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Sample records for aba levels increased

  1. Chemical inhibition of potato ABA-8'-hydroxylase activity alters in vitro and in vivo ABA metabolism and endogenous ABA levels but does not affect potato microtuber dormancy duration.

    PubMed

    Suttle, Jeffrey C; Abrams, Suzanne R; De Stefano-Beltrán, Luis; Huckle, Linda L

    2012-09-01

    The effects of azole-type P450 inhibitors and two metabolism-resistant abscisic acid (ABA) analogues on in vitro ABA-8'-hydroxylase activity, in planta ABA metabolism, endogenous ABA content, and tuber meristem dormancy duration were examined in potato (Solanum tuberosum L. cv. Russet Burbank). When functionally expressed in yeast, three potato CYP707A genes were demonstrated to encode enzymatically active ABA-8'-hydroxylases with micromolar affinities for (+)-ABA. The in vitro activity of the three enzymes was inhibited by the P450 azole-type inhibitors ancymidol, paclobutrazol, diniconazole, and tetcyclasis, and by the 8'-acetylene- and 8'-methylene-ABA analogues, with diniconazole and tetcyclasis being the most potent inhibitors. The in planta metabolism of [(3)H](±)-ABA to phaseic acid and dihydrophaseic acid in tuber meristems was inhibited by diniconazole, tetcyclasis, and to a lesser extent by 8'-acetylene- and 8'-methylene-ABA. Continuous exposure of in vitro generated microtubers to diniconazole resulted in a 2-fold increase in endogenous ABA content and a decline in dihydrophaseic acid content after 9 weeks of development. Similar treatment with 8'-acetylene-ABA had no effects on the endogenous contents of ABA or phaseic acid but reduced the content of dihydrophaseic acid. Tuber meristem dormancy progression was determined ex vitro in control, diniconazole-, and 8'-acetylene-ABA-treated microtubers following harvest. Continuous exposure to diniconazole during microtuber development had no effects on subsequent sprouting at any time point. Continuous exposure to 8'-acetylene-ABA significantly increased the rate of microtuber sprouting. The results indicate that, although a decrease in ABA content is a hallmark of tuber dormancy progression, the decline in ABA levels is not a prerequisite for dormancy exit and the onset of tuber sprouting.

  2. Wounding of potato tubers induces increases in ABA biosynthesis and catabolism and alters expression of ABA metabolic genes.

    PubMed

    Suttle, Jeffrey C; Lulai, Edward C; Huckle, Linda L; Neubauer, Jonathan D

    2013-04-15

    The effects of physical wounding on ABA biosynthesis and catabolism and expression of genes encoding key ABA metabolic enzymes were determined in potato tubers. An increase in ABA and ABA metabolite content was observed 48h after wounding and remained elevated through 96h. Wounding induced dramatic increases in the expression of the ABA metabolic genes encoding zeaxanthin epoxidase (ZEP), 9-cis-epoxycarotenoid dioxygenase (NCED), and ABA-8'-hydroxylase. Although the patterns of wound-induced expression of individual genes varied, increased gene expression was observed within 3h of wounding and remained elevated through 96h. An apparent correlation between expression of the gene encoding ZEP and the increase in ABA content suggested that the wound-induced increase in ABA biosynthesis was regulated by both substrate availability and increased NCED activity. Suppression of wound-induced jasmonic acid accumulation by rinsing the wounded tissue with water did not inhibit the subsequent increase in ABA content. Exogenous ethylene completely suppressed the wound-induced increase in ABA content and dramatically reduced wound-induced up-regulation of ABA metabolic genes. This study is the first to identify the molecular bases for increased ABA accumulation following physical trauma in potato tubers and highlights the complex physiological interactions between various wound-induced hormones.

  3. Grafting cucumber onto luffa improves drought tolerance by increasing ABA biosynthesis and sensitivity

    PubMed Central

    Liu, Shanshan; Li, Hao; Lv, Xiangzhang; Ahammed, Golam Jalal; Xia, Xiaojian; Zhou, Jie; Shi, Kai; Asami, Tadao; Yu, Jingquan; Zhou, Yanhong

    2016-01-01

    Balancing stomata-dependent CO2 assimilation and transpiration is a key challenge for increasing crop productivity and water use efficiency under drought stress for sustainable crop production worldwide. Here, we show that cucumber and luffa plants with luffa as rootstock have intrinsically increased water use efficiency, decreased transpiration rate and less affected CO2 assimilation capacity following drought stress over those with cucumber as rootstock. Drought accelerated abscisic acid (ABA) accumulation in roots, xylem sap and leaves, and induced the transcript of ABA signaling genes, leading to a decreased stomatal aperture and transpiration in the plants grafted onto luffa roots as compared to plants grafted onto cucumber roots. Furthermore, stomatal movement in the plants grafted onto luffa roots had an increased sensitivity to ABA. Inhibition of ABA biosynthesis in luffa roots decreased the drought tolerance in cucumber and luffa plants. Our study demonstrates that the roots of luffa have developed an enhanced ability to sense the changes in root-zone moisture and could eventually deliver modest level of ABA from roots to shoots that enhances water use efficiency under drought stress. Such a mechanism could be greatly exploited to benefit the agricultural production especially in arid and semi-arid areas. PMID:26832070

  4. Ascorbate Alleviates Fe Deficiency-Induced Stress in Cotton (Gossypium hirsutum) by Modulating ABA Levels.

    PubMed

    Guo, Kai; Tu, Lili; Wang, Pengcheng; Du, Xueqiong; Ye, Shue; Luo, Ming; Zhang, Xianlong

    2016-01-01

    Fe deficiency causes significant losses to crop productivity and quality. To understand better the mechanisms of plant responses to Fe deficiency, we used an in vitro cotton ovule culture system. We found that Fe deficiency suppressed the development of ovules and fibers, and led to tissue browning. RNA-seq analysis showed that the myo-inositol and galacturonic acid pathways were activated and cytosolic APX (ascorbate peroxidase) was suppressed in Fe-deficient treated fibers, which increased ASC (ascorbate) concentrations to prevent tissue browning. Suppression of cytosolic APX by RNAi in cotton increased ASC contents and delayed tissue browning by maintaining ferric reduction activity under Fe-deficient conditions. Meanwhile, APX RNAi line also exhibited the activation of expression of iron-regulated transporter (IRT1) and ferric reductase-oxidase2 (FRO2) to adapt to Fe deficiency. Abscisic acid (ABA) levels were significantly decreased in Fe-deficient treated ovules and fibers, while the upregulated expression of ABA biosynthesis genes and suppression of ABA degradation genes in Fe-deficient ovules slowed down the decreased of ABA in cytosolic APX suppressed lines to delay the tissue browning. Moreover, the application of ABA in Fe-deficient medium suppressed the development of tissue browning and completely restored the ferric reduction activity. In addition, ABA 8'-hydroxylase gene (GhABAH1) overexpressed cotton has a decreased level of ABA and shows more sensitivity to Fe deficiency. Based on the results, we speculate that ASC could improve the tolerance to Fe deficiency through activating Fe uptake and maintaining ABA levels in cotton ovules and fibers, which in turn reduces symptom formation.

  5. Ascorbate Alleviates Fe Deficiency-Induced Stress in Cotton (Gossypium hirsutum) by Modulating ABA Levels

    PubMed Central

    Guo, Kai; Tu, Lili; Wang, Pengcheng; Du, Xueqiong; Ye, Shue; Luo, Ming; Zhang, Xianlong

    2017-01-01

    Fe deficiency causes significant losses to crop productivity and quality. To understand better the mechanisms of plant responses to Fe deficiency, we used an in vitro cotton ovule culture system. We found that Fe deficiency suppressed the development of ovules and fibers, and led to tissue browning. RNA-seq analysis showed that the myo-inositol and galacturonic acid pathways were activated and cytosolic APX (ascorbate peroxidase) was suppressed in Fe-deficient treated fibers, which increased ASC (ascorbate) concentrations to prevent tissue browning. Suppression of cytosolic APX by RNAi in cotton increased ASC contents and delayed tissue browning by maintaining ferric reduction activity under Fe-deficient conditions. Meanwhile, APX RNAi line also exhibited the activation of expression of iron-regulated transporter (IRT1) and ferric reductase–oxidase2 (FRO2) to adapt to Fe deficiency. Abscisic acid (ABA) levels were significantly decreased in Fe-deficient treated ovules and fibers, while the upregulated expression of ABA biosynthesis genes and suppression of ABA degradation genes in Fe-deficient ovules slowed down the decreased of ABA in cytosolic APX suppressed lines to delay the tissue browning. Moreover, the application of ABA in Fe-deficient medium suppressed the development of tissue browning and completely restored the ferric reduction activity. In addition, ABA 8′-hydroxylase gene (GhABAH1) overexpressed cotton has a decreased level of ABA and shows more sensitivity to Fe deficiency. Based on the results, we speculate that ASC could improve the tolerance to Fe deficiency through activating Fe uptake and maintaining ABA levels in cotton ovules and fibers, which in turn reduces symptom formation. PMID:28101095

  6. Putrescine as a signal to modulate the indispensable ABA increase under cold stress

    PubMed Central

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

    2009-01-01

    Polyamines have been found to correlate frequently with biotic and abiotic insults, and their functional involvement in the plant responses to several stresses has been shown genetically with both gain and loss of function mutations. In spite of a large body of physiological and genetic data, the mode of action for polyamines at the molecular level still remains elusive. We have recently performed a detailed integrated analysis of polyamine metabolism under cold stress by means of metabolic studies, quantitative gene expression analyses, and gene inactivations, to characterize in more detail the role of polyamines in response to low temperature. Our data show a unique accumulation profile for putrescine compared to other polyamines, with a progressive increase upon cold stress treatment coincident with a similar transcriptional upregulation for the two arginine decarboxylase genes ADC1 and ADC2. Loss of function mutants adc1 and adc2 display reduced freezing tolerance and alterations in ABA content and ABA-dependent signalling pathways under low temperature, compared to wild type plants. Phenotypical reverse complementation tests for both adc and ABA-defective mutants support our conclusion that putrescine modulates ABA biosynthesis at the transcriptional level in response to low temperature thus uncovering a novel mode of action for polyamines as regulators of hormone biosynthesis. PMID:19721755

  7. The wheat ABA hypersensitive ERA8 mutant is associated with increased preharvest sprouting tolerance and altered hormone accumulation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat preharvest sprouting (PHS) is the germination of mature grain on the mother plant when rain occurs before harvest. Higher abscisic acid (ABA) hormone levels and sensitivity are associated with higher seed dormancy and PHS tolerance. Consistent with this, the ABA hypersensitive ERA8 (Enhanced...

  8. Spin and valley resolved Landau level crossing in tri-layer ABA stacked graphene

    NASA Astrophysics Data System (ADS)

    Datta, Biswajit; Gupta, Vishakha; Borah, Abhinandan; Watanabe, Kenji; Taniguchi, Takashi; Deshmukh, Mandar

    We present quantum Hall measurements on a high quality encapsulated tri-layer graphene device. Low temperature field effect mobility of this device is around 500,000 cm2/Vs and we see SdH oscillations at a magnetic field as low as 0.3 T. Quantum Hall measurements confirm that the chosen tri layer graphene is Bernal (ABA) stacked. Due to the presence of both mass-less monolayer like Dirac fermions and massive bi-layer like Dirac fermions in Bernal stacked tri-layer graphene, there are Landau level crossings between monolayer and bi-layer bands in quantum Hall regime. Although most of the Landau Level crossings are predominantly present on the electron sides, we also observe signatures of the crossings on the hole side. This behaviour is consistent with the asymmetry of electron and hole in ABA tri-layer graphene. We observe a series of crossings of the spin and valley resolved Landau Levels.

  9. Increased ABA sensitivity results in higher seed dormancy in soft white spring wheat cultivar ‘Zak’

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As a strategy to increase the seed dormancy of soft white wheat, mutants with increased sensitivity to the plant hormone abscisic acid (ABA) were identified in mutagenized grain of soft white spring wheat ‘Zak”. Lack of seed dormancy is correlated with increased susceptibility to preharvest sprouti...

  10. Registration of Zak ERA8 soft white spring wheat germplasm with enhanced response to ABA and increased seed dormancy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ZakERA8 is a unique mutant line selected from mutagenized soft white spring 'Zak' that has increased seed dormancy as a result of enhanced responsiveness to the plant hormone abscisic acid (ABA) during germination. This germplasm was developed by USDA-ARS, Pullman, WA in collaboration with Washingt...

  11. Involvement of root ABA and hydraulic conductivity in the control of water relations in wheat plants exposed to increased evaporative demand.

    PubMed

    Kudoyarova, Guzel; Veselova, Svetlana; Hartung, Wolfram; Farhutdinov, Rashit; Veselov, Dmitry; Sharipova, Guzyal

    2011-01-01

    We studied the possible involvement of ABA in the control of water relations under conditions of increased evaporative demand. Warming the air by 3°C increased stomatal conductance and raised transpiration rates of hydroponically grown Triticum durum plants while bringing about a temporary loss of relative water content (RWC) and immediate cessation of leaf extension. However, both RWC and extension growth recovered within 30 min although transpiration remained high. The restoration of leaf hydration and growth were enabled by increased root hydraulic conductivity after increasing the air temperature. The use of mercuric chloride (an inhibitor of water channels) to interfere with the rise on root hydraulic conductivity hindered the restoration of extension growth. Air warming increased ABA content in roots and decreased it in shoots. We propose this redistribution of ABA in favour of the roots which increased the root hydraulic conductivity sufficiently to permit rapid recovery of shoot hydration and leaf elongation rates without the involvement of stomatal closure. This proposal is based on known ability of ABA to increase hydraulic conductivity confirmed in these experiments by measuring the effect of exogenous ABA on osmotically driven flow of xylem sap from the roots. Accumulation of root ABA was mainly the outcome of increased export from the shoots. When phloem transport in air-warmed plants was inhibited by cooling the shoot base this prevented ABA enrichment of the roots and favoured an accumulation of ABA in the shoot. As a consequence, stomata closed.

  12. H2O2 and ABA signaling are responsible for the increased Na+ efflux and water uptake in Gossypium hirsutum L. roots in the non-saline side under non-uniform root zone salinity.

    PubMed

    Kong, Xiangqiang; Luo, Zhen; Dong, Hezhong; Eneji, A Egrinya; Li, Weijiang

    2016-04-01

    Non-uniform root salinity increases the Na(+)efflux, water use, and growth of the root in non-saline side, which may be regulated by some form of signaling induced by the high-salinity side. However, the signaling and its specific function have remained unknown. Using a split-root system to simulate a non-uniform root zone salinity in Gossypium hirsutum L., we showed that the up-regulated expression of sodium efflux-related genes (SOS1, SOS2, PMA1, and PMA2) and water uptake-related genes (PIP1 and PIP2) was possibly involved in the elevated Na(+) efflux and water use in the the roots in the non-saline side. The increased level of indole acetic acid (IAA) in the non-saline side was the likely cause of the increased root growth. Also, the abscisic acid (ABA) and H2O2 contents in roots in the non-saline side increased, possibly due to the increased expression of their key biosynthesis genes, NCED and RBOHC, and the decreased expression of ABA catabolic CYP707A genes. Exogenous ABA added to the non-saline side induced H2O2 generation by up-regulating the RBOHC gene, but this was decreased by exogenous fluridone. Exogenous H2O2 added to the non-saline side reduced the ABA content by down-regulating NCED genes, which can be induced by diphenylene iodonium (DPI) treatment in the non-saline side, suggesting a feedback mechanism between ABA and H2O2.Both exogenous ABA and H2O2 enhanced the expression of SOS1, PIP1;7 ,PIP2;2, and PIP2;10 genes, but these were down-regulated by fluridone and DPI, suggesting that H2O2 and ABA are important signals for increasing root Na(+) efflux and water uptake in the roots in the non-saline side.

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

    PubMed Central

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

    2015-01-01

    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. PMID:25560179

  14. ALA Inhibits ABA-induced Stomatal Closure via Reducing H2O2 and Ca2+ Levels in Guard Cells

    PubMed Central

    An, Yuyan; Liu, Longbo; Chen, Linghui; Wang, Liangju

    2016-01-01

    5-Aminolevulinic acid (ALA), a newly proved natural plant growth regulator, is well known to improve plant photosynthesis under both normal and stressful conditions. However, its underlying mechanism remains largely unknown. Stomatal closure is one of the major limiting factors for photosynthesis and abscisic acid (ABA) is the most important hormone in provoking stomatal closing. Here, we showed that ALA significantly inhibited ABA-induced stomatal closure using wild-type and ALA-overproducing transgenic Arabidopsis (YHem1). We found that ALA decreased ABA-induced H2O2 and cytosolic Ca2+ accumulation in guard cells with stomatal bioassay, laser-scanning confocal microscopy and pharmacological methods. The inhibitory effect of ALA on ABA-induced stomatal closure was similar to that of AsA (an important reducing substrate for H2O2 removal), CAT (a H2O2-scavenging enzyme), DPI (an inhibitor of the H2O2-generating NADPH oxidase), EGTA (a Ca-chelating agent), and AlCl3 (an inhibitor of calcium channel). Furthermore, ALA inhibited exogenous H2O2- or Ca2+-induced stomatal closure. Taken together, we conclude that ALA inhibits ABA-induced stomatal closure via reducing H2O2, probably by scavenging, and Ca2+ levels in guard cells. Moreover, the inhibitive effect of ALA on ABA-induced stomatal closure was further confirmed in the whole plant. Finally, we demonstrated that ALA inhibits stomatal closing, but significantly improves plant drought tolerance. Our results provide valuable information for the promotion of plant production and development of a sustainable low-carbon society. PMID:27148309

  15. ABA and GA3 increase carbon allocation in different organs of grapevine plants by inducing accumulation of non-structural carbohydrates in leaves, enhancement of phloem area and expression of sugar transporters.

    PubMed

    Murcia, Germán; Pontin, Mariela; Reinoso, Herminda; Baraldi, Rita; Bertazza, Gianpaolo; Gómez-Talquenca, Sebastián; Bottini, Rubén; Piccoli, Patricia N

    2016-03-01

    Grape quality for winemaking depends on sugar accumulation and metabolism in berries. Abscisic acid (ABA) and gibberellins (GAs) have been reported to control sugar allocation in economically important crops, although the mechanisms involved are still unknown. The present study tested if ABA and gibberellin A3 (GA3) enhance carbon allocation in fruits of grapevines by modifying phloem loading, phloem area and expression of sugar transporters in leaves and berries. Pot-grown Vitis vinifera cv. Malbec plants were sprayed with ABA and GA3 solutions. The amount of soluble sugars in leaves and berries related to photosynthesis were examined at three points of berry growth: pre-veraison, full veraison and post-veraison. Starch levels and amylase activity in leaves, gene expression of sugar transporters in leaves and berries and phloem anatomy were examined at full veraison. Accumulation of glucose and fructose in berries was hastened in ABA-treated plants at the stage of full veraison, which was correlated with enhancement of Vitis vinifera HEXOSE TRANSPORTER 2 (VvHT2) and Vitis vinifera HEXOSE TRANSPORTER 6 (VvHT6) gene expression, increases of phloem area and sucrose content in leaves. On the other hand, GA3 increased the quantity of photoassimilates delivered to the stem thus increasing xylem growth. In conclusion, stimulation of sugar transport by ABA and GA3 to berries and stems, respectively, was due to build-up of non-structural carbohydrates in leaves, modifications in phloem tissue and modulation in gene expression of sugar transporters.

  16. ABA and cytokinins: challenge and opportunity for plant stress research.

    PubMed

    Verslues, Paul E

    2016-08-01

    Accumulation of the stress hormone abscisic acid (ABA) induces many cellular mechanisms associated with drought resistance. Recent years have seen a rapid advance in our knowledge of how increased ABA levels are perceived by ABA receptors, particularly the PYL/RCAR receptors, but there has been relatively less new information about how ABA accumulation is controlled and matched to stress severity. ABA synthesis and catabolism, conjugation and deconjugation to glucose, and ABA transport all are involved in controlling ABA levels. This highly buffered system of ABA metabolism represents both a challenge and opportunity in developing a mechanistic understanding of how plants detect and respond to drought. Recent data have also shown that direct manipulation of cytokinin levels in transgenic plants has dramatic effect on drought phenotypes and prompted new interest in the role of cytokinins and cytokinin signaling in drought. Both ABA and cytokinins will continue to be major foci of drought research but likely with different trajectories both in terms of basic research and in translational research aimed at increasing plant performance during drought.

  17. WRKY41 controls Arabidopsis seed dormancy via direct regulation of ABI3 transcript levels not downstream of ABA.

    PubMed

    Ding, Zhong Jie; Yan, Jing Ying; Li, Gui Xin; Wu, Zhong Chang; Zhang, Shu Qun; Zheng, Shao Jian

    2014-09-01

    Although seed dormancy is an important agronomic trait, its molecular basis is poorly understood. ABSCISIC ACID INSENSITIVE 3 (ABI3) plays an essential role in the establishment of seed dormancy. Here, we show that the lack of a seed-expressed WRKY transcription factor, WRKY41, confers reduced primary seed dormancy and thermoinhibition, phenotypes resembling those for a lack of ABI3. Loss-of-function abi3-17 and wrky41 alleles also both confer reduced sensitivity to ABA during germination and early seedling growth. Absence of WRKY41 decreases ABI3 transcript abundance in maturing and imbibed seeds, whereas transgenically overexpressing WRKY41 increases ABI3 expression. Moreover, transgenic overexpression of ABI3 completely restores seed dormancy phenotypes on wrky41. ChIP-qPCR and EMSA reveal that WRKY41 binds directly to the ABI3 promoter through three adjacent W-boxes, and a transactivation assay indicates that these W-boxes are essential for ABI3 expression. Whilst RT-qPCR analysis shows that the regulation of ABI3 by WRKY41 is not through ABA and other factors known to promote ABI3 transcription during seed maturation and germination, we also show that high concentrations of ABA might promote negative feedback regulation of WRKY41 expression. Finally, analysis of the wrky41 aba2 double mutant confirms that WRKY41 and ABA collaboratively regulate ABI3 expression and seed dormancy. In summary, our results demonstrate that WRKY41 is an important regulator of ABI3 expression, and hence of seed dormancy.

  18. Root ABA Accumulation in Long-Term Water-Stressed Plants is Sustained by Hormone Transport from Aerial Organs.

    PubMed

    Manzi, Matías; Lado, Joanna; Rodrigo, María Jesús; Zacarías, Lorenzo; Arbona, Vicent; Gómez-Cadenas, Aurelio

    2015-12-01

    The reduced pool of the ABA precursors, β,β-carotenoids, in roots does not account for the substantial increase in ABA content in response to water stress (WS) conditions, suggesting that ABA could be transported from other organs. Basipetal transport was interrupted by stem-girdling, and ABA levels were determined in roots after two cycles of WS induced by transplanting plants to dry perlite. Leaf applications of isotope-labeled ABA and reciprocal grafting of ABA-deficient tomato mutants were used to confirm the involvement of aerial organs on root ABA accumulation. Disruption of basipetal transport reduced ABA accumulation in roots, and this decrease was more severe after two consecutive WS periods. This effect was linked to a sharp decrease in the β,β-carotenoid pool in roots in response to water deficit. Significant levels of isotope-labeled ABA were transported from leaves to roots, mainly in plants subjected to water dehydration. Furthermore, the use of different ABA-deficient tomato mutants in reciprocal grafting combinations with wild-type genotypes confirmed the involvement of aerial organs in the ABA accumulation in roots. In conclusion, accumulation of ABA in roots after long-term WS periods largely relies on the aerial organs, suggesting a reduced ability of the roots to synthesize ABA from carotenoids. Furthermore, plants are able to transport ABA basipetally to sustain high hormone levels in roots.

  19. Inhibition of FUSCA3 degradation at high temperature is dependent on ABA signaling and is regulated by the ABA/GA ratio.

    PubMed

    Chiu, Rex Shun; Saleh, Yazan; Gazzarrini, Sonia

    2016-11-01

    During seed imbibition at supra-optimal temperature, an increase in the abscisic acid (ABA)/gibberellin (GA) ratio imposes secondary dormancy to prevent germination (thermoinhibition). FUSCA3 (FUS3), a positive regulator of seed dormancy, accumulates in seeds imbibed at high temperature and increases ABA levels to inhibit germination. Recently, we showed that ABA inhibits FUS3 degradation at high temperature, and that ABA and high temperature also inhibit the ubiquitin-proteasome system, by dampening both proteasome activity and protein polyubiquitination. Here, we investigated the role of ABA signaling components and the ABA antagonizing hormone, GA, in the regulation of FUS3 levels. We show that the ABA receptor mutant, pyl1-1, is less sensitive to ABA and thermoinhibition. In this mutant background, FUS3 degradation in vitro is faster. Similarly, GA alleviates thermoinhibition and also increases FUS3 degradation. These results indicate that inhibition of FUS3 degradation at high temperature is dependent on a high ABA/GA ratio and a functional ABA signaling pathway. Thus, FUS3 constitutes an important node in ABA-GA crosstalk during germination at supra-optimal temperature.

  20. Overexpression of the phosphatidylinositol synthase gene (ZmPIS) conferring drought stress tolerance by altering membrane lipid composition and increasing ABA synthesis in maize.

    PubMed

    Liu, Xiuxia; Zhai, Shumei; Zhao, Yajie; Sun, Baocheng; Liu, Cheng; Yang, Aifang; Zhang, Juren

    2013-05-01

    Phosphatidylinositol (PtdIns) synthase is a key enzyme in the phospholipid pathway and catalyses the formation of PtdIns. PtdIns is not only a structural component of cell membranes, but also the precursor of the phospholipid signal molecules that regulate plant response to environment stresses. Here, we obtained transgenic maize constitutively overexpressing or underexpressing PIS from maize (ZmPIS) under the control of a maize ubiquitin promoter. Transgenic plants were confirmed by PCR, Southern blotting analysis and real-time RT-PCR assay. The electrospray ionization tandem mass spectrometry (ESI-MS/MS)-based lipid profiling analysis showed that, under drought stress conditions, the overexpression of ZmPIS in maize resulted in significantly elevated levels of most phospholipids and galactolipids in leaves compared with those in wild type (WT). At the same time, the expression of some genes involved in the phospholipid metabolism pathway and the abscisic acid (ABA) biosynthesis pathway including ZmPLC, ZmPLD, ZmDGK1, ZmDGK3, ZmPIP5K9, ZmABA1, ZmNCED, ZmAAO1, ZmAAO2 and ZmSCA1 was markedly up-regulated in the overexpression lines after drought stress. Consistent with these results, the drought stress tolerance of the ZmPIS sense transgenic plants was enhanced significantly at the pre-flowering stages compared with WT maize plants. These results imply that ZmPIS regulates the plant response to drought stress through altering membrane lipid composition and increasing ABA synthesis in maize.

  1. Drought-Induced Increases in Abscisic Acid Levels in the Root Apex of Sunflower 1

    PubMed Central

    Robertson, J. Mason; Pharis, Richard P.; Huang, Yan Y.; Reid, David M.; Yeung, Edward C.

    1985-01-01

    Abscisic acid (ABA) levels in 3-mm apical root segments of slowly droughted sunflower plants (Helianthus annuus L. cv Russian Giant) were analyzed as the methyl ester by selected ion monitoring gas chromatography-mass spectrometry using characteristic ions. An internal standard, hexadeuterated ABA (d6ABA) was used for quantitative analysis. Sunflower seedlings, grown in aeroponic chambers, were slowly droughted over a 7-day period. Drought stress increased ABA levels in the root tips at 24, 72, and 168 hour sample times. Control plants had 57 to 106 nanograms per gram ABA dry weight in the root tips (leaf water potential, −0.35 to −0.42 megapascals). The greatest increase in ABA, about 20-fold, was found after 72 hours of drought (leaf water potential, −1.34 to −1.47 megapascals). Levels of ABA also increased (about 7− to 54-fold) in 3-mm apical root segments which were excised and then allowed to dessicate for 1 hour at room temperature. PMID:16664535

  2. Overexpression of Rosa rugosa anthocyanidin reductase enhances tobacco tolerance to abiotic stress through increased ROS scavenging and modulation of ABA signaling.

    PubMed

    Luo, Ping; Shen, Yuxiao; Jin, Shuangxia; Huang, Shasha; Cheng, Xu; Wang, Zhen; Li, Penghui; Zhao, Jian; Bao, Manzhu; Ning, Guogui

    2016-04-01

    Anthocyanidin reductase (ANR) is a key enzyme involved in the biosynthesis of proanthocyanidins (PAs) and plays a role in the plant stress response. However, the mechanism by which ANR confers stress tolerance in plants is not understood. Here, we report the isolation of RrANR, the homologous gene from rose, and NtABF, an ABA-response related transcription factor gene from tobacco. These genes were characterized regarding their functions in stress responses through the use of transgenic, transcriptomic and physiological analyses. Over-expression of RrANR in tobacco resulted in an increased accumulation of both PAs and abscisic acid (ABA), and also enhanced stress tolerance. Transcriptomic analysis of these transgenic tobacco lines indicated that RrANR overexpression induced global transcriptomic changes, including these involved in oxidation/reduction, hormone response and secondary metabolism. Genes related to ABA biosynthesis and reactive oxygen species (ROS)-scavenging were up-regulated in RrANR transgenic lines, and these effects were phenocopied by the direct treatment of tobacco plants with PAs and ABA. Transcriptomic data from each of these treatments identified the upregulation of a putative NtABF. Furthermore, the up-regulation of NtABF in RrANR transformants or in PAs- and ABA-treated tobacco plants was associated with enhanced stress tolerance. Overexpression of NtABF in transgenic tobacco mimicked the effects of RrANR-transgenic plants with regard to the up-regulation of ROS-scavenging genes and an increase in oxidative tolerance. Taken together, our findings indicate that overexpression of RrANR results in an increase in plant tolerance to oxidative stress via increased scavenging of ROS and modulation of the ABA signaling pathway.

  3. Improved cold tolerance in Elymus nutans by exogenous application of melatonin may involve ABA-dependent and ABA-independent pathways

    PubMed Central

    Fu, Juanjuan; Wu, Ye; Miao, Yanjun; Xu, Yamei; Zhao, Enhua; Wang, Jin; Sun, Huaien; Liu, Qian; Xue, Yongwei; Xu, Yuefei; Hu, Tianming

    2017-01-01

    Melatonin is an important secondary messenger that plays a central role in plant growth, as well as abiotic and biotic stress tolerance. However, the underlying physiological and molecular mechanisms of melatonin-mediated cold tolerance, especially interactions between melatonin and other key molecules in the plant stress response, remain unknown. Here, the interrelation between melatonin and abscisic acid (ABA) was investigated in two genotypes of Elymus nutans Griseb., the cold-tolerant Damxung (DX) and the cold-sensitive Gannan (GN) under cold stress. Pre-treatment with exogenous melatonin or ABA alleviated oxidative injury via scavenging ROS, while enhancing both antioxidant enzyme activities and non-enzymatic antioxidant contents. Treatment of fluridone, an ABA biosynthesis inhibitor caused membrane lipid peroxidation and lowered melatonin-induced antioxidant defense responses. It is worth noting that cold stress significantly induced both endogenous melatonin and ABA levels in both genotypes. Application of melatonin increased ABA production, while fluridone significantly suppressed melatonin-induced ABA accumulation. ABA and fluridone pre-treatments failed to affect the endogenous melatonin concentration. Moreover, exogenous melatonin up-regulated the expression of cold-responsive genes in an ABA-independent manner. These results indicate that both ABA-dependent and ABA-independent pathways may contribute to melatonin-induced cold tolerance in E. nutans. PMID:28045095

  4. Acquisition of Tn6018-3' CS regions increases colistin MICs against Acinetobacter baumannii isolates harboring new variants of AbaRs.

    PubMed

    Savari, Mohammad; Ekrami, Alireza; Shoja, Saeed; Bahador, Abbas

    2017-02-25

    Colistin is the last hope to treat extensively drug resistance (XDR) Acinetobacter baumannii (A. baumannii) infections, but resistance to colistin is currently reported in clinical centers all over the world. Here, we studied two colistin-resistant A. baumannii isolates with a difference in minimum inhibitory concentrations (MICs) that were isolated from a single burn patient during treatment in the hospitalization period. The international clonal (IC) lineage, multilocus sequence typing (MLST), and multiple loci variable number tandem repeat (VNTR) analysis (MLVA) typing were used to characterize the relatedness of A. baumannii isolates. Lipopolysaccharides (LPS) and PmrAB system analysis by PCR sequencing, polyacrylamide gel electrophoresis (PAGE), and real-time PCR were performed to determine the intactness and probable modifications of the LPS as the main resistance mechanisms to colistin. A combination of PCR, sequencing, and restriction fragment length polymorphism (RFLP) was used for A. baumannii resistance islands (AbaR) mapping as resistance-determinant reservoirs. Two isolates were identical at all MLST and VNTR marker loci that indicated the isolates were the same strain. In comparison to colistin-heteroresistant A. baumannii strain TEH267 (MIC = 1.5 mg/L), colistin-resistant A. baumannii strain TEH273 (MIC ≥256 mg/L) acquired two genomic regions including Tn6018-topA sequence and topA sequence-3' CS in its AbaR structure containing ispA and cadA genes which, it would appear, could be associated with eightfold increase in colistin MIC. Both isolates had new variants of AbaR-like structures which could be derivatives of the typical AbaR3. According to the results of this study, AbaRs could be associated with an increase in MIC to colistin.

  5. Increasing abscisic acid levels by immunomodulation in barley grains induces precocious maturation without changing grain composition.

    PubMed

    Staroske, Nicole; Conrad, Udo; Kumlehn, Jochen; Hensel, Götz; Radchuk, Ruslana; Erban, Alexander; Kopka, Joachim; Weschke, Winfriede; Weber, Hans

    2016-04-01

    Abscisic acid (ABA) accumulates in seeds during the transition to the seed filling phase. ABA triggers seed maturation, storage activity, and stress signalling and tolerance. Immunomodulation was used to alter the ABA status in barley grains, with the resulting transgenic caryopses responding to the anti-ABA antibody gene expression with increased accumulation of ABA. Calculation of free versus antibody-bound ABA reveals large excess of free ABA, increasing signficantly in caryopses from 10 days after fertilization. Metabolite and transcript profiling in anti-ABA grains expose triggered and enhanced ABA-functions such as transcriptional up-regulation of sucrose-to-starch metabolism, storage protein synthesis and ABA-related signal transduction. Thus, enhanced ABA during transition phases induces precocious maturation but negatively interferes with growth and development. Anti-ABA grains display broad constitutive gene induction related to biotic and abiotic stresses. Most of these genes are ABA- and/or stress-inducible, including alcohol and aldehyde dehydrogenases, peroxidases, chaperones, glutathione-S-transferase, drought- and salt-inducible proteins. Conclusively, ABA immunomodulation results in precocious ABA accumulation that generates an integrated response of stress and maturation. Repression of ABA signalling, occurring in anti-ABA grains, potentially antagonizes effects caused by overshooting production. Finally, mature grain weight and composition are unchanged in anti-ABA plants, although germination is somewhat delayed. This indicates that anti-ABA caryopses induce specific mechanisms to desensitize ABA signalling efficiently, which finally yields mature grains with nearly unchanged dry weight and composition. Such compensation implicates the enormous physiological and metabolic flexibilities of barley grains to adjust effects of unnaturally high ABA amounts in order to ensure and maintain proper grain development.

  6. Is the ABA concentration in the sap collected by pressurizing leaves relevant for analysing drought effects on stomata? Evidence from ABA-fed leaves of transgenic plants with modified capacities to synthesize ABA.

    PubMed

    Borel, Charlotte; Simonneau, Thierry

    2002-02-01

    Most studies on the role of ABA in the stomatal response of the whole plant to drought rely on a good estimate of ABA concentration in xylem sap. In this report, varying volumes of sap (V(sap)) were collected by pressurizing leaves cut from several lines of N. plumbaginifolia with modified capacities to synthesize ABA. Leaves were fed with solutions of known ABA concentration ([ABA](solution) from 0-500 micromol m(-3)) for 2-3 h before sap collection. ABA concentration in extruded sap ([ABA](sap)) was compared with [ABA](solution). In low-volume extracts (less than 0.35 mm(3) cm(-2) leaf area) collected from leaves of well-watered plants, [ABA](sap) was close to [ABA](solution). For all lines, [ABA](sap) decreased with increasing V(sap). The same dilution effect was observed for leaves pressurized just after sampling on droughted plants, suggesting, as for detached leaves fed with ABA, that [ABA](sap) in low-volume extracts approximated well with the concentration of ABA entering leaves still attached on droughted plants. However, ABA-fed leaves sampled from droughted plants yielded higher [ABA](sap) than ABA-fed leaves sampled from well-watered plants. [ABA](sap) was also increased, although very slightly, when leaves were preincubated in highly enriched ABA solution. This indicates that some leaf ABA contributed to the ABA concentration returned in the extruded sap. Consistently, [ABA](sap) in medium-volume extracts (0.35-0.65 mm(3) cm(-2) leaf area) was lower for leaves sampled on under-producing lines than on the wild type. Despite these distortions between [ABA](solution) and [ABA](sap) in medium-volume extracts, stomatal conductance of ABA-fed leaves closely correlated with [ABA](sap) with a similar relationship in all cases, whilst relationships with [ABA](solution) were more scattered.

