mainstay of a cosmetic practitioner's armamentarium because they can be used to treat some skin disorders and can provide aesthetic benefit. To compare 15% TCA peel and 35% glycolic acid peel for the treatment of melasma. We selected 30 participants of melasma aged between 20 and 50 years from the dermatology outpatient department and treated equal numbers with 15% TCA and 35% glycolic acid. Subjective response as graded by the patient showed good or very good response in 70% participants in the glycolic acid group and 64% in the TCA group. There was statistically insignificant difference in the efficacy between the two groups for the treatment of melasma.

  2. Treatment of type 2 diabetes by free Fatty Acid receptor agonists

    DEFF Research Database (Denmark)

    Watterson, Kenneth R; Hudson, Brian D; Ulven, Trond

    2014-01-01

    Dietary free fatty acids (FFAs), such as ω-3 fatty acids, regulate metabolic and anti-inflammatory processes, with many of these effects attributed to FFAs interacting with a family of G protein-coupled receptors. Selective synthetic ligands for free fatty acid receptors (FFA1-4) have consequently......-inflammatory effects of short chain fatty acids (SCFAs) are linked with FFA2 and FFA3 activation. In this review, we therefore show that FFA receptor agonism is a potential clinical target for T2D treatment and discuss ongoing drug development programs within industry and academia aimed at improving the safety...

  3. Oxidative acid treatment and characterization of new biocarbon from sustainable Miscanthus biomass.

    Science.gov (United States)

    Anstey, Andrew; Vivekanandhan, Singaravelu; Rodriguez-Uribe, Arturo; Misra, Manjusri; Mohanty, Amar Kumar

    2016-04-15

    Oxidative acid treatments of biochar produced from Miscanthus were performed in this study using nitric acid, sulfuric acid, and a mixture of both. The structural and morphological changes of the acid-treated biochar were investigated using Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), Raman spectroscopy, organic elemental analysis and energy-dispersive X-ray spectroscopy (EDS). Improved surface functionality of the treated biochars was observed in their respective FT-IR spectra through the presence of nitro and carboxylic acid functional groups. SEM-EDS and elemental analysis revealed a large increase in the oxygen to carbon ratio in the biochar, which was evidence of chemical oxidation from the acid treatment. Further, TGA study showed the reduced thermal stability of acid-treated biochar over 200°C due to the increased oxygen content. Acid treatments also influenced the graphitic structure of the biochar, as observed in the Raman spectra. The results suggest that biochar can be successfully functionalized for composite applications and provide a sustainable alternative to petroleum-based carbon additives. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Treatment of endometriosis with local acetylsalicylic acid injection: experimental study in rabbits.

    Science.gov (United States)

    Siqueira, Juliana Menezes; Barreto, Adriana Beatriz; Saad-Hossne, Rogério

    2011-01-01

    The objective of the present study was to estimate the effects of introduction of acetylsalicylic acid solution into peritoneal implants in autologous endometrium as a method for treating endometriosis. Forty adult female rabbits were subdivided into 4 groups of 10 rabbits each, and endometriosis was induced via autotransplantation of endometrial fragments into the peritoneal cavity. At 30 days after induction of endometriosis, all animals were randomly assigned to 1 of 2 protocols. In protocol 1, animals were evaluated at 24 hours after treatment; group 1 (control) received physiologic solution, and group 2 received acetylsalicylic acid. In protocol 2, animals were evaluated at 10 days after treatment, group 3 (control) and group 4 received acetylsalicylic acid. After measuring the lesion, the endometriotic focus was removed and prepared for mounting on slides for histologic analysis. Imaging software was used for analysis of the total remaining area of endometrial tissue. The affected area in acetylsalicylic acid-treated animals was smaller than that in control animals at 24 hours and 10 days after treatment; a significant difference was found between control and treated groups (p acetylsalicylic acid groups (p = .30), and no differences between times (p = .75). Acetylsalicylic acid solution led to less growth (or higher involution) of endometrial implants. Acetylsalicylic acid injected directly into endometriotic foci was effective in their destruction. This presents new perspectives for treatment of endometriosis and for clinical applications based on further clinical studies. Copyright © 2011 AAGL. Published by Elsevier Inc. All rights reserved.

  5. Efficacy of 5-Aminolevulinic Acid Photodynamic Therapy in treatment of nasal inverted papilloma.

    Science.gov (United States)

    Zhang, Yunjie; Yang, Yuguang; Zou, Xianbiao

    2013-12-01

    Evaluate the efficacy of 5-Aminolevulinic Acid Photodynamic Therapy (PDT) in medical treatment of nasal inverted papilloma (NIP). Three patients with nasal inverted papilloma were treated with 5-Aminolevulinic Acid Photodynamic Therapy at our department from April to September 2012. The efficacy and adverse effects of 5-Aminolevulinic Acid Photodynamic Therapy were evaluated during 6-8 months of follow-up medical examination. After treated with 5-Aminolevulinic Acid Photodynamic Therapy, the nasal inverted papillomas were removed. No recurrence was found during the 6-8 months of follow-up medical examination. The major adverse effects were mild erosion, pain, and exudation. 5-Aminolevulinic Acid Photodynamic Therapy appears to be an effective treatment of nasal inverted papilloma. It can clear the papilloma lesions and is well tolerated by the patients. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. (2-vinylpyridine) by treatment with crotonic acid and vinyl acetic acid

    Indian Academy of Sciences (India)

    salts or acids.1 Solid state polymer electrolytes are gain- ing importance as ionics in solid state electrochemistry dur- ing last three decades. These are used in electrochemical devices such as high energy density batteries,2,3 measur- ing systems and display devices. These are also used in solid oxide fuel cells, chemical ...

  7. Effect of salicylic acid treatment on cadmium toxicity and leaf lipid composition in sunflower

    Directory of Open Access Journals (Sweden)

    Moradkhani S.

    2012-11-01

    Full Text Available The ameliorative effect of salicylic acid (SA on cadmium (Cd toxicity in sunflower plants was studied by investigating plant growth and fatty acid composition. Sunflower plants in two leaves stage were exposed to CdCl2 treatment (0, 50, 100, 150 and 200 µM and then were treated with salicylic acid (0, 250 and 500 µM as foliage spraying. One week after the last salicylic acid treatment,plants were harvested and growth parameters were measured . Oil of leaf was extracted in a Soxhlet system and fatty acid composition were measured by gas chromatography (GC. Statistical analyses showed excess Cd reduced growth parameters (fresh weight and length of stems and roots, fresh weight and number of leavesand SA increased them compared with the control. Maximum reduction in these parameters was at 200 µmol Cd and 0µmol of SA. Cd caused a shift in fatty acids composition, resulting in a lower degree of their unsaturation and an increase in saturated fatty acids in sunflower leaves,whereas SA improved them. SA, particularly increased the percentage of linolenic acid and lowered that of palmitic acid by the same proportion. These results sugg membrane integrity due to lipids est that SA could be used as a potential growth regulator and a stabilizer ofprotection of cadmium-induced oxidative stress to improve plant resistance to Cd stress

  8. Review of Omega-3 Fatty Acids for the Treatment of Attention Deficit/Hyperactivity Disorder

    Directory of Open Access Journals (Sweden)