  7. The site of water stress governs the pattern of ABA synthesis and transport in peanut

    PubMed Central

    Hu, Bo; Cao, Jiajia; Ge, Kui; Li, Ling

    2016-01-01

    Abscisic acid (ABA) is one of the most important phytohormones involved in stress responses in plants. However, knowledge of the effect on ABA distribution and transport of water stress at different sites on the plant is limited. In this study, water stress imposed on peanut leaves or roots by treatment with PEG 6000 is termed “leaf stress” or “root stress”, respectively. Immunoenzyme localization technolony was first used to detect ABA distribution in peanut. Under root stress, ABA biosynthesis and distribution level were all more pronounced in root than in leaf. However, ABA transport and the ability to induce stomatal closure were still better in leaf than in root during root stress; However, ABA biosynthesis initially increased in leaf, then rapidly accumulated in the vascular cambium of leaves and induced stomatal closure under leaf stress; ABA produced in root tissues was also transported to leaf tissues to maintain stomatal closure. The vascular system was involved in the coordination and integration of this complex regulatory mechanism for ABA signal accumulation. Water stress subject to root or leaf results in different of ABA biosynthesis and transport ability that trigger stoma close in peanut. PMID:27694957

  8. ABA accumulation in water-stressed Citrus roots does not rely on carotenoid content in this organ.

    PubMed

    Manzi, Matías; Lado, Joanna; Rodrigo, María Jesús; Arbona, Vicent; Gómez-Cadenas, Aurelio

    2016-11-01

    Sustained abscisic acid (ABA) accumulation in dehydrated citrus roots depends on the transport from aerial organs. Under this condition, the role of the β,β-carotenoids (ABA precursors) to the de novo synthesis of ABA in roots needs to be clarified since their low availability in this organ restricts its accumulation. To accomplish that, detached citrus roots were exposed to light (to increase their carotenoid content) and subsequently dehydrated (to trigger ABA accumulation). Stress imposition sharply decreased the pool of β,β-carotenoids but, unexpectedly, no concomitant rise in ABA content was observed. Contrastingly, roots of intact plants (with low levels of carotenoids) showed a similar decrease of ABA precursor together with a significant ABA accumulation. Furthermore, upon dehydration both types of roots showed similar upregulation of the key genes involved in biosynthesis of carotenoids and ABA (CsPSY3a; CsβCHX1; CsβCHX2; CsNCED1; CsNCED2), demonstrating a conserved transcriptional response triggered by water stress. Thus, the sharp decrease in root carotenoid levels in response to dehydration should be related to other stress-related signals instead of contributing to ABA biosynthesis. In summary, ABA accumulation in dehydrated-citrus roots largely relies on the presence of the aerial organs and it is independent of the amount of available root β,β-carotenoids.

  9. Linking Turgor with ABA Biosynthesis: Implications for Stomatal Responses to Vapor Pressure Deficit across Land Plants.

    PubMed

    McAdam, Scott A M; Brodribb, Timothy J

    2016-07-01

    Stomatal responses to changes in vapor pressure deficit (VPD) constitute the predominant form of daytime gas-exchange regulation in plants. Stomatal closure in response to increased VPD is driven by the rapid up-regulation of foliar abscisic acid (ABA) biosynthesis and ABA levels in angiosperms; however, very little is known about the physiological trigger for this increase in ABA biosynthesis at increased VPD Using a novel method of modifying leaf cell turgor by the application of external pressures, we test whether changes in turgor pressure can trigger increases in foliar ABA levels over 20 min, a period of time most relevant to the stomatal response to VPD We found in angiosperm species that the biosynthesis of ABA was triggered by reductions in leaf turgor, and in two species tested, that a higher sensitivity of ABA synthesis to leaf turgor corresponded with a higher stomatal sensitivity to VPD In contrast, representative species from nonflowering plant lineages did not show a rapid turgor-triggered increase in foliar ABA levels, which is consistent with previous studies demonstrating passive stomatal responses to changes in VPD in these lineages. Our method provides a new tool for characterizing the response of stomata to water availability.

  10. Personality Traits Associated with Occupational "Burnout" in ABA Therapists

    ERIC Educational Resources Information Center

    Hurt, Amy A.; Grist, Cathy Lann; Malesky, Lann A., Jr.; McCord, David M.

    2013-01-01

    Background: Applied behaviour analysis (ABA) therapists typically work one-to-one with children with autism for extended periods of time, which often leads to high levels of job-related stress, lower levels of job satisfaction, increased frequency of occupational "burnout" and higher than average job turnover (Journal of Autism…

  11. ABA-mediated transcriptional regulation in response to osmotic stress in plants.

    PubMed

    Fujita, Yasunari; Fujita, Miki; Shinozaki, Kazuo; Yamaguchi-Shinozaki, Kazuko

    2011-07-01

    The plant hormone abscisic acid (ABA) plays a pivotal role in a variety of developmental processes and adaptive stress responses to environmental stimuli in plants. Cellular dehydration during the seed maturation and vegetative growth stages induces an increase in endogenous ABA levels, which control many dehydration-responsive genes. In Arabidopsis plants, ABA regulates nearly 10% of the protein-coding genes, a much higher percentage than other plant hormones. Expression of the genes is mainly regulated by two different families of bZIP transcription factors (TFs), ABI5 in the seeds and AREB/ABFs in the vegetative stage, in an ABA-responsive-element (ABRE) dependent manner. The SnRK2-AREB/ABF pathway governs the majority of ABA-mediated ABRE-dependent gene expression in response to osmotic stress during the vegetative stage. In addition to osmotic stress, the circadian clock and light conditions also appear to participate in the regulation of ABA-mediated gene expression, likely conferring versatile tolerance and repressing growth under stress conditions. Moreover, various other TFs belonging to several classes, including AP2/ERF, MYB, NAC, and HD-ZF, have been reported to engage in ABA-mediated gene expression. This review mainly focuses on the transcriptional regulation of ABA-mediated gene expression in response to osmotic stress during the vegetative growth stage in Arabidopsis.

  12. The Arabidopsis transcription factor ABIG1 relays ABA signaled growth inhibition and drought induced senescence

    PubMed Central

    Liu, Tie; Longhurst, Adam D; Talavera-Rauh, Franklin; Hokin, Samuel A; Barton, M Kathryn

    2016-01-01

    Drought inhibits plant growth and can also induce premature senescence. Here we identify a transcription factor, ABA INSENSITIVE GROWTH 1 (ABIG1) required for abscisic acid (ABA) mediated growth inhibition, but not for stomatal closure. ABIG1 mRNA levels are increased both in response to drought and in response to ABA treatment. When treated with ABA, abig1 mutants remain greener and produce more leaves than comparable wild-type plants. When challenged with drought, abig1 mutants have fewer yellow, senesced leaves than wild-type. Induction of ABIG1 transcription mimics ABA treatment and regulates a set of genes implicated in stress responses. We propose a model in which drought acts through ABA to increase ABIG1 transcription which in turn restricts new shoot growth and promotes leaf senescence. The results have implications for plant breeding: the existence of a mutant that is both ABA resistant and drought resistant points to new strategies for isolating drought resistant genetic varieties. DOI: http://dx.doi.org/10.7554/eLife.13768.001 PMID:27697148

  13. Accumulation of the hormone abscisic acid (ABA) at the infection site of the fungus Cercospora beticola supports the role of ABA as a repressor of plant defence in sugar beet.

    PubMed

    Schmidt, Klaus; Pflugmacher, Maike; Klages, Simone; Mäser, Anja; Mock, Andrea; Stahl, Dietmar J

    2008-09-01

    Inducible plant defence responses in sugar beet (Beta vulgaris L.) leaves are repressed during the early phase of infection by the fungus Cercospora beticola. In this report, we show that the concentration of the plant hormone abscisic acid (ABA) increases in sugar beet leaves during C. beticola infection. After an initial burst of ABA induced by inoculation of the fungus, elevated ABA concentrations were detected during the fungal penetration and colonization phases 3-9 days after inoculation. Fifteen days after inoculation, with visible onset of the necrotic phase of infection, the strongly elevated ABA concentrations in infected leaves were at levels similar to drought-stressed plants. A synthetic promoter composed of four copies of the ABA-responsive element (ABRE) A2 and the coupling element CE3 of the ABA-inducible barley gene HVA1 was strongly induced by ABA and C. beticola infection in transgenic sugar beet leaves. Analysis of the spatial pattern of promoter activity revealed that the ABA-inducible promoter was locally activated at the fungal infection sites. Furthermore, expression of the basic leucine zipper transcription factor AREB1 was induced by drought stress and fungal infection in the sugar beet. Application of ABA reduced the promoter activity of the phenylalanine ammonia lyase (BvPAL) gene, and this effect was observed with the -34 to +248 BvPAL promoter region. This region is equivalent to the core promoter, which is necessary for the suppression of BvPAL expression by C. beticola, as recently shown. These data indicate that ABA accumulation and activation of the ABA-dependent signalling cascade are the primary cause of suppression of BvPAL expression during infection of sugar beet leaves.

  14. Nitric oxide modulates sensitivity to ABA

    PubMed Central

    Lozano-Juste, Jorge

    2010-01-01

    Nitric oxide (NO) is a gas with crucial signaling functions in plant defense and development. As demonstrated by generating a triple nia1nia2noa1-2 mutant with extremely low levels of NO (February 2010 issue of Plant Physiology), NO is synthesized in plants through mainly two different pathways involving nitrate reductase (NR/NIA) and NO Associated 1 (AtNOA1) proteins. Depletion of basal NO levels leads to a priming of ABA-triggered responses that causes hypersensitivity to this hormone and results in enhanced seed dormancy and decreased seed germination and seedling establishment in the triple mutant. NO produced under non-stressed conditions represses inhibition of seed developmental transitions by ABA. Moreover, NO plays a positive role in post-germinative vegetative development and also exerts a critical control of ABA-related functions on stomata closure. The triple nia1nia2noa1-2 mutant is hypersensitive to ABA in stomatal closure thus resulting in a extreme phenotype of resistance to drought. In the light of the recent discovery of PYR/PYL/RCAR as a family of potential ABA receptors, regulation of ABA sensitivity by NO may be exerted either directly on ABA receptors or on downstream signalling components; both two aspects that deserve our present and future attention. PMID:20168082

  15. Linking Turgor with ABA Biosynthesis: Implications for Stomatal Responses to Vapor Pressure Deficit across Land Plants1[OPEN

    PubMed Central

    McAdam, Scott A.M.; Brodribb, Timothy J.

    2016-01-01

    Stomatal responses to changes in vapor pressure deficit (VPD) constitute the predominant form of daytime gas-exchange regulation in plants. Stomatal closure in response to increased VPD is driven by the rapid up-regulation of foliar abscisic acid (ABA) biosynthesis and ABA levels in angiosperms; however, very little is known about the physiological trigger for this increase in ABA biosynthesis at increased VPD. Using a novel method of modifying leaf cell turgor by the application of external pressures, we test whether changes in turgor pressure can trigger increases in foliar ABA levels over 20 min, a period of time most relevant to the stomatal response to VPD. We found in angiosperm species that the biosynthesis of ABA was triggered by reductions in leaf turgor, and in two species tested, that a higher sensitivity of ABA synthesis to leaf turgor corresponded with a higher stomatal sensitivity to VPD. In contrast, representative species from nonflowering plant lineages did not show a rapid turgor-triggered increase in foliar ABA levels, which is consistent with previous studies demonstrating passive stomatal responses to changes in VPD in these lineages. Our method provides a new tool for characterizing the response of stomata to water availability. PMID:27208264

  16. Molecular cloning and characterization of the ABA-specific glucosyltransferase gene from bean (Phaseolus vulgaris L.).

    PubMed

    Palaniyandi, Sasikumar Arunachalam; Chung, Gyuhwa; Kim, Sang Hyon; Yang, Seung Hwan

    2015-04-15

    Levels of the plant hormone abscisic acid (ABA) are maintained in homeostasis by a balance of its biosynthesis, catabolism and conjugation. The detailed molecular and signaling events leading to strict homeostasis are not completely understood in crop plants. In this study, we obtained cDNA of an ABA-inducible, ABA-specific UDP-glucosyltransferase (ABAGT) from the bean plant (Phaseolus vulgaris L.) involved in conjugation of a glucose residue to ABA to form inactive ABA-glucose ester (ABA-GE) to examine its role during development and abiotic stress in bean. The bacterially expressed PvABAGTase enzyme showed ABA-specific glucosylation activity in vitro. A higher level of the PvABAGT transcript was observed in mature leaves, mature flowers, roots, seed coats and embryos as well as upon rehydration following a period of dehydration. Overexpression of 35S::PvABAGT in Arabidopsis showed reduced sensitivity to ABA compared with WT. The transgenic plants showed a high level of ABA-GE without significant decrease in the level of ABA compared with the wild type (WT) during dehydration stress. Upon rehydration, the levels of ABA and phaseic acid (PA) decreased in the WT and the PvABAGT-overexpressing lines with high levels of ABA-GE only in the transgenic plants. Our findings suggest that the PvABAGT gene could play a role in ABA homeostasis during development and stress responses in bean and its overexpression in Arabidopsis did not alter ABA homeostasis during dehydration stress.

  17. The Heat Stress Factor HSFA6b Connects ABA Signaling and ABA-Mediated Heat Responses1[OPEN

    PubMed Central

    Yang, Chen-Ru

    2016-01-01

    Heat stress response (HSR) is a conserved mechanism developed to increase the expression of heat shock proteins (HSPs) via a heat shock factor (HSF)-dependent mechanism. Signaling by the stress phytohormone abscisic acid (ABA) is involved in acquired thermotolerance as well. Analysis of Arabidopsis (Arabidopsis thaliana) microarray databases revealed that the expression of HSFA6b, a class A HSF, extensively increased with salinity, osmotic, and cold stresses, but not heat. Here, we show that HSFA6b plays a pivotal role in the response to ABA and in thermotolerance. Salt-inducible HSFA6b expression was down-regulated in ABA-insensitive and -deficient mutants; however, exogenous ABA application restored expression in ABA-deficient, but not -insensitive plants. Thus, ABA signaling is required for proper HSFA6b expression. A transcriptional activation assay of protoplasts revealed that ABA treatment and coexpression of an ABA signaling master effector, ABA-RESPONSIVE ELEMENT-BINDING PROTEIN1, could activate the HSFA6b promoter. In addition, HSFA6b directly bound to the promoter of DEHYDRATION-RESPONSIVE ELEMENT-BINDING PROTEIN2A and enhanced its expression. Analysis of ABA responses in seed germination, cotyledon greening, and root growth as well as salt and drought tolerance in HSFA6b-null, overexpression, and dominant negative mutants revealed that HSFA6b is a positive regulator participating in ABA-mediated salt and drought resistance. Thermoprotection tests showed that HSFA6b was required for thermotolerance acquisition. Our study reveals a network in which HSFA6b operates as a downstream regulator of the ABA-mediated stress response and is required for heat stress resistance. This new ABA-signaling pathway is integrated into the complex HSR network in planta. PMID:27493213

  18. Abscisic acid metabolizing rhizobacteria decrease ABA concentrations in planta and alter plant growth.

    PubMed

    Belimov, Andrey A; Dodd, Ian C; Safronova, Vera I; Dumova, Valentina A; Shaposhnikov, Alexander I; Ladatko, Alexander G; Davies, William J

    2014-01-01

    Although endogenous phytohormones such as abscisic acid (ABA) regulate root growth, and many rhizobacteria can modulate root phytohormone status, hitherto there have been no reports of rhizobacteria mediating root ABA concentrations and growth by metabolising ABA. Using a selective ABA-supplemented medium, two bacterial strains were isolated from the rhizosphere of rice (Oryza sativa) seedlings grown in sod-podzolic soil and assigned to Rhodococcus sp. P1Y and Novosphingobium sp. P6W using partial 16S rRNA gene sequencing and phenotypic patterns by the GEN III MicroPlate test. Although strain P6W had more rapid growth in ABA-supplemented media than strain P1Y, both could utilize ABA as a sole carbon source in batch culture. When rice seeds were germinated on filter paper in association with bacteria, root ABA concentration was not affected, but shoot ABA concentration of inoculated plants decreased by 14% (strain P6W) and 22% (strain P1Y). When tomato (Solanum lycopersicum) genotypes differing in ABA biosynthesis (ABA deficient mutants flacca - flc, and notabilis - not and the wild-type cv. Ailsa Craig, WT) were grown in gnotobiotic cultures on nutrient solution agar, rhizobacterial inoculation decreased root and/or leaf ABA concentrations, depending on plant and bacteria genotypes. Strain P6W inhibited primary root elongation of all genotypes, but increased leaf biomass of WT plants. In WT plants treated with silver ions that inhibit ethylene perception, both ABA-metabolising strains significantly decreased root ABA concentration, and strain P6W decreased leaf ABA concentration. Since these changes in ABA status also occurred in plants that were not treated with silver, it suggests that ethylene was probably not involved in regulating bacteria-mediated changes in ABA concentration. Correlations between plant growth and ABA concentrations in planta suggest that ABA-metabolising rhizobacteria may stimulate growth via an ABA-dependent mechanism.

  19. ABA flow modelling in Ricinus communis exposed to salt stress and variable nutrition

    PubMed Central

    Peuke, Andreas D.

    2016-01-01

    In a series of experiments with Ricinus communis, abscisic acid (ABA) concentrations in tissues and transport saps, its de novo biosynthesis, long-distance transport, and metabolism (degradation) were affected by nutritional conditions, nitrogen (N) source, and nutrient limitation, or salt stress. In the present study these data were statistically re-evaluated, and new correlations presented that underpin the importance of this universal phytohormone. The biggest differences in ABA concentration were observed in xylem sap. N source had the strongest effect; however, nutrient limitation (particularly phosphorus limitation) and salt also had significant effects. ABA was found in greater concentration in phloem sap compared with xylem sap; however, the effect of treatment on ABA concentration in phloem was lower. In the leaves, ABA concentration was most variable compared with the other tissues. This variation was only affected by the N source. In roots, ABA was significantly decreased by nutrient limitation. Of the compartments in which ABA was quantified, xylem sap ABA concentration was most significantly correlated with leaf stomatal conductance and leaf growth. Additionally, ABA concentration in xylem was significantly correlated to that in phloem, indicating a 6-fold concentration increase from xylem to phloem. The ABA flow model showed that biosynthesis of ABA in roots affected the xylem flow of ABA. Moreover, ABA concentration in xylem affected the degradation of the phytohormone in shoots and also its export from shoots via phloem. The role of phloem transport is discussed since it stimulates ABA metabolism in roots. PMID:27440939

  20. Carbon dioxide enrichment alleviates heat stress by improving cellular redox homeostasis through an ABA-independent process in tomato plants.

    PubMed

    Li, X; Ahammed, G J; Zhang, Y Q; Zhang, G Q; Sun, Z H; Zhou, J; Zhou, Y H; Xia, X J; Yu, J Q; Shi, K

    2015-01-01

    Plant responses to elevated CO₂ and high temperature are critically regulated through a complex network of phytohormones and redox homeostasis. However, the involvement of abscisic acid (ABA) in plant adaptation to heat stress under elevated CO₂ conditions has not been thoroughly studied. This study investigated the interactive effects of elevated CO₂ (800 μmol·mol(-1) ) and heat stress (42 °C for 24 h) on the endogenous level of ABA and the cellular redox state of two genotypes of tomato with different ABA biosynthesis capacities. Heat stress significantly decreased maximum photochemical efficiency of PSII (Fv/Fm) and leaf water potential, but also increased levels of malondialdehyde (MDA) and electrolyte leakage (EL) in both genotypes. Heat-induced damage was more severe in the ABA-deficient mutant notabilis (not) than in its parental cultivar Ailsa Craig (Ailsa), suggesting that a certain level of endogenous ABA is required to minimise the heat-induced oxidative damage to the photosynthetic apparatus. Irrespective of genotype, the enrichment of CO₂ remarkably stimulated Fv/Fm, MDA and EL in heat-stressed plants towards enhanced tolerance. In addition, elevated CO₂ significantly strengthened the antioxidant capacity of heat-stressed tomato seedlings towards a reduced cellular redox state for a prolonged period, thereby mitigating oxidative stress. However, elevated CO₂ and heat stress did not alter the endogenous level of ABA or the expression of its biosynthetic gene NCED2 in either genotype, indicating that ABA is not involved in elevated CO₂ -induced heat stress alleviation. The results of this study suggest that elevated CO₂ alleviated heat stress through efficient regulation of the cellular redox poise in an ABA-independent manner in tomato plants.

  1. A NAP-AAO3 regulatory module promotes chlorophyll degradation via ABA biosynthesis in Arabidopsis leaves.

    PubMed

    Yang, Jiading; Worley, Eric; Udvardi, Michael

    2014-12-01

    Chlorophyll degradation is an important part of leaf senescence, but the underlying regulatory mechanisms are largely unknown. Excised leaves of an Arabidopsis thaliana NAC-LIKE, ACTIVATED BY AP3/PI (NAP) transcription factor mutant (nap) exhibited lower transcript levels of known chlorophyll degradation genes, STAY-GREEN1 (SGR1), NON-YELLOW COLORING1 (NYC1), PHEOPHYTINASE (PPH), and PHEIDE a OXYGENASE (PaO), and higher chlorophyll retention than the wild type during dark-induced senescence. Transcriptome coexpression analysis revealed that abscisic acid (ABA) metabolism/signaling genes were disproportionately represented among those positively correlated with NAP expression. ABA levels were abnormally low in nap leaves during extended darkness. The ABA biosynthetic genes 9-CIS-EPOXYCAROTENOID DIOXYGENASE2, ABA DEFICIENT3, and ABSCISIC ALDEHYDE OXIDASE3 (AAO3) exhibited abnormally low transcript levels in dark-treated nap leaves. NAP transactivated the promoter of AAO3 in mesophyll cell protoplasts, and electrophoretic mobility shift assays showed that NAP can bind directly to a segment (-196 to -162 relative to the ATG start codon) of the AAO3 promoter. Exogenous application of ABA increased the transcript levels of SGR1, NYC1, PPH, and PaO and suppressed the stay-green phenotype of nap leaves during extended darkness. Overexpression of AAO3 in nap leaves also suppressed the stay-green phenotype under extended darkness. Collectively, the results show that NAP promotes chlorophyll degradation by enhancing transcription of AAO3, which leads to increased levels of the senescence-inducing hormone ABA.

  2. Reduced ABA Accumulation in the Root System is Caused by ABA Exudation in Upland Rice (Oryza sativa L. var. Gaoshan1) and this Enhanced Drought Adaptation.

    PubMed

    Shi, Lu; Guo, Miaomiao; Ye, Nenghui; Liu, Yinggao; Liu, Rui; Xia, Yiji; Cui, Suxia; Zhang, Jianhua

    2015-05-01

    Lowland rice (Nipponbare) and upland rice (Gaoshan 1) that are comparable under normal and moderate drought conditions showed dramatic differences in severe drought conditions, both naturally occurring long-term drought and simulated rapid water deficits. We focused on their root response and found that enhanced tolerance of upland rice to severe drought conditions was mainly due to the lower level of ABA in its roots than in those of the lowland rice. We first excluded the effect of ABA biosynthesis and catabolism on root-accumulated ABA levels in both types of rice by monitoring the expression of four OsNCED genes and two OsABA8ox genes. Next, we excluded the impact of the aerial parts on roots by suppressing leaf-biosynthesized ABA with fluridone and NDGA (nordihydroguaiaretic acid), and measuring the ABA level in detached roots. Instead, we proved that upland rice had the ability to export considerably more root-sourced ABA than lowland rice under severe drought, which improved ABA-dependent drought adaptation. The investigation of apoplastic pH in root cells and root anatomy showed that ABA leakage in the root system of upland rice was related to high apoplastic pH and the absence of Casparian bands in the sclerenchyma layer. Finally, taking some genes as examples, we predicted that different ABA levels in rice roots stimulated distinct ABA perception and signaling cascades, which influenced its response to water stress.

  3. Roles of xanthophylls and exogenous ABA in protection against NaCl-induced photodamage in rice (Oryza sativa L) and cabbage (Brassica campestris).

    PubMed

    Zhu, Su-Qin; Chen, Ming-Wei; Ji, Ben-Hua; Jiao, De-Mao; Liang, Jian-Sheng

    2011-08-01

    Changes in actual efficiency of PS II photochemistry, non-photochemical quenching (NPQ), content of xanthophylls and kinetics of de-epoxidation were studied in ABA-fed and non-ABA-fed leaves of rice and cabbage under NaCl stress. Salt stress induced more progressive decrease in actual efficiency of PS II photochemistry (ФPS II), higher reduction state of PS II, and a small significant increase in NPQ in NaCl-sensitive rice plants as compared with NaCl-tolerant cabbage plants, whereas exogenously supplied ABA alleviated the decrease in actual efficiency of PS II photochemistry (ФPS II), induced a lower reduction state of PS II, and caused higher capacity of NPQ in ABA-fed plants than in non-ABA-fed plants. As a result, there were higher activities of photosynthetic electron transport, higher capacity of energy dissipation, and lower cumulation of excess light in cabbage than in rice plants, and in ABA-fed leaves than in non-ABA-fed leaves. The effect of ABA was more efficient in cabbage than in rice plants. Addition of exogenous ABA resulted in enhancement of the size of the xanthophyll cycle pool, promotion of de-epoxidation of the xanthophyll cycle components, and a rise in the level of NPQ by altering the kinetics of de-epoxidation of the xanthophyll cycle. Protection from photodamage appears to be achieved by coordinated contributions by exogenous ABA and xanthophyll cycle-mediated NPQ. This variety of photoprotective mechanisms may be essential for conferring photodamage tolerance under NaCl stress.

  4. The AvrB_AvrC domain of AvrXccC of Xanthomonas campestris pv. campestris is required to elicit plant defense responses and manipulate ABA homeostasis.

    PubMed

    Ho, Yi-Ping; Tan, Choon Meng; Li, Meng-Ying; Lin, Hong; Deng, Wen-Ling; Yang, Jun-Yi

    2013-04-01

    Plant disease induced by Xanthomonas campestris pv. campestris depends on type III effectors but the molecular basis is poorly understood. Here, AvrXccC8004 was characterized, and it was found that the AvrB_AvrC domain was essential and sufficient to elicit defense responses in an Arabidopsis-resistant ecotype (Col-0). An upregulation of genes in responding to the AvrB_AvrC domain of AvrXccC8004 was shown in a profile of host gene expression. The molecular changes were correlated with morphological changes observed in phenotypic and ultrastructural characterizations. Interestingly, the abscisic acid (ABA)-signaling pathway was also a prominent target for the AvrB_AvrC domain of AvrXccC8004. The highly elicited NCED5, encoding a key enzyme of ABA biosynthesis, was increased in parallel with ABA levels in AvrXccC8004 transgenic plants. Consistently, the X. campestris pv. campestris 8004 ΔavrXccC mutant was severely impaired in the ability to manipulate the accumulation of ABA and induction of ABA-related genes in challenged leaves. Moreover, exogenous application of ABA also enhanced the susceptibility of Arabidopsis to the X. campestris pv. campestris strains. These results indicate that the AvrB_AvrC domain of AvrXccC8004 alone has the activity to manipulate ABA homeostasis, which plays an important role in regulating the interactions of X. campestris pv. campestris and Arabidopsis.

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

    PubMed Central

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

    2015-01-01

    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 0.22cm3 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. PMID:25547916

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

    PubMed

    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.

  7. ABA signaling is necessary but not sufficient for RD29B transcriptional memory during successive dehydration stresses in Arabidopsis thaliana.

    PubMed

    Virlouvet, Laetitia; Ding, Yong; Fujii, Hiroaki; Avramova, Zoya; Fromm, Michael

    2014-07-01

    Plants subjected to a prior dehydration stress were seen to have altered transcriptional responses during a subsequent dehydration stress for up to 5 days after the initial stress. The abscisic acid (ABA) inducible RD29B gene of Arabidopsis thaliana was strongly induced after the first stress and displayed transcriptional memory with transcript levels nine-fold higher during the second dehydration stress. These increased transcript levels were due to an increased rate of transcription and are associated with an altered chromatin template during the recovery interval between the dehydration stresses. Here we use a combination of promoter deletion/substitutions, mutants in the trans-acting transcription factors and their upstream protein kinases, and treatments with exogenous ABA or dehydration stress to advance our understanding of the features required for transcriptional memory of RD29B. ABA Response Elements (ABREs) are sufficient to confer transcriptional memory on a minimal promoter, although there is a context effect from flanking sequences. Different mutations in Snf1 Related Protein Kinase 2 (SnRK2) genes positively and negatively affected the response, suggesting that this effect is important for transcriptional memory. Although exogenous ABA treatments could prime transcriptional memory, a second ABA treatment was not sufficient to activate transcriptional memory. Therefore, we concluded that transcriptional memory requires ABA and an ABA-independent factor that is induced or activated by a subsequent dehydration stress and directly or indirectly results in a more active RD29B chromatin template. These results advance our knowledge of the cis- and trans-acting factors that are required for transcriptional memory of RD29B.

  8. Sulphate as a xylem-borne chemical signal precedes the expression of ABA biosynthetic genes in maize roots.

    PubMed

    Ernst, Laura; Goodger, Jason Q D; Alvarez, Sophie; Marsh, Ellen L; Berla, Bert; Lockhart, Eric; Jung, Jiyul; Li, Pinghua; Bohnert, Hans J; Schachtman, Daniel P

    2010-07-01

    Recent reports suggest that early sensing of soil water stress by plant roots and the concomitant reduction in stomatal conductance may not be mediated by root-sourced abscisic acid (ABA), but that other xylem-borne chemicals may be the primary stress signal(s). To gain more insight into the role of root-sourced ABA, the timing and location of the expression of genes for key enzymes involved in ABA biosynthesis in Zea mays roots was measured and a comprehensive analysis of root xylem sap constituents from the early to the later stages of water stress was conducted. Xylem sap and roots were sampled from plants at an early stage of water stress when only a reduction in leaf conductance was measured, as well as at later stages when leaf xylem pressure potential decreased. It was found that the majority of ABA biosynthetic genes examined were only significantly expressed in the elongation region of roots at a later stage of water stress. Apart from ABA, sulphate was the only xylem-borne chemical that consistently showed significantly higher concentrations from the early to the later stages of stress. Moreover, there was an interactive effect of ABA and sulphate in decreasing maize transpiration rate and Vicia faba stomatal aperture, as compared to ABA alone. The expression of a sulphate transporter gene was also analysed and it was found that it had increased in the elongation region of roots from the early to the later stages of water stress. Our results support the suggestion that in the early stage of water stress, increased levels of ABA in xylem sap may not be due to root biosynthesis, ABA glucose ester catabolism or pH-mediated redistribution, but may be due to shoot biosynthesis and translocation to the roots. The analysis of xylem sap mineral content and bioassays indicate that the anti-transpirant effect of the ABA reaching the stomata at the early stages of water stress may be enhanced by the increased concentrations of sulphate in the xylem which is also

  9. The barley HvNAC6 transcription factor affects ABA accumulation and promotes basal resistance against powdery mildew.

    PubMed

    Chen, Yan-Jun; Perera, Venura; Christiansen, Michael W; Holme, Inger B; Gregersen, Per L; Grant, Murray R; Collinge, David B; Lyngkjær, Michael F

    2013-12-01

    Barley HvNAC6 is a member of the plant-specific NAC (NAM, ATAF1,2, CUC2) transcription factor family and we have shown previously that it acts as a positive regulator of basal resistance in barley against the biotrophic pathogen Blumeria graminis f. sp. hordei (Bgh). In this study, we use a transgenic approach to constitutively silence HvNAC6 expression, using RNA interference (RNAi), to investigate the in vivo functions of HvNAC6 in basal resistance responses in barley in relation to the phytohormone ABA. The HvNAC6 RNAi plants displayed reduced HvNAC6 transcript levels and were more susceptible to Bgh than wild-type plants. Application of exogenous ABA increased basal resistance against Bgh in wild-type plants, but not in HvNAC6 RNAi plants, suggesting that ABA is a positive regulator of basal resistance which depends on HvNAC6. Silencing of HvNAC6 expression altered the light/dark rhythm of ABA levels which were, however, not influenced by Bgh inoculation. The expression of the two ABA biosynthetic genes HvNCED1 and HvNCED2 was compromised, and transcript levels of the ABA conjugating HvBG7 enzyme were elevated in the HvNAC6 RNAi lines, but this effect was not clearly associated with transgene-mediated resistance. Together, these data support a function of HvNAC6 as a regulator of ABA-mediated defence responses for maintenance of effective basal resistance against Bgh.

  10. [ABA accumulation and distribution during the leaf tissues shows its role stomatal conductance regulation under short-term salinity].

    PubMed

    Akhiiarova, G R; Fricke, W; Veselov, D S; Kudoiarova, G R; Veselov, S Iu

    2006-01-01

    The regulative role of ABA in the rapid plant stomatal reactions in response to salinity was investigated. The influence of the short-term salinity on the overall ABA accumulation and its distribution within the mature leaf (revealed by immunohystochemical technique) and stomatal conductance of barley (Hordeum vulgare L.) were determined. Rapid bulk leaf ABA accumulation and increase in ABA immunolabeling in the mesophyl and guard cells of stomata were shown. The bulk ABA increasing in mature barley leaves coincided with stomatal closure induced by salt treatment indicating on the ABA contribution to the rapid stomatal closure.

  11. ABA receptor PYL9 promotes drought resistance and leaf senescence.

    PubMed

    Zhao, Yang; Chan, Zhulong; Gao, Jinghui; Xing, Lu; Cao, Minjie; Yu, Chunmei; Hu, Yuanlei; You, Jun; Shi, Haitao; Zhu, Yingfang; Gong, Yuehua; Mu, Zixin; Wang, Haiqing; Deng, Xin; Wang, Pengcheng; Bressan, Ray A; Zhu, Jian-Kang

    2016-02-16

    Drought stress is an important environmental factor limiting plant productivity. In this study, we screened drought-resistant transgenic plants from 65 promoter-pyrabactin resistance 1-like (PYL) abscisic acid (ABA) receptor gene combinations and discovered that pRD29A::PYL9 transgenic lines showed dramatically increased drought resistance and drought-induced leaf senescence in both Arabidopsis and rice. Previous studies suggested that ABA promotes senescence by causing ethylene production. However, we found that ABA promotes leaf senescence in an ethylene-independent manner by activating sucrose nonfermenting 1-related protein kinase 2s (SnRK2s), which subsequently phosphorylate ABA-responsive element-binding factors (ABFs) and Related to ABA-Insensitive 3/VP1 (RAV1) transcription factors. The phosphorylated ABFs and RAV1 up-regulate the expression of senescence-associated genes, partly by up-regulating the expression of Oresara 1. The pyl9 and ABA-insensitive 1-1 single mutants, pyl8-1pyl9 double mutant, and snrk2.2/3/6 triple mutant showed reduced ABA-induced leaf senescence relative to the WT, whereas pRD29A::PYL9 transgenic plants showed enhanced ABA-induced leaf senescence. We found that leaf senescence may benefit drought resistance by helping to generate an osmotic potential gradient, which is increased in pRD29A::PYL9 transgenic plants and causes water to preferentially flow to developing tissues. Our results uncover the molecular mechanism of ABA-induced leaf senescence and suggest an important role of PYL9 and leaf senescence in promoting resistance to extreme drought stress.

  12. Anti-transpirant activity in xylem sap from flooded tomato (Lycopersicon esculentum Mill.) plants is not due to pH-mediated redistributions of root- or shoot-sourced ABA.

    PubMed

    Else, Mark A; Taylor, June M; Atkinson, Christopher J

    2006-01-01

    In flooded soils, the rapid effects of decreasing oxygen availability on root metabolic activity are likely to generate many potential chemical signals that may impact on stomatal apertures. Detached leaf transpiration tests showed that filtered xylem sap, collected at realistic flow rates from plants flooded for 2 h and 4 h, contained one or more factors that reduced stomatal apertures. The closure could not be attributed to increased root output of the glucose ester of abscisic acid (ABA-GE), since concentrations and deliveries of ABA conjugates were unaffected by soil flooding. Although xylem sap collected from the shoot base of detopped flooded plants became more alkaline within 2 h of flooding, this rapid pH change of 0.5 units did not alter partitioning of root-sourced ABA sufficiently to prompt a transient increase in xylem ABA delivery. More shoot-sourced ABA was detected in the xylem when excised petiole sections were perfused with pH 7 buffer, compared with pH 6 buffer. Sap collected from the fifth oldest leaf of "intact" well-drained plants and plants flooded for 3 h was more alkaline, by approximately 0.4 pH units, than sap collected from the shoot base. Accordingly, xylem [ABA] was increased 2-fold in sap collected from the fifth oldest petiole compared with the shoot base of flooded plants. However, water loss from transpiring, detached leaves was not reduced when the pH of the feeding solution containing 3-h-flooded [ABA] was increased from 6.7 to 7.1 Thus, the extent of the pH-mediated, shoot-sourced ABA redistribution was not sufficient to raise xylem [ABA] to physiologically active levels. Using a detached epidermis bioassay, significant non-ABA anti-transpirant activity was also detected in xylem sap collected at intervals during the first 24 h of soil flooding.

  13. Reduced Accumulation of ABA during Water Stress in a Molybdenum Cofactor Mutant of Barley 1

    PubMed Central

    Walker-Simmons, Mary; Kudrna, David A.; Warner, Robert L.

    1989-01-01

    A barley (Hordeum vulgare L.) mutant (Az34) has been identified with low basal levels of abscisic acid (ABA) and with reduced capacity for producing ABA in response to water stress. The mutation is in a gene controlling the molybdenum cofactor resulting in a pleiotropic deficiency in at least three molybdoenzymes, nitrate reductase, xanthine dehydrogenase, and aldehyde oxidase. The mutant was found to lack aldehyde oxidase activity with several substrates including: (a) ABA aldehyde, a putative precursor of ABA; (b) an acetylenic analog of ABA aldehyde; and (c) heptaldehyde. Elevating the growth temperature from 18 to 26°C caused mutant leaves to wilt and brown. Desiccation of mutant leaves was prevented by applying ABA. These results indicate that ABA biosynthesis at some developmental stages is dependent upon a molybdoenzyme which may be an aldehyde oxidase. Images Figure 5 PMID:16666835

  14. Isohydric and anisohydric strategies of wheat genotypes under osmotic stress: biosynthesis and function of ABA in stress responses.

    PubMed

    Gallé, Ágnes; Csiszár, Jolán; Benyó, Dániel; Laskay, Gábor; Leviczky, Tünde; Erdei, László; Tari, Irma

    2013-11-01

    Changes in water potential (ψw), stomatal conductance, abscisic acid (ABA) accumulation, expression of the major genes involved in ABA biosynthesis, activities of abscisic aldehyde oxidase (AO, EC 1.2.3.1) and antioxidant enzymes were studied in two wheat cultivars with contrasting acclimation strategies subjected to medium strength osmotic stress (-0.976MPa) induced by polyethylene glycol (PEG 6000). Because the biosynthetic pathway of ABA involves multiple gene products, the aim of this study was to unravel how these genes are regulated in isohydric and anisohydric wheat genotypes. In the root tissues of the isohydric cultivar, Triticum aestivum cv. Kobomugi, osmotic stress increased the transcript levels of 9-cis-epoxycarotenoid dioxygenase (NCED) gene, controlling the rate limiting step of ABA biosynthesis. Moreover, this cultivar exhibited a higher basal activity and a higher induction of aldehyde oxidase isoenzymes (AAO2-AAO3), responsible for converting ABAldehyde to ABA. It was found that the fast activation of the ABA biosynthesis in the roots generated an enhanced ABA pool in the shoot, which brought about a faster closure of the stomata upon increasing osmotic stress and, as a result, the plants could maintain ψw in the tissues close to the control level. In contrast, the anisohydric genotype, cv. GK Öthalom, exhibited a moderate induction of ABA biosynthesis in the roots, leading to the maintenance but no increase in the concentration of ABA on the basis of tissue water content in the leaves. Due to the slower response of their stomata to water deficit, the tissues of cv. GK Öthalom have to acclimate to much more negative water potentials during increasing osmotic stress. A decreased activity of superoxide dismutase (SOD) was found in the leaves and roots of both cultivars exposed to osmotic stress, but in the roots elevated activities of catalase (CAT), peroxidase (POX), glutathione reductase (GR) and glutathione transferase (GST) were detected in

  15. ABA Suppresses Root Hair Growth via the OBP4 Transcriptional Regulator1[OPEN

    PubMed Central

    Kawamura, Ayako; Schäfer, Sabine; Breuer, Christian; Shibata, Michitaro; Mitsuda, Nobutaka; Ohme-Takagi, Masaru; Matsui, Minami

    2017-01-01

    Plants modify organ growth and tune morphogenesis in response to various endogenous and environmental cues. At the cellular level, organ growth is often adjusted by alterations in cell growth, but the molecular mechanisms underlying this control remain poorly understood. In this study, we identify the DNA BINDING WITH ONE FINGER (DOF)-type transcription regulator OBF BINDING PROTEIN4 (OBP4) as a repressor of cell growth. Ectopic expression of OBP4 in Arabidopsis (Arabidopsis thaliana) inhibits cell growth, resulting in severe dwarfism and the repression of genes involved in the regulation of water transport, root hair development, and stress responses. Among the basic helix-loop-helix transcription factors known to control root hair growth, OBP4 binds the ROOT HAIR DEFECTIVE6-LIKE2 (RSL2) promoter to repress its expression. The accumulation of OBP4 proteins is detected in expanding root epidermal cells, and its expression level is increased by the application of abscisic acid (ABA) at concentrations sufficient to inhibit root hair growth. ABA-dependent induction of OBP4 is associated with the reduced expression of RSL2. Furthermore, ectopic expression of OBP4 or loss of RSL2 function results in ABA-insensitive root hair growth. Taken together, our results suggest that OBP4-mediated transcriptional repression of RSL2 contributes to the ABA-dependent inhibition of root hair growth in Arabidopsis. PMID:28167701

  16. Transcriptome profiling identifies ABA mediated regulatory changes towards storage filling in developing seeds of castor bean (Ricinus communis L.)

    PubMed Central

    2014-01-01

    Background The potential biodiesel plant castor bean (Ricinus communis) has been in the limelight for bioenergy research due to the availability of its genome which raises the bar for genome-wide studies claiming advances that impact the “genome-phenome challenge”. Here we report the application of phytohormone ABA as an exogenous factor for the improvement of storage reserve accumulation with a focus on the complex interaction of pathways associated with seed filling. Results After the application of exogenous ABA treatments, we measured an increased ABA levels in the developing seeds cultured in vitro using the ELISA technique and quantified the content of major biomolecules (including total lipids, sugars and protein) in treated seeds. Exogenous ABA (10 μM) enhanced the accumulation of soluble sugar content (6.3%) followed by deposition of total lipid content (4.9 %). To elucidate the possible ABA signal transduction pathways towards overall seed filling, we studied the differential gene expression analysis using Illumina RNA-Sequencing technology, resulting in 2568 (1507-up/1061-down regulated) differentially expressed genes were identified. These genes were involved in sugar metabolism (such as glucose-6-phosphate, fructose 1,6 bis-phosphate, glycerol-3-phosphate, pyruvate kinase), lipid biosynthesis (such as ACS, ACBP, GPAT2, GPAT3, FAD2, FAD3, SAD1 and DGAT1), storage proteins synthesis (such as SGP1, zinc finger protein, RING H2 protein, nodulin 55 and cytochrome P450), and ABA biosynthesis (such as NCED1, NCED3 and beta carotene). Further, we confirmed the validation of RNA-Sequencing data by Semi-quantitative RT-PCR analysis. Conclusions Taken together, metabolite measurements supported by genes and pathway expression results indicated in this study provide new insights to understand the ABA signaling mechanism towards seed storage filling and also contribute useful information for facilitating oilseed crop functional genomics on an aim for utilizing

  17. Age-induced loss of wound-healing ability in potato tubers is partly regulated by ABA.

    PubMed

    Kumar, G N Mohan; Lulai, Edward C; Suttle, Jeffrey C; Knowles, N Richard

    2010-11-01

    Wounding of potato (Solanum tuberosum L.) tubers induces the development of a suberized closing layer and wound periderm that resists desiccation and microbial invasion. Wound-healing ability declines with tuber age (storage period). The mechanism of loss in healing capacity with age is not known; however, upregulation of superoxide production, increased ABA biosynthesis and phenylalanine ammonia lyase (PAL) activity in response to wounding are processes critical to the development of a suberized closing layer and wound periderm. Therefore, the role of ABA in modulating the age-induced loss of wound-healing ability of tubers was examined. Non-wounded older tubers had 86% less ABA (dry matter basis) than younger tubers. PAL transcript increased in younger tubers within 24 h of wounding, but transcription was delayed by 5 days in older tubers. Wound-induced PAL activity increased more rapidly in younger than older tubers. ABA treatment increased PAL expression and activity in tissue from both ages of tubers and restored the 24 h transcription time line in older tubers. Moreover, ABA treatment of wounded older tubers enhanced their resistance to water vapor loss following a 6-day wound-healing period. Wound-induced accumulation of suberin poly(phenolic(s)) (SPP) and suberin poly(aliphatic(s)) (SPA) was measurably slower in older versus younger tubers. ABA treatment hastened SPP accumulation in older tubers to match that in younger tubers, but only enhanced SPA accumulations over the initial 4 days of healing. Age-induced loss of wound-healing ability is thus partly due to reduced ability to accumulate ABA and modulate the production of SPP through PAL in response to wounding and to dysfunction in the downstream signaling events that couple SPA biosynthesis and/or deposition to ABA. ABA treatment partly restored the healing ability of older tubers by enhancing the accumulation of SPP without restoring wound-induced superoxide forming ability to the level of younger

  18. The miR165/166 Mediated Regulatory Module Plays Critical Roles in ABA Homeostasis and Response in Arabidopsis thaliana

    PubMed Central

    Zhou, Jianping; Yang, Yu; Tang, Guiliang; Bressan, Ray A.

    2016-01-01

    The function of miR165/166 in plant growth and development has been extensively studied, however, its roles in abiotic stress responses remain largely unknown. Here, we report that reduction in the expression of miR165/166 conferred a drought and cold resistance phenotype and hypersensitivity to ABA during seed germination and post-germination seedling development. We further show that the ABA hypersensitive phenotype is associated with a changed transcript abundance of ABA-responsive genes and a higher expression level of ABI4, which can be directly regulated by a miR165/166 target. Additionally, we found that reduction in miR165/166 expression leads to elevated ABA levels, which occurs at least partially through the increased expression of BG1, a gene that is directly regulated by a miR165/166 target. Taken together, our results uncover a novel role for miR165/166 in the regulation of ABA and abiotic stress responses and control of ABA homeostasis. PMID:27812104

  19. Characterization of the ABA-regulated global responses to dehydration in Arabidopsis by metabolomics.

    PubMed

    Urano, Kaoru; Maruyama, Kyonoshin; Ogata, Yoshiyuki; Morishita, Yoshihiko; Takeda, Migiwa; Sakurai, Nozomu; Suzuki, Hideyuki; Saito, Kazuki; Shibata, Daisuke; Kobayashi, Masatomo; Yamaguchi-Shinozaki, Kazuko; Shinozaki, Kazuo

    2009-03-01

    Drought is the major environmental threat to agricultural production and distribution worldwide. Adaptation by plants to dehydration stress is a complex biological process that involves global changes in gene expression and metabolite composition. Here, using one type of functional genomics analysis, metabolomics, we characterized the metabolic phenotypes of Arabidopsis wild-type and a knockout mutant of the NCED3 gene (nc3-2) under dehydration stress. NCED3 plays a role in the dehydration-inducible biosynthesis of abscisic acid (ABA), a phytohormone that is important in the dehydration-stress response in higher plants. Metabolite profiling performed using two types of mass spectrometry (MS) systems, gas chromatography/time-of-flight MS (GC/TOF-MS) and capillary electrophoresis MS (CE-MS), revealed that accumulation of amino acids depended on ABA production, but the level of the oligosaccharide raffinose was regulated by ABA independently under dehydration stress. Metabolic network analysis showed that global metabolite-metabolite correlations occurred in dehydration-increased amino acids in wild-type, and strong correlations with raffinose were reconstructed in nc3-2. An integrated metabolome and transcriptome analysis revealed ABA-dependent transcriptional regulation of the biosynthesis of the branched-chain amino acids, saccharopine, proline and polyamine. This metabolomics analysis revealed new molecular mechanisms of dynamic metabolic networks in response to dehydration stress.

  20. Functional dissection of an abscisic acid (ABA)-inducible gene reveals two independent ABA-responsive complexes each containing a G-box and a novel cis-acting element.

    PubMed Central

    Shen, Q; Ho, T H

    1995-01-01

    To elucidate the mechanism by which abscisic acid (ABA) regulates gene expression, the promoter of the barley ABA-responsive HVA22 gene has been analyzed by both loss- and gain-of-function studies. Previous reports indicate that G-box sequences, which are present in genes responding to a variety of environmental and physiological cues, are involved in ABA response. However, our data suggest that G-box sequences are necessary but not sufficient for ABA response. Instead, an ABA response complex consisting of a G-box, namely, ABRE3 (GCCACGTACA), and a novel coupling element, CE1 (TGCCACCGG), is sufficient for high-level ABA induction, and replacement of either of these sequences abolishes ABA responsiveness. We suggest that the interaction between G-box sequences, such as ABRE3 in the HVA22 gene, and CE-type sequences determines the specificity in ABA-regulated gene expression. Our results also demonstrate that the ABA response complex is the minimal promoter unit governing high-level ABA induction; four copies of this 49-bp-long complex linked to a minimal promoter can confer more than 100-fold ABA-induced gene expression. In addition to ABA response complex 1, composed of ABRE3 and CE1, the HVA22 promoter contains another ABA response complex. The ABA responsiveness of this ABA response complex 2 relies on the interaction of G-box (ABRE2; CGCACGTGTC) with another yet unidentified coupling element. These two complexes contribute incrementally to the expression level of HVA22 in response to ABA. PMID:7734964

  1. Comprehensive Analysis of ABA Effects on Ethylene Biosynthesis and Signaling during Tomato Fruit Ripening

    PubMed Central

    Bu, Jianwen; Jiang, Yuanyuan; Khan, Zia Ullah; Luo, Zisheng; Mao, Linchun; Ying, Tiejin

    2016-01-01

    ABA has been widely acknowledged to regulate ethylene biosynthesis and signaling during fruit ripening, but the molecular mechanism underlying the interaction between these two hormones are largely unexplored. In the present study, exogenous ABA treatment obviously promoted fruit ripening as well as ethylene emission, whereas NDGA (Nordihydroguaiaretic acid, an inhibitor of ABA biosynthesis) application showed the opposite biological effects. Combined RNA-seq with time-course RT-PCR analysis, our study not only helped to illustrate how ABA regulated itself at the transcription level, but also revealed that ABA can facilitate ethylene production and response probably by regulating some crucial genes such as LeACS4, LeACO1, GR and LeETR6. In addition, investigation on the fruits treated with 1-MCP immediately after ABA exposure revealed that ethylene might be essential for the induction of ABA biosynthesis and signaling at the onset of fruit ripening. Furthermore, some specific transcription factors (TFs) known as regulators of ethylene synthesis and sensibility (e.g. MADS-RIN, TAGL1, CNR and NOR) were also observed to be ABA responsive, which implied that ABA influenced ethylene action possibly through the regulation of these TFs expression. Our comprehensive physiological and molecular-level analysis shed light on the mechanism of cross-talk between ABA and ethylene during the process of tomato fruit ripening. PMID:27100326

  2. Comprehensive Analysis of ABA Effects on Ethylene Biosynthesis and Signaling during Tomato Fruit Ripening.

    PubMed

    Mou, Wangshu; Li, Dongdong; Bu, Jianwen; Jiang, Yuanyuan; Khan, Zia Ullah; Luo, Zisheng; Mao, Linchun; Ying, Tiejin

    2016-01-01

    ABA has been widely acknowledged to regulate ethylene biosynthesis and signaling during fruit ripening, but the molecular mechanism underlying the interaction between these two hormones are largely unexplored. In the present study, exogenous ABA treatment obviously promoted fruit ripening as well as ethylene emission, whereas NDGA (Nordihydroguaiaretic acid, an inhibitor of ABA biosynthesis) application showed the opposite biological effects. Combined RNA-seq with time-course RT-PCR analysis, our study not only helped to illustrate how ABA regulated itself at the transcription level, but also revealed that ABA can facilitate ethylene production and response probably by regulating some crucial genes such as LeACS4, LeACO1, GR and LeETR6. In addition, investigation on the fruits treated with 1-MCP immediately after ABA exposure revealed that ethylene might be essential for the induction of ABA biosynthesis and signaling at the onset of fruit ripening. Furthermore, some specific transcription factors (TFs) known as regulators of ethylene synthesis and sensibility (e.g. MADS-RIN, TAGL1, CNR and NOR) were also observed to be ABA responsive, which implied that ABA influenced ethylene action possibly through the regulation of these TFs expression. Our comprehensive physiological and molecular-level analysis shed light on the mechanism of cross-talk between ABA and ethylene during the process of tomato fruit ripening.

  3. [Accumulation of ABA and ODAP in Lathyrus sativus under water stress].

    PubMed

    Xing, G; Zhou, G; Li, Z; Cui, K

    2000-10-01

    The roots of fifteen days old Lathyrus sativus seedlings were treated by PEG, PEG + ABA and ABA, and their leaves were sampled to determine the contents of endogenic ABA, ODAP, MDA and H2O2 and the activity of superoxide dismutase, catalase, peroxidase and glutathione reductase. The results showed that after treated, the contents of ABA and ODAP in leaves increased markedly. The addition of exogenous ABA decreased the increment of MDA and H2O2 contents and retarded the attenuation of CAT activity, which were induced by PEG stress, and enhanced the GR activity. In addition, when materials were treated with exogenous ABA in a long time, the ABA content in leaves was increased markedly, and ODAP was then accumulated. There was no significant effect on metabolism of active oxygen in the early days(0-3 days) of ABA treatment, but the activities of SOD, POD, CAT and GR decreased, and the contents of MDA and H2O2 increased in leaves of Lathyrus sativus with the duration of ABA treatment(7-15 days). The results indicated that ABA could promote the accumulation of ODAP in leaves of Lathyrus sativus.

  4. GSTF1 Gene Expression Analysis in Cultivated Wheat Plants under Salinity and ABA Treatments

    PubMed Central

    Niazi, Ali; Ramezani, Amin; Dinari, Ali

    2014-01-01

    Most plants encounter stress such as drought and salinity that adversely affect growth, development and crop productivity. The expression of the gene glutathione-s-transferases (GST) extends throughout various protective mechanisms in plants and allows them to adapt to unfavorable environmental conditions. GSTF1 (the first phi GSTFs class) gene expression patterns in the wheat cultivars Mahuti and Alamut were studied under salt and ABA treatments using a qRT-PCR technique. Results showed that gene expression patterns were significantly different in these two cultivars. Data showed that in Mahuti, there was an increase of transcript accumulation under salt and ABA treatments at 3h, 10h and 72h respectively. In Alamut, however, the pattern of transcript accumulation was different; the maximum was at 3h. In contrast, there were no significant differences observed between the cultivars for GSTF1 gene expression profiles at three levels of NaCl concentration (50, 100, and 200 mM) or in ABA (Abscisic Acid) treatment. It is likely that difference of gene expression patterns between the cultivars (Mahuti as a salt tolerant cultivar and Alamut as a salt sensitive cultivar) is due to distinct signaling pathways which activate GSTF1 expression. Lack of a significant difference between the GSTF1 gene expression profile under salt and ABA treatments suggests that the GSTF1 gene is not induced by stress stimuli. Of course it is possible that other levels of NaCl and ABA treatments cause a change in the GSTF1 gene. PMID:27843973

  5. abaA controls phialide differentiation in Aspergillus nidulans.

    PubMed Central

    Sewall, T C; Mims, C W; Timberlake, W E

    1990-01-01

    Aspergillus nidulans is an ascomycetous fungus that reproduces asexually by forming multicellular conidiophores and uninucleate spores called conidia. Loss of function mutations in the abacus A (abaA) regulatory locus result in formation of aberrant conidiophores that fail to produce conidia. Wild-type conidiophores form two tiers of sterigmata. The first tier, metulae, divide to produce the second tier, phialides. Phialides are sporogenous cells that produce conidia through a specialized apical budding process. We have examined conidiophore development in an abaA- strain at the ultrastructural level. The results showed that in the mutant metulae produce supernumerary tiers of cells with metula-like, rather than phialide-like, properties. Temperature shift experiments with an abaA14ts strain demonstrated that abaA+ function induced phialide formation by the aberrant abacus cells and was continuously required for maintenance of phialide function. In the absence of abaA+ activity, metulae simply proliferated and later developmental steps never occurred. We conclude that abaA+ directs the differentiation of phialides and is continuously required for maintenance of their function. PMID:2152124

  6. ABA inhibits entry into stomatal-lineage development in Arabidopsis leaves.

    PubMed

    Tanaka, Yoko; Nose, Tomoe; Jikumaru, Yusuke; Kamiya, Yuji

    2013-05-01

    The number and density of stomata are controlled by endogenous and environmental factors. Despite recent advances in our understanding of stomatal development, mechanisms which prevent stomatal-lineage entry remain unclear. Here, we propose that abscisic acid (ABA), a phytohormone known to induce stomatal closure, limits initiation of stomatal development and induces enlargement of pavement cells in Arabidopsis cotyledons. An ABA-deficient aba2-2 mutant had an increased number/proportion of stomata within a smaller cotyledon, as well as reduced expansion of pavement cells. This tendency was reversed after ABA application or in an ABA over-accumulating cyp707a1cyp707a3 doublemutant. Our time course analysis revealed that aba2-2 shows prolonged formation of meristemoids and guard mother cells, both precursors of stoma. This finding is in accordance with prolonged gene expression of SPCH and MUTE, master regulators for stomatal formation, indicating that ABA acts upstream of these genes. Only aba2-2 mute, but not aba2-2 spch double mutant showed additive phenotypes and displayed inhibition of pavement cell enlargement with increased meristemoid number, indicating that ABA action on pavement cell expansion requires the presence of stomatal-lineage cells.

  7. The ABA receptors -- we report you decide.

    PubMed

    McCourt, Peter; Creelman, Robert

    2008-10-01

    The plant hormone abscisic acid (ABA) has been implicated in a variety of physiological responses ranging from seed dormancy to stomatal conductance. Recently, three groups have reported the molecular identification of three disparate ABA receptors. Unlike the identification of other hormone receptors, in these three cases high affinity binding to ABA rather than the isolation of ABA insensitive mutants led to these receptor genes. Interestingly, two of the receptors encode genes involved in floral timing and chlorophyll biosynthesis, which are not considered traditional ABA responses. And the third receptor has been clouded in issues of its molecular identity. To clearly determine the roles of these genes in ABA perception it will require placing of these ABA-binding proteins into the rich ABA physiological context that has built up over the years.

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

    PubMed Central

    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

  9. ABA Receptors: Past, Present and Future

    SciTech Connect

    Guo, Jianjun; Yang, Xiaohan; Weston, David; Chen, Jay

    2011-01-01

    Abscisic acid (ABA) is the key plant stress hormone. Consistent with the earlier studies in support of the presence of both membrane- and cytoplasm-localized ABA receptors, recent studies have identified multiple ABA receptors located in various subcellular locations. These include a chloroplast envelope-localized receptor (the H subunit of Chloroplast Mg2+-chelatase/ABA Receptor), two plasma membrane-localized receptors (G-protein Coupled Receptor 2 and GPCR-type G proteins), and one cytosol/nucleus-localized Pyrabactin Resistant (PYR)/PYR-Like (PYL)/Regulatory Component of ABA Receptor 1 (RCAR). Although the downstream molecular events for most of the identified ABA receptors are currently unknown, one of them, PYR/PYL/RACR was found to directly bind and regulate the activity of a long-known central regulator of ABA signaling, the A-group protein phosphatase 2C (PP2C). Together with the Sucrose Non-fermentation Kinase Subfamily 2 (SnRK2s) protein kinases, a central signaling complex (ABA-PYR-PP2Cs-SnRK2s) that is responsible for ABA signal perception and transduction is supported by abundant genetic, physiological, biochemical and structural evidence. The identification of multiple ABA receptors has advanced our understanding of ABA signal perception and transduction while adding an extra layer of complexity.

  10. Ethylene-dependent/ethylene-independent ABA regulation of tomato plants colonized by arbuscular mycorrhiza fungi.

    PubMed

    Martín-Rodríguez, José Ángel; León-Morcillo, Rafael; Vierheilig, Horst; Ocampo, Juan Antonio; Ludwig-Müller, Jutta; García-Garrido, José Manuel

    2011-04-01

    We investigated the relationship between ABA and ethylene regulating the formation of the arbuscular mycorrhiza (AM) symbiosis in tomato (Solanum lycopersicum) plants and tried to define the specific roles played by each of these phytohormones in the mycorrhization process. We analysed the impact of ABA biosynthesis inhibition on mycorrhization by Glomus intraradices in transgenic tomato plants with an altered ethylene pathway. We also studied the effects on mycorrhization in sitiens plants treated with the aminoethoxyvinyl glycine hydrochloride (AVG) ethylene biosynthesis inhibitor and supplemented with ABA. In addition, the expression of plant and fungal genes involved in the mycorrhization process was studied. ABA biosynthesis inhibition qualitatively altered the parameters of mycorrhization in accordance with the plant's ethylene perception and ethylene biosynthesis abilities. Inhibition of ABA biosynthesis in wild-type plants negatively affected all the mycorrhization parameters studied, while tomato mutants impaired in ethylene synthesis only showed a reduced arbuscular abundance in mycorrhizal roots. Inhibition of ethylene synthesis in ABA-deficient sitiens plants increased the intensity of mycorrhiza development, while ABA application rescued arbuscule abundance in the root's mycorrhizal zones. The results of our study show an antagonistic interaction between ABA and ethylene, and different roles of each of the two hormones during AM formation. This suggests that a dual ethylene-dependent/ethylene-independent mechanism is involved in ABA regulation of AM formation.

  11. The rose (Rosa hybrida) NAC transcription factor 3 gene, RhNAC3, involved in ABA signaling pathway both in rose and Arabidopsis.

    PubMed

    Jiang, Guimei; Jiang, Xinqiang; Lü, Peitao; Liu, Jitao; Gao, Junping; Zhang, Changqing

    2014-01-01

    Plant transcription factors involved in stress responses are generally classified by their involvement in either the abscisic acid (ABA)-dependent or the ABA-independent regulatory pathways. A stress-associated NAC gene from rose (Rosa hybrida), RhNAC3, was previously found to increase dehydration tolerance in both rose and Arabidopsis. However, the regulatory mechanism involved in RhNAC3 action is still not fully understood. In this study, we isolated and analyzed the upstream regulatory sequence of RhNAC3 and found many stress-related cis-elements to be present in the promoter, with five ABA-responsive element (ABRE) motifs being of particular interest. Characterization of Arabidopsis thaliana plants transformed with the putative RhNAC3 promoter sequence fused to the β-glucuronidase (GUS) reporter gene revealed that RhNAC3 is expressed at high basal levels in leaf guard cells and in vascular tissues. Moreover, the ABRE motifs in the RhNAC3 promoter were observed to have a cumulative effect on the transcriptional activity of this gene both in the presence and absence of exogenous ABA. Overexpression of RhNAC3 in A. thaliana resulted in ABA hypersensitivity during seed germination and promoted leaf closure after ABA or drought treatments. Additionally, the expression of 11 ABA-responsive genes was induced to a greater degree by dehydration in the transgenic plants overexpressing RhNAC3 than control lines transformed with the vector alone. Further analysis revealed that all these genes contain NAC binding cis-elements in their promoter regions, and RhNAC3 was found to partially bind to these putative NAC recognition sites. We further found that of 219 A. thaliana genes previously shown by microarray analysis to be regulated by heterologous overexpression RhNAC3, 85 are responsive to ABA. In rose, the expression of genes downstream of the ABA-signaling pathways was also repressed in RhNAC3-silenced petals. Taken together, we propose that the rose RhNAC3 protein

  12. Assessment battery for communication (ABaCo): normative data.

    PubMed

    Angeleri, Romina; Bosco, Francesca M; Gabbatore, Ilaria; Bara, Bruno G; Sacco, Katiuscia

    2012-09-01

    The Assessment Battery for Communication (ABaCo) was introduced to evaluate pragmatic abilities in patients with cerebral lesions. The battery is organized into five evaluation scales focusing on separate components of pragmatic competence. In the present study, we present normative data for individuals 15-75 years of age (N = 300). The sample was stratified by age, sex, and years of education, according to Italian National Institute of Statistics indications in order to be representative of the general national population. Since performance on the ABaCo decreases with age and lower years of education, the norms were stratified for both age and education. The ABaCo is a valuable tool in clinical practice; the normative data provided here will enable clinicians to determine different kinds and specific levels of communicative impairments more precisely.

  13. Douglass Developmental Disabilities Center: An ABA Program for Children and Adults with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Handleman, Jan S.; Harris, Sandra L.

    2005-01-01

    There is increasing evidence that Applied Behavior Analysis (ABA) is an effective, and often superior, method to teach children with Autism Spectrum Disorders ASD), than other methods. The Douglass Developmental Disabilities Center of Rutgers University (DDDC) has been using ABA for more than thirty years to teach toddlers, young children,…

  14. Leaf gas exchange and ABA accumulation in Phaseolus vulgaris genotypes of contrasting drought tolerance

    SciTech Connect

    Bertrand, A.; Castonguay, Y.; Nadeau, P. )

    1991-05-01

    Drought tolerance mechanisms in Phaseolus vulgaris (Pv) are still largely unknown. Gas exchange responses and ABA accumulation were monitored in Pv genotypes differing in their drought adaptation. Higher rates of photosynthesis were observed under well-watered conditions in drought sensitive genotypes. Water stress caused a significant reduction in leaf water potential and photosynthetic rates regardless of drought adaptation. Higher photosynthetic rates were maintained under stress conditions in one drought tolerant genotype. Interestingly water stress caused significant ABA accumulation only in this genotype. Root ABA levels were similar among genotypes and were not modified by water stress. Endogenous levels of free ABA in leaves and roots did not correlated with gas exchange response to water stress. These results differ from previous reports on genotypic variation in ABA accumulation under water stress.

  15. Can protein levels be economically increased?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One result from the 2010 hard red winter wheat harvest was an increase of discussions on protein values across the southern great plains. The crop garnered relatively low protein values for several reasons, many of which were directly related to the weather patterns and environmental conditions. T...

  16. The HAB1 PP2C is inhibited by ABA-dependent PYL10 interaction.

    PubMed

    Li, Juan; Shi, Chaowei; Sun, Demeng; He, Yao; Lai, Chaohua; Lv, Pei; Xiong, Ying; Zhang, Longhua; Wu, Fangming; Tian, Changlin

    2015-06-05

    PYL10 is a monomeric abscisic acid (ABA) receptor that inhibits protein phosphatase 2C (PP2C) activity in Arabidopsis thaliana. Previous studies reported that the PP2C phosphatase inhibition by PYL10 was ABA-independent. Here, systematic PYL10 biochemical studies demonstrated that PYL10 activity was ABA-dependent, and the previously reported studies was interfered by the presence of BSA in the commercial kit. To investigate dynamic mechanism of how ABA binding to PYL10 induces PP2C phosphatase inhibiting activity, solution NMR relaxation analysis of apo-PYL10 and PYL10/ABA were conducted following backbone resonance assignments. Reduced spectrum density mapping of the backbone relaxation data revealed that PYL10 was more flexible in ABA bound form than apo-PYL10, indicating an increased conformational entropy upon ligand binding. Moreover, to illustrate conformation exchanges of PYL10 upon ABA binding, NMR line shape analysis was performed with increasing concentrations of ABA, and the results indicated that PYL10 backbone conformational changes occur at different time scales.

  17. Antagonistic effect of polyamines on ABA-induced suppression of mitosis in Allium cepa L.

    PubMed

    Mahajan, Arpana; Sharma, Shashi

    2009-02-01

    Effect of abscisic acid (ABA) and polyamines (PAs) [putrescine (Put), spermidine (Spd) and spermine (Spm)] on mitosis in root tips of A. cepa was studied. Treatment with ABA (0.1 to 100 microM) for 24 hr suppressed the mitosis, measured as mitotic index (MI), in a concentration-dependent manner with approx. 50% suppression at 10 microM of ABA. Treatment with different PAs (1 to 100 microM) had differential mitosis suppression effect. Spm was most inhibitory followed by Spd and Put, respectively. The higher concentrations of PAs (1 mM Put; 0.1 and 1 mM Spd or Spm) caused cell distortion. Remarkably, a 24 hr pretreatment of root tips with PAs prior to ABA (100 microM) treatment resulted in a general concentration-dependent reversal of ABA-induced suppression of MI. Catalase (CAT) activity in the root tips, an indicator of redox metabolism, increased due to ABA treatment in a concentration-dependent manner, remained unaltered in response to Put and declined due to Spd and Spm (> or = 0.1 mM). However, all PAs, irrespective of their individual effects, generally antagonized the ABA-dependent increase in CAT activity. Data indicate the possibility of ABA-PA interaction in the regulation of mitosis.

  18. GsSKP21, a Glycine soja S-phase kinase-associated protein, mediates the regulation of plant alkaline tolerance and ABA sensitivity.

    PubMed

    Liu, Ailin; Yu, Yang; Duan, Xiangbo; Sun, Xiaoli; Duanmu, Huizi; Zhu, Yanming

    2015-01-01

    Plant SKP1-like family proteins, components of the SCF complex E3 ligases, are involved in the regulation of plant development and stress responses. Little is known about the precise function of SKP genes in plant responses to environmental stresses. GsSKP21 was initially identified as a potential stress-responsive gene based on the transcriptome sequencing of Glycine soja. In this study, we found that GsSKP21 protein contains highly conserved SKP domains in its N terminus and an extra unidentified domain in its C terminus. The transcript abundance of GsSKP21, detected by quantitative real-time PCR, was induced under the treatment of alkali and salt stresses. Overexpression of GsSKP21 in Arabidopsis dramatically increased plant tolerance to alkali stress. Furthermore, we found that overexpression of GsSKP21 resulted in decreased ABA sensitivity during both the seed germination and early seedling growth stages. GsSKP21 mediated ABA signaling by altering the expression levels of the ABA signaling-related and ABA-induced genes. We also investigated the tissue expression specificity and subcellular localization of GsSKP21. These results suggest that GsSKP21 is important for plant tolerance to alkali stress and plays a critical regulatory role in the ABA-mediated stress response.

  19. Graphene oxide modulates root growth of Brassica napus L. and regulates ABA and IAA concentration.

    PubMed

    Cheng, Fan; Liu, Yu-Feng; Lu, Guang-Yuan; Zhang, Xue-Kun; Xie, Ling-Li; Yuan, Cheng-Fei; Xu, Ben-Bo

    2016-04-01

    Researchers have proven that nanomaterials have a significant effect on plant growth and development. To better understand the effects of nanomaterials on plants, Zhongshuang 11 was treated with different concentrations of graphene oxide. The results indicated that 25-100mg/l graphene oxide treatment resulted in shorter seminal root length compared with the control samples. The fresh root weight decreased when treated with 50-100mg/l graphene oxide. The graphene oxide treatment had no significant effect on the Malondialdehyde (MDA) content. Treatment with 50mg/l graphene oxide increased the transcript abundance of genes involved in ABA biosynthesis (NCED, AAO, and ZEP) and some genes involved in IAA biosynthesis (ARF2, ARF8, IAA2, and IAA3), but inhibited the transcript levels of IAA4 and IAA7. The graphene oxide treatment also resulted in a higher ABA content, but a lower IAA content compared with the control samples. The results indicated that graphene oxide modulated the root growth of Brassica napus L. and affected ABA and IAA biosynthesis and concentration.

  20. A novel ABA insensitive mutant of Lotus japonicus with a wilty phenotype displays unaltered nodulation regulation.

    PubMed

    Biswas, Bandana; Chan, Pick Kuen; Gresshoff, Peter M

    2009-05-01

    An ABA insensitive mutant, Beyma, was isolated in Lotus japonicus MG-20 from an EMS mutagenesis population using root growth inhibition to applied ABA as the screening criterion. (The name 'Beyma' was taken from the Australian Aboriginal language, Wagiman, beyma, meaning 'drying up'.) The stable mutant that segregates as a dominant Mendelian mutation is insensitive to ABA induced inhibition of germination, vegetative growth, stomatal opening, as well as nodulation. Tissue ABA levels were normal, suggesting a sensitivity rather than biosynthesis mutation. It is slow-growing (50-70% of wild-type MG-20) and has a near-constitutive wilty phenotype associated with its inability to regulate stomatal opening. Whilst showing a wide range of ABA insensitive phenotypes, Beyma did not show alteration of nodule number control, as, in the absence of added ABA, the number and patterning (but not size) of nodules formed in the mutant were similar to that of MG-20. Split root experiments on MG-20 showed that application of ABA on one side of the root inhibited nodulation locally but not systemically. We propose that ABA is not involved directly in systemic autoregulation of nodulation (AON).

  1. Grape hexokinases are involved in the expression regulation of sucrose synthase- and cell wall invertase-encoding genes by glucose and ABA.

    PubMed

    Wang, Xiu-Qin; Zheng, Li-Li; Lin, Hao; Yu, Fei; Sun, Li-Hui; Li, Li-Mei

    2017-02-28

    Hexokinase (HXK, EC 2.7.1.1) is a multifunctional protein that both is involved in catalyzing the first step of glycolysis and plays an important role in sugar signaling. However, the supporting genetic evidence on hexokinases (CsHXKs) from grape (Vitis vinifera L. cv. Cabernet Sauvignon) berries has been lacking. Here, to investigate the role of CsHXK isoforms as glucose (Glc) and abscisic acid (ABA) sensors, we cloned two hexokinase isozymes, CsHXK1 and CsHXK2 with highly conserved genomic structure of nine exons and eight introns. We also found adenosine phosphate binding, substrate recognition and connection sites in their putative proteins. During grape berry development, the expression profiles of two CsHXK isoforms, sucrose synthases (SuSys) and cell wall invertase (CWINV) genes increased concomitantly with high levels of endogenous Glc and ABA. Furthermore, we showed that in wild type grape berry calli (WT), glucose repressed the expression levels of sucrose synthase (SuSy) and cell wall invertase (CWINV) genes, while ABA increased their expression levels. ABA could not only effectively improve the expression levels of SuSy and CWINV, but also block the repression induced by glucose on the expression of both genes. However, after silencing CsHXK1 or CsHXK2 in grape calli, SuSy and CWINV expression were enhanced, and the expressions of the two genes are insensitive in response to Glc treatment. Interestingly, exogenous ABA alone could not or less increase SuSy and CWINV expression in silencing CsHXK1 or CsHXK2 grape calli compared to WT. Meantime, ABA could not block the repression induced by glucose on the expression of SuSy and CWINV in CsHXK1 or CsHXK2 mutants. Therefore, Glc signal transduction depends on the regulation of CsHXK1 or CsHXK2. ABA signal was also disturbed by CsHXK1 or CsHXK2 silencing. The present results provide new insights into the regulatory role of Glc and ABA on the enzymes related to sugar metabolism in grape berry.

  2. ABA in bryophytes: how a universal growth regulator in life became a plant hormone?

    PubMed

    Takezawa, Daisuke; Komatsu, Kenji; Sakata, Yoichi

    2011-07-01

    Abscisic acid (ABA) is not a plant-specific compound but one found in organisms across kingdoms from bacteria to animals, suggesting that it is a ubiquitous and versatile substance that can modulate physiological functions of various organisms. Recent studies have shown that plants developed an elegant system for ABA sensing and early signal transduction mechanisms to modulate responses to environmental stresses for survival in terrestrial conditions. ABA-induced increase in stress tolerance has been reported not only in vascular plants but also in non-vascular bryophytes. Since bryophytes are the key group of organisms in the context of plant evolution, clarification of their ABA-dependent processes is important for understanding evolutionary adaptation of land plants. Molecular approaches using Physcomitrella patens have revealed that ABA plays a role in dehydration stress tolerance in mosses, which comprise a major group of bryophytes. Furthermore, we recently reported that signaling machinery for ABA responses is also conserved in liverworts, representing the most basal members of extant land plant lineage. Conservation of the mechanism for ABA sensing and responses in angiosperms and basal land plants suggests that acquisition of this mechanism for stress tolerance in vegetative tissues was one of the critical evolutionary events for adaptation to the land. This review describes the role of ABA in basal land plants as well as non-land plant organisms and further elaborates on recent progress in molecular studies of model bryophytes by comparative and functional genomic approaches.