    Jamie N. Brown

    2009-01-01

    Full Text Available Objective To review the efficacy of omega-3 fatty acids in the treatment of attention deficit/hyperactivity disorder (ADHD. Data Souces Literature was accessed via MEDLINE (1950–February 2009 and International Pharmaceutical Abstracts (1960–2009 using the medical subject heading terms omega-3 fatty acids and attention deficit disorder with hyperactivity. Additional references were found by searching bibliographic references of resulting citations. Study Selection and Data Extraction All English-language, placebo controlled publications identified were analyzed for significance. Studies relevant to the objective were used, including eight studies evaluating the use of omega-3 fatty acid in the treatment of children with symptoms of ADHD. Data Synthesis Omega-3 fatty acid supplementation has been found to have variable efficacy in the treatment of patients with ADHD. Of the eight studies evaluated, three demonstrated no significant improvements in any evaluation criteria, with five studies reporting positive effects in at least one outcome measure. All positive efficacy studies included concomitant supplementation with omega-6 fatty acids. No clinically significant adverse effects were identified in the reviewed studies. Conclusions Based on the available data, current fatty acid supplementation techniques do not appear to be a consistant method of controlling ADHD symptoms. Without better evidence to determine the true value of fatty acids in the treatment of ADHD, omega-3 fatty acid use should be isolated to adjuvant supplementation or used in patients unable or unwilling to take stimulant medications. If recommended, there does not appear to be clinically significant adverse events associated with omega-3 fatty acid supplementation and this would be a safe treatment modality.

  9. Treatment of focal epithelial hyperplasia with trichloroacetic acid

    Directory of Open Access Journals (Sweden)

    J Harris Ricardo

    2012-12-01

    Full Text Available Focal epithelial hyperplasia is a benign disease which has a chronic course that manifests as characteristic multiple small papules or nodules. They are predominantly found in the oral mucosa, gingiva and tongue. The surface of the lesions is smooth and it varies in size. It is an asymptomatic disease caused by human papillomavirus, affecting mainly children and adolescents. In this report, we describe four cases referred to the Stomatology and Oral Surgery Department of the Faculty of Dentistry, Cartagena University with a diagnosis of focal epithelial hyperplasia. Clinical features and histopathological characteristics of the patients were recorded. We also describe the properties and advantages of trichloroacetic acid as a therapeutic method.

  10. Ursodeoxycholic Acid for the Treatment of Cholesterol Gallstones

    International Nuclear Information System (INIS)

    Zaater, M.K.

    2011-01-01

    Cholesterol is the principal constituent of more than three quarters of gallstones. Pure cholesterol crystals are quite soft, and protein contributes importantly to the strength of cholesterol stones. The risk of gallstones does not correlate with total serum cholesterol levels, but it does correlate with decreased high-density lipoprotein cholesterol and increased triglyceride levels. At least 10 percent of adults have gallstones where female: male ratio of about 2:1 in the younger age groups with increasing prevalence with age. Nine patients with gallstones (6 females and 3 males) were included in the study. Patients were treated with ursodeoxycholic acids tablets in two oral doses, one after breakfast, and the other after dinner for 9 months. Ultrasound examination was repeated every 3 months. Re-examination by abdominal ultrasonography revealed that gallstone 1 cm or less in diameter disappeared within 6 months, and the largest stone 3.06 cm in diameter disappeared within 9 months.

  11. Nucleic acid toolkit: Potential diagnosis and treatment of major infectious diseases endemic in developing countries

    CSIR Research Space (South Africa)

    Millroy, L

    2011-09-01

    Full Text Available provides insights into their current diagnostics and treatments and the future prospects. In particular, the book highlights the use of nucleic acid therapies and focuses on the use of aptamers as potential treatment and diagnostic tools for these diseases...

  12. Comparison of trichostatin A and valproic acid treatment regimens in a mouse model of kidney fibrosis

    Energy Technology Data Exchange (ETDEWEB)

    Van Beneden, Katrien, E-mail: kvbenede@vub.ac.be [Department of Human Anatomy, Liver Cell Biology Lab, Vrije Universiteit Brussel, Brussels (Belgium); Geers, Caroline [Department of Pathology, Universitair Ziekenhuis Brussel, Brussels (Belgium); Pauwels, Marina [Department of Human Anatomy, Liver Cell Biology Lab, Vrije Universiteit Brussel, Brussels (Belgium); Mannaerts, Inge [Department of Cell Biology, Liver Cell Biology Lab, Vrije Universiteit Brussel, Brussels (Belgium); Wissing, Karl M. [Department of Nephrology, Universitair Ziekenhuis Brussel, Brussels (Belgium); Van den Branden, Christiane [Department of Human Anatomy, Liver Cell Biology Lab, Vrije Universiteit Brussel, Brussels (Belgium); Grunsven, Leo A. van, E-mail: lvgrunsv@vub.ac.be [Department of Cell Biology, Liver Cell Biology Lab, Vrije Universiteit Brussel, Brussels (Belgium)

    2013-09-01

    Histone deacetylase (HDAC) inhibitors are promising new compounds for the therapy of fibrotic diseases. In this study we compared the effect of two HDAC inhibitors, trichostatin A and valproic acid, in an experimental model of kidney fibrosis. In mice, doxorubicin (adriamycin) can cause nephropathy characterized by chronic proteinuria, glomerular damage and interstitial inflammation and fibrosis, as seen in human focal segmental glomerulosclerosis. Two treatment regimens were applied, treatment was either started prior to the doxorubicin insult or delayed until a significant degree of proteinuria and fibrosis was present. Pre-treatment of trichostatin A significantly hampered glomerulosclerosis and tubulointerstitial fibrosis, as did the pre-treatment with valproic acid. In contrast, the development of proteinuria was only completely inhibited in the pre-treated valproic acid group, and not in the pre-treated trichostatin A animals. In the postponed treatment with valproic acid, a complete resolution of established doxorubicin-induced proteinuria was achieved within three days, whereas trichostatin A could not correct proteinuria in such a treatment regimen. However, both postponed regimens have comparable efficacy in maintaining the kidney fibrosis to the level reached at the start of the treatments. Moreover, not only the process of fibrosis, but also renal inflammation was attenuated by both HDAC inhibitors. Our data confirm a role for HDACs in renal fibrogenesis and point towards a therapeutic potential for HDAC inhibitors. The effect on renal disease progression and manifestation can however be different for individual HDAC inhibitors. - Highlights: • Valproic acid is a potent antiproteinuric drug, whereas trichostatin A is not. • Trichostatin A and valproic acid reduce kidney fibrosis in doxorubicin nephropathy. • Both valproic acid and trichostatin A attenuate renal inflammation.

  13. Ascorbic acid for the treatment of Charcot-Marie-Tooth disease.

    Science.gov (United States)

    Gess, Burkhard; Baets, Jonathan; De Jonghe, Peter; Reilly, Mary M; Pareyson, Davide; Young, Peter

    2015-12-11

    Charcot-Marie-Tooth disease (CMT) comprises a large group of different forms of hereditary motor and sensory neuropathy. The molecular basis of several CMT subtypes has been clarified during the last 20 years. Since slowly progressive muscle weakness and sensory disturbances are the main features of these syndromes, treatments aim to improve motor impairment and sensory disturbances to improve abilities. Pharmacological treatment trials in CMT are rare. This review was derived from a Cochrane review, Treatment for Charcot Marie Tooth disease, which will be updated via this review and a forthcoming title, Treatments other than ascorbic acid for Charcot-Marie-Tooth disease. To assess the effects of ascorbic acid (vitamin C) treatment for CMT. On 21 September 2015, we searched the Cochrane Neuromuscular Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and LILACS for randomised controlled trials (RCTs) of treatment for CMT. We also checked clinical trials registries for ongoing studies. We included RCTs and quasi-RCTs of any ascorbic acid treatment for people with CMT. Where a study aimed to evaluate the treatment of general neuromuscular symptoms of people with peripheral neuropathy including CMT, we included the study if we were able to identify the effect of treatment in the CMT group. We did not include observational studies or case reports of ascorbic acid treatment in people with CMT. Two review authors (BG and JB) independently extracted the data and assessed study quality. Six RCTs compared the effect of oral ascorbic acid (1 to 4 grams) and placebo treatment in CMT1A. In five trials involving adults with CMT1A, a total of 622 participants received ascorbic acid or placebo. Trials were largely at low risk of bias. There is high-quality evidence that ascorbic acid does not improve the course of CMT1A in adults as measured by the CMT neuropathy score (0 to 36 scale) at 12 months (mean difference (MD) -0.37; 95