  3. Jasmonic acid accumulation and systemic photosynthetic and electrical changes in locally burned wild type tomato, ABA-deficient sitiens mutants and sitiens pre-treated by ABA.

    PubMed

    Hlavinka, Jan; Nožková-Hlaváčková, Vladimíra; Floková, Kristýna; Novák, Ondřej; Nauš, Jan

    2012-05-01

    Burning the terminal leaflet of younger tomato (Lycopersicon esculentum Mill.) leaf caused local and systemic changes in the surface electrical potential (SEP) and gas exchange (GE) parameters. The local and systemic accumulation of endogenous abscisic acid (ABA) and jasmonic acid (JA) was measured 85 min after burning. The experiments were conducted with wild type (WT) plants, ABA-deficient mutant sitiens (SIT) and ABA pre-treated SIT plants (SITA). First changes in SEP were detected within 1.5 min after burning and were followed by a decrease in GE parameters within 3-6 min in WT, SIT and SITA plants. GE and SEP time courses of SIT were different and wave amplitudes of SEP of SIT were lower compared to WT and SITA. ABA content in WT and SITA control plants was similar and substantially higher compared to SIT, JA content was similar among WT, SIT and SITA. While changes in the ABA content in systemic leaves have not been recorded after burning, the systemic JA content was substantially increased in WT and more in SIT and SITA. The results suggest that ABA content governs the systemic reaction of GE and the SEP shape upon local burning. ABA, JA and SEP participate in triggering the GE reaction. The ABA shortage in the SIT in the reaction to burning is partly compensated by an enhanced JA accumulation. This JA compensation is maintained even in SIT endogenously supplied with ABA. A correlation between the systemic JA content and changes in GE parameters or SEP was not found.

  4. Identification and mechanism of ABA receptor antagonism

    SciTech Connect

    Melcher, Karsten; Xu, Yong; Ng, Ley-Moy; Zhou, X. Edward; Soon, Fen-Fen; Chinnusamy, Viswanathan; Suino-Powell, Kelly M; Kovach, Amanda; Tham, Fook S.; Cutler, Sean R.; Li, Jun; Yong, Eu-Leong; Zhu, Jian-Kang; Xu, H. Eric

    2010-11-11

    The phytohormone abscisic acid (ABA) functions through a family of fourteen PYR/PYL receptors, which were identified by resistance to pyrabactin, a synthetic inhibitor of seed germination. ABA activates these receptors to inhibit type 2C protein phosphatases, such as ABI1, yet it remains unclear whether these receptors can be antagonized. Here we demonstrate that pyrabactin is an agonist of PYR1 and PYL1 but is unexpectedly an antagonist of PYL2. Crystal structures of the PYL2-pyrabactin and PYL1-pyrabactin-ABI1 complexes reveal the mechanism responsible for receptor-selective activation and inhibition, which enables us to design mutations that convert PYL1 to a pyrabactin-inhibited receptor and PYL2 to a pyrabactin-activated receptor and to identify new pyrabactin-based ABA receptor agonists. Together, our results establish a new concept of ABA receptor antagonism, illustrate its underlying mechanisms and provide a rational framework for discovering novel ABA receptor ligands.

  5. ABA-mediated heterophylly is regulated by differential expression of 9-cis-epoxycarotenoid dioxygenase 3 in lilies.

    PubMed

    Chen, Hung-Chi; Hwang, San-Gwang; Chen, Shiau-Ming; Shii, Chou-Tou; Cheng, Wan-Hsing

    2011-10-01

    Although exogenous ABA-regulated heterophylly has been well documented in multiple plant species, the effect of endogenous ABA and its molecular mechanism remain uncharacterized. In the present study, the effects of endogenous ABA on heterophyllous switching were investigated in two different lily varieties, Lilium formosanum and Lilium oriental hybrid 'Casa Blanca'. Seedlings of L. formosanum, which have scale-leaf-type growth, displayed low levels of both 9-cis-epoxycarotenoid dioxygenase 3 (LfNCED3) transcripts and ABA, whereas seedlings of L. oriental hybrid 'Casa Blanca', which have scale-type growth, displayed high levels of both LoNCED3 transcripts and ABA. Sucrose induced endogenous ABA production in cultured lilies; low ABA induction shows scale-leaf-type growth, whereas scale-type growth becomes predominant when ABA levels are high. Heterologous expression of either LfNCED3 or LoNCED3 was found to complement the Arabidopsis Atnced3 mutant. Interestingly, the expression patterns of LfNCED3 and LoNCED3 in transgenic Arabidopsis plants are distinguishable. Further promoter analysis revealed that a putative E2F-like element in the LfNCED3 promoter, but not in the LoNCED3 promoter, plays a negative role in controlling its activity. Collectively, our results demonstrate that NCED3 plays a key role in ABA-mediated heterophylly in lilies.

  6. Cross-species approaches to seed dormancy and germination: conservation and biodiversity of ABA-regulated mechanisms and the Brassicaceae DOG1 genes.

    PubMed

    Graeber, Kai; Linkies, Ada; Müller, Kerstin; Wunchova, Andrea; Rott, Anita; Leubner-Metzger, Gerhard

    2010-05-01

    Seed dormancy is genetically determined with substantial environmental influence mediated, at least in part, by the plant hormone abscisic acid (ABA). The ABA-related transcription factor ABI3/VP1 (ABA INSENSITIVE3/VIVIPAROUS1) is widespread among green plants. Alternative splicing of its transcripts appears to be involved in regulating seed dormancy, but the role of ABI3/VP1 goes beyond seeds and dormancy. In contrast, DOG1 (DELAY OF GERMINATION 1), a major quantitative trait gene more specifically involved in seed dormancy, was so far only known from Arabidopsis thaliana (AtDOG1) and whether it also has roles during the germination of non-dormant seeds was not known. Seed germination of Lepidium sativum ('garden cress') is controlled by ABA and its antagonists gibberellins and ethylene and involves the production of apoplastic hydroxyl radicals. We found orthologs of AtDOG1 in the Brassicaceae relatives L. sativum (LesaDOG1) and Brassica rapa (BrDOG1) and compared their gene structure and the sequences of their transcripts expressed in seeds. Tissue-specific analysis of LesaDOG1 transcript levels in L. sativum seeds showed that they are degraded upon imbibition in the radicle and the micropylar endosperm. ABA inhibits germination in that it delays radicle protrusion and endosperm weakening and it increased LesaDOG1 transcript levels during early germination due to enhanced transcription and/or inhibited degradation. A reduced decrease in LesaDOG1 transcript levels upon ABA treatment is evident in the late germination phase in both tissues. This temporal and ABA-related transcript expression pattern suggests a role for LesaDOG1 in the control of germination timing of non-dormant L. sativum seeds. The possible involvement of the ABA-related transcription factors ABI3 and ABI5 in the regulation of DOG1 transcript expression is discussed. Other species of the monophyletic genus Lepidium showed coat or embryo dormancy and are therefore highly suited for comparative

  7. Chemical Promotion of Endogenous Amounts of ABA in Arabidopsis thaliana by a Natural Product, Theobroxide.

    PubMed

    Yamashita, Yudai; Ota, Maremichi; Inoue, Yutaka; Hasebe, Youko; Okamoto, Masanori; Inukai, Tsuyoshi; Masuta, Chikra; Sakihama, Yasuko; Hashidoko, Yasuyuki; Kojima, Mikiko; Sakakibara, Hitoshi; Inage, Yasuyuki; Takahashi, Kosaku; Yoshihara, Teruhiko; Matsuura, Hideyuki

    2016-05-01

    Plant hormones are a group of structurally diverse small compounds that orchestrate the cellular processes governing proper plant growth and environmental adaptation. To understand the details of hormonal activity, we must study not only their inherent activities but also the cross-talk among plant hormones. In addition to their use in agriculture, plant chemical activators, such as probenazole and uniconazole, have made great contributions to understand hormonal cross-talk. However, the use of plant chemical activators is limited due to the lack of activators for certain hormones. For example, to the best of our knowledge, there are only a few chemical activators previously known to stimulate the accumulation of ABA in plants, such as absinazoles and proanthocyanidins. In many cases, antagonistic effects have been examined in experiments using exogenously applied ABA, although these studies did not account for biologically relevant concentrations. In this report, it was found that a natural product, theobroxide, had potential as a plant chemical activator for stimulating the accumulation of ABA. Using theobroxide, the antagonistic effect of ABA against GAs was proved without exogenously applying ABA or using mutant plants. Our results suggest that ABA levels could be chemically controlled to elicit ABA-dependent biological phenomena.

  8. Proteomic analysis reveals differential accumulation of small heat shock proteins and late embryogenesis abundant proteins between ABA-deficient mutant vp5 seeds and wild-type Vp5 seeds in maize

    PubMed Central

    Wu, Xiaolin; Gong, Fangping; Yang, Le; Hu, Xiuli; Tai, Fuju; Wang, Wei

    2014-01-01

    ABA is a major plant hormone that plays important roles during many phases of plant life cycle, including seed development, maturity and dormancy, and especially the acquisition of desiccation tolerance. Understanding of the molecular basis of ABA-mediated plant response to stress is of interest not only in basic research on plant adaptation but also in applied research on plant productivity. Maize mutant viviparous-5 (vp5), deficient in ABA biosynthesis in seeds, is a useful material for studying ABA-mediated response in maize. Due to carotenoid deficiency, vp5 endosperm is white, compared to yellow Vp5 endosperm. However, the background difference at proteome level between vp5 and Vp5 seeds is unclear. This study aimed to characterize proteome alterations of maize vp5 seeds and to identify ABA-dependent proteins during seed maturation. We compared the embryo and endosperm proteomes of vp5 and Vp5 seeds by gel-based proteomics. Up to 46 protein spots, most in embryos, were found to be differentially accumulated between vp5 and Vp5. The identified proteins included small heat shock proteins (sHSPs), late embryogenesis abundant (LEA) proteins, stress proteins, storage proteins and enzymes among others. However, EMB564, the most abundant LEA protein in maize embryo, accumulated in comparable levels between vp5 and Vp5 embryos, which contrasted to previously characterized, greatly lowered expression of emb564 mRNA in vp5 embryos. Moreover, LEA proteins and sHSPs displayed differential accumulations in vp5 embryos: six out of eight identified LEA proteins decreased while nine sHSPs increased in abundance. Finally, we discussed the possible causes of global proteome alterations, especially the observed differential accumulation of identified LEA proteins and sHSPs in vp5 embryos. The data derived from this study provides new insight into ABA-dependent proteins and ABA-mediated response during maize seed maturation. PMID:25653661

  9. FYVE1/FREE1 Interacts with the PYL4 ABA Receptor and Mediates its Delivery to the Vacuolar Degradation Pathway.

    PubMed

    Belda-Palazon, Borja; Rodriguez, Lesia; Fernandez, Maria A; Castillo, Mari-Cruz; Anderson, Erin A; Gao, Caiji; González-Guzmán, Miguel; Peirats-Llobet, Marta; Zhao, Qiong; De Winne, Nancy; Gevaert, Kris; De Jaeger, Geert; Jiang, Liwen; Leon, Jose; Mullen, Robert T; Rodriguez, Pedro L

    2016-08-05

    Recently, we described the ubiquitylation of PYL4 and PYR1 by the RING E3 ubiquitin ligase RSL1 at the plasma membrane of Arabidopsis thaliana. This suggested that ubiquitylated ABA receptors might be targeted to the vacuolar degradation pathway because such ubiquitylation is usually an internalization signal for the endocytic route. Here, we show that FYVE1 (previously termed FREE1), a recently described component of the endosomal sorting complex required for transport (ESCRT) machinery, interacted with RSL1-receptor complexes and recruited PYL4 to endosomal compartments. Although the ESCRT pathway has been assumed to be reserved for integral membrane proteins, we show the involvement of this pathway in the degradation of ABA receptors, which can be associated with membranes but are not integral membrane proteins. Knock-down fyve1 alleles are hypersensitive to ABA, illustrating the biological relevance of the ESCRT pathway for the modulation of ABA signaling. In addition, fyve1 mutants are impaired in the targeting of ABA receptors for vacuolar degradation, leading to increased accumulation of PYL4 and an enhanced response to ABA. Pharmacological and genetic approaches revealed a dynamic turnover of ABA receptors from the plasma membrane to the endosomal/vacuolar degradation pathway, which was mediated by FYVE1 and was dependent on RSL1. This process involves clathrin-mediated endocytosis and trafficking of PYL4 through the ESCRT pathway, which helps to regulate the turnover of ABA receptors and attenuate ABA signaling.

  10. Transcriptional regulation of 9-cis-epoxycarotenoid dioxygenase (NCED) gene by putrescine accumulation positively modulates ABA synthesis and drought tolerance in Lotus tenuis plants.

    PubMed

    Espasandin, Fabiana D; Maiale, Santiago J; Calzadilla, Pablo; Ruiz, Oscar A; Sansberro, Pedro A

    2014-03-01

    The accumulation of putrescine (Put) and increased arginine decarboxylase (ADC, EC 4.1.1.19) activity levels in response to osmotic stress has been reported; however, the biological meaning of this increase remains unclear. To obtain new insights into these questions, we studied the drought response of a transgenic Lotus tenuis line that expresses the oat ADC gene, which is driven by the stress-inducible pRD29A promoter. This line contains high levels of Put with no changes in spermidine and spermine contents, even under water deficits. Our results indicate that the biochemical and morphological responses to dehydration correlate with the Put level and provide evidence that Put controls the ABA content in response to drought by modulating ABA biosynthesis at the transcriptional level.

  11. Are diurnal patterns of stomatal movement the result of alternating metabolism of endogenous guard cell ABA and accumulation of ABA delivered to the apoplast around guard cells by transpiration?

    PubMed

    Tallman, Gary

    2004-09-01

    Abscisic acid (ABA) prevents opening of closed stomata and causes open stomata to close. A dual-source model is proposed linking ABA to diurnal stomatal movements. Darkness would favour guard cell biosynthesis of endogenous ABA and disfavour ABA catabolism. At first light, xanthophyll cycling, isomerization of ABA precursors, and activation of a cytochrome P450 mono-oxygenase (CytP450) would deplete endogenous guard cell ABA. The NADPH-requiring CytP450 would be activated by elevated O2 and reduced CO2 concentrations resulting from mesophyll photosynthesis. An increased O2-to-CO2 ratio would limit the Calvin cycle in guard cells, diverting NADPH produced by photosynthetic electron transport to the cytosol where, along with elevated O2, it would activate CytP450. Depletion of endogenous ABA would liberate guard cells to extrude protons and accumulate the ions and water needed to increase guard cell turgor and open stomata. By midday, stomata would be regulated by steady-state concentrations of ABA delivered to the apoplast around guard cells by transpiration. In temperate conditions, ABA would reach concentrations high enough to trigger ion efflux from guard cells, but too low to defeat the accumulation of sugars used to maintain opening. In dry conditions, ABA would reach effective concentrations by midday, high enough to trigger ion efflux and inhibit sugar uptake, reducing apertures for the rest of the day. At sunset, conditions would again favour biosynthesis and disfavour catabolism of endogenous guard cell ABA. The model can be used to reconcile proposed cellular mechanisms for guard cell signal transduction with patterns of stomatal movements in leaves.

  12. An ABA-responsive DRE-binding protein gene from Setaria italica, SiARDP, the target gene of SiAREB, plays a critical role under drought stress.

    PubMed

    Li, Cong; Yue, Jing; Wu, Xiaowei; Xu, Cong; Yu, Jingjuan

    2014-10-01

    The DREB (dehydration-responsive element binding)-type transcription factors regulate the expression of stress-inducible genes by binding the DRE/CRT cis-elements in promoter regions. The upstream transcription factors that regulate the transcription of DREB transcription factors have not been clearly defined, although the function of DREB transcription factors in abiotic stress is known. In this study, an abscisic acid (ABA)-responsive DREB-binding protein gene (SiARDP) was cloned from foxtail millet (Setaria italica). The transcript level of SiARDP increased not only after drought, high salt, and low temperature stresses, but also after an ABA treatment in foxtail millet seedlings. Two ABA-responsive elements (ABRE1: ACGTGTC; ABRE2: ACGTGGC) exist in the promoter of SiARDP. Further analyses showed that two ABA-responsive element binding (AREB)-type transcription factors, SiAREB1 and SiAREB2, could physically bind to the ABRE core element in vitro and in vivo. The constitutive expression of SiARDP in Arabidopsis thaliana enhanced drought and salt tolerance during seed germination and seedling development, and overexpression of SiARDP in foxtail millet improved drought tolerance. The expression levels of target genes of SiARDP were upregulated in transgenic Arabidopsis and foxtail millet. These results reveal that SiARDP, one of the target genes of SiAREB, is involved in ABA-dependent signal pathways and plays a critical role in the abiotic stress response in plants.

  13. Identification and functional expression of the pepper RING type E3 ligase, CaDTR1, involved in drought stress tolerance via ABA-mediated signalling

    PubMed Central

    Joo, Hyunhee; Lim, Chae Woo; Lee, Sung Chul

    2016-01-01

    Drought negatively affects plant growth and development, thereby leading to loss of crop productivity. Several plant E3 ubiquitin ligases act as positive or negative regulators of abscisic acid (ABA) and thus play important roles in the drought stress response. Here, we show that the C3HC4-type RING finger E3 ligase, CaDTR1, regulates the drought stress response via ABA-mediated signalling. CaDTR1 contains an amino-terminal RING finger motif and two carboxyl-terminal hydrophobic regions; the RING finger motif functions during attachment of ubiquitins to the target proteins, and the carboxyl-terminal hydrophobic regions function during subcellular localisation. The expression of CaDTR1 was induced by ABA, drought, and NaCl treatments. CaDTR1 localised in the nucleus and displayed in vitro E3 ubiquitin ligase activity. CaDTR1-silenced pepper plants exhibited a drought-sensitive phenotype characterised by high levels of transpirational water loss. On the other hand, CaDTR1-overexpressing (OX) Arabidopsis plants exhibited an ABA-hypersensitive phenotype during the germinative and post-germinative growth stages. Moreover, in contrast to CaDTR1-silenced pepper plants, CaDTR1-OX plants exhibited a drought-tolerant phenotype characterised by low levels of transpirational water loss via increased stomatal closure and high leaf temperatures. Our data indicate that CaDTR1 functions as a positive regulator of the drought stress response via ABA-mediated signalling. PMID:27439598

  14. A Novel RNA-Binding Protein Involves ABA Signaling by Post-transcriptionally Repressing ABI2

    PubMed Central

    Xu, Jianwen; Chen, Yihan; Qian, Luofeng; Mu, Rong; Yuan, Xi; Fang, Huimin; Huang, Xi; Xu, Enshun; Zhang, Hongsheng; Huang, Ji

    2017-01-01

    The Stress Associated RNA-binding protein 1 (SRP1) repressed by ABA, salt and cold encodes a C2C2-type zinc finger protein in Arabidopsis. The knock-out mutation in srp1 reduced the sensitivity of seed to ABA and salt stress during germination and post-germinative growth stages. In contrast, SRP1-overexpressing seedlings were more sensitive to ABA and salt compared to wild type plants. In the presence of ABA, the transcript levels of ABA signaling and germination-related genes including ABI3. ABI5. EM1 and EM6 were less induced in srp1 compared to WT. Interestingly, expression of ABI2 encoding a protein phosphatase 2C protein were significantly up-regulated in srp1 mutants. By in vitro analysis, SRP1 was identified as a novel RNA-binding protein directly binding to 3′UTR of ABI2 mRNA. Moreover, transient expression assay proved the function of SRP1 in reducing the activity of luciferase whose coding sequence was fused with the ABI2 3’UTR. Together, it is suggested that SRP1 is involved in the ABA signaling by post-transcriptionally repressing ABI2 expression in Arabidopsis. PMID:28174577

  15. Fungal endophyte Penicillium janthinellum LK5 improves growth of ABA-deficient tomato under salinity.

    PubMed

    Khan, Abdul Latif; Waqas, Muhammad; Khan, Abdur Rahim; Hussain, Javid; Kang, Sang-Mo; Gilani, Syed Abdullah; Hamayun, Muhammad; Shin, Jae-Ho; Kamran, Muhammad; Al-Harrasi, Ahmed; Yun, Byung-Wook; Adnan, Muhammad; Lee, In-Jung

    2013-11-01

    An endophytic fungus was isolated from the roots of tomato (Solanum lycopersicum Mill) and identified as Penicillium janthinellum LK5. The culture filtrate (CF) of P. janthinellum significantly increased the shoot length of gibberellins (GAs) deficient mutant waito-c and normal Dongjin-beyo rice seedlings as compared to control. The CF of P. janthinellum contained GAs (GA3, GA4, GA7 and GA12). To assess endophyte-growth promoting and stress-tolerance potential, the CF along with the propagules of endophyte was applied to tomato-host and abscisic acid (ABA)-deficient mutant Sitiens plants under sodium chloride (NaCl) induced salinity stress. Sitiens plants had retarded growth under normal and salinity stress however its growth was much improved during P. janthinellum-association. The endophyte inoculation reduced the membrane injury by decreasing lipid peroxidation as compared to non-inoculated control under salinity. Endophyte-associated Sitiens plants have significantly higher catalase, peroxidase and glutathione activities as compared to control. Endophyte-infected host and Sitiens plants had low level of sodium ion toxicity and high calcium contents in its root as compared to control. P. janthinellum LK5 helped the Sitiens plants to synthesis significantly higher ABA and reduced the level of jasmonic acid to modulate stress responses. The results suggest that endophytes-association can resist salinity stress by producing gibberellins and activating defensive mechanisms of host and Sitiens plants to achieve improved growth.

  16. Fruit-specific RNAi-mediated suppression of SlNCED1 increases both lycopene and β-carotene contents in tomato fruit.

    PubMed

    Sun, Liang; Yuan, Bing; Zhang, Mei; Wang, Ling; Cui, Mengmeng; Wang, Qi; Leng, Ping

    2012-05-01

    Abscisic acid (ABA) plays important roles during tomato fruit ripening. To study the regulation of carotenoid biosynthesis by ABA, the SlNCED1 gene encoding 9-cis-epoxycarotenoid dioxygenase (NCED), a key enzyme in the ABA biosynthesis, was suppressed in tomato plants by transformation with an RNA interference (RNAi) construct driven by a fruit-specific E8 promoter. ABA accumulation and SlNCED1 transcript levels in the transgenic fruit were down-regulated to between 20-50% of that in control fruit. This significant reduction in NCED activity led to the carbon that normally channels to free ABA as well as the ABA metabolite accumulation during ripening to be partially blocked. Therefore, this 'backlogged' carbon transformed into the carotenoid pathway in the RNAi lines resulted in increased assimilation and accumulation of upstream compounds in the pathway, chiefly lycopene and β-carotene. Fruit of all RNAi lines displayed deep red coloration compared with the pink colour of control fruit. The decrease in endogenous ABA in these transgenics resulted in an increase in ethylene, by increasing the transcription of genes related to the synthesis of ethylene during ripening. In conclusion, ABA potentially regulated the degree of pigmentation and carotenoid composition during ripening and could control, at least in part, ethylene production and action in climacteric tomato fruit.

  17. ABA- and ethylene-mediated responses in osmotically stressed tomato are regulated by the TSS2 and TOS1 loci.

    PubMed

    Rosado, Abel; Amaya, Iraida; Valpuesta, Victoriano; Cuartero, Jesús; Botella, Miguel A; Borsani, Omar

    2006-01-01

    The study of mutants impaired in the sensitivity or synthesis of abscisic acid (ABA) has become a powerful tool to analyse the interactions occurring between the ABA and ethylene signalling pathways, with potential to change the traditional view of the role of ABA as just being involved in growth inhibition. The tss2 tomato mutant, which is hypersensitive to NaCl and osmotic stress, shows enhanced growth inhibition in the presence of exogenous ABA. The tos1 tomato mutant is also hypersensitive to osmotic stress, but in contrast to tss2, shows decreased sensitivity to ABA. Surprisingly, blocking ethylene signalling suppresses the growth defect of tss2 seedlings on ABA, NaCl, and osmotic stress, but not the osmotic hypersensitivity of tos1. The ethylene production of tss2 seedlings is increased compared with that of control seedlings under osmotic stress. In addition, the tss2 plants are hypersensitive to root growth inhibition by the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC). This suggests that, in addition to ABA regulation, TSS2 acts as a negative regulator of endogenous ethylene accumulation. As previously shown in Arabidopsis, it is shown here that extensive cross-talk occurs between the ABA and ethylene signalling pathways in tomato and that the TSS2 and TOS1 loci appear as regulators of this cross-talk.

  18. Abscisic acid-regulated responses of aba2-1 under osmotic stress: the abscisic acid-inducible antioxidant defence system and reactive oxygen species production.

    PubMed

    Ozfidan, C; Turkan, I; Sekmen, A H; Seckin, B

    2012-03-01

    We investigated the interaction among abscisic acid (ABA), reactive oxygen species (ROS) and antioxidant defence system in the transduction of osmotic stress signalling using Arabidopsis thaliana WT (Columbia ecotype, WT) and an ABA-deficient mutant (aba2-1). For this, 50 μm ABA and osmotic stress, induced with 40% (w/v) polyethylene glycol (PEG8000; -0.7 MPa), were applied to WT and aba2-1 for 6, 12 or 24 h. Time course analysis was undertaken for determination of total/isoenzyme activity 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), NADPH oxidase (NOX; EC 1.6.3.1) activity; scavenging activity of the hydroxyl radical (OH˙), hydrogen peroxide (H(2) O(2) ); endogenous ABA and malondialdehyde (MDA). The highest H(2) O(2) and MDA content was found in PEG-treated groups of both genotypes, but with more in aba2-1. ABA treatment under stress reduced the accumulation of H(2) O(2) and MDA, while it promoted activity of SOD, CAT and APX. APX activity was higher than CAT activity in ABA-treated WT and aba2-1, indicating a protective role of APX rather than CAT during osmotic stress-induced oxidative damage. Treatment with ABA also significantly induced increased NOX activity. Oxidative damage was lower in ABA-treated seedlings of both genotypes, which was associated with greater activity of SOD (Mn-SOD1 and 2 and Fe-SOD isoenzymes), CAT and APX in these seedlings after 24 h of stress. These results suggest that osmotic stress effects were overcome by ABA treatment because of increased SOD, CAT, APX and NOX.

  19. Mycorrhizal and non-mycorrhizal Lactuca sativa plants exhibit contrasting responses to exogenous ABA during drought stress and recovery

    PubMed Central

    Aroca, Ricardo; Vernieri, Paolo; Ruiz-Lozano, Juan Manuel

    2008-01-01

    The arbuscular mycorrhizal (AM) symbiosis enhances plant tolerance to water deficit through the alteration of plant physiology and the expression of plant genes. These changes have been postulated to be caused (among others) by different contents of abscisic acid (ABA) between AM and non-AM plants. However, there are no studies dealing with the effects of exogenous ABA on the expression of stress-related genes and on the physiology of AM plants. The aim of the present study was to evaluate the influence of AM symbiosis and exogenous ABA application on plant development, physiology, and expression of several stress-related genes after both drought and a recovery period. Results show that the application of exogenous ABA had contrasting effects on AM and non-AM plants. Only AM plants fed with exogenous ABA maintained shoot biomass production unaltered by drought stress. The addition of exogenous ABA enhanced considerably the ABA content in shoots of non-AM plants, concomitantly with the expression of the stress marker genes Lsp5cs and Lslea and the gene Lsnced. By contrast, the addition of exogenous ABA decreased the content of ABA in shoots of AM plants and did not produce any further enhancement of the expression of these three genes. AM plants always exhibited higher values of root hydraulic conductivity and reduced transpiration rate under drought stress. From plants subjected to drought, only the AM plants recovered their root hydraulic conductivity completely after the 3 d recovery period. As a whole, the results indicate that AM plants regulate their ABA levels better and faster than non-AM plants, allowing a more adequate balance between leaf transpiration and root water movement during drought and recovery. PMID:18469324

  20. Differential hormonal and gene expression dynamics in two inbred sunflower lines with contrasting dormancy level.

    PubMed

    Roselló, Paula L; Vigliocco, Ana E; Andrade, Andrea M; Riera, Natalí V; Calafat, Mario; Molas, María L; Alemano, Sergio G

    2016-05-01

    Seed germination and dormancy are tightly regulated by hormone metabolism and signaling pathway. We investigated the endogenous content of abscisic acid (ABA), its catabolites, and gibberellins (GAs), as well as the expression level of certain ABA and GAs metabolic and signaling genes in embryo of dry and imbibed cypselas of inbred sunflower (Helianthus annuus L., Asteraceae) lines: B123 (dormant) and B91 (non-dormant). Under our experimental conditions, the expression of RGL2 gene might be related to the ABA peak in B123 line at 3 h of imbibition. Indeed, RGL2 transcripts are absent in dry and early embedded cypselas of the non-dormant line B91. ABA increase was accompanied by a significant ABA-Glucosyl ester (ABA-GE) and phaseic acid (PA) (two ABA catabolites) decrease in B123 line (3 h) which indicates that ABA metabolism seems to be more active in this line, and that it would be involved in the imposition and maintenance of sunflower seed dormancy, as it has been reported for many species. Finally, an increase of bioactive GAs (GA1 and GA3) occurs at 12 h of imbibition in both lines after a decrease in ABA content. This study shows the first report about the RGL2 tissue-specific gene expression in sunflower inbred lines with contrasting dormancy level. Furthermore, our results provide evidence that ABA and GAs content and differential expression of metabolism and signaling genes would be interacting in seed dormancy regulation through a mechanism of action related to embryo itself.

  1. Melatonin promotes seed germination under high salinity by regulating antioxidant systems, ABA and GA₄ interaction in cucumber (Cucumis sativus L.).

    PubMed

    Zhang, Hai-Jun; Zhang, Na; Yang, Rong-Chao; Wang, Li; Sun, Qian-Qian; Li, Dian-Bo; Cao, Yun-Yun; Weeda, Sarah; Zhao, Bing; Ren, Shuxin; Guo, Yang-Dong

    2014-10-01

    Although previous studies have found that melatonin can promote seed germination, the mechanisms involved in perceiving and signaling melatonin remain poorly understood. In this study, it was found that melatonin was synthesized during cucumber seed germination with a peak in melatonin levels occurring 14 hr into germination. This is indicative of a correlation between melatonin synthesis and seed germination. Meanwhile, seeds pretreated with exogenous melatonin (1 μM) showed enhanced germination rates under 150 mM NaCl stress compared to water-pretreated seeds under salinity stress. There are two apparent mechanisms by which melatonin alleviated salinity-induced inhibition of seed germination. Exogenous melatonin decreased oxidative damage induced by NaCl stress by enhancing gene expression of antioxidants. Under NaCl stress, compared to untreated control, the activities of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) were significantly increased by approximately 1.3-5.0-fold, with a concomitant 1.4-2.0-fold increase of CsCu-ZnSOD, CsFe-ZnSOD, CsCAT, and CsPOD in melatonin-pretreated seeds. Melatonin also alleviated salinity stress by affecting abscisic acid (ABA) and gibberellin acid (GA) biosynthesis and catabolism during seed germination. Compared to NaCl treatment, melatonin significantly up-regulated ABA catabolism genes (e.g., CsCYP707A1 and CsCYP707A2, 3.5 and 105-fold higher than NaCl treatment at 16 hr, respectively) and down-regulated ABA biosynthesis genes (e.g., CsNECD2, 0.29-fold of CK2 at 16 hr), resulting in a rapid decrease of ABA content during the early stage of germination. At the same time, melatonin positively up-regulated GA biosynthesis genes (e.g., GA20ox and GA3ox, 2.3 and 3.9-fold higher than NaCl treatment at 0 and 12 hr, respectively), contributing to a significant increase of GA (especially GA4) content. In this study, we provide new evidence suggesting that melatonin alleviates the

  2. Increased CSF levels of endorphines in chronic psychosis.

    PubMed

    Terenius, L; Wahlström, A; Lindström, L; Widerlöv, E

    1976-10-01

    The levels of two endorphines, endogenously occurring morphinomimetic peptides, were measured in serial samples of CSF from seven psychiatric patients. Four cases with chronic schizophrenia were studied before and after treatment with the antipsychotic agent clozapine (Leponex). Supernormal fraction II levels were found on at least one sampling occasion in each patient. Two patients, who responded well to clozapine treatment, showed a clear-cut drop in fraction II levels, whereas two patients showed increased levels which paralleled a deterioration of the schizophrenic symptoms. Three manic-depressive cases showed abnormally high levels of endorphine fraction I in the manic phase which declined during normal or depressed phases. Levels of fraction II varied in a less consistent manner and appeared to be at maximum during the apparently normal phases. Although preliminary, the data indicate that endorphines may reach supernormal levels in patients with chronic psychoses.

  3. Increases in serum estrogen levels during major illness are caused by increased peripheral aromatization.

    PubMed

    Spratt, Daniel I; Morton, Jeremy R; Kramer, Robert S; Mayo, Sara W; Longcope, Christopher; Vary, Calvin P H

    2006-09-01

    Although serum testosterone levels decrease acutely in critically ill patients, estrogen levels rise. We hypothesized that increased rates of aromatization of androgens to estrogens underlie the increase in serum estrogen levels. Eleven men and three women (age 42-69 yr) were prospectively studied before and again after elective coronary artery bypass graft surgery (CABG). Each patient received priming doses of [(14)C]androgen and [(3)H]estrogen that were immediately followed by peripheral infusions for 210 min. Eight men and three women received androstenedione (A(4))/estrone (E(1)) and three men received testosterone (T)/estradiol (E(2)). Adipose tissue biopsies were obtained in another six men before and after CABG to evaluate levels of P450 aromatase mRNA. Serum T levels decreased postoperatively in all 17 men (P < 0.001), whereas E(1) levels rose (P = 0.004), with a trend toward a rise in E(2) (P = 0.23). Peripheral aromatization rates of androgens to estrogens rose markedly in all 14 patients (P < 0.0001). Estrogen clearance rates rose (P < 0.002). Mean serum A(4) levels increased slightly postoperatively (P = 0.04), although no increase in A(4) production rates (PRs) was observed. T PRs decreased in two of three men, whereas clearance rates increased in all three. Adipose tissue P450 aromatase mRNA content increased postoperatively (P < 0.001). We conclude that the primary cause of increased estrogen levels in acute illness is increased aromatase P450 gene expression, resulting in enhanced aromatization of androgens to estrogens, a previously undescribed endocrine response to acute illness. Both increased T clearance and decreased T production contribute to decreased serum T levels. Animal studies suggest that these opposing changes in circulating estrogen and androgen levels may be important to reduce morbidity and mortality in critical illness.

  4. Hyperglycemia may determine fibrinopeptide A plasma level increase in humans.

    PubMed

    Ceriello, A; Giugliano, D; Quatraro, A; Dello Russo, P; Marchi, E; Torella, R

    1989-12-01

    The effects of hyperglycemia on plasma fibrinopeptide A (FPA) levels in normal subjects are reported. An increase of FPA concentration parallel to sustained hyperglycemia was observed; when the glycemia returned to basal values, FPA showed values in normal range. Heparin infusion was able to significantly decrease the hyperglycemia-induced augment of FPA levels. Isovolumic-isotonic NaCl solution infusion produced a slight (NS) increase in FPA levels; however, mild hyperglycemia, achieved by glucagon, was also able to produce a significant increase in FPA concentration. These data demonstrate the direct role of hyperglycemia in conditioning FPA level, and suggest that hyperglycemia, by itself, is a sufficient stimulus to produce thrombin activation in humans.

  5. The cotton WRKY transcription factor GhWRKY17 functions in drought and salt stress in transgenic Nicotiana benthamiana through ABA signaling and the modulation of reactive oxygen species production.

    PubMed

    Yan, Huiru; Jia, Haihong; Chen, Xiaobo; Hao, Lili; An, Hailong; Guo, Xingqi

    2014-12-01

    Drought and high salinity are two major environmental factors that significantly limit the productivity of agricultural crops worldwide. WRKY transcription factors play essential roles in the adaptation of plants to abiotic stresses. However, WRKY genes involved in drought and salt tolerance in cotton (Gossypium hirsutum) are largely unknown. Here, a group IId WRKY gene, GhWRKY17, was isolated and characterized. GhWRKY17 was found to be induced after exposure to drought, salt, H2O2 and ABA. The constitutive expression of GhWRKY17 in Nicotiana benthamiana remarkably reduced plant tolerance to drought and salt stress, as determined through physiological analyses of the germination rate, root growth, survival rate, leaf water loss and Chl content. GhWRKY17 transgenic plants were observed to be more sensitive to ABA-mediated seed germination and root growth. However, overexpressing GhWRKY17 in N. benthamiana impaired ABA-induced stomatal closure. Furthermore, we found that GhWRKY17 modulated the increased sensitivity of plants to drought by reducing the level of ABA, and transcript levels of ABA-inducible genes, including AREB, DREB, NCED, ERD and LEA, were clearly repressed under drought and salt stress conditions. Consistent with the accumulation of reactive oxygen species (ROS), reduced proline contents and enzyme activities, elevated electrolyte leakage and malondialdehyde, and lower expression of ROS-scavenging genes, including APX, CAT and SOD, the GhWRKY17 transgenic plants exhibited reduced tolerance to oxidative stress compared with wild-type plants. These results therefore indicate that GhWRKY17 responds to drought and salt stress through ABA signaling and the regulation of cellular ROS production in plants.

  6. Interplay between ABA and phospholipases A(2) and D in the response of citrus fruit to postharvest dehydration.

    PubMed

    Romero, Paco; Gandía, Mónica; Alférez, Fernando

    2013-09-01

    The interplay between abscisic acid (ABA) and phospholipases A2 and D (PLA2 and PLD) in the response of citrus fruit to water stress was investigated during postharvest by using an ABA-deficient mutant from 'Navelate' orange named 'Pinalate'. Fruit from both varieties harvested at two different maturation stages (mature-green and full-mature) were subjected to prolonged water loss inducing stem-end rind breakdown (SERB) in full-mature fruit. Treatment with PLA2 inhibitor aristolochic acid (AT) and PLD inhibitor lysophosphatidylethanolamine (LPE) reduced the disorder in both varieties, suggesting that phospholipid metabolism is involved in citrus peel quality. Expression of CsPLDα and CsPLDβ, and CssPLA2α and CssPLA2β was studied by real-time RT-PCR during water stress and in response to ABA. CsPLDα expression increased in mature-green fruit from 'Navelate' but not in 'Pinalate' and ABA did not counteract this effect. ABA enhanced repression of CsPLDα in full-mature fruit. CsPLDβ gene expression decreased in mature-green 'Pinalate', remained unchanged in 'Navelate' and was induced in full-mature fruit from both varieties. CssPLA2α expression increased in mature-green fruit from both varieties whereas in full-mature fruit only increased in 'Navelate'. CssPLA2β expression increased in mature-green flavedo from both varieties, but in full-mature fruit remained steady in 'Navelate' and barely increased in 'Pinalate' fruit. ABA reduced expression in both after prolonged storage. Responsiveness to ABA increased with maturation. Our results show interplay between PLA2 and PLD and suggest that ABA action is upstream phospholipase activation. Response to ABA during water stress in citrus is regulated during fruit maturation and involves membrane phospholipid degradation.

  7. Brassinosteroids modulate ABA-induced stomatal closure in Arabidopsis

    PubMed Central

    Ha, Yunmi; Shang, Yun; Nam, Kyoung Hee

    2016-01-01

    Stomatal movement in response to water availability is an important physiological process in the survival of land plants. The plant hormone abscisic acid (ABA) and brassinosteroids (BRs) regulate stomatal closure. The physiological functions of ABA and BRs, including germination, cell elongation and stomatal movement, are generally known to be antagonistic. Here, we investigated how BRs affect stomatal movement alone and in combination with ABA. We demonstrate that brassinoslide (BL), the most active BR, promotes stomatal closure in an ABA-independent manner. Interestingly, BL also inhibited ABA-induced stomatal closure when a high concentration of BL was added to ABA. Furthermore, we found that the induction of some genes for reactive oxygen species (ROS) generation by ABA (AtrbohD, NIA1 and NIA2) and subsequent ROS production were repressed by BL treatment. The BR signaling mutant bri1-301 failed to inhibit ABA-induced stomatal closure upon BL treatment. However, BRI1-overexpressing transgenic plants were hypersensitive to ABA during stomatal closure, and BL reversed ABA-induced stomatal closure more completely than in wild type plants. Taken together, these results suggest that BRs can positively and negatively modulate ABA-induced stomatal closure. Therefore, interactions between ABA and BR signaling are important for the regulation of stomatal closure. PMID:27856707

  8. Root water potential integrates discrete soil physical properties to influence ABA signalling during partial rootzone drying.

    PubMed

    Dodd, Ian C; Egea, Gregorio; Watts, Chris W; Whalley, W Richard

    2010-08-01

    To investigate the influence of different growing substrates (two mineral, two organic) on root xylem ABA concentration ([ABA](root)) and the contribution of the drying root system to total sap flow during partial rootzone drying (PRD), sunflower (Helianthus annuus L.) shoots were grafted onto the root systems of two plants grown in separate pots. Sap flow through each hypocotyl was measured below the graft union when one pot ('wet') was watered and other ('dry') was not. Each substrate gave unique relationships between dry pot matric potential (Psi(soil)), volumetric water content ((v)) or penetrometer resistance (Q) and either the fraction of photoperiod sap flow from roots in drying soil or [ABA](root). However, decreased relative sap flow, and increased [ABA](root), from roots in drying soil varied with root water potential (Psi(root)) more similarly across a range of substrates. The gradient between Psi(soil) and Psi(root) was greater in substrates with high sand or peat proportions, which may have contributed to a more sensitive response of [ABA](root) to Psi(soil) in these substrates. Whole plant transpiration was most closely correlated with the mean Psi(soil) of both pots, and then with detached leaf xylem ABA concentration. Although Psi(root) best predicted decreased relative sap flow, and increased [ABA](root), from roots in drying soil across a range of substrates, the inaccessibility of this variable in field studies requires a better understanding of how measurable soil variables (Psi(soil), (v), Q) affect Psi(root).

  9. PLASTID MOVEMENT IMPAIRED1 mediates ABA sensitivity during germination and implicates ABA in light-mediated Chloroplast movements.

    PubMed

    Rojas-Pierce, Marcela; Whippo, Craig W; Davis, Phillip A; Hangarter, Roger P; Springer, Patricia S

    2014-10-01

    The plant hormone abscisic acid (ABA) controls many aspects of plant growth and development, including seed development, germination and responses to water-deficit stress. A complex ABA signaling network integrates environmental signals including water availability and light intensity and quality to fine-tune the response to a changing environment. To further define the regulatory pathways that control water-deficit and ABA responses, we carried out a gene-trap tagging screen for water-deficit-regulated genes in Arabidopsis thaliana. This screen identified PLASTID MOVEMENT IMPAIRED1 (PMI1), a gene involved in blue-light-induced chloroplast movement, as functioning in ABA-response pathways. We provide evidence that PMI1 is involved in the regulation of seed germination by ABA, acting upstream of the intersection between ABA and low-glucose signaling pathways. Furthermore, PMI1 participates in the regulation of ABA accumulation during periods of water deficit at the seedling stage. The combined phenotypes of pmi1 mutants in chloroplast movement and ABA responses indicate that ABA signaling may modulate chloroplast motility. This result was further supported by the detection of altered chloroplast movements in the ABA mutants aba1-6, aba2-1 and abi1-1.

  10. Increased interleukin-13 levels in patients with chronic heart failure.

    PubMed

    Nishimura, Yuki; Inoue, Teruo; Nitto, Takeaki; Morooka, Toshifumi; Node, Koichi

    2009-01-24

    A great number of basic and clinical studies have demonstrated that inflammatory cytokines play an important role in development and progress of heart failure. However, there is limited information about allergic cytokine interleukin-13 (IL-13). The inflammatory responses mediated by allergic cytokines can cause significant morbidity and mortality when they become chronic. Therefore, we elucidated the role of IL-13 in the pathophysiology of chronic heart failure. We measured plasma IL-13 levels by enzyme-linked immunosorbent assay in 110 patients with chronic heart failure and 20 control subjects. Plasma IL-13 levels were increased in heart failure patients, compared with the controls, in association with NYHA functional class. In addition, IL-13 levels were correlated positively with plasma levels of brain natriuretic peptide and C-reactive protein, and negatively with left ventricular ejection fraction. Plasma IL-13 levels may be useful for evaluating disease severity in chronic heart failure.

  11. Function of the HD-Zip I gene Oshox22 in ABA-mediated drought and salt tolerances in rice.

    PubMed

    Zhang, Shuxin; Haider, Imran; Kohlen, Wouter; Jiang, Li; Bouwmeester, Harro; Meijer, Annemarie H; Schluepmann, Henriette; Liu, Chun-Ming; Ouwerkerk, Pieter B F

    2012-12-01

    Oshox22 belongs to the homeodomain-leucine zipper (HD-Zip) family I of transcription factors, most of which have unknown functions. Here we show that the expression of Oshox22 is strongly induced by salt stress, abscisic acid (ABA), and polyethylene glycol treatment (PEG), and weakly by cold stress. Trans-activation assays in yeast and transient expression analyses in rice protoplasts demonstrated that Oshox22 is able to bind the CAAT(G/C)ATTG element and acts as a transcriptional activator that requires both the HD and Zip domains. Rice plants homozygous for a T-DNA insertion in the promoter region of Oshox22 showed reduced Oshox22 expression and ABA content, decreased sensitivity to ABA, and enhanced tolerance to drought and salt stresses at the seedling stage. In contrast, transgenic rice over-expressing Oshox22 showed increased sensitivity to ABA, increased ABA content, and decreased drought and salt tolerances. Based on these results, we conclude that Oshox22 affects ABA biosynthesis and regulates drought and salt responses through ABA-mediated signal transduction pathways.

  12. Increased brain nitric oxide levels following ethanol administration.

    PubMed

    Finnerty, Niall; O'Riordan, Saidhbhe L; Klamer, Daniel; Lowry, John; Pålsson, Erik

    2015-05-01

    Nitric oxide is a ubiquitous messenger molecule, which at elevated concentrations has been implicated in the pathogenesis of several neurological disorders. Its role in oxidative stress, attributed in particular to the formation of peroxynitrite, proceeds through its high affinity for the superoxide radical. Alcoholism has recently been associated with the induction of oxidative stress, which is generally defined as a shift in equilibrium between pro-oxidant and anti-oxidant species in the direction of the former. Furthermore, its primary metabolite acetaldehyde, has been extensively associated with oxidative damage related toxic effects following alcohol ingestion. The principal objective of this study was the application of long term in vivo electrochemistry (LIVE) to investigate the effect of ethanol (0.125, 0.5 and 2.0 g kg(-1)) and acetaldehyde (12.5, 50 and 200 mg kg(-1)) on NO levels in the nucleus accumbens of freely moving rats. Systemic administrations of ethanol and acetaldehyde resulted in a dose-dependent increases in NO levels, albeit with very differing time courses. Subsequent to this the effect on accumbal NO levels, of subjecting the animal to different drug combinations, was also elucidated. The nitric oxide synthase inhibitor L-NAME (20 mg kg(-1)) and acetaldehyde sequestering agent D-penicillamine (50 mg kg(-1)) both attenuated the increase in NO levels following ethanol (1 g kg(-1)) administration. Conversely, the alcohol dehydrogenase inhibitor 4-methylpyrazole (25 mg kg(-1)) and catalase inhibitor sodium azide (10 mg kg(-1)) potentiated the increase in NO levels following ethanol administration. Finally, dual inhibition of aldehyde dehydrogenase and catalase by cyanamide (25 mg kg(-1)) caused an attenuation of ethanol effects on NO levels. Taken together these data highlight a robust increase in brain NO levels following systemic alcohol administration which is dependent on NO synthase activity and may involve both alcohol- and acetaldehyde

  13. The effect of light on ABA catabolism in excised seedlings of Phaseolus vulgaris L. cv. top-crop

    SciTech Connect

    Cowan, A.K.; Myemane, D.M. )

    1990-05-01

    Studies on the influence of light quality on ABA catabolism have implicated the involvement of phytochrome in this process. Detailed experiments were therefore carried out to determine whether light could be a factor involved in the regulation of ABA catabolism in higher plants. Excised, etiolated seedlings of Phaseolus vulgaris (4.5g fr. wt.) were supplied with (R,S,)-(2-{sup 14}C)-ABA (5.0 kBq) and exposed to various combinations of red (37 {mu}mol m{sup {minus}2} s{sup {minus}1}) and far-red (23 {mu}mol m{sup {minus}2} s{sup {minus}1}) light. Following light treatments seedlings were returned to darkness for the remainder of the 20 h incubation period. Far-red light illumination stimulated ABA catabolism whereas red light had no significant effect on this process. Kinetic studies and analysis of water-soluble conjugates revealed that far-red light treatment enhanced the sequestration of ABA and its acidic products. The apparent inhibition of ABA catabolism by red light was relieved, if red light irradiation was followed immediately by a dose of far-red light. Thus, these data indicate that ABA catabolism might be mediated by phytochrome and that control is exerted at the level of conjugation rather than oxidation.

  14. Evolutionary Conservation of ABA Signaling for Stomatal Closure in Ferns.

    PubMed

    Cai, Shengguan; Chen, Guang; Wang, Yuanyuan; Huang, Yuqing; Marchant, Blaine; Wang, Yizhou; Yang, Qian; Dai, Fei; Hills, Adrian; Franks, Peter J; Nevo, Eviatar; Soltis, Doug; Soltis, Pamela; Sessa, Emily; Wolf, Paul G; Xue, Dawei; Zhang, Guoping; Pogson, Barry J; Blatt, Mike R; Chen, Zhong-Hua

    2017-02-23

    ABA-driven stomatal regulation reportedly evolved after the divergence of ferns, during the early evolution of seed plants approximately 360 Mya. This hypothesis is based on the observation that the stomata of certain fern species are unresponsive to ABA, but exhibit passive hydraulic control. However, ABA-induced stomatal closure was detected in some mosses and lycophytes. Here, we observed that a number of ABA signaling and membrane transporter protein families diversified over the evolutionary history of land plants. The aquatic ferns Azolla filiculoides and Salvinia cucullata have representatives of 23 families of proteins orthologous to those of Arabidopsis thaliana and all other land plant species studied. Phylogenetic analysis of the key ABA signaling proteins indicates an evolutionarily conserved stomatal response to ABA. Moreover, comparative transcriptomic analysis has identified a suite of ABA responsive genes that differentially expressed in a terrestrial fern species, Polystichum proliferum. These genes encode proteins associated with ABA biosynthesis, transport, reception, transcription, signaling, and ion and sugar transport, which fit the general ABA signaling pathway constructed from Arabidopsis thaliana and Hordeum vulgare. The retention of these key ABA-responsive genes could have had a profound effect on the adaptation of ferns to dry conditions. Furthermore, stomatal assays have shown the primary evidence for ABA-induced closure of stomata in two terrestrial fern species P. proliferum and Nephrolepis exaltata. In summary, we report new molecular and physiological evidence for the presence of active stomatal control in ferns.

  15. Increased isoprostane levels in oleic acid-induced lung injury

    SciTech Connect

    Ono, Koichi; Koizumi, Tomonobu; Tsushima, Kenji; Yoshikawa, Sumiko; Yokoyama, Toshiki; Nakagawa, Rikimaru; Obata, Toru

    2009-10-16

    The present study was performed to examine a role of oxidative stress in oleic acid-induced lung injury model. Fifteen anesthetized sheep were ventilated and instrumented with a lung lymph fistula and vascular catheters for blood gas analysis and measurement of isoprostanes (8-epi prostaglandin F2{alpha}). Following stable baseline measurements, oleic acid (0.08 ml/kg) was administered and observed 4 h. Isoprostane was measured by gas chromatography mass spectrometry with the isotope dilution method. Isoprostane levels in plasma and lung lymph were significantly increased 2 h after oleic acid administration and then decreased at 4 h. The percent increases in isoprostane levels in plasma and lung lymph at 2 h were significantly correlated with deteriorated oxygenation at the same time point, respectively. These findings suggest that oxidative stress is involved in the pathogenesis of the pulmonary fat embolism-induced acute lung injury model in sheep and that the increase relates with the deteriorated oxygenation.

  16. A Glycine soja ABA-responsive receptor-like cytoplasmic kinase, GsRLCK, positively controls plant tolerance to salt and drought stresses.

    PubMed

    Sun, XiaoLi; Sun, Mingzhe; Luo, Xiao; Ding, XiaoDong; Ji, Wei; Cai, Hua; Bai, Xi; Liu, XiaoFei; Zhu, YanMing

    2013-06-01

    Receptor such as protein kinases are proposed to work as sensors to initiate signaling cascades in higher plants. However, little is known about the precise functions of receptor such as protein kinases in abiotic stress response in plants, especially in wild soybean. Here, we focused on characterization of the biological functions of a receptor-like cytoplasmic serine/threonine protein kinase gene, GsRLCK, which was previously identified as a putative salt-alkali stress-related gene from the transcriptome profiles of Glycine soja. Bioinformatic analysis showed that GsRLCK protein contained a conserved kinase catalytic domain and two transmembrane domains at the N-terminus, but no typical extracellular domain. Consistently, GsRLCK-eGFP fusion protein was observed on the plasma membrane, but eGFP alone was distributing throughout the cytoplasm in onion epidermal cells. Quantitative real-time PCR analysis revealed the induced expression of GsRLCK by ABA, salt, alkali, and drought stresses. However, the expression levels of GsRLCK seemed to be similar in different tissues, except soybean pod. Phenotypic assays demonstrated that GsRLCK overexpression decreased ABA sensitivity and altered expression levels of ABA-responsive genes. Furthermore, we also found that GsRLCK conferred increased tolerance to salt and drought stresses and increased expression levels of a handful of stress-responsive genes, when overexpressing in Arabidopsis. In a word, we gave exact evidence that GsRLCK was a novel receptor-like cytoplasmic protein kinase and played a crucial role in plant responses to ABA, salt, and drought stresses.

  17. Endozepine-4 levels are increased in hepatic coma

    PubMed Central

    Malaguarnera, Giulia; Vacante, Marco; Drago, Filippo; Bertino, Gaetano; Motta, Massimo; Giordano, Maria; Malaguarnera, Michele

    2015-01-01

    AIM: To evaluate the serum levels of endozepine-4, their relation with ammonia serum levels, the grading of coma and the severity of cirrhosis, in patients with hepatic coma. METHODS: In this study we included 20 subjects with Hepatic coma, 20 subjects with minimal hepatic encephalopathy (MHE) and 20 subjects control. All subjects underwent blood analysis, Child Pugh and Model for End - stage liver disease (MELD) assessment, endozepine-4 analysis. RESULTS: Subjects with hepatic coma showed significant difference in endozepine-4 (P < 0.001) and NH3 levels (P < 0.001) compared both to MHE and controls patients. Between NH3 and endozepine-4 we observed a significant correlation (P = 0.009; Pearson correlation 0.570). There was a significant correlation between endozepine-4 and MELD (P = 0.017; Pearson correlation = 0.529). In our study blood ammonia concentration was noted to be raised in patients with hepatic coma, with the highest ammonia levels being found in those who were comatose. We also found a high correlation between endozepine-4 and ammonia (P < 0.001). In patients with grade IV hepatic coma, endozepine levels were significantly higher compared to other groups. CONCLUSION: This study suggests that an increased level of endozepine in subjects with higher levels of MELD was observed. In conclusion, data concerning involvement of the GABA-ergic system in HE coma could be explained by stage-specific alterations. PMID:26290636

  18. Increasing carbonmonoxide blood levels in Bangkok bus drivers

    SciTech Connect

    Saenghirunvattana, S.; Wananukul, W.; Mokkhavesa, C.; Opasi, N.

    1995-05-01

    In order to study the effects of air pollution in Bangkok, 31 bus drivers were examined and blood was drawn for measurement of carboxyhemoglobin (COHb) prior to and after work. The COHb level before work was 2.19{+-}2.46% (range 0.7.18). It had increased after work to 5.26{+-}2.52% (range 0-10.4) (p<0.001). Twenty-one drivers complained of chronic headaches, myalgia, and eye irritation during working hours. The COHb level was not statistically different between smokers and nonsmokers.

  19. Methamphetamine increases basal ganglia iron to levels observed in aging.

    PubMed

    Melega, William P; Laćan, Goran; Harvey, Dennis C; Way, Baldwin M

    2007-10-29

    Increases in basal ganglia iron are well documented for neurodegenerative diseases but have not been associated with methamphetamine (METH). In this study, vervet monkeys that received two doses of METH (2 mg/kg, intramuscularly, 6 h apart) showed at 1 month, iron increases in substantia nigra pars reticulata and globus pallidus, with concurrent increases of ferritin-immunoreactivity and decreases of tyrosine hydroxylase-immunoreactivity in substantia nigra. At 1.5 years, substantia nigra tyrosine hydroxylase-immunoreactivity had recovered while iron and ferritin-immunoreactivity increases persisted. Globus pallidus and substantia nigra iron levels of the adult METH-exposed animals (age 5-9 years) were now comparable with those of drug-naive, aged animals (19-22 years), suggesting an aging-related condition that might render those regions more vulnerable to oxidative stress.

  20. The Role of Endogenous Strigolactones and Their Interaction with ABA during the Infection Process of the Parasitic Weed Phelipanche ramosa in Tomato Plants

    PubMed Central

    Cheng, Xi; Floková, Kristýna; Bouwmeester, Harro; Ruyter-Spira, Carolien

    2017-01-01

    The root parasitic plant species Phelipanche ramosa, branched broomrape, causes severe damage to economically important crops such as tomato. Its seed germination is triggered by host-derived signals upon which it invades the host root. In tomato, strigolactones (SLs) are the main germination stimulants for P. ramosa. Therefore, the development of low SL-producing lines may be an approach to combat the parasitic weed problem. However, since SLs are also a plant hormone controlling many aspects of plant development, SL deficiency may also have an effect on post-germination stages of the infection process, during the parasite-host interaction. In this study, we show that SL-deficient tomato plants (Solanum lycopersicum; SlCCD8 RNAi lines), infected with pre-germinated P. ramosa seeds, display an increased infection level and faster development of the parasite, which suggests a positive role for SLs in the host defense against parasitic plant invasion. Furthermore, we show that SL-deficient tomato plants lose their characteristic SL-deficient phenotype during an infection with P. ramosa through a reduction in the number of internodes and the number and length of secondary branches. Infection with P. ramosa resulted in increased levels of abscisic acid (ABA) in the leaves and roots of both wild type and SL-deficient lines. Upon parasite infection, the level of the conjugate ABA-glucose ester (ABA-GE) also increased in leaves of both wild type and SL-deficient lines and in roots of one SL-deficient line. The uninfected SL-deficient lines had a higher leaf ABA-GE level than the wild type. Despite the high levels of ABA, stomatal aperture and water loss rate were not affected by parasite infection in the SL-deficient line, while in wild type tomato stomatal aperture and water loss increased upon infection. Future studies are needed to further underpin the role that SLs play in the interaction of hosts with parasitic plants and which other plant hormones interact with the

  1. Sap fluxes from different parts of the rootzone modulate xylem ABA concentration during partial rootzone drying and re-wetting.

    PubMed

    Pérez-Pérez, J G; Dodd, I C

    2015-04-01

    Previous studies with partial rootzone drying (PRD) irrigation demonstrated that alternating the wet and dry parts of the rootzone (PRD-Alternated) increased leaf xylem ABA concentration ([X-ABA]leaf) compared with maintaining the same wet and dry parts of the rootzone (PRD-Fixed). To determine the relative contributions of different parts of the rootzone to this ABA signal, [X-ABA]leaf of potted, split-root tomato (Solanum lycopersicum) plants was modelled by quantifying the proportional water uptake from different soil compartments, and [X-ABA]leaf responses to the entire pot soil-water content (θpot). Continuously measuring soil-moisture depletion by, or sap fluxes from, different parts of the root system revealed that water uptake rapidly declined (within hours) after withholding water from part of the rootzone, but was rapidly restored (within minutes) upon re-watering. Two hours after re-watering part of the rootzone, [X-ABA]leaf was equally well predicted according to θpot alone and by accounting for the proportional water uptake from different parts of the rootzone. Six hours after re-watering part of the rootzone, water uptake by roots in drying soil was minimal and, instead, occurred mainly from the newly irrigated part of the rootzone, thus [X-ABA]leaf was best predicted by accounting for the proportional water uptake from different parts of the rootzone. Contrary to previous results, alternating the wet and dry parts of the rootzone did not enhance [X-ABA]leaf compared with PRD-Fixed irrigation. Further work is required to establish whether altered root-to-shoot ABA signalling contributes to the improved yields of crops grown with alternate, rather than fixed, PRD.

  2. ABA Inducible Rice Protein Phosphatase 2C Confers ABA Insensitivity and Abiotic Stress Tolerance in Arabidopsis

    PubMed Central

    Singh, Amarjeet; Jha, Saroj K.; Bagri, Jayram; Pandey, Girdhar K.

    2015-01-01

    Arabidopsis PP2C belonging to group A have been extensively worked out and known to negatively regulate ABA signaling. However, rice (Oryza sativa) orthologs of Arabidopsis group A PP2C are scarcely characterized functionally. We have identified a group A PP2C from rice (OsPP108), which is highly inducible under ABA, salt and drought stresses and localized predominantly in the nucleus. Genetic analysis revealed that Arabidopsis plants overexpressing OsPP108 are highly insensitive to ABA and tolerant to high salt and mannitol stresses during seed germination, root growth and overall seedling growth. At adult stage, OsPP108 overexpression leads to high tolerance to salt, mannitol and drought stresses with far better physiological parameters such as water loss, fresh weight, chlorophyll content and photosynthetic potential (Fv/Fm) in transgenic Arabidopsis plants. Expression profile of various stress marker genes in OsPP108 overexpressing plants revealed interplay of ABA dependent and independent pathway for abiotic stress tolerance. Overall, this study has identified a potential rice group A PP2C, which regulates ABA signaling negatively and abiotic stress signaling positively. Transgenic rice plants overexpressing this gene might provide an answer to the problem of low crop yield and productivity during adverse environmental conditions. PMID:25886365

  3. ABA inducible rice protein phosphatase 2C confers ABA insensitivity and abiotic stress tolerance in Arabidopsis.

    PubMed

    Singh, Amarjeet; Jha, Saroj K; Bagri, Jayram; Pandey, Girdhar K

    2015-01-01

    Arabidopsis PP2C belonging to group A have been extensively worked out and known to negatively regulate ABA signaling. However, rice (Oryza sativa) orthologs of Arabidopsis group A PP2C are scarcely characterized functionally. We have identified a group A PP2C from rice (OsPP108), which is highly inducible under ABA, salt and drought stresses and localized predominantly in the nucleus. Genetic analysis revealed that Arabidopsis plants overexpressing OsPP108 are highly insensitive to ABA and tolerant to high salt and mannitol stresses during seed germination, root growth and overall seedling growth. At adult stage, OsPP108 overexpression leads to high tolerance to salt, mannitol and drought stresses with far better physiological parameters such as water loss, fresh weight, chlorophyll content and photosynthetic potential (Fv/Fm) in transgenic Arabidopsis plants. Expression profile of various stress marker genes in OsPP108 overexpressing plants revealed interplay of ABA dependent and independent pathway for abiotic stress tolerance. Overall, this study has identified a potential rice group A PP2C, which regulates ABA signaling negatively and abiotic stress signaling positively. Transgenic rice plants overexpressing this gene might provide an answer to the problem of low crop yield and productivity during adverse environmental conditions.

  4. A Mutant of Arabidopsis with Increased Levels of Stearic Acid.

    PubMed Central

    Lightner, J.; Wu, J.; Browse, J.

    1994-01-01

    A mutation at the fab2 locus of Arabidopsis caused increased levels of stearate in leaves. The increase in leaf stearate in fab2 varied developmentally, and the largest increase occurred in young leaves, where stearate accounted for almost 20% of total leaf fatty acids. The fatty acid composition of leaf lipids isolated from the fab2 mutant showed increased stearate in all the major glycerolipids of both the chloroplast and extrachloroplast membranes. Although the stearate content was increased, the fab2 mutant still contained abundant amounts of 18:1, 18:2, and 18:3 fatty acids. These results are consistent with the expectations for a mutation partially affecting the action of the stromal stearoyl-acyl carrier protein desaturase. Positional analysis indicated that the extra 18:0 is excluded with high specificity from the sn-2 position of both chloroplast and extrachloroplast glycerolipids. Although stearate content was increased in all the major leaf membrane lipids, the amount of increase varied considerably among the different lipids, from a high of 25% of fatty acids in phosphatidylcholine to a low of 2.9% of fatty acids in monogalactosyldiacylglycerol. PMID:12232421

  5. Excess nicotinamide increases plasma serotonin and histamine levels.

    PubMed

    Tian, Yan-Jie; Li, Da; Ma, Qiang; Gu, Xin-Yi; Guo, Ming; Lun, Yong-Zhi; Sun, Wu-Ping; Wang, Xin-Yuan; Cao, Yu; Zhou, Shi-Sheng

    2013-02-25

    Methylation, a methyl group-consuming reaction, plays a key role in the degradation (i.e., inactivation) of monoamine neurotransmitters, including catecholamines, serotonin and histamine. Without labile methyl groups, the methylation-mediated degradation cannot take place. Although high niacin (nicotinic acid and nicotinamide) intake, which is very common nowadays, is known to deplete the body's methyl-group pool, its effect on monoamine-neurotransmitter degradation is not well understood. The aim of this article was to investigate the effect of excess nicotinamide on the levels of plasma serotonin and histamine in healthy subjects. Urine and venous blood samples were collected from nine healthy male volunteers before and after oral loading with 100 mg nicotinamide. Plasma N(1)-methylnicotinamide, urinary N(1)-methyl-2-pyridone-5-carboxamide (2-Py), and plasma betaine levels were measured by using high-performance liquid chromatography (HPLC). Plasma concentrations of choline, serotonin and histamine were measured using commercial kits. The results showed that the plasma N(1)-methylnicotinamide level and the urinary excretion of 2-Py significantly increased after oral loading with 100 mg nicotinamide, which was accompanied with a decrease in the methyl-group donor betaine. Compared with those before nicotinamide load, five-hour postload plasma serotonin and histamine levels significantly increased. These results suggest that excess nicotinamide can disturb monoamine-neurotransmitter metabolism. These findings may be of significance in understanding the etiology of monoamine-related mental diseases, such as schizophrenia and autism (a neurodevelopmental disorder).

  6. Stomatal closure is induced by hydraulic signals and maintained by ABA in drought-stressed grapevine

    PubMed Central

    Tombesi, Sergio; Nardini, Andrea; Frioni, Tommaso; Soccolini, Marta; Zadra, Claudia; Farinelli, Daniela; Poni, Stefano; Palliotti, Alberto

    2015-01-01

    Water saving under drought stress is assured by stomatal closure driven by active (ABA-mediated) and/or passive (hydraulic-mediated) mechanisms. There is currently no comprehensive model nor any general consensus about the actual contribution and relative importance of each of the above factors in modulating stomatal closure in planta. In the present study, we assessed the contribution of passive (hydraulic) vs active (ABA mediated) mechanisms of stomatal closure in V. vinifera plants facing drought stress. Leaf gas exchange decreased progressively to zero during drought, and embolism-induced loss of hydraulic conductance in petioles peaked to ~50% in correspondence with strong daily limitation of stomatal conductance. Foliar ABA significantly increased only after complete stomatal closure had already occurred. Rewatering plants after complete stomatal closure and after foliar ABA reached maximum values did not induced stomatal re-opening, despite embolism recovery and water potential rise. Our data suggest that in grapevine stomatal conductance is primarily regulated by passive hydraulic mechanisms. Foliar ABA apparently limits leaf gas exchange over long-term, also preventing recovery of stomatal aperture upon rewatering, suggesting the occurrence of a mechanism of long-term down-regulation of transpiration to favor embolism repair and preserve water under conditions of fluctuating water availability and repeated drought events. PMID:26207993

  7. Aspergillus fumigatus challenge increases cytokine levels in nasal lavage fluid.

    PubMed

    Stark, H; Roponen, M; Purokivi, M; Randell, J; Tukiainen, H; Hirvonen, M-R

    2006-12-01

    Several studies have shown an association between exposure in moisture-damaged buildings and adverse health effects. There are several indicator microbes of moisture damage, but Aspergillus fumigatus is one of the best-documented molds provoking health problems in different occupational conditions. We assessed whether inhalation of a commercial A. fumigatus solution would affect cytokine levels (tumor necrosis factor [TNF]-alpha, interleukin [IL]-1beta, IL-4, IL-6, interferon [IFN]-gamma) in nasal lavage fluid (NAL) compared with that evoked by placebo challenge. Twenty-seven subjects were studied: 13 had occupational exposure in a moisture-damaged building, 4 were atopic, and 10 were considered as controls. In all the subjects, the IL-1beta levels were increased significantly both at 6 (p = 0.013) and 24 h (p = .005) after the A. fumigatus challenge compared to placebo. In subjects with previous occupational exposure in a moisture-damaged building, IL-4 concentrations were increased significantly both at 6 (p =.046) and 24 h (p =.008) after the A. fumigatus challenge compared with placebo. Furthermore, in the control group, TNF-alpha levels were significantly increased at 6 h after the A. fumigatus challenge compared to placebo (p = .028). Thus, these data show a link between markers of inflammation in NAL and experimental A. fumigatus challenge.

  8. Activation of dimeric ABA receptors elicits guard cell closure, ABA-regulated gene expression, and drought tolerance

    PubMed Central

    Okamoto, Masanori; Peterson, Francis C.; Defries, Andrew; Park, Sang-Youl; Endo, Akira; Nambara, Eiji; Volkman, Brian F.; Cutler, Sean R.

    2013-01-01

    Abscisic acid (ABA) is an essential molecule in plant abiotic stress responses. It binds to soluble pyrabactin resistance1/PYR1-like/regulatory component of ABA receptor receptors and stabilizes them in a conformation that inhibits clade A type II C protein phosphatases; this leads to downstream SnRK2 kinase activation and numerous cellular outputs. We previously described the synthetic naphthalene sulfonamide ABA agonist pyrabactin, which activates seed ABA responses but fails to trigger substantial responses in vegetative tissues in Arabidopsis thaliana. Here we describe quinabactin, a sulfonamide ABA agonist that preferentially activates dimeric ABA receptors and possesses ABA-like potency in vivo. In Arabidopsis, the transcriptional responses induced by quinabactin are highly correlated with those induced by ABA treatments. Quinabactin treatments elicit guard cell closure, suppress water loss, and promote drought tolerance in adult Arabidopsis and soybean plants. The effects of quinabactin are sufficiently similar to those of ABA that it is able to rescue multiple phenotypes observed in the ABA-deficient mutant aba2. Genetic analyses show that quinabactin’s effects in vegetative tissues are primarily mediated by dimeric ABA receptors. A PYL2-quinabactin-HAB1 X-ray crystal structure solved at 1.98-Å resolution shows that quinabactin forms a hydrogen bond with the receptor/PP2C “lock” hydrogen bond network, a structural feature absent in pyrabactin-receptor/PP2C complexes. Our results demonstrate that ABA receptors can be chemically controlled to enable plant protection against water stress and define the dimeric receptors as key targets for chemical modulation of vegetative ABA responses. PMID:23818638

  9. Activation of dimeric ABA receptors elicits guard cell closure, ABA-regulated gene expression, and drought tolerance.

    PubMed

    Okamoto, Masanori; Peterson, Francis C; Defries, Andrew; Park, Sang-Youl; Endo, Akira; Nambara, Eiji; Volkman, Brian F; Cutler, Sean R

    2013-07-16

    Abscisic acid (ABA) is an essential molecule in plant abiotic stress responses. It binds to soluble pyrabactin resistance1/PYR1-like/regulatory component of ABA receptor receptors and stabilizes them in a conformation that inhibits clade A type II C protein phosphatases; this leads to downstream SnRK2 kinase activation and numerous cellular outputs. We previously described the synthetic naphthalene sulfonamide ABA agonist pyrabactin, which activates seed ABA responses but fails to trigger substantial responses in vegetative tissues in Arabidopsis thaliana. Here we describe quinabactin, a sulfonamide ABA agonist that preferentially activates dimeric ABA receptors and possesses ABA-like potency in vivo. In Arabidopsis, the transcriptional responses induced by quinabactin are highly correlated with those induced by ABA treatments. Quinabactin treatments elicit guard cell closure, suppress water loss, and promote drought tolerance in adult Arabidopsis and soybean plants. The effects of quinabactin are sufficiently similar to those of ABA that it is able to rescue multiple phenotypes observed in the ABA-deficient mutant aba2. Genetic analyses show that quinabactin's effects in vegetative tissues are primarily mediated by dimeric ABA receptors. A PYL2-quinabactin-HAB1 X-ray crystal structure solved at 1.98-Å resolution shows that quinabactin forms a hydrogen bond with the receptor/PP2C "lock" hydrogen bond network, a structural feature absent in pyrabactin-receptor/PP2C complexes. Our results demonstrate that ABA receptors can be chemically controlled to enable plant protection against water stress and define the dimeric receptors as key targets for chemical modulation of vegetative ABA responses.

  10. Characterization of potential ABA receptors in Vitis vinifera.

    PubMed

    Boneh, Uri; Biton, Iris; Zheng, Chuanlin; Schwartz, Amnon; Ben-Ari, Giora

    2012-02-01

    Molecular control mechanisms for abiotic stress tolerance are based on the activation and regulation of specific stress-related genes. The phytohormone abscisic acid (ABA) is a key endogenous messenger in a plant's response to such stresses. A novel ABA binding mechanism which plays a key role in plant cell signaling cascades has recently been uncovered. In the absence of ABA, a type 2C protein phosphatase (PP2C) interacts and inhibits the kinase SnRK2. Binding of ABA to the PYR/PYLs receptors enables interaction between the ABA receptor and the PP2C protein, and abrogates the SnRK2 inactivation. The active SnRK2 is then free to activate the ABA-responsive element Binding Factors which target ABA-dependent gene expression. We used the grape as a model to study the ABA perception mechanism in fruit trees. The grape ABA signaling cascade consists of at least seven ABA receptors and six PP2Cs. We used a yeast two-hybrid system to examine physical interaction in vitro between the grape ABA receptors and their interacting partners, and found that twenty-two receptor-PP2C interactions can occur. Moreover, quantifying these affinities by the use of the LacZ reporter enables us to show that VvPP2C4 and VvPP2C9 are the major binding partners of the ABA receptor. We also tested in vivo the root and leaf gene expression of the various ABA receptors and PP2Cs in the presence of exogenic ABA and under different abiotic stresses such as high salt concentration, cold and drought, and found that many of these genes are regulated by such abiotic environmental factors. Our results indicate organ specificity in the ABA receptor genes and stress specificity in the VvPP2Cs. We suggest that VvPP2C4 is the major PP2C involved in ABA perception in leaves and roots, and VvRCAR6 and VvRCAR5 respectively, are the major receptors involved in ABA perception in these organs. Identification, characterization and manipulation of the central players in the ABA signaling cascades in fruit trees is

  11. Decreased training volume and increased carbohydrate intake increases oxidized LDL levels.

    PubMed

    Välimäki, I A; Vuorimaa, T; Ahotupa, M; Kekkonen, R; Korpela, R; Vasankari, T

    2012-04-01

    We studied effects of probiotics and training volume on oxidized LDL lipids (ox-LDL), serum antioxidant potential (s-TRAP) and serum antioxidants (s-α-tocopherol, s-γ-tocopherol, s-retinol, s-β-carotene and s-ubiquinone-10) in marathon runners during 3-months training period, 6-days preparation period and marathon run. Runners (n=127) were recruited for a randomized, double-blind intervention during which they received either Lactobacillus rhamnosus GG (LGG, probiotic group) or placebo drink (placebo group) during whole study. During the preparation period, subjects decreased training and increased carbohydrate intake. Blood samples were taken at baseline, before 6-days preparation, before and immediately after the marathon. Probiotics did not have any effect on ox-LDL, s-TRAP or serum antioxidants levels during the study. Interestingly, ox-LDL increased by 28% and 33% during the preparation period and decreased by 16% and 19% during the marathon run in the placebo and probiotic groups, respectively (in all, P<0.001). No changes were seen in s-TRAP before marathon, but during run s-TRAP raised by 16% in both groups (both, P<0.001). The increase of ox-LDL level during the preparative period after several months' training suggests that aerobic training may reduce the concentration of ox-LDL and that decrease of training together with increased energy intake, mainly carbohydrate, before marathon is capable of increasing the level of ox-LDL.