  14. Combined Treatment with Hyaluronic Acid and Mesalamine Protects Rats from Inflammatory Bowel Disease Induced by Intracolonic Administration of Trinitrobenzenesulfonic Acid

    Directory of Open Access Journals (Sweden)

    Chih-Tung Chiu

    2017-05-01

    Full Text Available Drugs such as mesalamine (5-ASA are currently recommended for the treatment of inflammatory bowel disease (IBD. To reduce the frequency of their administration and improve their therapeutic effect, this study investigated the adhesion efficacy, wound healing promotion, and decrease in inflammation in ulcers in the colonic tissue of rats with colitis after combined treatment with hyaluronic acid (HA and 5-ASA (IBD98-M. HA-fluoresceinamine (FL conjugates successfully adhered to the mucosal layer and were conjugated in the vascular tissue. In addition, macroscopic and microscopic observations indicated that colonic injuries reduced significantly after treatment with IBD98-M. Compared with PBS and 5-ASA treatment alone, treatment with IBD98-M more effectively reduced bowel inflammation and promoted colonic mucosal healing in TNBS-induced colitis. IBD98-M treatment also reduced myeloperoxidase activity and the expression levels of cyclooxygenase 2 and tumor necrosis factor-αin the colitis tissue. In conclusion, IBD98-M treatment strongly promoted wound healing in colonic injuries and significantly inhibited MPO activity in the inflamed colon tissue of rats. Combined treatment with HA and 5-ASA can accelerate wound healing and reduce inflammatory reaction in rat colitis.

  15. Efficacy of topical azelaic acid gel in the treatment of mild-moderate acne vulgaris

    Directory of Open Access Journals (Sweden)

    Iraji Fariba

    2007-01-01

    Full Text Available Background: Twenty percent azelaic acid gel is recommended as a topical treatment for acne due to its favorable profile. Aim: Our objective in this study was to evaluate the efficacy of 20% azelaic acid gel in the treatment of mild to moderate acne vulgaris. Methods: This was a double blind, randomized clinical trial. Sixty patients with mild to moderate acne vulgaris were selected randomly to receive either azelaic acid gel or the vehicle gel alone. Patients were followed up every 15 days for a period of 45 days. The number of lesions and the acne severity index (ASI were recorded and compared using Student′s t-test. Results: Total lesion count was reduced by 60.6% and 19.9% by azelaic acid gel and the placebo respectively (P =0.002. ASI was reduced by 65.2% and 21.3% by azelaic acid gel and the placebo respectively (P =0.001, i.e., azelaic acid gel was 3.06 times more effective than the placebo in reducing ASI. Conclusion: Azelaic acid gel can be used as an effective treatment in mild to moderate acne vulgaris.

  16. Sialic acid changes in Dalton's lymphoma-bearing mice after cyclophosphamide and cisplatin treatment

    Directory of Open Access Journals (Sweden)

    Nicol B.M.

    2002-01-01

    Full Text Available Sialic acid changes in Dalton's lymphoma cells and other tissues of 10-12-week-old Swiss albino mice were investigated in relation to tumour growth in vivo and following cyclophosphamide (ip, 200 mg/kg body weight or cisplatin (ip, 8 mg/kg body weight treatment. Three to four animals of both sexes were used in each experimental group. The sialic acid level of tumour cells (0.88 µmol/g increased with tumour progression (1.44-1.59 µmol/g; P<=0.05 in mice. Sialic acid concentration in other tissues (liver, kidney, testes and brain also increased (~40, 10, 30 and 58%, respectively in the tumour-bearing hosts as compared with that in the respective tissues of normal mice. In vivo cyclophosphamide or cisplatin treatment resulted in an overall decrease of sialic acid contents in the tissues. Cyclophosphamide was more efficient in lowering tissue sialic acid than cisplatin (P<=0.01, ANOVA. It is suggested that sialic acid residues could be an important factor contributing to the manifestation of malignant properties in cancer cells in general and Dalton's lymphoma cells in particular. A significant decrease in the sialic acid content of Dalton's lymphoma cells after cisplatin or cyclophosphamide treatment may bring about specific changes in tumour cells which could be associated with tumour regression.

  17. Efficacy of topical azelaic acid gel in the treatment of mild-moderate acne vulgaris.

    Science.gov (United States)

    Iraji, Fariba; Sadeghinia, Ali; Shahmoradi, Zabiholahi; Siadat, Amir Hossein; Jooya, Abolfazl

    2007-01-01

    Twenty percent azelaic acid gel is recommended as a topical treatment for acne due to its favorable profile. Our objective in this study was to evaluate the efficacy of 20% azelaic acid gel in the treatment of mild to moderate acne vulgaris. This was a double blind, randomized clinical trial. Sixty patients with mild to moderate acne vulgaris were selected randomly to receive either azelaic acid gel or the vehicle gel alone. Patients were followed up every 15 days for a period of 45 days. The number of lesions and the acne severity index (ASI) were recorded and compared using Student's t-test. Total lesion count was reduced by 60.6% and 19.9% by azelaic acid gel and the placebo respectively (P = 0.002). ASI was reduced by 65.2% and 21.3% by azelaic acid gel and the placebo respectively (P = 0.001), i.e, azelaic acid gel was 3.06 times more effective than the placebo in reducing ASI. Azelaic acid gel can be used as an effective treatment in mild to moderate acne vulgaris.

  18. Inhibition of breast cancer cell proliferation in repeated and non-repeated treatment with zoledronic acid

    Directory of Open Access Journals (Sweden)

    Ibrahim Toni

    2012-11-01

    Full Text Available Abstract Background Zoledronic acid is used to treat bone metastases and has been shown to reduce skeletal-related events and exert antitumor activity. The present in vitro study investigates the mechanism of action of Zoledronic Acid on breast cancer cell lines with different hormonal and HER2 patterns. Furthermore, we investigated the efficacy of repeated versus non-repeated treatments. Methods The study was performed on 4 breast cancer cell lines (BRC-230, SkBr3, MCF-7 and MDA-MB-231. Non-repeated treatment (single exposure of 168 hrs’ duration with zoledronic acid was compared with repeated treatment (separate exposures, each of 48 hrs’ duration, for a total of 168 hrs at different dosages. A dose–response profile was generated using sulforhodamine B assay. Apoptosis was evaluated by TUNEL assay and biomolecular characteristics were analyzed by western blot. Results Zoledronic acid produced a dose-dependent inhibition of proliferation in all cell lines. Anti-proliferative activity was enhanced with the repeated treatment, proving to be statistically significant in the triple-negative lines. In these lines repeated treatment showed a cytocidal effect, with apoptotic cell death caused by caspase 3, 8 and 9 activation and decreased RAS and pMAPK expression. Apoptosis was not observed in estrogen receptor-positive line: p21 overexpression suggested a slowing down of cell cycle. A decrease in RAS and pMAPK expression was seen in HER2-overexpressing line after treatment. Conclusions The study suggests that zoledronic acid has an antitumor activity in breast cancer cell lines. Its mechanism of action involves the decrease of RAS and RHO, as in osteoclasts. Repeated treatment enhances antitumor activity compared to non-repeated treatment. Repeated treatment has a killing effect on triple-negative lines due to apoptosis activation. Further research is warranted especially in the treatment of triple-negative breast cancer.