  12. Hydrocellular foam dressing increases the leptin level in wound fluid.

    PubMed

    Yoshino, Sawako; Nakagami, Gojiro; Ohira, Tomomi; Kawasaki, Rui; Shimura, Mari; Iwatsuki, Ken; Sanada, Hiromi; Kobayashi-Hattori, Kazuo; Oishi, Yuichi; Yamane, Takumi

    2015-09-01

    Hydrocellular foam dressing (HCF) absorbs excessive wound fluid, which contains various cytokines and growth factors, and ensures a moist environment to promote wound healing. However, the molecular mechanisms underlying the wound fluid component changes induced by HCF are poorly understood. In the present study, we examined the effect of HCF on wound healing and the associated regulatory mechanisms in relation to variations in cytokine levels in the wound fluid. We created full-thickness wounds on the dorsolateral skin of rats and collected the resulting wound fluid samples. HCF was immersed in a plate containing the wound fluids. HCF was then removed and the excess wound fluid remaining in the plate was examined by cytokine array and enzyme-linked immunosorbent assay. We also used a rat model and human dermal fibroblast cultures to examine the effect of wound fluid component changes during the wound healing process. Upon treatment with HCF, leptin levels were upregulated in the wound fluid. Fibroblast proliferation was enhanced and the effect was suppressed in the presence of leptin antagonist. In our in vivo model, HCF increased wound contraction compared with film dressings and this positive effect of HCF was suppressed by addition of leptin antagonist. Our results suggest that dermal fibroblast proliferation is upregulated by HCF due to increased leptin level at the wound surface, and these effects promote wound healing. We believe that the present study contributes to furthering the understanding of the mechanisms underlying the effects of HCF-induced wound healing.

  13. Increased endogenous DNA oxidation correlates to increased iron levels in melanocytes relative to keratinocytes.

    PubMed

    Pelle, Edward; Huang, Xi; Zhang, Qi; Pernodet, Nadine; Yarosh, Daniel B; Frenkel, Krystyna

    2014-01-01

    The endogenous oxidative state of normal human epidermal melanocytes was investigated and compared to normal human epidermal keratinocytes (NHEKs) in order to gain new insight into melanocyte biology. Previously, we showed that NHEKs contain higher levels of hydrogen peroxide (H2O2) than melanocytes and that it can migrate from NHEKs to melanocytes by passive permeation. Nevertheless, despite lower concentrations of H2O2, we now report higher levels of oxidative DNA in melanocytes as indicated by increased levels of 8-oxo-2'-deoxyguanosine (8-oxo-dG): 4.49 (±0.55 SEM) 8-oxo-dG/10(6) dG compared to 1.49 (±0.11 SEM) 8-oxo-dG/10(6) dG for NHEKs. An antioxidant biomarker, glutathione (GSH), was also lower in melanocytes (3.14 nmoles (±0.15 SEM)/cell) in comparison to NHEKs (5.98 nmoles (±0.33 SEM)/cell). Intriguingly, cellular bioavailable iron as measured in ferritin was found to be nearly fourfold higher in melanocytes than in NHEKs. Further, ferritin levels in melanocytes were also higher than in hepatocarcinoma cells, an iron-rich cell, and it indicates that higher relative iron levels may be characteristic of melanocytes. To account for the increased oxidative DNA and lower GSH and H2O2 levels that we observe, we propose that iron may contribute to higher levels of oxidation by reacting with H2O2 through a Fenton reaction leading to the generation of DNA-reactive hydroxyl radicals. In conclusion, our data support the concept of elevated oxidation and high iron levels as normal parameters of melanocytic activity. We present new evidence that may contribute to our understanding of the melanogenic process and lead to the development of new skin care products.

  14. Groundwater depletion's contribution to sea level rise increasing

    NASA Astrophysics Data System (ADS)

    Schultz, Colin

    2011-11-01

    Since the turn of the twentieth century, industrial-scale redistribution of water from landlocked aquifers to the ocean has driven up the global average sea level by more than 12 centimeters. Between 1900 and 2008, roughly 4500 cubic kilometers of water was drawn from the ground, largely to feed an agricultural system increasingly reliant on irrigation. Of that 4500-cubic-kilometer total (nearly the volume of Lake Michigan), 1100 cubic kilometers were pumped out between 2000 and 2008 alone. This early-21st-century groundwater depletion was responsible for raising global sea level at a rate of 0.4 millimeter per year, an eighth of the observed total. These updated values, falling near the middle of the range of previous estimates, are the product of an investigation by Konikow that drew together a variety of volumetric measurements of groundwater storage.

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

    PubMed

    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.

  16. Increased copeptin levels in metabolic syndrome from a Romanian population

    PubMed Central

    Vintilă, M; Gheorghiu, ML; Caragheorgheopol, A; Baculescu, N; Lichiardopol, C; Badiu, C; Coculescu, M; Grigorescu, F; Poiană, C

    2016-01-01

    Rationale: Arginine vasopressin (AVP) is secreted under conditions of water deprivation. Since AVP has a low half-life in the plasma, the C-terminal fragment of AVP-precursor (copeptin) was used to estimate the AVP levels. High copeptin levels increase the risk for the development of diabetes mellitus. Aim: This study was aimed to measure copeptin levels in the metabolic syndrome (MetS) in Romanians using a competitive enzyme immunoassay. Methods and results: Patients prone to present MetS (n = 63) were compared to controls (n = 42). In the MetS group, the syndrome was confirmed in 93.6%. Affected patients displayed 85.7% obesity and insulin resistance (HOMAIR of 4.9 ± 0.4 versus 1.1 ± 0.8 in controls). Low HDL-cholesterol was less represented (47.5%). Copeptin levels were 0.6 ± 0.0 in MetS versus 0.42 ± 0.0 ng/ mL in controls (P < 0.004). Higher copeptin (0.79 to 1.83 ng/ mL) was associated with MetS, P < 0.0018, OR 20, 95%CI [3.03 – 131.7]. In ANOVA, high copeptin was equally explained by MetS or obesity (P < 0.05,α = 3.8). The best correlation was found with high triglyceride levels (P < 0.013,α = 6.3) while the correlation with HOMAIR remained not significant. Discussion: These data indicated a concordant correlation between increased copeptin and MetS or its components. In the light of epidemiological data, indicating that more than 50% of the European population has a lower daily water intake and a fraction of 25% displaying high copeptin, our data further sustained that copeptin may be a good biomarker for MetS and/ or obesity, which should be further investigated with other members of the osmoregulation pathway at both pathogenesis and genetic levels. PMID:27928437

  17. Transgenic cells with increased plastoquinone levels and methods of use

    SciTech Connect

    Sayre, Richard T.; Subramanian, Sowmya; Cahoon, Edgar

    2016-12-27

    Disclosed herein are transgenic cells expressing a heterologous nucleic acid encoding a prephenate dehydrogenase (PDH) protein, a heterologous nucleic acid encoding a homogentisate solanesyl transferase (HST) protein, a heterologous nucleic acid encoding a deoxyxylulose phosphate synthase (DXS) protein, or a combination of two or more thereof. In particular examples, the disclosed transgenic cells have increased plastoquinone levels. Also disclosed are methods of increasing cell growth rates or production of biomass by cultivating transgenic cells expressing a heterologous nucleic acid encoding a PDH protein, a heterologous nucleic acid encoding an HST protein, a heterologous nucleic acid encoding a DXS protein, or a combination of two or more thereof under conditions sufficient to produce cell growth or biomass.

  18. Acute stress induces increases in salivary IL-10 levels.

    PubMed

    Szabo, Yvette Z; Newton, Tamara L; Miller, James J; Lyle, Keith B; Fernandez-Botran, Rafael

    2016-09-01

    The purpose of this study was to investigate the stress-reactivity of the anti-inflammatory cytokine, IL-10, in saliva and to determine how salivary IL-10 levels change in relation to those of IL-1β, a pro-inflammatory cytokine, following stress. Healthy young adults were randomly assigned to retrieve a negative emotional memory (n = 46) or complete a modified version of the Trier Social Stress Test (n = 45). Saliva samples were taken 10 min before (baseline) and 50 min after (post-stressor) onset of a 10-min stressor, and were assayed using a high sensitivity multiplex assay for cytokines. Measurable IL-10 levels (above the minimum detectable concentration) were found in 96% of the baseline samples, and 98% of the post-stressor samples. Flow rate-adjusted salivary IL-10 levels as well as IL-1β/IL-10 ratios showed moderate but statistically significant increases in response to stress. Measurement of salivary IL-10 and pro-/anti-inflammatory cytokine ratios may be useful, noninvasive tools, in stress research.

  19. GsCBRLK, a calcium/calmodulin-binding receptor-like kinase, is a positive regulator of plant tolerance to salt and ABA stress.

    PubMed

    Yang, Liang; Ji, Wei; Zhu, Yanming; Gao, Peng; Li, Yong; Cai, Hua; Bai, Xi; Guo, Dianjing

    2010-05-01

    Calcium/calmodulin-dependent kinases play vital roles in protein phosphorylation in eukaryotes, yet little is known about the phosphorylation process of calcium/calmodulin-dependent protein kinase and its role in stress signal transduction in plants. A novel plant-specific calcium-dependent calmodulin-binding receptor-like kinase (GsCBRLK) has been isolated from Glycine soja. A subcellular localization study using GFP fusion protein indicated that GsCBRLK is localized in the plasma membrane. Binding assays demonstrated that calmodulin binds to GsCBRLK with an affinity of 25.9 nM in a calcium-dependent manner and the binding motif lies between amino acids 147 to169 within subdomain II of the kinase domain. GsCBRLK undergoes autophosphorylation and Myelin Basis Protein phosphorylation in the presence of calcium. It was also found that calcium/calmodulin positively regulates GsCBRLK kinase activity through direct interaction between the calmodulin-binding domain and calmodulin. So, it is likely that GsCBRLK responds to an environmental stimulus in two ways: by increasing the protein expression level and by regulating its kinase activity through the calcium/calmodulin complex. Furthermore, cold, salinity, drought, and ABA stress induce GsCBRLK gene transcripts. Over-expression of GsCBRLK in transgenic Arabidopsis resulted in enhanced plant tolerance to high salinity and ABA and increased the expression pattern of a number of stress gene markers in response to ABA and high salt. These results identify GsCBRLK as a molecular link between the stress- and ABA-induced calcium/calmodulin signal and gene expression in plant cells.

  20. A Role for Arabidopsis miR399f in Salt, Drought, and ABA Signaling

    PubMed Central

    Baek, Dongwon; Chun, Hyun Jin; Kang, Songhwa; Shin, Gilok; Park, Su Jung; Hong, Hyewon; Kim, Chanmin; Kim, Doh Hoon; Lee, Sang Yeol; Kim, Min Chul; Yun, Dae-Jin

    2016-01-01

    MiR399f plays a crucial role in maintaining phosphate homeostasis in Arabidopsis thaliana. Under phosphate starvation conditions, AtMYB2, which plays a role in plant salt and drought stress responses, directly regulates the expression of miR399f. In this study, we found that miR399f also participates in plant responses to abscisic acid (ABA), and to abiotic stresses including salt and drought. Salt and ABA treatment induced the expression of miR399f, as confirmed by histochemical analysis of promoter-GUS fusions. Transgenic Arabidopsis plants overexpressing miR399f (miR399f-OE) exhibited enhanced tolerance to salt stress and exogenous ABA, but hypersensitivity to drought. Our in silico analysis identified ABF3 and CSP41b as putative target genes of miR399f, and expression analysis revealed that mRNA levels of ABF3 and CSP41b decreased remarkably in miR399f-OE plants under salt stress and in response to treatment with ABA. Moreover, we showed that activation of stress-responsive gene expression in response to salt stress and ABA treatment was impaired in miR399f-OE plants. Thus, these results suggested that in addition to phosphate starvation signaling, miR399f might also modulates plant responses to salt, ABA, and drought, by regulating the expression of newly discovered target genes such as ABF3 and CSP41b. PMID:26674968

  1. Abscisic acid (ABA) inhibits light-induced stomatal opening through calcium- and nitric oxide-mediated signaling pathways.

    PubMed

    Garcia-Mata, Carlos; Lamattina, Lorenzo

    2007-01-01

    Nitric oxide (NO) is an important signaling component of ABA-induced stomatal closure. However, only fragmentary data are available about NO effect on the inhibition of stomatal opening. Here, we present results supporting that, in Vicia faba guard cells, there is a critical Ca2+-dependent NO increase required for the ABA-mediated inhibition of stomatal opening. Light-induced stomatal opening was inhibited by exogenous NO in V. faba epidermal strips. Furthermore, ABA-mediated inhibition of stomatal opening was blocked by the specific NO scavenger cPTIO, supporting the involvement of endogenous NO in this process. Since the raise in Ca2+ concentration is a pre-requisite in ABA-mediated inhibition of stomatal opening, it was interesting to establish how does Ca2+, NO and ABA interact in the inhibition of light-induced stomatal opening. The permeable Ca2+ specific buffer BAPTA-AM blocked both ABA- and Ca2+- but not NO-mediated inhibition of stomatal opening. The NO synthase (NOS) specific inhibitor L-NAME prevented Ca2+-mediated inhibition of stomatal opening, indicating that a NOS-like activity was required for Ca2+ signaling. Furthermore, experiments using the NO specific fluorescent probe DAF-2DA indicated that Ca2+ induces an increase of endogenous NO. These results indicate that, in addition to the roles in ABA-triggered stomatal closure, both NO and Ca2+ are active components of signaling events acting in ABA inhibition of light-induced stomatal opening. Results also support that Ca2+ induces the NO production through the activation of a NOS-like activity.

  2. Phytoplankton succession during acidification with and without increasing aluminum levels.

    PubMed

    Havens, K E; Heath, R T

    1990-01-01

    An in situ mesocosm experiment was performed to investigate the role of aluminum in controlling phytoplankton community succession during lake acidification. Large (2000 liter) mesocosms were suspended in mesotrophic East Twin Lake, Ohio, USA. Duplicates were either untreated controls (pH 8.8), acidified to pH 4.5 over 23 days, or acidified and spiked with 200 microg/liter Al in incremental additions. Filamentous blue greens, diatoms and other chrysophytes became extinct in both acid treatments, but declined most rapidly where Al levels were also increased. The large desmid Closterium and the filamentous chlorophyte Mougoetia became dominant in the Acid treatment. In the Acid + Al treatment, these algae also became dominant, but the species with greatest biomass was the dinoflagellate Peridinium inconspicuum. Acidification (with or without added Al) also resulted in a significant shift in the algal size spectrum to larger (> 20 microm) cells.

  3. Increased levels of sister chromatid exchanges in military aircraft pilots.

    PubMed

    Silva, M J; Carothers, A; Castelo Branco, N; Dias, A; Boavida, M G

    1999-04-26

    Sister chromatid exchanges (SCEs) were scored in lymphocytes of nine high-performance pilots of alphajet aircrafts and of ten control individuals from the same air base. Statistical analysis of the mean SCE count per cell in the total number of cells analyzed as well as in those having 12 or more SCEs (high-frequency cells, HFCs) revealed a significant difference between pilots and controls, after adjusting for the effect of smoking. Analysis of the cell cycle kinetic data (replication and mitotic indices) revealed no significant differences either between pilots and controls or between smokers and nonsmokers. Previously, we reported an increase in the SCE levels in workers of the aeronautical industry exposed to noise and whole-body vibration. The present results corroborate those findings and indicate that noise and whole-body vibration may cause genotoxic effects in man.

  4. Artificially Increased Yolk Hormone Levels and Neophobia in Domestic Chicks

    PubMed Central

    Bertin, Aline; Arnould, Cécile; Moussu, Chantal; Meurisse, Maryse; Constantin, Paul; Leterrier, Christine; Calandreau, Ludovic

    2015-01-01

    In birds there is compelling evidence that the development and expression of behavior is affected by maternal factors, particularly via variation in yolk hormone concentrations of maternal origin. In the present study we tested whether variation in yolk hormone levels lead to variation in the expression of neophobia in young domestic chicks. Understanding how the prenatal environment could predispose chicks to express fear-related behaviors is essential in order to propose preventive actions and improve animal welfare. We simulated the consequences of a maternal stress by experimentally enhancing yolk progesterone, testosterone and estradiol concentrations in hen eggs prior to incubation. The chicks from these hormone-treated eggs (H) and from sham embryos (C) that received the vehicle-only were exposed to novel food, novel object and novel environment tests. H chicks approached a novel object significantly faster and were significantly more active in a novel environment than controls, suggesting less fearfulness. Conversely, no effect of the treatment was found in food neophobia tests. Our study highlights a developmental influence of yolk hormones on a specific aspect of neophobia. The results suggest that increased yolk hormone levels modulate specifically the probability of exploring novel environments or novel objects in the environment. PMID:26633522

  5. Towards engineering increased pantothenate (vitamin B(5)) levels in plants.

    PubMed

    Chakauya, Ereck; Coxon, Katy M; Wei, Ma; Macdonald, Mary V; Barsby, Tina; Abell, Chris; Smith, Alison G

    2008-11-01

    Pantothenate (vitamin B(5)) is the precursor of the 4'-phosphopantetheine moiety of coenzyme A and acyl-carrier protein. It is made by plants and microorganisms de novo, but is a dietary requirement for animals. The pantothenate biosynthetic pathway is well-established in bacteria, comprising four enzymic reactions catalysed by ketopantoate hydroxymethyltransferase (KPHMT), L: -aspartate-alpha-decarboxylase (ADC), pantothenate synthetase (PS) and ketopantoate reductase (KPR) encoded by panB, panD, panC and panE genes, respectively. In higher plants, the genes encoding the first (KPHMT) and last (PS) enzymes have been identified and characterised in several plant species. Commercially, pantothenate is chemically synthesised and used in vitamin supplements, feed additives and cosmetics. Biotransformation is an attractive alternative production system that would circumvent the expensive procedures of separating racemic intermediates. We explored the possibility of manipulating pantothenate biosynthesis in plants. Transgenic oilseed rape (Brassica napus) lines were generated in which the E. coli KPHMT and PS genes were expressed under a strong constitutive CaMV35SS promoter. No significant change of pantothenate levels in PS transgenic lines was observed. In contrast plants expressing KPHMT had elevated pantothenate levels in leaves, flowers siliques and seed in the range of 1.5-2.5 fold increase compared to the wild type plant. Seeds contained the highest vitamin content, indicating that they might be the ideal target for production purposes.

  6. A G-protein β subunit, AGB1, negatively regulates the ABA response and drought tolerance by down-regulating AtMPK6-related pathway in Arabidopsis.

    PubMed

    Xu, Dong-bei; Chen, Ming; Ma, Ya-nan; Xu, Zhao-shi; Li, Lian-cheng; Chen, Yao-feng; Ma, You-zhi

    2015-01-01

    Heterotrimeric G-proteins are versatile regulators involved in diverse cellular processes in eukaryotes. In plants, the function of G-proteins is primarily associated with ABA signaling. However, the downstream effectors and the molecular mechanisms in the ABA pathway remain largely unknown. In this study, an AGB1 mutant (agb1-2) was found to show enhanced drought tolerance, indicating that AGB1 might negatively regulate drought tolerance in Arabidopsis. Data showed that AGB1 interacted with protein kinase AtMPK6 that was previously shown to phosphorylate AtVIP1, a transcription factor responding to ABA signaling. Our study found that transcript levels of three ABA responsive genes, AtMPK6, AtVIP1 and AtMYB44 (downstream gene of AtVIP1), were significantly up-regulated in agb1-2 lines after ABA or drought treatments. Other ABA-responsive and drought-inducible genes, such as RD29A (downstream gene of AtMYB44), were also up-regulated in agb1-2 lines. Furthermore, overexpression of AtVIP1 resulted in hypersensitivity to ABA at seed germination and seedling stages, and significantly enhanced drought tolerance in transgenic plants. These results suggest that AGB1 was involved in the ABA signaling pathway and drought tolerance in Arabidopsis through down-regulating the AtMPK6, AtVIP1 and AtMYB44 cascade.

  7. An ABA-responsive DRE-binding protein gene from Setaria italica, SiARDP, the target gene of SiAREB, plays a critical role under drought stress

    PubMed Central

    Li, Cong; Yue, Jing; Wu, Xiaowei; Xu, Cong; Yu, Jingjuan

    2014-01-01

    The DREB (dehydration-responsive element binding)-type transcription factors regulate the expression of stress-inducible genes by binding the DRE/CRT cis-elements in promoter regions. The upstream transcription factors that regulate the transcription of DREB transcription factors have not been clearly defined, although the function of DREB transcription factors in abiotic stress is known. In this study, an abscisic acid (ABA)-responsive DREB-binding protein gene (SiARDP) was cloned from foxtail millet (Setaria italica). The transcript level of SiARDP increased not only after drought, high salt, and low temperature stresses, but also after an ABA treatment in foxtail millet seedlings. Two ABA-responsive elements (ABRE1: ACGTGTC; ABRE2: ACGTGGC) exist in the promoter of SiARDP. Further analyses showed that two ABA-responsive element binding (AREB)-type transcription factors, SiAREB1 and SiAREB2, could physically bind to the ABRE core element in vitro and in vivo. The constitutive expression of SiARDP in Arabidopsis thaliana enhanced drought and salt tolerance during seed germination and seedling development, and overexpression of SiARDP in foxtail millet improved drought tolerance. The expression levels of target genes of SiARDP were upregulated in transgenic Arabidopsis and foxtail millet. These results reveal that SiARDP, one of the target genes of SiAREB, is involved in ABA-dependent signal pathways and plays a critical role in the abiotic stress response in plants. PMID:25071221

  8. Identification of OsbZIP72 as a positive regulator of ABA response and drought tolerance in rice.

    PubMed

    Lu, Guojun; Gao, Chenxi; Zheng, Xingnan; Han, Bin

    2009-02-01

    Abscisic Acid (ABA) is an important phytohormone involved in abiotic stress resistance in plants. A group of bZIP transcription factors play important roles in the ABA signaling pathway in Arabidopsis. However, little is known about the function of their orthologs in rice, where they may hold a great potential for developing drought resistant food crops. In this study, our phylogenetic analysis showed that this group of bZIPs was evolutionarily conserved between Arabidopsis and rice, which implies that they may share similar functions. We demonstrated with quantitative RT-PCR that the expressions of most of these OsbZIPs were significantly induced by ABA, ACC, and abiotic stresses. OsbZIP72, a member of this group, was proved to be an ABRE binding factor in rice using the yeast hybrid systems. We showed that it could bind to ABRE and transactivate the downstream reporter genes in yeast, and the transactivity was depending on its N-terminal region. Transgenic rice overexpressing OsbZIP72 showed a hypersensitivity to ABA, elevated levels of expression of ABA response gene such as LEAs, and an enhanced ability of drought tolerance. These results suggest that OsbZIP72 plays a positive role in drought resistance through ABA signaling, and is potential useful for engineering drought tolerant rice.

  9. Effect of Increased Water Vapor Levels on TBC Lifetime

    SciTech Connect

    Pint, Bruce A; Garner, George Walter; Lowe, Tracie M; Haynes, James A; Zhang, Ying

    2011-01-01

    To investigate the effect of increased water vapor levels on thermal barrier coating (TBC) lifetime, furnace cycle tests were performed at 1150 C in air with 10 vol.% water vapor (similar to natural gas combustion) and 90 vol.%. Either Pt diffusion or Pt-modified aluminide bond coatings were applied to specimens from the same batch of a commercial second-generation single-crystal superalloy and commercial vapor-deposited yttria-stabilized zirconia (YSZ) top coats were applied. Three coatings of each type were furnace cycled to failure to compare the average lifetimes obtained in dry O{sub 2}, using the same superalloy batch and coating types. Average lifetimes with Pt diffusion coatings were unaffected by the addition of water vapor. In contrast, the average lifetime of Pt-modified aluminide coatings was reduced by more than 50% with 10% water vapor but only slightly reduced by 90% water vapor. Based on roughness measurements from similar specimens without a YSZ coating, the addition of 10% water vapor increased the rate of coating roughening more than 90% water vapor. Qualitatively, the amount of {beta}-phase depletion in the coatings exposed in 10% water vapor did not appear to be accelerated.

  10. Enforced physical inactivity increases endothelial microparticle levels in healthy volunteers.

    PubMed

    Navasiolava, Nastassia M; Dignat-George, Françoise; Sabatier, Florence; Larina, Irina M; Demiot, Claire; Fortrat, Jacques-Olivier; Gauquelin-Koch, Guillemette; Kozlovskaya, Inesa B; Custaud, Marc-Antoine

    2010-08-01

    A sedentary lifestyle has adverse effects on the cardiovascular system, including impaired endothelial functions. Subjecting healthy men to 7 days of dry immersion (DI) presented a unique opportunity to analyze the specific effects of enhanced inactivity on the endothelium. We investigated endothelial properties before, during, and after 7 days of DI involving eight subjects. Microcirculatory functions were assessed with laser Doppler in the skin of the calf. We studied basal blood flow and endothelium-dependent and -independent vasodilation. We also measured plasma levels of microparticles, a sign of cellular dysfunction, and soluble endothelial factors, reflecting the endothelial state. Basal flow and endothelium-dependent vasodilation were reduced by DI (22 + or - 4 vs. 15 + or - 2 arbitrary units and 29 + or - 6% vs. 12 + or - 6%, respectively, P < 0.05), and this was accompanied by an increase in circulating endothelial microparticles (EMPs), which was significant on day 3 (42 + or - 8 vs. 65 + or - 10 EMPs/microl, P < 0.05), whereas microparticles from other cell origins remained unchanged. Plasma soluble VEGF decreased significantly during DI, whereas VEGF receptor 1 and soluble CD62E were unchanged, indicating that the increase in EMPs was associated with a change in antiapoptotic tone rather than endothelial activation. Our study showed that extreme physical inactivity in humans induced by 7 days of DI causes microvascular impairment with a disturbance of endothelial functions, associated with a selective increase in EMPs. Microcirculatory endothelial dysfunction might contribute to cardiovascular deconditioning as well as to hypodynamia-associated pathologies. In conclusion, the endothelium should be the focus of special care in situations of acute limitation of physical activity.

  11. Increased abscisic acid levels in transgenic maize overexpressing AtLOS5 mediated root ion fluxes and leaf water status under salt stress.

    PubMed

    Zhang, Juan; Yu, Haiyue; Zhang, Yushi; Wang, Yubing; Li, Maoying; Zhang, Jiachang; Duan, Liusheng; Zhang, Mingcai; Li, Zhaohu

    2016-03-01

    Abscisic acid (ABA) is a vital cellular signal in plants, and effective ABA signalling is pivotal for stress tolerance. AtLOS5 encoding molybdenum cofactor sulphurase is a key regulator of ABA biosynthesis. Here, transgenic AtLOS5 plants were generated to explore the role of AtLOS5 in salt tolerance in maize. AtLOS5 overexpression significantly up-regulated the expression of ZmVp14-2, ZmAO, and ZmMOCO, and increased aldehyde oxidase activities, which enhanced ABA accumulation in transgenic plants under salt stress. Concurrently, AtLOS5 overexpression induced the expression of ZmNHX1, ZmCBL4, and ZmCIPK16, and enhanced the root net Na(+) efflux and H(+) influx, but decreased net K(+) efflux, which maintained a high cytosolic K(+)/Na(+) ratio in transgenic plants under salt stress. However, amiloride or sodium orthovanadate could significantly elevate K(+) effluxes and decrease Na(+) efflux and H(+) influx in salt-treated transgenic roots, but the K(+) effluxes were inhibited by TEA, suggesting that ion fluxes regulated by AtLOS5 overexpression were possibly due to activation of Na(+)/H(+) antiport and K(+) channels across the plasma membrane. Moreover, AtLOS5 overexpression could up-regulate the transcripts of ZmPIP1:1, ZmPIP1:5, and ZmPIP2:4, and enhance root hydraulic conductivity. Thus transgenic plants had higher leaf water potential and turgor, which was correlated with greater biomass accumulation under salt stress. Thus AtLOS5 overexpression induced the expression of ABA biosynthetic genes to promote ABA accumulation, which activated ion transporter and PIP aquaporin gene expression to regulate root ion fluxes and water uptake, thus maintaining high cytosolic K(+) and Na(+) homeostasis and better water status in maize exposed to salt stress.

  12. Increased abscisic acid levels in transgenic maize overexpressing AtLOS5 mediated root ion fluxes and leaf water status under salt stress

    PubMed Central

    Zhang, Juan; Yu, Haiyue; Zhang, Yushi; Wang, Yubing; Li, Maoying; Zhang, Jiachang; Duan, Liusheng; Zhang, Mingcai; Li, Zhaohu

    2016-01-01

    Abscisic acid (ABA) is a vital cellular signal in plants, and effective ABA signalling is pivotal for stress tolerance. AtLOS5 encoding molybdenum cofactor sulphurase is a key regulator of ABA biosynthesis. Here, transgenic AtLOS5 plants were generated to explore the role of AtLOS5 in salt tolerance in maize. AtLOS5 overexpression significantly up-regulated the expression of ZmVp14-2, ZmAO, and ZmMOCO, and increased aldehyde oxidase activities, which enhanced ABA accumulation in transgenic plants under salt stress. Concurrently, AtLOS5 overexpression induced the expression of ZmNHX1, ZmCBL4, and ZmCIPK16, and enhanced the root net Na+ efflux and H+ influx, but decreased net K+ efflux, which maintained a high cytosolic K+/Na+ ratio in transgenic plants under salt stress. However, amiloride or sodium orthovanadate could significantly elevate K+ effluxes and decrease Na+ efflux and H+ influx in salt-treated transgenic roots, but the K+ effluxes were inhibited by TEA, suggesting that ion fluxes regulated by AtLOS5 overexpression were possibly due to activation of Na+/H+ antiport and K+ channels across the plasma membrane. Moreover, AtLOS5 overexpression could up-regulate the transcripts of ZmPIP1:1, ZmPIP1:5, and ZmPIP2:4, and enhance root hydraulic conductivity. Thus transgenic plants had higher leaf water potential and turgor, which was correlated with greater biomass accumulation under salt stress. Thus AtLOS5 overexpression induced the expression of ABA biosynthetic genes to promote ABA accumulation, which activated ion transporter and PIP aquaporin gene expression to regulate root ion fluxes and water uptake, thus maintaining high cytosolic K+ and Na+ homeostasis and better water status in maize exposed to salt stress. PMID:26743432

  13. Medial Prefrontal Cortex Involvement in the Expression of Extinction and ABA Renewal of Instrumental Behavior for a Food Reinforcer

    PubMed Central

    Eddy, Meghan C.; Todd, Travis P.; Bouton, Mark E.; Green, John T.

    2015-01-01

    Instrumental renewal, the return of extinguished instrumental responding after removal from the extinction context, is an important model of behavioral relapse that is poorly understood at the neural level. In two experiments, we examined the role of the dorsomedial prefrontal cortex (dmPFC) and the ventromedial prefrontal cortex (vmPFC) in extinction and ABA renewal of instrumental responding for a sucrose reinforcer. Previous work, exclusively using drug reinforcers, has suggested that the roles of the dmPFC and vmPFC in expression of extinction and ABA renewal may depend at least in part on the type of drug reinforcer used. The current experiments used a food reinforcer because the behavioral mechanisms underlying the extinction and renewal of instrumental responding are especially well worked out in this paradigm. After instrumental conditioning in context A and extinction in context B, we inactivated dmPFC, vmPFC, or a more ventral medial prefrontal cortex region by infusing baclofen/muscimol (B/M) just prior to testing in both contexts. In rats with inactivated dmPFC, ABA renewal was still present (i.e., responding increased when returned to context A); however responding was lower (less renewal) than controls. Inactivation of vmPFC increased responding in context B (the extinction context) and decreased responding in context A, indicating no renewal in these animals. There was no effect of B/M infusion on rats with cannula placements ventral to the vmPFC. Fluorophore-conjugated muscimol was infused in a subset of rats following test to visualize infusion spread. Imaging suggested that the infusion spread was minimal and mainly constrained to the targeted area. Together, these experiments suggest that there is a region of medial prefrontal cortex encompassing both dmPFC and vmPFC that is important for ABA renewal of extinguished instrumental responding for a food reinforcer. In addition, vmPFC, but not dmPFC, is important for expression of extinction of

  14. Medial prefrontal cortex involvement in the expression of extinction and ABA renewal of instrumental behavior for a food reinforcer.

    PubMed

    Eddy, Meghan C; Todd, Travis P; Bouton, Mark E; Green, John T

    2016-02-01

    Instrumental renewal, the return of extinguished instrumental responding after removal from the extinction context, is an important model of behavioral relapse that is poorly understood at the neural level. In two experiments, we examined the role of the dorsomedial prefrontal cortex (dmPFC) and the ventromedial prefrontal cortex (vmPFC) in extinction and ABA renewal of instrumental responding for a sucrose reinforcer. Previous work, exclusively using drug reinforcers, has suggested that the roles of the dmPFC and vmPFC in expression of extinction and ABA renewal may depend at least in part on the type of drug reinforcer used. The current experiments used a food reinforcer because the behavioral mechanisms underlying the extinction and renewal of instrumental responding are especially well worked out in this paradigm. After instrumental conditioning in context A and extinction in context B, we inactivated dmPFC, vmPFC, or a more ventral medial prefrontal cortex region by infusing baclofen/muscimol (B/M) just prior to testing in both contexts. In rats with inactivated dmPFC, ABA renewal was still present (i.e., responding increased when returned to context A); however responding was lower (less renewal) than controls. Inactivation of vmPFC increased responding in context B (the extinction context) and decreased responding in context A, indicating no renewal in these animals. There was no effect of B/M infusion on rats with cannula placements ventral to the vmPFC. Fluorophore-conjugated muscimol was infused in a subset of rats following test to visualize infusion spread. Imaging suggested that the infusion spread was minimal and mainly constrained to the targeted area. Together, these experiments suggest that there is a region of medial prefrontal cortex encompassing both dmPFC and vmPFC that is important for ABA renewal of extinguished instrumental responding for a food reinforcer. In addition, vmPFC, but not dmPFC, is important for expression of extinction of

  15. Water stress, CO2 and photoperiod influence hormone levels in wheat

    NASA Technical Reports Server (NTRS)

    Nan, Rubin; Carman, John G.; Salisbury, Frank B.; Campbell, W. F. (Principal Investigator)

    2002-01-01

    'Super Dwarf' wheat (Triticum aestivum L.) plants have been grown from seed to maturity in the Mir space station where they were periodically exposed, because of microgravity and other constraints, to water deficit, waterlogging, high CO2 levels, and low light intensities. The plants produced many tillers, but none of them produced viable seed. Studies have been initiated to determine why the plants responded in these ways. In the present study, effects of the listed stresses on abscisic acid (ABA), indole-3-acetic acid (IAA) and isopentenyl adenosine ([9R]iP) levels in roots and leaves of plants grown under otherwise near optimal conditions on earth were measured. Hormones were extracted, purified by HPLC, and quantified by noncompetitive indirect ELISA. In response to water deficit, ABA levels increased in roots and leaves, IAA levels decreased in roots and leaves, and [9R]iP levels increased in leaves but decreased in roots. In response to waterlogging, ABA, IAA and [9R]iP levels briefly increased in roots and leaves and then decreased. When portions of the root system were exposed to waterlogging and/or water deficit, ABA levels in leaves increased while [9R]iP and IAA levels decreased. These responses were correlated with the percentage of the root system stressed. At a low photosynthetic photon flux (100 micromoles m-2 s-1), plants grown in continuous light had higher leaf ABA levels than plants grown using an 18 or 21 h photoperiod.

  16. Water stress, CO2 and photoperiod influence hormone levels in wheat.

    PubMed

    Nan, Rubin; Carman, John G; Salisbury, Frank B

    2002-03-01

    'Super Dwarf' wheat (Triticum aestivum L.) plants have been grown from seed to maturity in the Mir space station where they were periodically exposed, because of microgravity and other constraints, to water deficit, waterlogging, high CO2 levels, and low light intensities. The plants produced many tillers, but none of them produced viable seed. Studies have been initiated to determine why the plants responded in these ways. In the present study, effects of the listed stresses on abscisic acid (ABA), indole-3-acetic acid (IAA) and isopentenyl adenosine ([9R]iP) levels in roots and leaves of plants grown under otherwise near optimal conditions on earth were measured. Hormones were extracted, purified by HPLC, and quantified by noncompetitive indirect ELISA. In response to water deficit, ABA levels increased in roots and leaves, IAA levels decreased in roots and leaves, and [9R]iP levels increased in leaves but decreased in roots. In response to waterlogging, ABA, IAA and [9R]iP levels briefly increased in roots and leaves and then decreased. When portions of the root system were exposed to waterlogging and/or water deficit, ABA levels in leaves increased while [9R]iP and IAA levels decreased. These responses were correlated with the percentage of the root system stressed. At a low photosynthetic photon flux (100 micromoles m-2 s-1), plants grown in continuous light had higher leaf ABA levels than plants grown using an 18 or 21 h photoperiod.