  19. "One-step" simplified electrochemical sensing of TATP based on its acid treatment.

    Science.gov (United States)

    Munoz, Rodrigo A A; Lu, Donglai; Cagan, Avi; Wang, Joseph

    2007-06-01

    A fast, simple and sensitive electrochemical method for sensing peroxide-based explosives based on their acid treatment is reported. The method relies on the high electrocatalytic activity of Prussian-blue (PB)-modified electrodes towards the acid-generated hydrogen peroxide in the harsh acidic medium (down to pH 0.3) used for releasing hydrogen peroxide. Such effective operation of PB electrochemical sensors in strongly acidic media eliminates the need for an additional neutralization step required in analogous peroxidase-based assays (due to acid-induced enzyme deactivation processes). Factors affecting the efficiency of the acid pre-treatment of triacetone triperoxide (TATP) have been examined and optimized to allow its sensitive measurement down to the 50 ng level within 60 s. Chronoamperometric detection of microgram amounts of solid TATP, following a one-minute acid mixing and placing a 20 microL droplet onto a disposable PB-modified screen-printed electrode is illustrated. Similar results were obtained for the peroxide explosive hexamethylene triperoxide diamine (HMTD). By greatly simplifying the analytical procedure, such an acid-operated "artificial peroxidase" electrocatalytic transducer holds great promise for designing "one-step", user-friendly, miniaturized, cost-effective devices for field screening of peroxide explosives.

  20. Modeling and optimizing the design of matrix treatments in carbonate reservoirs with self-diverting acid systems

    International Nuclear Information System (INIS)

    Bulgakova, G T; Kharisov, R Ya; Sharifullin, A R; Pestrikov, A V

    2015-01-01

    Application of a self-diverting-acid based on viscoelastic surfactant (SDVA) is a promising technology for improving the efficacy of acid treatment in oil and gas-bearing carbonate reservoirs. In this study, we present a mathematical model for assessing SDVA flow and reaction with carbonate rock using the SDVA rheological characteristics. The model calculates the technological parameters for acidizing operations and the prediction of well productivity after acid treatment, in addition to technical and economic optimization of the acidizing process by modeling different acid treatment options with varying volumes, injection rates, process fluids stages and initial economic scenarios

  1. Impact of Surface Potential on Apatite Formation in Ti Alloys Subjected to Acid and Heat Treatments.

    Science.gov (United States)

    Yamaguchi, Seiji; Hashimoto, Hideki; Nakai, Ryusuke; Takadama, Hiroaki

    2017-09-24

    Titanium metal (Ti) and its alloys are widely used in orthopedic and dental fields. We have previously shown that acid and heat treatment was effective to introduce bone bonding, osteoconduction and osteoinduction on pure Ti. In the present study, acid and heat treatment with or without initial NaOH treatment was performed on typical Ti-based alloys used in orthopedic and dental fields. Dynamic movements of alloying elements were developed, which depended on the kind of treatment and type of alloy. It was found that the simple acid and heat treatment enriched/remained the alloying elements on Ti-6Al-4V, Ti-15Mo-5Zr-3Al and Ti-15Zr-4Nb-4Ta, resulting in neutral surface charges. Thus, the treated alloys did not form apatite in a simulated body fluid (SBF) within 3 days. In contrast, when the alloys were subjected to a NaOH treatment prior to an acid and heat treatment, alloying elements were selectively removed from the alloy surfaces. As a result, the treated alloys became positively charged, and formed apatite in SBF within 3 days. Thus, the treated alloys would be useful in orthopedic and dental fields since they form apatite even in a living body and bond to bone.

  2. The effect of oleic acid as post spinning treatment on tensile strength of polyacrylonitrile fibers

    Science.gov (United States)

    Salleh, Shahrul Nizam Md; Zainon, Nurazilah Mohd; Abdullah, Mohamad Zaki

    2017-12-01

    Carbon fiber precursor was derived from Polyacrylonitrile (PAN) polymer, pitch based and cellulose rayon. Until now, the best precursor for carbon fibre is PAN polymer. This is because PAN polymer precursor have higher carbon content when subjected to heat treatment process. After spinning process, the PAN fibre will be soaked in a chemical before proceed to heat treatment process. The process is known as post spinning treatment process. In this study, oleic acid and the commercial chemical were applied as post treatment spinning chemical. After post spinning treatment, the fibre will be heat treated in 2 temperature zone represent stabilize and pre-carbonized region. The stabilize region is fixed at 250°C and the pre-carbonized region at 500°C. After heat treatment process, the fibre will be mechanically characterized using the low force single column universal tensile machine. Scanning Electron Microscope (SEM) micrograph was used to determine fibre diameter and surface microstructure. From the study, the tensile strength of PAN fiber post treated with oleic acid was lowered almost 50%. For pre carbonized process, PAN fiber post treated with an oleic acid increase by 73%. This show that oleic acid can be used as post spinning treatment chemical in carbon fibre conversion process.

  3. Gene expression profiling in human precision-cut liver slices upon treatment with the FXR agonist obeticholic acid [human

    NARCIS (Netherlands)

    IJssennagger, Noortje; Janssen, Aafke; Mil, van Saskia; Kersten, Sander

    2016-01-01

    Background: The bile acid-activated farnesoid X receptor (FXR) is a nuclear receptor regulating bile acid, glucose and cholesterol homeostasis. Obeticholic acid (OCA; also known as INT-747 or 6α-ethyl-chenodeoxycholic acid), a promising drug for the treatment of non-alcoholic steatohepatitis (NASH)

  4. Gene expression profiling in human precision-cut liver slices upon treatment with the FXR agonist obeticholic acid [mouse

    NARCIS (Netherlands)

    IJssennagger, Noortje; Janssen, Aafke; Kersten, Sander; Mil, van S.W.C.

    2016-01-01

    Background: The bile acid-activated farnesoid X receptor (FXR) is a nuclear receptor regulating bile acid, glucose and cholesterol homeostasis. Obeticholic acid (OCA; also known as INT-747 or 6α-ethyl-chenodeoxycholic acid), a promising drug for the treatment of non-alcoholic steatohepatitis (NASH)

  5. Influencing factors on microbubble ozonation treatment of acid red 3R wastewater

    Directory of Open Access Journals (Sweden)

    Yurong YA

    2017-08-01

    Full Text Available The microbubble ozonation was used to treat acid red 3R wastewater in order to investigate the influencing factors on its performance. The effects of ozone dose, initial acid red 3R concentration and activated carbon on the performance of microbubble ozonation treatment of acid red 3R wastewater are investigated. The decolorization rate, TOC removal rate, pH variation and ozone utilization efficiency in the microbubble ozonation treatment are compared under different treatment conditions. The results indicate that when increasing ozone dose or decreasing initial acid red 3R concentration, both decolorization rate and TOC removal rate of acid red 3R wastewater increase, but ozone utilization efficiency decreases. The coal-based activated carbon shows strong catalytic activity for microbubble ozonation, which could enhance the decolorization rate and TOC removal rate of acid red 3R wastewater. The better performance of microbubble ozonation treatment is achieved when the ozone dose is 48.3 mg/min and the initial acid red 3R mass concentration is 100 mg/L. Under these conditions, the decolorization efficiency reaches to 100% after treatment for 30 min, the TOC removal efficiency reaches to 78.0% after treatment for 120 min, the reaction rate constant of TOC removal is 0.015 min-1 and the ozone utilization efficiency is higher than 99%. With addition of the coal-based activated carbon of 5 g/L, the decolorization efficiency reaches to 100% after treatment for 15 min, the TOC removal efficiency reaches to 91.2% after treatment for 120 min and the reaction rate constant of TOC removal increases to 0037 min-1.The accumulation and following degradation of intermediate products of small molecule organic acid happens during treatment process, and as a result, the solution pH decreases initially and then increases. Therefore, the optimization of influencing factors for microbubble ozonation could increase both contaminant removal