  17. Sucrose and ABA regulate starch biosynthesis in maize through a novel transcription factor, ZmEREB156

    PubMed Central

    Huang, Huanhuan; Xie, Sidi; Xiao, Qianlin; Wei, Bin; Zheng, Lanjie; Wang, Yongbin; Cao, Yao; Zhang, Xiangge; Long, Tiandan; Li, Yangping; Hu, Yufeng; Yu, Guowu; Liu, Hanmei; Liu, Yinghong; Huang, Zhi; Zhang, Junjie; Huang, Yubi

    2016-01-01

    Sucrose is not only the carbon source for starch synthesis, but also a signal molecule. Alone or in coordination with ABA, it can regulate the expression of genes involved in starch synthesis. To investigate the molecular mechanisms underlying this effect, maize endosperms were collected from Zea mays L. B73 inbred line 10 d after pollination and treated with sucrose, ABA, or sucrose plus ABA at 28 °C in the dark for 24 h. RNA-sequence analysis of the maize endosperm transcriptome revealed 47 candidate transcription factors among the differentially expressed genes. We therefore speculate that starch synthetic gene expression is regulated by transcription factors induced by the combination of sucrose and ABA. ZmEREB156, a candidate transcription factor, is induced by sucrose plus ABA and is involved in starch biosynthesis. The ZmEREB156-GFP-fused protein was localized in the nuclei of onion epidermal cells, and ZmEREB156 protein possessed strong transcriptional activation activity. Promoter activity of the starch-related genes Zmsh2 and ZmSSIIIa increased after overexpression of ZmEREB156 in maize endosperm. ZmEREB156 could bind to the ZmSSIIIa promoter but not the Zmsh2 promoter in a yeast one-hybrid system. Thus, ZmEREB156 positively modulates starch biosynthetic gene ZmSSIIIa via the synergistic effect of sucrose and ABA. PMID:27282997

  18. Effects of ABA and CaCl₂ on GABA accumulation in fava bean germinating under hypoxia-NaCl stress.

    PubMed

    Yang, Runqiang; Hui, Qianru; Gu, Zhenxin

    2016-01-01

    Effects of exogenous abscisic acid (ABA) and CaCl2 on γ-aminobutyric acid (GABA) accumulation of germinated fava bean under hypoxia-NaCl stress were investigated. Exogenous ABA resulted in the enhancement of glutamate decarboxylase (GAD) and diamine oxidase (DAO) activity as well as GABA content in cotyledon and shoot. CaCl2 increased both enzyme activities in shoot and GABA content in cotyledon and shoot. ABA downregulated GAD expression in cotyledon and radicle, while upregulated that in shoot; it also upregulated DAO expression in each organ. CaCl2 upregulated GAD expression in cotyledon, while downregulated that in radicle. However, it upregulated DAO expression in shoot, downregulated that in radicle. ABA inhibitor fluridon and ethylenediaminetetraacetic acid inhibited GAD and DAO activities significantly so that inhibited GABA accumulation through reducing ABA biosynthesis and chelating Ca(2+), respectively. However, they upregulated GAD and DAO expression in varying degrees. These results indicate that ABA and Ca(2+) participate in GABA biosynthesis in fava bean during germination under hypoxia-NaCl stress.

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

    PubMed Central

    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

  20. Increase in voice level and speaker comfort in lecture rooms.

    PubMed

    Brunskog, Jonas; Gade, Anders Christian; Bellester, Gaspar Payá; Calbo, Lilian Reig

    2009-04-01

    Teachers often suffer from health problems related to their voice. These problems are related to their working environment, including the acoustics of the lecture rooms. However, there is a lack of studies linking the room acoustic parameters to the voice produced by the speaker. In this pilot study, the main goals are to investigate whether objectively measurable parameters of the rooms can be related to an increase in the voice sound power produced by speakers and to the speakers' subjective judgments about the rooms. In six different rooms with different sizes, reverberation times, and other physical attributes, the sound power level produced by six speakers was measured. Objective room acoustic parameters were measured in the same rooms, including reverberation time and room gain, and questionnaires were handed out to people who had experience talking in the rooms. It is found that in different rooms significant changes in the sound power produced by the speaker can be found. It is also found that these changes mainly have to do with the size of the room and to the gain produced by the room. To describe this quality, a new room acoustic quantity called "room gain" is proposed.

  1. Wheat ABA-insensitive mutants result in reduced grain dormancy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper describes the isolation of wheat mutants in the hard red spring Scarlet resulting in reduced sensitivity to the plant hormone abscisic acid (ABA) during seed germination. ABA induces seed dormancy during embryo maturation and inhibits the germination of mature seeds. Wheat sensitivity t...

  2. Root ABA Accumulation Enhances Rice Seedling Drought Tolerance under Ammonium Supply: Interaction with Aquaporins

    PubMed Central

    Ding, Lei; Li, Yingrui; Wang, Ying; Gao, Limin; Wang, Min; Chaumont, François; Shen, Qirong; Guo, Shiwei

    2016-01-01

    In previous studies, we demonstrated that ammonium nutrition enhances the drought tolerance of rice seedlings compared to nitrate nutrition and contributes to a higher root water uptake ability. It remains unclear why rice seedlings maintain a higher water uptake ability when supplied with ammonium under drought stress. Here, we focused on the effects of nitrogen form and drought stress on root abscisic acid (ABA) concentration and aquaporin expression using hydroponics experiments and stimulating drought stress with 10% PEG6000. Drought stress decreased the leaf photosynthetic rate and stomatal conductivity and increased the leaf temperature of plants supplied with either ammonium or nitrate, but especially under nitrate supply. After 4 h of PEG treatment, the root protoplast water permeability and the expression of root PIP and TIP genes decreased in plants supplied with ammonium or nitrate. After 24 h of PEG treatment, the root hydraulic conductivity, the protoplast water permeability, and the expression of some aquaporin genes increased in plants supplied with ammonium compared to those under non-PEG treatment. Root ABA accumulation was induced by 24 h of PEG treatment, especially in plants supplied with ammonium. The addition of exogenous ABA decreased the expression of PIP and TIP genes under non-PEG treatment but increased the expression of some of them under PEG treatment. We concluded that drought stress induced a down-regulation of aquaporin expression, which appeared earlier than did root ABA accumulation. With continued drought stress, aquaporin expression and activity increased due to root ABA accumulation in plants supplied with ammonium. PMID:27559341

  3. Increased cerebrospinal fluid pyruvate levels in Alzheimer's disease.

    PubMed

    Parnetti, L; Gaiti, A; Polidori, M C; Brunetti, M; Palumbo, B; Chionne, F; Cadini, D; Cecchetti, R; Senin, U

    1995-10-27

    Impaired energy metabolism is an early, predominant feature in Alzheimer's disease. In order to find out simple, reliable 'in vivo' markers for the clinical-biological typization of the disorder, we measured cerebrospinal fluid (CSF) glucose, lactate and pyruvate levels in patients suffering from dementia of Alzheimer type (DAT) and in healthy elderly controls. DAT group showed remarkably higher levels of pyruvate (P = 0.01), with no overlap with the values obtained in controls. CSF pyruvate levels were also significantly associated with the severity of dementia. Therefore, CSF pyruvate levels neatly separate DAT patients from controls, having also pathogenetic value.

  4. ABA induces H2O2 production in guard cells, but does not close the stomata on Vicia faba leaves developed at high air humidity.

    PubMed

    Arve, Louise E; Carvalho, Dália R A; Olsen, Jorunn E; Torre, Sissel

    2014-01-01

    Plants developed under constant high (> 85%) relative air humidity (RH) have larger stomata that are unable to close completely. One of the hypotheses for the less responsive stomata is that the plants have reduced sensitivity to abscisic acid (ABA). Both ABA and darkness are signals for stomatal closure and induce the production of the secondary messenger hydrogen peroxide (H2O2). In this study, the ability of Vicia faba plants developed in moderate or high RH to close the stomata in response to darkness, ABA and H2O2 was investigated. Moreover, the ability of the plants to produce H2O2 when treated with ABA or transferred to darkness was also assessed. Our results show that the ABA concentration in moderate RH is not increased during darkness even though the stomata are closing. This indicates that stomatal closure in V. faba during darkness is independent of ABA production. ABA induced both H2O2 production and stomatal closure in stomata formed at moderate RH. H2O2 production, as a result of treatment with ABA, was also observed in stomata formed at high RH, though the closing response was considerably smaller as compared with moderate RH. In either RH, leaf ABA concentration was not affected by darkness. Similarly to ABA treatment, darkness elicited both H2O2 production and stomatal closure following plant cultivation at moderate RH. Contrary to this, neither H2O2 production nor stomatal closure took place when stomata were formed at high RH. These results suggest that the reduced stomatal response in plants developed in continuous high RH is caused by one or more factors downstream of H2O2 in the signaling pathway toward stomatal closure.

  5. Estuaries May Face Increased Parasitism as Sea Levels Rise

    NASA Astrophysics Data System (ADS)

    Wendel, JoAnna

    2014-12-01

    Invertebrates in estuaries could be at a greater risk of parasitism as climate change causes sea levels to rise. A new paper published 8 December in Proceedings of the National Academy of Sciences of the United States of America (doi:10.1073/pnas.1416747111) describes how rapid sea level rise in the Holocene affected the population of parasitic flatworms called trematodes.

  6. Stomatal malfunctioning under low VPD conditions: induced by alterations in stomatal morphology and leaf anatomy or in the ABA signaling?

    PubMed

    Aliniaeifard, Sasan; Malcolm Matamoros, Priscila; van Meeteren, Uulke

    2014-12-01

    Exposing plants to low VPD reduces leaf capacity to maintain adequate water status thereafter. To find the impact of VPD on functioning of stomata, stomatal morphology and leaf anatomy, fava bean plants were grown at low (L, 0.23 kPa) or moderate (M, 1.17 kPa) VPDs and some plants that developed their leaves at moderate VPD were then transferred for 4 days to low VPD (M→L). Part of the M→L-plants were sprayed with ABA (abscisic acid) during exposure to L. L-plants showed bigger stomata, larger pore area, thinner leaves and less spongy cells compared with M-plants. Stomatal morphology (except aperture) and leaf anatomy of the M→L-plants were almost similar to the M-plants, while their transpiration rate and stomatal conductance were identical to that of L-plants. The stomatal response to ABA was lost in L-plants, but also after 1-day exposure of M-plants to low VPD. The level of foliar ABA sharply decreased within 1-day exposure to L, while the level of ABA-GE (ABA-glucose ester) was not affected. Spraying ABA during the exposure to L prevented loss of stomatal closing response thereafter. The effect of low VPD was largely depending on exposure time: the stomatal responsiveness to ABA was lost after 1-day exposure to low VPD, while the responsiveness to desiccation was gradually lost during 4-day exposure to low VPD. Leaf anatomical and stomatal morphological alterations due to low VPD were not the main cause of loss of stomatal closure response to closing stimuli.

  7. MYB96 shapes the circadian gating of ABA signaling in Arabidopsis

    PubMed Central

    Lee, Hong Gil; Mas, Paloma; Seo, Pil Joon

    2016-01-01

    Circadian clocks regulate the rhythms of biological activities with a period of approximately 24-hours and synchronize plant metabolism and physiology with the environmental cycles. The clock also gates responses to environmental stresses to maximize fitness advantages. Here we report that the MYB96 transcription factor is connected with the clock oscillator to shape the circadian gating of abscisic acid (ABA) responses. MYB96 directly binds to the TIMING OF CAB EXPRESSION 1 (TOC1) promoter to positively regulate its expression. The use of myb96 mutant plants shows that this regulation is essential for the gated induction of TOC1 by ABA. In turn, MYB96 induction by ABA is also altered in toc1-3 mutant plants. The increased tolerance to drought of MYB96 over-expressing plants is decreased in the toc1-3 mutant background, suggesting that MYB96 and TOC1 intersect the circadian clock and ABA signaling. The MYB96-TOC1 function might be also regulated by the clock component CIRCADIAN CLOCK-ASSOCIATED 1 (CCA1), which binds to the MYB96 promoter and alters its circadian expression. Thus, a complex circuitry of CCA1-MYB96-TOC1 regulatory interactions provides the mechanistic basis underlying the connection between circadian and stress signaling to optimize plant fitness to ambient stresses. PMID:26725725

  8. Overexpression of an ABA biosynthesis gene using a stress-inducible promoter enhances drought resistance in petunia.

    PubMed

    Estrada-Melo, Alejandro C; Chao; Reid, Michael S; Jiang, Cai-Zhong

    2015-01-01

    The response of plants to drought stress includes reduced transpiration as stomates close in response to increased abscisic acid (ABA) concentrations. Constitutive overexpression of 9-cis-epoxycarotenoid dioxygenase (NCED), a key enzyme in ABA biosynthesis, increases drought resistance, but causes negative pleiotropic effects on plant growth and development. We overexpressed the tomato NCED (LeNCED1) in petunia plants under the control of a stress-inducible promoter, rd29A. Under water stress, the transgenic plants had increased transcripts of NCED mRNA, elevated leaf ABA concentrations, increased concentrations of proline, and a significant increase in drought resistance. The transgenic plants also displayed the expected decreases in stomatal conductance, transpiration, and photosynthesis. After 14 days without water, the control plants were dead, but the transgenic plants, though wilted, recovered fully when re-watered. Well-watered transgenic plants grew like non-transformed control plants and there was no effect of the transgene on seed dormancy.

  9. Overexpression of an ABA biosynthesis gene using a stress-inducible promoter enhances drought resistance in petunia

    PubMed Central

    Estrada-Melo, Alejandro C; Chao; Reid, Michael S; Jiang, Cai-Zhong

    2015-01-01

    The response of plants to drought stress includes reduced transpiration as stomates close in response to increased abscisic acid (ABA) concentrations. Constitutive overexpression of 9-cis-epoxycarotenoid dioxygenase (NCED), a key enzyme in ABA biosynthesis, increases drought resistance, but causes negative pleiotropic effects on plant growth and development. We overexpressed the tomato NCED (LeNCED1) in petunia plants under the control of a stress-inducible promoter, rd29A. Under water stress, the transgenic plants had increased transcripts of NCED mRNA, elevated leaf ABA concentrations, increased concentrations of proline, and a significant increase in drought resistance. The transgenic plants also displayed the expected decreases in stomatal conductance, transpiration, and photosynthesis. After 14 days without water, the control plants were dead, but the transgenic plants, though wilted, recovered fully when re-watered. Well-watered transgenic plants grew like non-transformed control plants and there was no effect of the transgene on seed dormancy. PMID:26504568

  10. FABP4 plasma levels are increased in familial combined hyperlipidemia

    PubMed Central

    Cabré, Anna; Lázaro, Iolanda; Cofán, Montserrat; Jarauta, Estibaliz; Plana, Núria; Garcia-Otín, Angel L.; Ascaso, Juan F.; Ferré, Raimón; Civeira, Fernando; Ros, Emilio; Masana, Lluís

    2010-01-01

    The lipid profile of familial combined hyperlipidemia (FCHL) shares some characteristics with atherogenic dyslipidemia seen in diabetes, metabolic syndrome, and obesity. Adipocyte fatty acid-binding protein 4 (FABP4) appears to be a determinant of atherogenic dyslipidemia. We examined relationships between FABP4 plasma concentrations, dyslipidemia, and metabolic variables in patients with FCHL. We studied 273 unrelated FCHL patients and 118 control subjects. FABP4 was higher in FCHL than controls, with mean levels of 21.8 (10.1) μg/l and 19.2 (9.2) μg/l, respectively (adjusted P= 0.012). In FCHL, FABP4 correlated to body mass index (BMI), waist circumference, insulin levels, and homeostasis model assessment (HOMA) index (all P< 0.05), but not to lipid levels, whereas in obese patients, FABP4 correlated to triglyceride levels (r = 0.303, P= 0.014) and very low density lipoprotein size (r = 0.502, P = 0.001), as determined by nuclear magnetic resonance. Associations of FABP4 with BMI and waist circumference, but not with insulin levels, persisted in this subgroup. Plasma FABP4 does not influence the lipid phenotype of FCHL. In a small subgroup of obese FCHL, FABP4 levels were associated with triglyceride-rich lipoproteins independent of insulin resistance. These results support a hyperlipidemic mechanism of FCHL different from similar metabolic conditions where fat mass is strongly related to FABP4 and hypertriglyceridemia. PMID:20388924

  11. Hip Osteonecrosis Is Associated with Increased Plasma IL-33 Level

    PubMed Central

    Ma, Jinhui; Guo, Wanshou; Li, Zirong; Li, Shirui; Wang, Peng

    2017-01-01

    The recently discovered IL-33 as an IL-1 cytokine family member has been proved to be specifically released from osteonecrotic bones. We aimed to investigate the potential role of IL-33 in the development of osteonecrosis of femoral head (ONFH). Forty patients diagnosed with ONFH and forty age-, sex-, and body mass index- (BMI-) matched healthy subjects were included in this prospective study between March 2016 and September 2016. A commercially available ELISA kit was used to test the level of plasma IL-33. The IL-33 levels were compared among different ARCO stages, CJFH types, and etiology groups. Plasma IL-33 levels were significantly higher in the ONFH patients than that in the control subjects. The levels of IL-33 did not differ significantly among the ONFH patients with different ARCO stages. The IL-33 levels of patients with CJFH type L3 were significantly higher than that of patients with types L1 and L2. No significant differences were observed in IL-33 levels between steroid-induced, alcohol-induced, and idiopathic patients. Our findings seem to indicate that IL-33 effects may be detrimental during ONFH, which appeared to be associated with the prognosis of ONFH. The IL-33 deserves particular attention in the pathogenesis of ONFH. PMID:28167850

  12. Quantitative Proteomic Analyses Identify ABA-Related Proteins and Signal Pathways in Maize Leaves under Drought Conditions.

    PubMed

    Zhao, Yulong; Wang, Yankai; Yang, Hao; Wang, Wei; Wu, Jianyu; Hu, Xiuli

    2016-01-01

    Drought stress is one of major factors resulting in maize yield loss. The roles of abscisic acid (ABA) have been widely studied in crops in response to drought stress. However, more attention is needed to identify key ABA-related proteins and also gain deeper molecular insights about drought stress in maize. Based on this need, the physiology and proteomics of the ABA-deficient maize mutant vp5 and its wild-type Vp5 under drought stress were examined and analyzed. Malondialdehyde content increased and quantum efficiency of photosystem II decreased under drought stress in both genotypes. However, the magnitude of the increase or decrease was significantly higher in vp5 than in Vp5. A total of 7051 proteins with overlapping expression patterns among three replicates in the two genotypes were identified by Multiplex run iTRAQ-based quantitative proteomic and liquid chromatography-tandem mass spectrometry methods, of which the expression of only 150 proteins (130 in Vp5, 27 in vp5) showed changes of at least 1.5-fold under drought stress. Among the 150 proteins, 67 and 60 proteins were up-regulated and down-regulated by drought stress in an ABA-dependent way, respectively. ABA was found to play active roles in regulating signaling pathways related to photosynthesis, oxidative phosphorylation (mainly related to ATP synthesis), and glutathione metabolism (involved in antioxidative reaction) in the maize response to drought stress. Our results provide an extensive dataset of ABA-dependent, drought-regulated proteins in maize plants, which may help to elucidate the underlying mechanisms of ABA-enhanced tolerance to drought stress in maize.

  13. Quantitative Proteomic Analyses Identify ABA-Related Proteins and Signal Pathways in Maize Leaves under Drought Conditions

    PubMed Central

    Zhao, Yulong; Wang, Yankai; Yang, Hao; Wang, Wei; Wu, Jianyu; Hu, Xiuli

    2016-01-01

    Drought stress is one of major factors resulting in maize yield loss. The roles of abscisic acid (ABA) have been widely studied in crops in response to drought stress. However, more attention is needed to identify key ABA-related proteins and also gain deeper molecular insights about drought stress in maize. Based on this need, the physiology and proteomics of the ABA-deficient maize mutant vp5 and its wild-type Vp5 under drought stress were examined and analyzed. Malondialdehyde content increased and quantum efficiency of photosystem II decreased under drought stress in both genotypes. However, the magnitude of the increase or decrease was significantly higher in vp5 than in Vp5. A total of 7051 proteins with overlapping expression patterns among three replicates in the two genotypes were identified by Multiplex run iTRAQ-based quantitative proteomic and liquid chromatography-tandem mass spectrometry methods, of which the expression of only 150 proteins (130 in Vp5, 27 in vp5) showed changes of at least 1.5-fold under drought stress. Among the 150 proteins, 67 and 60 proteins were up-regulated and down-regulated by drought stress in an ABA-dependent way, respectively. ABA was found to play active roles in regulating signaling pathways related to photosynthesis, oxidative phosphorylation (mainly related to ATP synthesis), and glutathione metabolism (involved in antioxidative reaction) in the maize response to drought stress. Our results provide an extensive dataset of ABA-dependent, drought-regulated proteins in maize plants, which may help to elucidate the underlying mechanisms of ABA-enhanced tolerance to drought stress in maize. PMID:28008332

  14. Ocean acidification increases fatty acids levels of larval fish.

    PubMed

    Díaz-Gil, Carlos; Catalán, Ignacio A; Palmer, Miquel; Faulk, Cynthia K; Fuiman, Lee A

    2015-07-01

    Rising levels of anthropogenic carbon dioxide in the atmosphere are acidifying the oceans and producing diverse and important effects on marine ecosystems, including the production of fatty acids (FAs) by primary producers and their transfer through food webs. FAs, particularly essential FAs, are necessary for normal structure and function in animals and influence composition and trophic structure of marine food webs. To test the effect of ocean acidification (OA) on the FA composition of fish, we conducted a replicated experiment in which larvae of the marine fish red drum (Sciaenops ocellatus) were reared under a climate change scenario of elevated CO2 levels (2100 µatm) and under current control levels (400 µatm). We found significantly higher whole-body levels of FAs, including nine of the 11 essential FAs, and altered relative proportions of FAs in the larvae reared under higher levels of CO2. Consequences of this effect of OA could include alterations in performance and survival of fish larvae and transfer of FAs through food webs.

  15. Ocean acidification increases fatty acids levels of larval fish

    PubMed Central

    Díaz-Gil, Carlos; Catalán, Ignacio A.; Palmer, Miquel; Faulk, Cynthia K.; Fuiman, Lee A.

    2015-01-01

    Rising levels of anthropogenic carbon dioxide in the atmosphere are acidifying the oceans and producing diverse and important effects on marine ecosystems, including the production of fatty acids (FAs) by primary producers and their transfer through food webs. FAs, particularly essential FAs, are necessary for normal structure and function in animals and influence composition and trophic structure of marine food webs. To test the effect of ocean acidification (OA) on the FA composition of fish, we conducted a replicated experiment in which larvae of the marine fish red drum (Sciaenops ocellatus) were reared under a climate change scenario of elevated CO2 levels (2100 µatm) and under current control levels (400 µatm). We found significantly higher whole-body levels of FAs, including nine of the 11 essential FAs, and altered relative proportions of FAs in the larvae reared under higher levels of CO2. Consequences of this effect of OA could include alterations in performance and survival of fish larvae and transfer of FAs through food webs. PMID:26179801

  16. Pyoderma gangrenosum with increased levels of serum cytokines.

    PubMed

    Kozono, Kana; Nakahara, Takeshi; Kikuchi, Satoko; Itoh, Eriko; Kido-Nakahara, Makiko; Furue, Masutaka

    2015-12-01

    A 66-year-old woman presented after an episode of accidental trauma with a painful ulcer on her scalp which rapidly enlarged in size, accompanied by central necrosis and undermining ulceration. The patient's past history was negative for underlying systemic disease, although she had had a similar post-traumatic intractable leg ulcer 3 years prior, which was unresponsive to surgical management but successfully treated with systemic steroids. A biopsied specimen from the scalp showed marked neutrophilic infiltrates in the dermis, compatible with a diagnosis of pyoderma gangrenosum (PG). The large ulcerative lesion responded very well to oral steroid therapy, showing rapid epithelialization. Serum levels of granulocyte colony-stimulating factor and interleukin-6 were significantly elevated prior to treatment, with decrease to normal levels after treatment. Serum tumor necrosis factor (TNF)-α and granulocyte macrophage colony-stimulating factor levels were within normal limits. The significance and pathogenic role of cytokine burst in PG is reviewed and discussed.

  17. Nitric oxide and ABA in the control of plant function.

    PubMed

    Hancock, J T; Neill, S J; Wilson, I D

    2011-11-01

    Abscisic acid (ABA) and nitric oxide (NO) are both extremely important signalling molecules employed by plants to control many aspects of physiology. ABA has been extensively studied in the mechanisms which control stomatal movement as well as in seed dormancy and germination and plant development. The addition of either ABA or NO to plant cells is known to instigate the actions of many signal transduction components. Both may have an influence on the phosphorylation of proteins in cells mediated by effects on protein kinases and phosphatases, as well as recruiting a wide range of other signal transduction molecules to mediate the final effects. Both ABA and NO may also lead to the regulation of gene expression. However, it is becoming more apparent that NO may be acting downstream of ABA, with such action being mediated by reactive oxygen species such as hydrogen peroxide in some cases. However not all ABA responses require the action of NO. Here, examples of where ABA and NO have been put together into the same signal transduction pathways are discussed.

  18. Pepper CaREL1, a ubiquitin E3 ligase, regulates drought tolerance via the ABA-signalling pathway.

    PubMed

    Lim, Chae Woo; Park, Chanmi; Kim, Jung-Hyun; Joo, Hyunhee; Hong, Eunji; Lee, Sung Chul

    2017-03-28

    Drought stress conditions in soil or air hinder plant growth and development. Here, we report that the hot pepper (C apsicum a nnuum) RING type E3 Ligase 1 gene (CaREL1) is essential to the drought stress response. CaREL1 encodes a cytoplasmic- and nuclear-localized protein with E3 ligase activity. CaREL1 expression was induced by abscisic acid (ABA) and drought. CaREL1 contains a C3H2C3-type RING finger motif, which functions in ubiquitination of the target protein. We used CaREL1-silenced pepper plants and CaREL1-overexpressing (OX) transgenic Arabidopsis plants to evaluate the in vivo function of CaREL1 in response to drought stress and ABA treatment. CaREL1-silenced pepper plants displayed a drought-tolerant phenotype characterized by ABA hypersensitivity. In contrast, CaREL1-OX plants exhibited ABA hyposensitivity during the germination, seedling, and adult stages. In addition, plant growth was severely impaired under drought stress conditions, via a high level of transpirational water loss and decreased stomatal closure. Quantitative RT-PCR analyses revealed that ABA-related drought stress responsive genes were more weakly expressed in CaREL1-OX plants than in wild-type plants, indicating that CaREL1 functions in the drought stress response via the ABA-signalling pathway. Taken together, our results indicate that CaREL1 functions as a negative regulator of ABA-mediated drought stress tolerance.

  19. An ABA-regulated and Golgi-localized protein phosphatase controls water loss during leaf senescence in Arabidopsis.

    PubMed

    Zhang, Kewei; Xia, Xiuying; Zhang, Yanyan; Gan, Su-Sheng

    2012-02-01

    It is known that a senescing leaf loses water faster than a non-senescing leaf and that ABA has an important role in promoting leaf senescence. However, questions such as why water loss is faster, how water loss is regulated, and how ABA functions in leaf senescence are not well understood. Here we report on the identification and functional analysis of a leaf senescence associated gene called SAG113. The RNA blot and GUS reporter analyses all show that SAG113 is expressed in senescing leaves and is induced by ABA in Arabidopsis. The SAG113 expression levels are significantly reduced in aba2 and abi4 mutants. A GFP fusion protein analysis revealed that SAG113 protein is localized in the Golgi apparatus. SAG113 encodes a protein phosphatase that belongs to the PP2C family and is able to functionally complement a yeast PP2C-deficient mutant TM126 (ptc1Δ). Leaf senescence is delayed in the SAG113 knockout mutant compared with that in the wild type, stomatal movement in the senescing leaves of SAG113 knockouts is more sensitive to ABA than that of the wild type, and the rate of water loss in senescing leaves of SAG113 knockouts is significantly reduced. In contrast, inducible over-expression of SAG113 results in a lower sensitivity of stomatal movement to ABA treatment, more rapid water loss, and precocious leaf senescence. No other aspects of growth and development, including seed germination, were observed. These findings suggest that SAG113, a negative regulator of ABA signal transduction, is specifically involved in the control of water loss during leaf senescence.

  20. A 14-3-3 Family Protein from Wild Soybean (Glycine Soja) Regulates ABA Sensitivity in Arabidopsis.

    PubMed

    Sun, Xiaoli; Sun, Mingzhe; Jia, Bowei; Chen, Chao; Qin, Zhiwei; Yang, Kejun; Shen, Yang; Meiping, Zhang; Mingyang, Cong; Zhu, Yanming

    2015-01-01

    It is widely accepted that the 14-3-3 family proteins are key regulators of multiple stress signal transduction cascades. By conducting genome-wide analysis, researchers have identified the soybean 14-3-3 family proteins; however, until now, there is still no direct genetic evidence showing the involvement of soybean 14-3-3s in ABA responses. Hence, in this study, based on the latest Glycine max genome on Phytozome v10.3, we initially analyzed the evolutionary relationship, genome organization, gene structure and duplication, and three-dimensional structure of soybean 14-3-3 family proteins systematically. Our results suggested that soybean 14-3-3 family was highly evolutionary conserved and possessed segmental duplication in evolution. Then, based on our previous functional characterization of a Glycine soja 14-3-3 protein GsGF14o in drought stress responses, we further investigated the expression characteristics of GsGF14o in detail, and demonstrated its positive roles in ABA sensitivity. Quantitative real-time PCR analyses in Glycine soja seedlings and GUS activity assays in PGsGF14O:GUS transgenic Arabidopsis showed that GsGF14o expression was moderately and rapidly induced by ABA treatment. As expected, GsGF14o overexpression in Arabidopsis augmented the ABA inhibition of seed germination and seedling growth, promoted the ABA induced stomata closure, and up-regulated the expression levels of ABA induced genes. Moreover, through yeast two hybrid analyses, we further demonstrated that GsGF14o physically interacted with the AREB/ABF transcription factors in yeast cells. Taken together, results presented in this study strongly suggested that GsGF14o played an important role in regulation of ABA sensitivity in Arabidopsis.

  1. RhHB1 mediates the antagonism of gibberellins to ABA and ethylene during rose (Rosa hybrida) petal senescence.

    PubMed

    Lü, Peitao; Zhang, Changqing; Liu, Jitao; Liu, Xiaowei; Jiang, Guimei; Jiang, Xinqiang; Khan, Muhammad Ali; Wang, Liangsheng; Hong, Bo; Gao, Junping

    2014-05-01

    Rose (Rosa hybrida) is one of the most important ornamental plants worldwide; however, senescence of its petals terminates the ornamental value of the flower, resulting in major economic loss. It is known that the hormones abscisic acid (ABA) and ethylene promote petal senescence, while gibberellins (GAs) delay the process. However, the molecular mechanisms underlying the antagonistic effects amongst plant hormones during petal senescence are still unclear. Here we isolated RhHB1, a homeodomain-leucine zipper I transcription factor gene, from rose flowers. Quantitative RT-PCR and GUS reporter analyses showed that RhHB1 was strongly expressed in senescing petals, and its expression was induced by ABA or ethylene in petals. ABA or ethylene treatment clearly accelerated rose petal senescence, while application of the gibberellin GA3 delayed the process. However, silencing of RhHB1 delayed the ABA- or ethylene-mediated senescence, and resulted in higher petal anthocyanin levels and lower expression of RhSAG12. Moreover, treatment with paclobutrazol, an inhibitor of GA biosynthesis, repressed these delays. In addition, silencing of RhHB1 blocked the ABA- or ethylene-induced reduction in expression of the GA20 oxidase encoded by RhGA20ox1, a gene in the GA biosynthetic pathway. Furthermore, RhHB1 directly binds to the RhGA20ox1 promoter, and silencing of RhGA20ox1 promoted petal senescence. Eight senescence-related genes showed substantial differences in expression in petals after treatment with GA3 or paclobutrazol. These results suggest that RhHB1 mediates the antagonistic effect of GAs on ABA and ethylene during rose petal senescence, and that the promotion of petal senescence by ABA or ethylene operates through an RhHB1-RhGA20ox1 regulatory checkpoint.

  2. Hormone profiling and transcription analysis reveal a major role of ABA in tomato salt tolerance.

    PubMed

    Yang, Rongchao; Yang, Ting; Zhang, Haijun; Qi, Yan; Xing, Yanxia; Zhang, Na; Li, Ren; Weeda, Sarah; Ren, Shuxin; Ouyang, Bo; Guo, Yang-Dong

    2014-04-01

    The response and adaptation of plants to different environmental stresses are of great interest as they provide the key to understanding the mechanisms underlying stress tolerance. In this study, the changing patterns of four endogenous hormones and various physiological and biochemical parameters of both a salt-tolerant (LA2711) and a salt-sensitive (ZS-5) tomato cultivar were examined under salt stress and non-stress conditions. Additionally, the transcription of key genes in the abscisic acid (ABA) biosynthesis and metabolism were analyzed at different time points. The results indicated that gene expression responsible for ABA biosynthesis and metabolism coincided with the hormone level, and SlNCED1 and SlCYP707A3 may play major roles in the process. LA2711 performed superior to ZS-5 on various parameters, including seed germination, Na(+) compartmentation, selective absorption of K(+), and antioxidant enzymes activity. The difference in salt tolerance between the two genotypes could be attributed to the different levels of ABA due to differences in gene expression of key genes in ABA biosynthesis and metabolism. Although gibberellin, cytokinin and auxin were involved, our results indicated that ABA signaling plays a major role in tomato salt tolerance. As compared to ZS-5, LA2711 had a higher capability to selectively absorb and redistribute K(+) and a higher tolerance to Na(+) in young leaves, which may be the main physiological mechanisms of salt tolerance.

  3. BnSIP1-1, a Trihelix Family Gene, Mediates Abiotic Stress Tolerance and ABA Signaling in Brassica napus

    PubMed Central

    Luo, Junling; Tang, Shaohua; Mei, Fengling; Peng, Xiaojue; Li, Jun; Li, Xiaofei; Yan, Xiaohong; Zeng, Xinhua; Liu, Fang; Wu, Yuhua; Wu, Gang

    2017-01-01

    The trihelix family genes have important functions in light-relevant and other developmental processes, but their roles in response to adverse environment are largely unclear. In this study, we identified a new gene, BnSIP1-1, which fell in the SIP1 (6b INTERACTING PROTEIN1) clade of the trihelix family with two trihelix DNA binding domains and a fourth amphipathic α-helix. BnSIP1-1 protein specifically targeted to the nucleus, and its expression can be induced by abscisic acid (ABA) and different stresses. Overexpression of BnSIP1-1 improved seed germination under osmotic pressure, salt, and ABA treatments. Moreover, BnSIP1-1 decreased the susceptibility of transgenic seedlings to osmotic pressure and ABA treatments, whereas there was no difference under salt stress between the transgenic and wild-type seedlings. ABA level in the transgenic seedlings leaves was higher than those in the control plants under normal condition. Under exogenous ABA treatment and mannitol stress, the accumulation of ABA in the transgenic plants was higher than that in the control plants; while under salt stress, the difference of ABA content before treatment was gradually smaller with the prolongation of salt treatment time, then after 24 h of treatment the ABA level was similar in transgenic and wild-type plants. The transcription levels of several general stress marker genes (BnRD29A, BnERD15, and BnLEA1) were higher in the transgenic plants than the wild-type plants, whereas salt-responsive genes (BnSOS1, BnNHX1, and BnHKT) were not significantly different or even reduced compared with the wild-type plants, which indicated that BnSIP1-1 specifically exerted different regulatory mechanisms on the osmotic- and salt-response pathways in seedling period. Overall, these findings suggested that BnSIP1-1 played roles in ABA synthesis and signaling, salt and osmotic stress response. To date, information about the involvement of the Brassica napus trihelix gene in abiotic response is scarce

  4. Increased Cortisol and Cortisone Levels in Overweight Children

    PubMed Central

    Chu, Lanling; Sheng, Kangwei; Liu, Ping; Ye, Kan; Wang, Yu; Li, Chen; Kang, Xuejun; Song, Yuan

    2017-01-01

    Background It has been unclear whether relatively high cortisol and cortisone levels are related to overweight in childhood, parental body mass index (BMI), and family dietary habits. The aim of this study was to compare cortisol and cortisone levels in urine and saliva from overweight and normal children, as well as correlations between children’s BMI, parental BMI and family dietary behavior questionnaire score (QS). Material/Methods We analyzed the data from 52 overweight children and 53 age- and sex-matched normal-weight children aged 4–5 years. The concentrations of salivary cortisol (SF), salivary cortisone (SE), urinary cortisol (UF) and urinary cortisone (UE) were measured using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The family dietary behavior QS was answered by the parent mainly responsible for the family diet. Results Average cortisol and cortisone levels were significantly higher in overweight children. There was no significant difference in the ratio of cortisol to cortisone (Rcc) and the marker of 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2) activities. The results displayed correlations among cortisol, cortisone, and Rcc. Positive correlations were weak-to-moderate between BMI and SF, SE, UF, and UE. There were correlations between BMI and maternal BMI (mBMI), and BMI was significantly associated with QS. Conclusions Our results suggest that cortisol and cortisone levels are associated with overweight in children, but the 11β-HSD2 activities showed no significant differences. Unhealthy family diet was associated with higher BMI, UF, and UE, and families with maternal overweight or obesity had a higher prevalence of children’s overweight or obesity. PMID:28179618

  5. Increase of inherent protection level in spent nuclear fuel

    SciTech Connect

    Krasnobaev, A.; Kryuchkov, E.; Glebov, V.