  6. Solar sterilization of abscised fruit: a cultural practice to reduce infestations of Anastrepha obliqua around orchards

    Science.gov (United States)

    Abscised mangoes, Mangifera indica L., of several varieties were stored under varying conditions of insolation, including no sun (stored in a laboratory), shade (stored under the shade of a mango tree), full sun (stored in direct view of the sun), and covered in a black plastic bag and stored in dir...

  7. Analysis of Cytokinin Mutants and Regulation of Cytokinin Metabolic Genes Reveals Important Regulatory Roles of Cytokinins in Drought, Salt and Abscisic Acid Responses, and Abscisic Acid Biosynthesis

    Czech Academy of Sciences Publication Activity Database

    Nishiyama, R.; Watanabe, Y.; Werner, T.; Vaňková, Radomíra; Schmülling, T.; Tran, L. S. P.

    2011-01-01

    Roč. 23, č. 6 (2011), s. 2169-2183 ISSN 1040-4651 Institutional research plan: CEZ:AV0Z50380511 Keywords : TRANSGENIC TOBACCO PLANTS * WATER-STRESS * LEAF SENESCENCE Subject RIV: ED - Physiology Impact factor: 8.987, year: 2011

  8. Oral Pantoprazole for Acid Suppression in the Treatment of Patients with Zollinger-Ellison Syndrome

    Directory of Open Access Journals (Sweden)

    Barbara Désir

    2001-01-01

    Full Text Available BACKGROUND: The management of patients with gastric acid hypersecretion due to gastrinoma, usually recognized as Zollinger-Ellison syndrome (ZES, was radically changed 10 years ago by the use of proton pump inhibitors. Surgical treatment now concentrates on tumour excision, and in the majority of patients, gastrectomy is no longer required to prevent complications of acid hypersecretion that can be managed pharmacologically.

  9. Some biochemical reactions of strawberry plants to infection with Botrytis cinerea and salicylic acid treatment

    Directory of Open Access Journals (Sweden)

    Urszula Małolepsza

    2013-12-01

    Full Text Available The reactions of strawberry plants to infection with B. cinerea and treatment with salicylic acid has been studied. Infection of leaves with B. cinerea resulted in early increases in active oxygen species generation, superoxide dismutase and peroxidase activities and phenolic compounds content. Some increases of the above reactions were noticed in plants treated with salicylic acid but not in the plants treated with SA and then later infected with B. cinerea.

  10. Modeling and optimization of ammonia treatment by acidic biochar using response surface methodology

    OpenAIRE

    Narong Chaisongkroh; Juntima Chungsiriporn; Charun Bunyakan

    2012-01-01

    Emission of ammonia (NH3) contaminated waste air to the atmosphere without treatment has affected humans andenvironment. Eliminating NH3 in waste air emitted from industries is considered an environmental requisite. In this study,optimization of NH3 adsorption time using acidic rubber wood biochar (RWBs) impregnated with sulfuric acid (H2SO4) wasinvestigated. The central composite design (CCD) in response surface methodology (RSM) by the Design Expert softwarewas used for designing the experi...

  11. Potential risks of effluent from acid mine drainage treatment plants at abandoned coal mines.

    Science.gov (United States)

    Seo, Jaehwan; Kang, Sung-Wook; Ji, Wonhyun; Jo, Hun-Je; Jung, Jinho

    2012-06-01

    The lethal and sublethal toxicity of effluent from three acid mine drainage treatment plants were monitored from August 2009 to April 2010 using Daphnia magna (reference species) and Moina macrocopa (indigenous species). Acute lethal toxicity was observed in Samma effluent due to incomplete neutralization of acid mine drainages by the successive alkalinity producing system (SAPS). Additionally, there was no significant difference in toxicity values (TU) between D. magna and M. macrocopa (p water bodies.

  12. Omega-3 fatty acids as treatments for mental illness: which disorder and which fatty acid?

    Directory of Open Access Journals (Sweden)

    Sieswerda Lee E

    2007-09-01

    Full Text Available Abstract Background A growing number of observational and epidemiological studies have suggested that mental illness, in particular mood disorders, is associated with reduced dietary intake and/or cellular abundance of omega-3 polyunsaturated fatty acids (PUFA. This has prompted researchers to test the efficacy of omega-3 PUFA in a range of different psychiatric disorders. We have critically reviewed the double blind placebo controlled clinical trials published prior to April 2007 to determine whether omega-3 PUFA are likely to be efficacious in these disorders. Results Most trials involved a small number of participants but were largely well designed. Omega-3 PUFA were well tolerated by both children and adults with mild gastrointestinal effects being the only consistently reported adverse event. For schizophrenia and borderline personality disorder we found little evidence of a robust clinically relevant effect. In the case of attention deficit hyperactivity disorder and related disorders, most trials showed at most small benefits over placebo. A limited meta-analysis of these trials suggested that benefits of omega-3 PUFA supplementation may be greater in a classroom setting than at home. Some evidence indicates that omega-3 PUFA may reduce symptoms of anxiety although the data is preliminary and inconclusive. The most convincing evidence for beneficial effects of omega-3 PUFA is to be found in mood disorders. A meta-analysis of trials involving patients with major depressive disorder and bipolar disorder provided evidence that omega-3 PUFA supplementation reduces symptoms of depression. Furthermore, meta-regression analysis suggests that supplementation with eicosapentaenoic acid may be more beneficial in mood disorders than with docosahexaenoic acid, although several confounding factors prevented a definitive conclusion being made regarding which species of omega-3 PUFA is most beneficial. The mechanisms underlying the apparent efficacy of

  13. Effects of citric acid treatment on the Ca, P and Mg contents of human dental roots.

    Science.gov (United States)

    Hennequin, M; Douillard, Y

    1995-07-01

    An electron microprobe analyser associated with a scanning electronic microscope was used to measure Ca, P and Mg contents of the human dental root hard tissues, before and after a citric acid treatment (pH = 1). The measurements were made on transverse sections through the cervical 1/3 of the molar roots. The measurements were performed at the following 8 levels: the internal cementum, the cementum-dentine junction, cementum-related dentine, 4 external dentine levels located at 220 microns, 420 microns, 620 microns and 820 microns from the cementum-dentine junction, and finally the juxta-pulpal dentine. After the citric acid treatment, the losses in Ca and P, but not in Mg, varied significantly with the level; an acid-resistant dentine layer of approximately 600 microns was found under the cementum-dentine junction. An increase in the Ca/P ratio was also observed in this layer. Since this external dentine zone is less demineralized by the citric acid than the underlying dentine, the collagen matrix in this region may also be less exposed. These differences in the response to citric acid that depend on the distance from the root surface may explain the unpredictability of periodontal healing after citric acid treatment of diseased root surfaces, because the amount of tissue removed during root planing is not constant.

  14. Carglumic acid: an additional therapy in the treatment of organic acidurias with hyperammonemia?

    Directory of Open Access Journals (Sweden)

    Guffon Nathalie

    2008-01-01

    Full Text Available Abstract Background Hyperammonemia in patients with methylmalonic aciduria (MMA and propionic aciduria (PA is caused by accumulation of propionyl-CoA which decreases the synthesis of N-acetyl-glutamate, the natural activator of carbamyl phosphate synthetase 1. A treatment approach with carglumic acid, the structural analogue of N-acetyl-glutamate, has been proposed to decrease high ammonia levels encountered in MMA and PA crises. Case presentation We described two patients (one with MMA and one with PA with hyperammonemia at diagnosis. Carglumic acid, when associated with standard treatment of organic acidurias, may be helpful in normalizing the ammonia level. Conclusion Even though the usual treatment which decreases toxic metabolites remains the standard, carglumic acid could be helpful in lowering plasma ammonia levels over 400 micromol/L more rapidly.

  15. Comparison of efficacy of products containing azelaic acid in melasma treatment.

    Science.gov (United States)

    Mazurek, Klaudia; Pierzchała, Ewa

    2016-09-01

    Melasma is one of the most frequently diagnosed hyperpigmentation changes on the skin of women's faces. Nearly 30% of women using oral estrogen therapy struggle with this problem. A common way of reducing melasma is the application of azelaic acid products. Comparison of efficacy of three dermocosmetic products, containing azelaic acid, in the reduction in melasma for women aged 35-55. A group of 60 women diagnosed with melasma were divided into three even, twenty-person subgroups. Each subgroup was assigned one dermocosmetic product containing azelaic acid. For 24 weeks, the patients applied the assigned product twice a day. The level of the colorant within the hyperpigmentation was marked before the treatment, after 1 month, after 3 months, and after 6 months of therapy. The pigmentation was measured using Mexameter(®) (Courage + Khazaka electronic, Germany). In addition, during each inspection, the patients' level of hydration, elasticity, and intensity of erythema was checked using Corneometer(®) , Reviscometer(®) . All dermocosmetics containing azelaic acid that were applied significantly contributed to the reduction in pigment in the pigmentary lesion. The largest decrease in the amount of pigment was observed in the first 3 months of use of the products. A combination containing 20% azelaic acid and mandelic acid, phytic acid, 4N-butyl resorcinol, and ferulic acid proved to be the most effective dermocosmetic III (Sesderma, Valencia, Spain). Dermocosmetics containing azelaic acid significantly contribute to the clearing of melasma. The effect depends on the treatment time, the acid concentration, and addition of other components. © 2016 Wiley Periodicals, Inc.

  16. Intravesical hyaluronic acid treatment improves bacterial cystitis and reduces cystitis-induced hypercontractility in rats.

    Science.gov (United States)

    Yıldız, Nurdan; Alpay, Harika; Tuğtepe, Halil; Özdemir Kumral, Zarife Nigar; Akakın, Dilek; İlki, Arzu; Şener, Göksel; Ç Yeğen, Berrak

    2015-06-01

    To investigate the effect of intravesical hyaluronic acid on Escherichia coli-induced cystitis and cystitis-induced hypercontractility in rats. Bacterial cystitis was induced in Wistar female rats by intravesical inoculation of E. coli. Isotonic saline was instilled in the control group (n = 6). The rats were either non-treated, treated with gentamycin (4 mg/kg, 5 days) or treated intravesically with hyaluronic acid (0.5 mL, 0.5%). On the eighth day, the bladder tissues were excised for histological examination, and the measurements of myeloperoxidase, superoxide dismutase and catalase activities. Contraction/relaxation responses to carbachol, isoprotrenol and papaverine were studied. Tissue myeloperoxidase activity was increased, but superoxide dismutase and catalase activities were decreased in bacterial cystitis, while hyaluronic acid treatment reversed these changes. In the hyaluronic acid-treated group, healing of the uroepithelium was observed, while decreased inflammatory cell infiltration was obvious in gentamycin-treated group. E. coli-induced cystitis in all rats resulted in increased contraction responses to carbachol compared with controls (P hyaluronic acid, but not gentamycin, significantly (P hyaluronic acid, in addition to its supportive role in the healing of the epithelium, seems to lower the increased threshold for contraction and to reduce oxidative stress. These findings support a potential role for hyaluronic acid in the treatment of bacterial cystitis. © 2015 The Japanese Urological Association.

  17. The Efficacy and Safety of Azelaic Acid 15% Foam in the Treatment of Truncal Acne Vulgaris.

    Science.gov (United States)

    Hoffman, Lauren K; Del Rosso, James Q; Kircik, Leon H

    2017-06-01

    INTRODUCTION: Truncal acne is often associated with facial acne, but there are fewer options for an effective topical treatment on the trunk. Given the advent of foam formulations with enhanced percutaneous absorption and convenient application due to easy spreadability on skin, the previously held idea that effective treatment of truncal acne requires oral treatment is challenged. Azelaic acid cream has been previously approved for acne vulgaris, thus azelaic acid foam may be a viable treatment option for truncal acne. STUDY DESIGN: A single-center, open label pilot study was conducted to investigate the efficacy and safety of azelaic acid 15% foam as a treatment modality for moderate truncal acne. Use for facial acne was also allowed and monitored during the study. RESULTS: Twice-daily application of azelaic acid 15% foam to affected areas resulted in a 1-grade reduction in truncal investigator global assessment (IGA) scores in nearly all patients (16/18). Eight out of 18 patients (44%) were rated as Clear or Almost Clear in the trunk by the end of the study. There were also improvements in facial IGA scores; 9 of 18 patients (50%) exhibited a 1-grade improvement in IGA scores and 11 of 18 were Clear or Almost Clear by the end of the study. A significant reduction in lesion counts was found throughout the study and the medication was well tolerated. CONCUSION: Azelaic acid 15% foam was effective in treating moderate truncal acne and facial acne in this pilot study. Given the efficacy and convenience of the foam vehicle, azelaic acid may be considered as a viable option for treatment of acne vulgaris, including on the trunk. Further studies are suggested in a larger population of patients, including adult females with acne. J Drugs Dermatol. 2017;16(6):534-538..

  18. Modulating protein adsorption onto hydroxyapatite particles using different amino acid treatments.

    Science.gov (United States)

    Lee, Wing-Hin; Loo, Ching-Yee; Van, Kim Linh; Zavgorodniy, Alexander V; Rohanizadeh, Ramin

    2012-05-07

    Hydroxyapatite (HA) is a material of choice for bone grafts owing to its chemical and structural similarities to the mineral phase of hard tissues. The combination of osteogenic proteins with HA materials that carry and deliver the proteins to the bone-defective areas will accelerate bone regeneration. The study investigated the treatment of HA particles with different amino acids such as serine (Ser), asparagine (Asn), aspartic acid (Asp) and arginine (Arg) to enhance the adsorption ability of HA carrier for delivering therapeutic proteins to the body. The crystallinity of HA reduced when amino acids were added during HA preparation. Depending on the types of amino acid, the specific surface area of the amino acid-functionalized HA particles varied from 105 to 149 m(2) g(-1). Bovine serum albumin (BSA) and lysozyme were used as model proteins for adsorption study. The protein adsorption onto the surface of amino acid-functionalized HA depended on the polarities of HA particles, whereby, compared with lysozyme, BSA demonstrated higher affinity towards positively charged Arg-HA. Alternatively, the binding affinity of lysozyme onto the negatively charged Asp-HA was higher when compared with BSA. The BSA and lysozyme adsorptions onto the amino acid-functionalized HA fitted better into the Freundlich than Langmuir model. The amino acid-functionalized HA particles that had higher protein adsorption demonstrated a lower protein-release rate.

  19. Citric acid facilitated thermal treatment: An innovative method for the remediation of mercury contaminated soil

    International Nuclear Information System (INIS)

    Ma, Fujun; Peng, Changsheng; Hou, Deyi; Wu, Bin; Zhang, Qian; Li, Fasheng; Gu, Qingbao

    2015-01-01

    Highlights: • Hg content was reduced to <1.5 mg/kg when treated at 400 °C with citric acid. • The treated soil retained most of its original soil physicochemical properties. • Proton provided by citric acid facilitates thermal removal of mercury. • This thermal treatment method is expected to reduce energy input by 35%. - Abstract: Thermal treatment is a promising technology for the remediation of mercury contaminated soils, but it often requires high energy input at heating temperatures above 600 °C, and the treated soil is not suitable for agricultural reuse. The present study developed a novel method for the thermal treatment of mercury contaminated soils with the facilitation of citric acid (CA). A CA/Hg molar ratio of 15 was adopted as the optimum dosage. The mercury concentration in soils was successfully reduced from 134 mg/kg to 1.1 mg/kg when treated at 400 °C for 60 min and the treated soil retained most of its original soil physiochemical properties. During the treatment process, CA was found to provide an acidic environment which enhanced the volatilization of mercury. This method is expected to reduce energy input by 35% comparing to the traditional thermal treatment method, and lead to agricultural soil reuse, thus providing a greener and more sustainable remediation method for treating mercury contaminated soil in future engineering applications.

  20. Citric acid facilitated thermal treatment: An innovative method for the remediation of mercury contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Fujun [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Peng, Changsheng [The Key Lab of Marine Environmental Science and Ecology, Ministry of Education, Ocean University of China, Qingdao 266100 (China); Hou, Deyi [Geotechnical and Environmental Research Group, Department of Engineering, University of Cambridge, Cambridge CB2 1PZ (United Kingdom); Wu, Bin; Zhang, Qian; Li, Fasheng [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Gu, Qingbao, E-mail: guqb@craes.org.cn [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China)

    2015-12-30

    Highlights: • Hg content was reduced to <1.5 mg/kg when treated at 400 °C with citric acid. • The treated soil retained most of its original soil physicochemical properties. • Proton provided by citric acid facilitates thermal removal of mercury. • This thermal treatment method is expected to reduce energy input by 35%. - Abstract: Thermal treatment is a promising technology for the remediation of mercury contaminated soils, but it often requires high energy input at heating temperatures above 600 °C, and the treated soil is not suitable for agricultural reuse. The present study developed a novel method for the thermal treatment of mercury contaminated soils with the facilitation of citric acid (CA). A CA/Hg molar ratio of 15 was adopted as the optimum dosage. The mercury concentration in soils was successfully reduced from 134 mg/kg to 1.1 mg/kg when treated at 400 °C for 60 min and the treated soil retained most of its original soil physiochemical properties. During the treatment process, CA was found to provide an acidic environment which enhanced the volatilization of mercury. This method is expected to reduce energy input by 35% comparing to the traditional thermal treatment method, and lead to agricultural soil reuse, thus providing a greener and more sustainable remediation method for treating mercury contaminated soil in future engineering applications.

  1. Optimisation of dilute acid pre-treatment of artisan rice hulls for ethanol production

    International Nuclear Information System (INIS)

    Lopez, Yoney; Martin, Carlos; Gullon, Beatriz; Parajo, Juan Carlos

    2011-01-01

    Rice hulls are potential low-cost feedstocks for fuel ethanol production in many countries. In this work, the dilute-acid pre-treatment of artisan rice hulls was investigated using a central composite rotatable experimental design. The experimental variables were temperature (140-210 C), biomass load (5-20%) and sulphuric acid concentration (0.5-1.5 g per 100 g of reaction mixture). A total of 16 experimental runs, including a 23-plan, two replicates at the central point and six star points, were carried out. Low temperatures were found to be favourable for the hydrolysis of xylan and of the easily hydrolyzable glucan fraction. High glucose formation (up to 15.3 g/100 g), attributable to starch hydrolysis, was detected in the hydrolysates obtained under the least severe pre-treatment conditions. Using the experimental results, several models for predicting the effect of the operational conditions on the yield of pretreated solids, xylan and glucan conversion upon pre-treatment, and on enzymatic convertibility of cellulose were developed. Optimum results were predicted for the conversion of easily-hydrolyzable glucan in the material pretreated at 140.7 C, and for the enzymatic saccharification of cellulose in the material pretreated at 169 C. These results suggested the use of two-step acid hydrolysis as future pre-treatment strategy for artisan rice hulls. Key words: Dilute acid hydrolysis, enzymatic hydrolysis, pre-treatment, rice hulls. (author)

  2. Treatment of purified terephthalic acid wastewater using a bio-waste-adsorbent bagasse fly ash (BFA).

    Science.gov (United States)

    Verma, Shilpi; Prasad, Basheshwar; Mishra, Indra Mani

    2017-01-01

    Purified terephthalic acid (PTA) plant of a petrochemical unit generates wastewater having high pollution load. Acid treatment of this wastewater reduces the chemical oxygen demand (COD) load by more than 50%, still leaving substantial COD load (>1500 mg/L) which should be removed. The present study reports on the use of a bio-waste-adsorbent bagasse fly ash (BFA) for the reduction of COD and other recalcitrant acids from this wastewater. The BFA showed basic character and was mesoporous with a BET specific surface area of 82.4 m 2 /g. Optimum conditions for the adsorptive treatment of acid-pretreated PTA wastewater were found to be as follows: initial pH (pH i ) = 4, BFA dosage = 15 g/L, and contact time = 3 h. Adsorption treatment resulted in 58.2% removal of COD, 96.3% removal of terephthalic acid (TA), and 99.9% removal of benzoic acid (BA). TA and BA were removed from the pretreated PTA wastewater through precipitation and sedimentation of un-dissociated acid molecules inside the mesopores of the BFA. The results showed that the COD removed by the BFA followed pseudo-second-order kinetics. Equilibrium sorption data were best correlated by the Freundlich isotherm. The process of adsorptive removal of COD was found to be exothermic. The change in the Gibbs free energy was found to be negative, suggesting that the adsorption process is spontaneous and feasible for the treatment of PTA wastewater.

  3. Effect of Putrescine Treatment on Chilling Injury, Fatty Acid Composition and Antioxidant System in Kiwifruit.

    Science.gov (United States)

    Yang, Qingzhen; Wang, Feng; Rao, Jingping

    2016-01-01

    We investigated the effects of different concentrations (0, 1, 2 and 4 mM) of putrescine on chilling injury, fruit quality, ethylene production rate, fatty acid composition and the antioxidant system of cold-stored kiwifruit (Actinidia chinensis Planch. var. chinensis 'Hongyang'). We achieved a significant decrease in ethylene production, maintained fruit quality and alleviated chilling injury during storage via treatment with 2 mM putrescine. Furthermore, putrescine treatment inhibited increases in superoxide anion production rate and H2O2 concentration, while maintaining higher membrane lipid unsaturation as well as increased activities of superoxide dismutase and catalase. In addition, putrescine treatment enhanced the activities of antioxidant enzymes related to the ascorbate-glutathione cycle while causing higher levels of ascorbic acid and reduced glutathione. Our results suggest that induced tolerance against chilling injury via putrescine treatment in cold-stored kiwifruit may be due to enhanced antioxidant activity, increased unsaturation of membrane lipids, and inhibited ethylene production.

  4. Quality and antioxidant properties on sweet cherries as affected by preharvest salicylic and acetylsalicylic acids treatments.

    Science.gov (United States)

    Giménez, María José; Valverde, Juan Miguel; Valero, Daniel; Guillén, Fabián; Martínez-Romero, Domingo; Serrano, María; Castillo, Salvador

    2014-10-01

    The effects of salicylic acid (SA) or acetylsalicylic acid (ASA) treatments during on-tree cherry growth and ripening on fruit quality attributes, especially those related with the content on bioactive compounds and antioxidant activity were analysed in this research. For this purpose, two sweet cherry cultivars, 'Sweet Heart' and 'Sweet Late', were used and SA or ASA treatments, at 0.5, 1.0 and 2.0mM concentrations, were applied at three key points of fruit development (pit hardening, initial colour changes and onset of ripening). These treatments increased fruit weight and ameliorated quality attributes at commercial harvest, and led to cherries with higher concentration in total phenolics and in total anthocyanins, as well as higher antioxidant activity, in both hydrophilic and lipophilic fractions. Thus, preharvest treatments with SA or ASA could be promising tools to improve sweet cherry quality and health beneficial effects for consumers. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. The importance of γ-linolenic acid in the prevention and treatment

    Directory of Open Access Journals (Sweden)

    Małgorzata Białek

    2015-07-01

    Full Text Available The etiology of diet-related disorders is closely associated with dietary factors. A special role is attributed to intake of fat and fatty acid profile, both quantitative and qualitative. For prevention and treatment of the abovementioned diseases a proper supply of unsaturated fatty acids plays a significant role, because of their particular importance to health. γ-Linolenic acid (GLA, with three double bonds in the carbon chain, also known as all-cis 6,9,12-octadecatrienoic acid, belongs to the n-6 family of fatty acids. It plays biologically important functions in the human body, such as being a substrate for eicosanoids synthesis, involvement in the transport and oxidation of cholesterol, and being one of the components of lipid membrane. Its inadequate dietary intake or impaired formation is the cause of many inflammatory and degenerative diseases. A rich source of this fatty acid is vegetable oils, until recently used mainly in folk medicine. Nowadays, studies conducted both in animal models and in humans suggest its health-promoting properties in the prevention and treatment of atopic dermatitis, cardiovascular diseases, diabetes, cancers and rheumatoid arthritis.

  6. Removal of cyanobacterial amino acids in water treatment by activated carbon adsorption

    Czech Academy of Sciences Publication Activity Database

    Čermáková, Lenka; Kopecká, Ivana; Pivokonský, Martin; Pivokonská, Lenka; Janda, V.

    2017-01-01

    Roč. 173, č. 1 (2017), s. 330-338 ISSN 1383-5866 Institutional support: RVO:67985874 Keywords : amino acids * activated carbon * adsorption * algal organic matter * water treatment * coagulation * microcystis aeruginosa * peptides/proteins * permanganate pre-oxidation * water treatment Subject RIV: DJ - Water Pollution ; Quality OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 3.359, year: 2016

  7. Citric acid treatment of chronic nonhealing ulcerated tophaceous gout with bursitis.

    Science.gov (United States)

    Nagoba, Basavaraj S; Punpale, Ajay; Poddar, Ashok; Suryawanshi, Namdev M; Swami, Ganesh A; Selkar, Sohan P

    2013-12-01

    The ulceration associated with gout tophi is very difficult to treat because of impaired and halted local inflammatory response resulting from the gout treatment regimen. We report chronic nonhealing tophaceous gout with bursitis in an 80-year-old male, not responding to conventional treatment modality for months together. This nonhealing ulcer was treated successfully with local application of 3% citric acid ointment for 22 days.

  8. Removal of cyanobacterial amino acids in water treatment by activated carbon adsorption

    Czech Academy of Sciences Publication Activity Database

    Čermáková, Lenka; Kopecká, Ivana; Pivokonský, Martin; Pivokonská, Lenka; Janda, V.

    2017-01-01

    Roč. 173, č. 1 (2017), s. 330-338 ISSN 1383-5866 Institutional support: RVO:67985874 Keywords : amino acids * activated carbon * adsorption * algal organic matter * water treatment * coagulation * microcystis aeruginosa * peptides/proteins * permanganate pre- oxidation * water treatment Subject RIV: DJ - Water Pollution ; Quality OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 3.359, year: 2016

  9. Endoscopic treatment of vesicoureteral reflux with polyacrylate polyalcohol copolymer and dextranomer/hyaluronic acid in adults

    OpenAIRE

    Turk,Akif; Selimoglu,Ahmet; Demir,Kadir; Celik,Osman; Saglam,Erkin; Tarhan,Fatih

    2014-01-01

    Purpose Aim of this study is to examine the effectiveness of dextranomer/hyaluronic acid copolymer and polyacrylate polyalcohol copolymer in endoscopic treatment of vesicoureteral reflux disease in adult patients with and without chronic renal failure. Materials and Methods Thirty two patients (12 female, 20 male) with a total of 50 renal units were treated for vesicoureteral reflux. There were 26 (81%) chronic renal failure patients. The success of treatment was evaluated by voiding cyst...

  10. Where to from here? The treatment of impetigo in children as resistance to fusidic acid emerges.

    Science.gov (United States)

    Vogel, Alison; Lennon, Diana; Best, Emma; Leversha, Alison

    2016-10-14

    Admissions for skin and soft-tissue infections have been increasing steadily in children and in the general population. Concerns have been raised recently about the increasing widespread use of topical fusidic acid and concurrent increase of fusidic acid-resistant Staphylococcus aureus. Fusidic acid resistance and methicillin resistant Staphylococcus aureus (MRSA) are both more prevalent in youngest age group (<5 year-olds) and particularly in the North island. In New Zealand, fusidic acid is recommended for treatment of minor impetigo and is the only fully-funded topical antibiotic. The evidence base for alternative treatment strategies for mild impetigo is limited. Most children with impetigo in the current Counties Manukau skin and sore throat schools programme received care with wound management with only a few requiring escalation. An upcoming randomised controlled trial comparing topical hydrogen peroxide cream, topical fusidic acid and wound management only (clean and cover) will help provide evidence about the effectiveness of alternative treatments in the New Zealand setting.

  11. Treatment of infectious skin defects or ulcers with electrolyzed strong acid aqueous solution.

    Science.gov (United States)

    Sekiya, S; Ohmori, K; Harii, K

    1997-01-01

    A chronic ulcer with an infection such as methicillin-resistant Staphylococcus aureus is hard to heal. Plastic and reconstructive surgeons often encounter such chronic ulcers that are resistant to surgical or various conservative treatments. We applied conservative treatment using an electrolyzed strong acid aqueous solution and obtained satisfactory results. The lesion was washed with the solution or soaked in a bowl of the solution for approximately 20 min twice a day. Fresh electrolyzed strong acid aqueous solution is unstable and should be stored in a cool, dark site in a sealed bottle. It should be used within a week after it has been produced. Here we report on 15 cases of infectious ulcers that were treated by electrolyzed strong acid aqueous solution. Of these cases, 7 patients were healed, 3 were granulated, and in 5, infection subsided. In most cases the lesion became less reddish and less edematous. Discharge or foul odor from the lesion was decreased. Electrolyzed strong acid aqueous solution was especially effective for treating a chronic refractory ulcer combined with diabetes melitus or peripheral circulatory insufficiency. This clinically applied therapy of electrolyzed strong acid aq