    2006-07-01

    The paper is devoted to upgrading inherent proliferation protection of fissionable nuclear materials (FNM). Some possibilities were investigated to form high radiation barrier inside spent fuel assemblies (SFA) discharged from power reactors of VVER-1000 type and research reactors of IRT type. The radiation barrier is estimated in the terms of rate of equivalent dose (RED) at 30-cm distance from SFA. The values of RED were calculated with application of the computer code package SCALE 4.3. The paper considers the criteria adopted for estimation of FNM proliferation resistance. The paper presents numerical results on a component-wise analysis of the radiation barrier in SFA from reactors of VVER-1000 and IRT type and on capability of various radionuclides to prolong action of the radiation barrier. Isotopic admixtures were selected and amounts of these admixtures were evaluated for significant prolongation of the radiation barrier action at the levels of the radiation standards used for estimation of FNM proliferation resistance. The paper considers vulnerability of the radiation barriers in respect to thermal processing of spent fuel. (authors)

  6. Characterization of the ABA signal transduction pathway in Vitis vinifera.

    PubMed

    Boneh, Uri; Biton, Iris; Schwartz, Amnon; Ben-Ari, Giora

    2012-05-01

    The plant hormone abscisic acid (ABA) regulates many key processes in plants including the response to abiotic stress. ABA signal transduction consists of a double-negative regulatory mechanism, whereby ABA-bound PYR/RCARs inhibit PP2C activity, and PP2Cs inactivate SnRK2s. We studied and analyzed the various genes participating in the ABA signaling cascade of the grape (Vitis vinifera). The grape ABA signal transduction consists of at least six SnRK2s. Yeast two-hybrid system was used to test direct interactions between core components of grape ABA signal transduction. We found that a total of forty eight interactions can occur between the various components. Exogenous abscisic acid (ABA) and abiotic stresses such as drought, high salt concentration and cold, were applied to vines growing in a hydroponic system. These stresses regulated the expression of various grape SnRK2s as well as ABFs in leaves and roots. Based on the interactions between SnRK2s and its targets and the expression pattern, we suggest that VvSnRK2.1 and VvSnRK2.6, can be considered the major VvSnRK2 candidates involved in the stomata response to abiotic stress. Furthermore, we found that the expression pattern of the two grape ABF genes indicates organ specificity of these genes. The key role of ABA signaling in response to abiotic stresses makes the genes involve in this signaling potential candidates for manipulation in programs designed to improve fruit tree performance in extreme environments.

  7. Accounting for sap flow from different parts of the root system improves the prediction of xylem ABA concentration in plants grown with heterogeneous soil moisture

    PubMed Central

    Dodd, Ian C.; Egea, Gregorio; Davies, William J.

    2008-01-01

    When soil moisture is heterogeneous, sap flow from, and ABA status of, different parts of the root system impact on leaf xylem ABA concentration ([X-ABA]leaf). The robustness of a model for predicting [X-ABA]leaf was assessed. ‘Two root-one shoot’ grafted sunflower (Helianthus annuus L.) plants received either deficit irrigation (DI, each root system received the same irrigation volumes) or partial rootzone drying (PRD, only one root system was watered and the other dried the soil). Irrespective of whether relative sap flow was assessed using sap flow sensors in vivo or by pressurization of de-topped roots, each root system contributed similarly to total sap flow during DI, while sap flow from roots in drying soil declined linearly with soil water potential (Ψsoil) during PRD. Although Ψsoil of the irrigated pot determined the threshold Ψsoil at which sap flow from roots in drying soil decreased, the slope of this decrease was independent of the wet pot Ψsoil. Irrespective of whether sap was collected from the wet or dry root system of PRD plants, or a DI plant, root xylem ABA concentration increased as Ψsoil declined. The model, which weighted ABA contributions of each root system according to the sap flow from each, almost perfectly explained [X-ABA] immediately above the graft union. That the model overestimated measured [X-ABA]leaf may result from changes in [X-ABA] along the transport pathway or an artefact of collecting xylem sap from detached leaves. The implications of declining sap flow through partially dry roots during PRD for the control of stomatal behaviour and irrigation scheduling are discussed. PMID:18940933

  8. Accounting for sap flow from different parts of the root system improves the prediction of xylem ABA concentration in plants grown with heterogeneous soil moisture.

    PubMed

    Dodd, Ian C; Egea, Gregorio; Davies, William J

    2008-01-01

    When soil moisture is heterogeneous, sap flow from, and ABA status of, different parts of the root system impact on leaf xylem ABA concentration ([X-ABA]leaf). The robustness of a model for predicting [X-ABA]leaf was assessed. 'Two root-one shoot' grafted sunflower (Helianthus annuus L.) plants received either deficit irrigation (DI, each root system received the same irrigation volumes) or partial rootzone drying (PRD, only one root system was watered and the other dried the soil). Irrespective of whether relative sap flow was assessed using sap flow sensors in vivo or by pressurization of de-topped roots, each root system contributed similarly to total sap flow during DI, while sap flow from roots in drying soil declined linearly with soil water potential (Psisoil) during PRD. Although Psisoil of the irrigated pot determined the threshold Psisoil at which sap flow from roots in drying soil decreased, the slope of this decrease was independent of the wet pot Psisoil. Irrespective of whether sap was collected from the wet or dry root system of PRD plants, or a DI plant, root xylem ABA concentration increased as Psisoil declined. The model, which weighted ABA contributions of each root system according to the sap flow from each, almost perfectly explained [X-ABA] immediately above the graft union. That the model overestimated measured [X-ABA]leaf may result from changes in [X-ABA] along the transport pathway or an artefact of collecting xylem sap from detached leaves. The implications of declining sap flow through partially dry roots during PRD for the control of stomatal behaviour and irrigation scheduling are discussed.

  9. Endogenous Levels of Abscisic Acid and Decanoic Acid in Dutch Iris Bulbs and the Influence of Abscisic Acid and Decanoic Acid on Iris Meristems Cultured In Vitro1

    PubMed Central

    Doss, Robert P.; Kimura, Yosh; Christian, James K.

    1983-01-01

    Abscisic acid (ABA) and decanoic acid inhibited shoot elongation and floral development of Dutch iris (Iris hollandica Hoog. cv Ideal) meristems cultured in vitro. No synergism with respect to inhibition of leaf growth between ABA and decanoic acid was observed. With monthly harvest dates, from July 10, 1981 to October 10, 1981, there was a progressive decrease in endogenous level of free ABA in `Ideal' iris bulbs. Bulbs subjected to a full set of the usual preplanting storage conditions flowered, on average, 46 days after planting versus 194 days after planting for bulbs planted directly after harvest. ABA levels at harvest were 4- to 5-fold those after the preplanting storage treatment. In general, ABA levels did not correlate well with the length of time from planting until flowering of iris bulbs. Endogenous decanoic acid levels did not follow any pattern with respect to harvest date or postharvest treatment. After the postharvest high temperature treatment, there was about a 3-fold increase in nonscale decanoic acid concentration. Decanoic acid levels, in nonscale tissue, remained high after each of the other postharvest treatments. It is concluded that there is no good evidence to support the contention that either ABA or decanoic acid is directly involved in iris bulb dormancy. PMID:16663072

  10. Increased carbon tetrachloride hepatotoxicity after low-level ethanol consumption.

    PubMed

    Strubelt, O; Obermeier, F; Siegers, C P; Vöpel, M

    1978-07-01

    Male rats provided with a 5 or 15% (v/v) ethanol solution as the sole source of fluid consumed ethanol at a rate of 11.4 or 24.9% of total calories (4.2 or 8.3 g/kg daily). After ethanol consumption lasting 1, 2 and 3 weeks the hepatotoxicity of CCl4 (0.1 ml/kg i.p.) was elevated by determination of serum activities of glutamic-oxaloacetic transaminase (GOT), glutamic-pyruvic transaminase ( GPT), sorbitol dehydrogenase (SDH) and histological investigations. Carbon tetrachloride (CCl4)-induced liver damage was significantly greater in rats provided with ethanol than in the tap-water consuming controls. This potentiation of CCl4 hepatotoxicicty was fully developed already after a 1-week exposition to ethanol and was greater in the 15% than in the 5% ethanol group. Ethanol alone did not influence serum enzyme activities but increased microsomal aniline hydroxylation. There was, however, no clear-cut parallelism between potentiation of CCl4 hepatotoxicity and activation of aniline hydroxylation.

  11. Multiple impacts of the plant growth-promoting rhizobacterium Variovorax paradoxus 5C-2 on nutrient and ABA relations of Pisum sativum

    PubMed Central

    Dodd, Ian C.

    2012-01-01

    Resolving the physiological mechanisms by which rhizobacteria enhance plant growth is difficult, since many such bacteria contain multiple plant growth-promoting properties. To understand further how the 1-aminocyclopropane-1-carboxylate (ACC) deaminase (ACCd)-containing rhizobacterium Variovorax paradoxus 5C-2 affects plant growth, the flows and partitioning of mineral nutrients and abscisic acid (ABA) and ABA metabolism were studied in pea (Pisum sativum) plants following rhizosphere bacterial inoculation. Although root architecture was not affected, inoculation increased root and shoot biomass, and stomatal conductance, by 20, 15, and 24%, respectively, and increased N, P, K, Ca, and Mg uptake by 16, 81, 50, 46, and 58%, respectively. P deposition in inoculated plant roots was 4.9 times higher than that in uninoculated controls. Rhizobacterial inoculation increased root to shoot xylem flows and shoot to root phloem flows of K by 1.8- and 2.1-fold, respectively. In control plants, major sinks for K deposition were the roots and upper shoot (43% and 49% of total uptake, respectively), while rhizobacterial inoculation increased K distribution to the lower shoot at the expense of other compartments (xylem, phloem, and upper shoot). Despite being unable to metabolize ABA in vitro, V. paradoxus 5C-2 decreased root ABA concentrations and accumulation by 40–60%. Although inoculation decreased xylem ABA flows, phloem ABA flows increased. Whether bacterial ACCd attenuates root to shoot ABA signalling requires further investigation, since ABA is critical to maintain growth of droughted plants, and ACCd-containing organisms have been advocated as a means of minimizing growth inhibition of plants in drying soil. PMID:23136167

  12. Multiple impacts of the plant growth-promoting rhizobacterium Variovorax paradoxus 5C-2 on nutrient and ABA relations of Pisum sativum.

    PubMed

    Jiang, Fan; Chen, Lin; Belimov, Andrey A; Shaposhnikov, Alexander I; Gong, Fan; Meng, Xu; Hartung, Wolfram; Jeschke, Dieter W; Davies, William J; Dodd, Ian C

    2012-11-01

    Resolving the physiological mechanisms by which rhizobacteria enhance plant growth is difficult, since many such bacteria contain multiple plant growth-promoting properties. To understand further how the 1-aminocyclopropane-1-carboxylate (ACC) deaminase (ACCd)-containing rhizobacterium Variovorax paradoxus 5C-2 affects plant growth, the flows and partitioning of mineral nutrients and abscisic acid (ABA) and ABA metabolism were studied in pea (Pisum sativum) plants following rhizosphere bacterial inoculation. Although root architecture was not affected, inoculation increased root and shoot biomass, and stomatal conductance, by 20, 15, and 24%, respectively, and increased N, P, K, Ca, and Mg uptake by 16, 81, 50, 46, and 58%, respectively. P deposition in inoculated plant roots was 4.9 times higher than that in uninoculated controls. Rhizobacterial inoculation increased root to shoot xylem flows and shoot to root phloem flows of K by 1.8- and 2.1-fold, respectively. In control plants, major sinks for K deposition were the roots and upper shoot (43% and 49% of total uptake, respectively), while rhizobacterial inoculation increased K distribution to the lower shoot at the expense of other compartments (xylem, phloem, and upper shoot). Despite being unable to metabolize ABA in vitro, V. paradoxus 5C-2 decreased root ABA concentrations and accumulation by 40-60%. Although inoculation decreased xylem ABA flows, phloem ABA flows increased. Whether bacterial ACCd attenuates root to shoot ABA signalling requires further investigation, since ABA is critical to maintain growth of droughted plants, and ACCd-containing organisms have been advocated as a means of minimizing growth inhibition of plants in drying soil.

  13. Immunolocalization of IAA and ABA in roots and needles of radiata pine (Pinus radiata) during drought and rewatering.

    PubMed

    De Diego, N; Rodríguez, J L; Dodd, I C; Pérez-Alfocea, F; Moncaleán, P; Lacuesta, M

    2013-05-01

    Anatomical, physiological and phytohormonal changes involved in drought tolerance were examined in different Pinus radiata D. Don breeds subjected to soil drying and rewatering. Breeds with the smallest stomatal chamber size had the lowest transpiration rate and the highest intrinsic water-use efficiency. Xylem cell size was positively correlated with leaf hydraulic conductance and needle indole-3-acetic acid (IAA) concentrations, whereas transpiration rate was negatively correlated with needle abscisic acid (ABA) levels. Since these two phytohormones seem important in regulating the P. radiata drought response, they were simultaneously immunolocalized in roots and needles of the most tolerant breed (P. radiata var. radiata × var. cedrosensis) during two sequential drought cycles and after rewatering. During drought, IAA was unequally distributed into the pointed area of the needle cross-section and mainly located in mesophyll and vascular tissue cells of needles, possibly inducing needle epinasty, whereas ABA was principally located in guard cells, presumably to elicit stomata closure. In the roots, at the end of the first drought cycle, while strong IAA accumulation was observed in the cortex, ABA levels decreased probably due to translocation to the leaves. Rewatering modified the distribution of both IAA and ABA in the needles, causing an accumulation principally in vascular tissue, with residual concentrations in mesophyll, likely favouring the acclimatization of the plants for further drought cycles. Contrarily, in the roots IAA and ABA were located in the exodermis, a natural barrier that regulates the phytohormone translocation to other plant tissues and hormone losses to the soil solution after rewatering. These results confirm that immunolocalization is an efficient tool to understand the translocation of IAA and ABA in plants subjected to different water stress situations, and clarify their role in regulating physiological responses such as stomata

  14. A balanced JA/ABA status may correlate with adaptation to osmotic stress in Vitis cells.

    PubMed

    Ismail, Ahmed; Seo, Mitsunori; Takebayashi, Yumiko; Kamiya, Yuji; Nick, Peter

    2015-08-01

    Water-related stress is considered a major type of plant stress. Osmotic stress, in particular, represents the common part of all water-related stresses. Therefore, plants have evolved different adaptive mechanisms to cope with osmotic-related disturbances. In the current work, two grapevine cell lines that differ in their osmotic adaptability, Vitis rupestris and Vitis riparia, were investigated under mannitol-induced osmotic stress. To dissect signals that lead to adaptability from those related to sensitivity, osmotic-triggered responses with respect to jasmonic acid (JA) and its active form JA-Ile, abscisic acid (ABA), and stilbene compounds, as well as the expression of their related genes were observed. In addition, the transcript levels of the cellular homeostasis gene NHX1 were examined. The data are discussed with a hypothesis suggesting that a balance of JA and ABA status might correlate with cellular responses, either guiding cells to sensitivity or to progress toward adaptation.

  15. ESCRT-I Component VPS23A Affects ABA Signaling by Recognizing ABA Receptors for Endosomal Degradation.

    PubMed

    Yu, Feifei; Lou, Lijuan; Tian, Miaomiao; Li, Qingliang; Ding, Yanglin; Cao, Xiaoqiang; Wu, Yaorong; Belda-Palazon, Borja; Rodriguez, Pedro L; Yang, Shuhua; Xie, Qi

    2016-12-05

    Recent discovery of PYR/PYL/RCAR-type abscisic acid (ABA) receptors has become one of most significant advances in plant science in the past decade. In mammals, endosomal sorting acts as an important pathway to downregulate different types of receptors, but its role in plant hormone signaling is poorly understood. Here, we report that an ubiquitin E2-like protein, VPS23A, which is a key component of ESCRT-I, negatively regulates ABA signaling. VPS23A has epistatic relationship with PYR/PYL/RCAR-type ABA receptors and disruption of VPS23A enhanced the activity of key kinase OST1 in the ABA signaling pathway under ABA treatment. Moreover, VPS23A interacts with PYR1/PYLs and K63-linked diubiquitin, and PYL4 possesses K63-linked ubiquitinated modification in vivo. Further analysis revealed that VPS23A affects the subcellular localization of PYR1 and the stability of PYL4. Taken together, our results suggest that VPS23A affects PYR1/PYL4 via vacuole-mediated degradation, providing an advanced understanding of both the turnover of ABA receptors and ESCRTs in plant hormone signaling.

  16. Modulation Role of abscisic acid (ABA) on growth, water relations and glycinebetaine metabolism in two maize (Zea mays L.) cultivars under drought stress.

    PubMed

    Zhang, Lixin; Gao, Mei; Hu, Jingjiang; Zhang, Xifeng; Wang, Kai; Ashraf, Muhammad

    2012-01-01

    The role of plant hormone abscisic acid (ABA) in plants under drought stress (DS) is crucial in modulating physiological responses that eventually lead to adaptation to an unfavorable environment; however, the role of this hormone in modulation of glycinebetaine (GB) metabolism in maize particularly at the seedling stage is still poorly understood. Some hydroponic experiments were conducted to investigate the modulation role of ABA on plant growth, water relations and GB metabolism in the leaves of two maize cultivars, Zhengdan 958 (ZD958; drought tolerant), and Jundan 20 (JD20; drought sensitive), subjected to integrated root-zone drought stress (IR-DS) simulated by the addition of polyethylene glycol (PEG, 12% w/v, MW 6000). The IR-DS substantially resulted in increased betaine aldehyde dehydrogenase (BADH) activity and choline content which act as the key enzyme and initial substrate, respectively, in GB biosynthesis. Drought stress also induced accumulation of GB, whereas it caused reduction in leaf relative water content (RWC) and dry matter (DM) in both cultivars. The contents of ABA and GB increased in drought-stressed maize seedlings, but ABA accumulated prior to GB accumulation under the drought treatment. These responses were more predominant in ZD958 than those in JD20. Addition of exogenous ABA and fluridone (Flu) (ABA synthesis inhibitor) applied separately increased and decreased BADH activity, respectively. Abscisic acid application enhanced GB accumulation, leaf RWC and shoot DM production in both cultivars. However, of both maize cultivars, the drought sensitive maize cultivar (JD20) performed relatively better than the other maize cultivar ZD958 under both ABA and Flu application in view of all parameters appraised. It is, therefore, concluded that increase in both BADH activity and choline content possibly resulted in enhancement of GB accumulation under DS. The endogenous ABA was probably involved in the regulation of GB metabolism by regulating

  17. Magnetic oscillation of optical phonon in ABA- and ABC-stacked trilayer graphene

    NASA Astrophysics Data System (ADS)

    Cong, Chunxiao; Jung, Jeil; Cao, Bingchen; Qiu, Caiyu; Shen, Xiaonan; Ferreira, Aires; Adam, Shaffique; Yu, Ting

    2015-06-01

    We present a comparative measurement of the G -peak oscillations of phonon frequency, Raman intensity, and linewidth in the magneto-Raman scattering of optical E2 g phonons in mechanically exfoliated ABA- and ABC-stacked trilayer graphene (TLG). Whereas in ABA-stacked TLG, we observe magnetophonon oscillations consistent with single-bilayer chiral band doublets, the features are flat for ABC-stacked TLG up to magnetic fields of 9 T. This suppression can be attributed to the enhancement of band chirality that compactifies the spectrum of Landau levels and modifies the magnetophonon resonance properties. The drastically different coupling behavior between the electronic excitations and the E2 g phonons in ABA- and ABC-stacked TLG reflects their different electronic band structures and the electronic Landau level transitions and thus can be another way to determine the stacking orders and to probe the stacking-order-dependent electronic structures. In addition, the sensitivity of the magneto-Raman scattering to the particular stacking order in few-layer graphene highlights the important role of interlayer coupling in modifying the optical response properties in van der Waals layered materials.

  18. Arabidopsis cold shock domain protein 2 influences ABA accumulation in seed and negatively regulates germination.

    PubMed

    Sasaki, Kentaro; Kim, Myung-Hee; Kanno, Yuri; Seo, Mitsunori; Kamiya, Yuji; Imai, Ryozo

    2015-01-02

    The cold shock domain (CSD) is the most conserved nucleic acid binding domain and is distributed from bacteria to animals and plants. CSD proteins are RNA chaperones that destabilize RNA secondary structures to regulate stress tolerance and development. AtCSP2 is one of the four CSD proteins in Arabidopsis and is up-regulated in response to cold. Since AtCSP2 negatively regulates freezing tolerance, it was proposed to be a modulator of freezing tolerance during cold acclimation. Here, we examined the function of AtCSP2 in seed germination. We found that AtCSP2-overexpressing lines demonstrated retarded germination as compared with the wild type, with or without stress treatments. The ABA levels in AtCSP2-overexpressing seeds were higher than those in the wild type. In addition, overexpression of AtCSP2 reduced the expression of an ABA catabolic gene (CYP707A2) and gibberellin biosynthesis genes (GA20ox and GA3ox). These results suggest that AtCSP2 negatively regulates seed germination by controlling ABA and GA levels.

  19. CsWRKY46, a WRKY transcription factor from cucumber, confers cold resistance in transgenic-plant by regulating a set of cold-stress responsive genes in an ABA-dependent manner.

    PubMed

    Zhang, Ying; Yu, Hongjun; Yang, Xueyong; Li, Qiang; Ling, Jian; Wang, Hong; Gu, Xingfang; Huang, Sanwen; Jiang, Weijie

    2016-11-01

    Plant WRKY transcription factors are trans-regulatory proteins that are involved in plant immune responses, development and senescence; however, their roles in abiotic stress are still not well understood, especially in the horticultural crop cucumber. In this study, a novel cucumber WRKY gene, CsWRKY46 was cloned and identified, which was up-regulated in response to cold stress and exogenous abscisic acid (ABA) treatment. CsWRKY46 is belonging to group II of the WRKY family, CsWRKY46 was found exclusively in the nucleus, as indicated by a transient expression assay. Yeast one-hybrid assay shown that CsWRKY46 interact with the W-box in the promoter of ABI5. Transgenic Arabidopsis lines over-expressing CsWRKY46, WRK46-OE1 and WRK46-OE5 had higher seedling survival rates upon freezing treatment compared with that of the wild-type. The above over-expression lines also showed much a higher proline accumulation, less electrolyte leakage and lower malondialdehyde (MDA) levels. Furthermore, the CsWRKY46 overexpression lines were hypersensitive to ABA during seed germination, but the seedlings were not. Quantitative RT-PCR analyses revealed that the expression levels of the ABA-responsive transcription factor ABI5 were higher in the WRKY46-OE lines than in wild-type and that the overexpression of CsWRKY46 increased the expression of stress-inducible genes, including RD29A and COR47. Taken together, our results demonstrated that CsWRKY46 from cucumber conferred cold tolerance to transgenic plants and positively regulated the cold signaling pathway in an ABA-dependent manner.

  20. The soybean GmDi19-5 interacts with GmLEA3.1 and increases sensitivity of transgenic plants to abiotic stresses

    PubMed Central

    Feng, Zhi-Juan; Cui, Xiao-Yu; Cui, Xi-Yan; Chen, Ming; Yang, Guang-Xiao; Ma, You-Zhi; He, Guang-Yuan; Xu, Zhao-Shi

    2015-01-01

    Drought-induced (Di19) proteins played important roles in plant growth, development, and abiotic stress responses. In the present study, a total of seven Di19 genes were identified in soybean. Each soybean Di19 gene showed specific responses to salt, drought, oxidative, and ABA stresses based on expression profiles. With a relatively higher transcript level among Di19 members under four stress treatments, GmDi19-5 was selected for detailed analysis. Inhibitor assays revealed that ABA inhibitor (Fluridone) or H2O2 inhibitor (DMTU) was involved in the drought- or salt-induced transcription of GmDi19-5. The GUS activity driven by the GmDi19-5 promoter was induced by salt, PEG, ABA, and MV treatments and tended to be accumulated in the vascular bundles and young leaves. A subcellular localization assay showed that GmDi19-5 protein localized in the nucleus. Further investigation showed that GmDi19-5 protein was involved in the interaction with GmLEA3.1. Overexpression of GmDi19-5 increased sensitivity of transgenic Arabidopsis plants to salt, drought, oxidative, and ABA stresses and regulated expression of several ABA/stress-associated genes. This present investigation showed that GmDi19-5 functioned as a negative factor under abiotic stresses and was involved in ABA and SOS signaling pathway by altering transcription of stress-associated genes. PMID:25852726

  1. Mutations in ABO1/ELO2, a Subunit of Holo-Elongator, Increase Abscisic Acid Sensitivity and Drought Tolerance in Arabidopsis thaliana

    PubMed Central

    Chen, Zhizhong; Zhang, Hairong; Jablonowski, Daniel; Zhou, Xiaofeng; Ren, Xiaozhi; Hong, Xuhui; Schaffrath, Raffael; Zhu, Jian-Kang; Gong, Zhizhong

    2006-01-01

    The phytohormone abscisic acid (ABA) plays an important role in modulating plant growth, development, and stress responses. In a genetic screen for mutants with altered drought stress responses, we identified an ABA-overly sensitive mutant, the abo1 mutant, which showed a drought-resistant phenotype. The abo1 mutation enhances ABA-induced stomatal closing and increases ABA sensitivity in inhibiting seedling growth. abo1 mutants are more resistant to oxidative stress than the wild type and show reduced levels of transcripts of several stress- or ABA-responsive genes. Interestingly, the mutation also differentially modulates the development and growth of adjacent guard cells. Map-based cloning identified ABO1 as a new allele of ELO2, which encodes a homolog of Saccharomyces cerevisiae Iki3/Elp1/Tot1 and human IκB kinase-associated protein. Iki3/Elp1/Tot1 is the largest subunit of Elongator, a multifunctional complex with roles in transcription elongation, secretion, and tRNA modification. Ecotopic expression of plant ABO1/ELO2 in a tot1/elp1Δ yeast Elongator mutant complements resistance to zymocin, a yeast killer toxin complex, indicating that ABO1/ELO2 substitutes for the toxin-relevant function of yeast Elongator subunit Tot1/Elp1. Our results uncover crucial roles for ABO1/ELO2 in modulating ABA and drought responses in Arabidopsis thaliana. PMID:16943431

  2. An ABA-mimicking ligand that reduces water loss and promotes drought resistance in plants

    PubMed Central

    Cao, Minjie; Liu, Xue; Zhang, Yan; Xue, Xiaoqian; Zhou, X Edward; Melcher, Karsten; Gao, Pan; Wang, Fuxing; Zeng, Liang; Zhao, Yang; Zhao, Yang; Deng, Pan; Zhong, Dafang; Zhu, Jian-Kang; Xu, H Eric; Xu, Yong

    2013-01-01

    Abscisic acid (ABA) is the most important hormone for plants to resist drought and other abiotic stresses. ABA binds directly to the PYR/PYL family of ABA receptors, resulting in inhibition of type 2C phosphatases (PP2C) and activation of downstream ABA signaling. It is envisioned that intervention of ABA signaling by small molecules could help plants to overcome abiotic stresses such as drought, cold and soil salinity. However, chemical instability and rapid catabolism by plant enzymes limit the practical application of ABA itself. Here we report the identification of a small molecule ABA mimic (AM1) that acts as a potent activator of multiple members of the family of ABA receptors. In Arabidopsis, AM1 activates a gene network that is highly similar to that induced by ABA. Treatments with AM1 inhibit seed germination, prevent leaf water loss, and promote drought resistance. We solved the crystal structure of AM1 in complex with the PYL2 ABA receptor and the HAB1 PP2C, which revealed that AM1 mediates a gate-latch-lock interacting network, a structural feature that is conserved in the ABA-bound receptor/PP2C complex. Together, these results demonstrate that a single small molecule ABA mimic can activate multiple ABA receptors and protect plants from water loss and drought stress. Moreover, the AM1 complex crystal structure provides a structural basis for designing the next generation of ABA-mimicking small molecules. PMID:23835477

  3. A role for PacMYBA in ABA-regulated anthocyanin biosynthesis in red-colored sweet cherry cv. Hong Deng (Prunus avium L.).

    PubMed

    Shen, Xinjie; Zhao, Kai; Liu, Linlin; Zhang, Kaichun; Yuan, Huazhao; Liao, Xiong; Wang, Qi; Guo, Xinwei; Li, Fang; Li, Tianhong

    2014-05-01

    The MYB transcription factors and plant hormone ABA have been suggested to play a role in fruit anthocyanin biosynthesis, but supporting genetic evidence has been lacking in sweet cherry. The present study describes the first functional characterization of an R2R3-MYB transcription factor, PacMYBA, from red-colored sweet cherry cv. Hong Deng (Prunus avium L.). Transient promoter assays demonstrated that PacMYBA physically interacted with several anthocyanin-related basic helix-loop-helix (bHLH) transcription factors to activate the promoters of PacDFR, PacANS and PacUFGT, which are thought to be involved in anthocyanin biosynthesis. Furthermore, the immature seeds of transgenic Arabidopsis plants overexpressing PacMYBA exhibited ectopic pigmentation. Silencing of PacMYBA, using a Tobacco rattle virus (TRV)-induced gene silencing technique, resulted in sweet cherry fruit that lacked red pigment. ABA treatment significantly induced anthocyanin accumulation, while treatment with the ABA biosynthesis inhibitor nordihydroguaiaretic acid (NDGA) blocked anthocyanin production. PacMYBA expression peaked after 2 h of pre-incubation in ABA and was 15.2-fold higher than that of sweet cherries treated with NDGA. The colorless phenotype was also observed in the fruits silenced in PacNCED1, which encodes a key enzyme in the ABA biosynthesis pathway. The endogenous ABA content as well as the transcript levels of six structural genes and PacMYBA in PacNCED1-RNAi (RNA interference) fruit were significantly lower than in the TRV vector control fruit. These results suggest that PacMYBA plays an important role in ABA-regulated anthocyanin biosynthesis and ABA is a signal molecule that promotes red-colored sweet cherry fruit accumulating anthocyanin.

  4. Dithiocarbamate fungicides increase intracellular Zn(2+) levels by increasing influx of Zn(2+) in rat thymic lymphocytes.

    PubMed

    Kanemoto-Kataoka, Yumiko; Oyama, Tomohiro M; Ishibashi, Hitoshi; Oyama, Yasuo

    2015-07-25

    Dithiocarbamate fungicides are used as alternative antifouling agents to highly toxic organotin antifouling agents, such as tri-n-butyltin and triphenyltin. There are some concerns regarding their environmental and health risks. It has been shown that tri-n-butyltin increases intracellular Zn(2+) levels of mammalian lymphocytes. Therefore, we examined the effects of dithiocarbamate fungicides (Ziram, Thiram, and Zineb) on rat thymic lymphocytes using a flow-cytometric technique to elucidate how these fungicides affect intracellular Zn(2+) levels. We further determined whether the agents increase intracellular Zn(2+) and/or Ca(2+), because both Zn(2+) and Ca(2+) are intracellular signals in lymphocytes, and excessive increases in their intracellular concentrations can have adverse effects. Dithiocarbamate fungicides increased intracellular Zn(2+) levels, without affecting intracellular Ca(2+) levels. Ziram was the most potent compound, increasing intracellular Zn(2+) levels via Zn(2+) influx. Ziram (1μM) greatly decreased the cellular nonprotein thiol content, and Zn(2+) chelators attenuated the Ziram-induced decrease. Ziram increased the population of annexin V-positive cells in a Zn(2+)-dependent manner. Therefore, we propose that dithiocarbamate fungicides induce Zn(2+) influx, resulting in an excessive elevation of intracellular Zn(2+) levels, leading to the induction of apoptosis. This study gives a basic insight into the mechanisms of dithiocarbamate fungicide-induced adverse events.

  5. Structural basis for selective activation of ABA receptors

    SciTech Connect

    Peterson, Francis C.; Burgie, E. Sethe; Park, Sang-Youl; Jensen, Davin R.; Weiner, Joshua J.; Bingman, Craig A.; Chang, Chia-En A.; Cutler, Sean R.; Phillips, Jr., George N.; Volkman, Brian F.

    2010-11-01

    Changing environmental conditions and lessening fresh water supplies have sparked intense interest in understanding and manipulating abscisic acid (ABA) signaling, which controls adaptive responses to drought and other abiotic stressors. We recently discovered a selective ABA agonist, pyrabactin, and used it to discover its primary target PYR1, the founding member of the PYR/PYL family of soluble ABA receptors. To understand pyrabactin's selectivity, we have taken a combined structural, chemical and genetic approach. We show that subtle differences between receptor binding pockets control ligand orientation between productive and nonproductive modes. Nonproductive binding occurs without gate closure and prevents receptor activation. Observations in solution show that these orientations are in rapid equilibrium that can be shifted by mutations to control maximal agonist activity. Our results provide a robust framework for the design of new agonists and reveal a new mechanism for agonist selectivity.

  6. The Top 10 Reasons Children With Autism Deserve ABA

    PubMed Central

    Walsh, Mary Beth

    2011-01-01

    We who advocate for applied behavior analysis (ABA) for children with autism spectrum disorders often construct our arguments based on the scientific evidence. However, the audience that most needs to hear this argument, that is, the parents of children, especially very young children, diagnosed with autism, may not be convinced by the science alone. This essay attempts to make the case for the multiple benefits of ABA intervention through the use of humor and anecdotes couched in a “Top Ten List,” and illustrating most points with stories of an engaging child with autism (my son, Ben). PMID:22532906

  7. Expression analysis of abscisic acid (ABA) and metabolic signalling factors in developing endosperm and embryo of barley☆

    PubMed Central

    Chen, Zhiwei; Huang, Jianhua; Muttucumaru, Nira; Powers, Stephen J.; Halford, Nigel G.

    2013-01-01

    The expression of genes encoding components of ABA and metabolic signalling pathways in developing barley endosperm and embryo was investigated. The genes included HvRCAR35_47387 and HvRCAR35_2538 (encoding ABA receptors), HvABI1d (protein phosphatase 2C), HvSnRK2.4, HvSnRK2.6 and HvPKABA1 (SnRK2-type protein kinases) and HvABI5 (ABA response element binding protein; AREBP), as well as two genes encoding SnRK1-type protein kinases. Both SnRK1 and SnRK2 phosphorylate AREBPs, but SnRK2 is activated by ABA whereas SnRK1 may be broken down. Multiple cereal AREBPs with two conserved SnRK1/2 target sites and another class of BZIP transcription factors with SnRK1/2 binding sites, including HvBLZ1, were identified. Barley grain (cv. Triumph) was sampled at 15, 20, 25 and 30 days post-anthesis (dpa). HvRCAR35_47387, HvABI1d, HvSnRK2.4 and HvABI5 were expressed highly in the endosperm but at much lower levels in the embryo. Conversely, HvPKABA1 and HvRCAR35_2538 were expressed at higher levels in the embryo than the endosperm, while HvSnRK2.6 was expressed at similar levels in both. HvRCAR35_47387, HvABI1d, HvSnRK2.4 and HvABI5 all peaked in expression in the endosperm at 20 dpa. A model is proposed in which ABA brings about a transition from a SnRK1-dominated state in the endosperm during grain filling to a SnRK2-dominated state during maturation. PMID:24748715

  8. Expression analysis of abscisic acid (ABA) and metabolic signalling factors in developing endosperm and embryo of barley.

    PubMed

    Chen, Zhiwei; Huang, Jianhua; Muttucumaru, Nira; Powers, Stephen J; Halford, Nigel G

    2013-09-01

    The expression of genes encoding components of ABA and metabolic signalling pathways in developing barley endosperm and embryo was investigated. The genes included HvRCAR35_47387 and HvRCAR35_2538 (encoding ABA receptors), HvABI1d (protein phosphatase 2C), HvSnRK2.4, HvSnRK2.6 and HvPKABA1 (SnRK2-type protein kinases) and HvABI5 (ABA response element binding protein; AREBP), as well as two genes encoding SnRK1-type protein kinases. Both SnRK1 and SnRK2 phosphorylate AREBPs, but SnRK2 is activated by ABA whereas SnRK1 may be broken down. Multiple cereal AREBPs with two conserved SnRK1/2 target sites and another class of BZIP transcription factors with SnRK1/2 binding sites, including HvBLZ1, were identified. Barley grain (cv. Triumph) was sampled at 15, 20, 25 and 30 days post-anthesis (dpa). HvRCAR35_47387, HvABI1d, HvSnRK2.4 and HvABI5 were expressed highly in the endosperm but at much lower levels in the embryo. Conversely, HvPKABA1 and HvRCAR35_2538 were expressed at higher levels in the embryo than the endosperm, while HvSnRK2.6 was expressed at similar levels in both. HvRCAR35_47387, HvABI1d, HvSnRK2.4 and HvABI5 all peaked in expression in the endosperm at 20 dpa. A model is proposed in which ABA brings about a transition from a SnRK1-dominated state in the endosperm during grain filling to a SnRK2-dominated state during maturation.

  9. Playground Designs to Increase Physical Activity Levels during School Recess: A Systematic Review

    ERIC Educational Resources Information Center

    Escalante, Yolanda; García-Hermoso, Antonio; Backx, Karianne; Saavedra, Jose M.

    2014-01-01

    School recess provides a major opportunity to increase children's physical activity levels. Various studies have described strategies to increase levels of physical activity. The purpose of this systematic review is therefore to examine the interventions proposed as forms of increasing children's physical activity levels during recess. A…

  10. Investigating the role of ABA signaling in wheat drought tolerance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Allohexaploid wheat (Triticum aestivum L.) is one of the three major cereal crops supporting human nutrition. Because wheat is often grown under dryland conditions, it is subject to losses as a result of drought stress. This study examines the role of the plant hormone ABA is wheat responses to wate...

  11. ABA and Diverse Cultural and Linguistic Environments: A Welsh Perspective

    ERIC Educational Resources Information Center

    Jones, E. W.; Hoerger, M.; Hughes, J. C.; Williams, B. M.; Jones, B.; Moseley, Y.; Hughes, D. R.; Prys, D.

    2011-01-01

    Gwynedd Local Education Authority (LEA) in North West Wales, UK, is funding a small-scale autism-specific specialist education service using ABA methodology. The program is available through the medium of Welsh, English or bilingually, depending on the individual needs of the child (Jones and Hoerger in Eur J Behav Anal 10:249-253,…

  12. ABA, AAB and ABC Renewal in Taste Aversion Learning

    ERIC Educational Resources Information Center

    Bernal-Gamboa, Rodolfo; Juarez, Yectivani; Gonzalez-Martin, Gabriela; Carranza, Rodrigo; Sanchez-Carrasco, Livia; Nieto, Javier

    2012-01-01

    Context renewal is identified when the conditioned response (CR) elicited by an extinguished conditioned stimulus (CS) reappears as a result of changing the contextual cues during the test. Two experiments were designed for testing contextual renewal in a conditioned taste aversion preparation. Experiment 1 assessed ABA and AAB context renewal,…

  13. Adaptive Behaviour Assessment System: Indigenous Australian Adaptation Model (ABAS: IAAM)

    ERIC Educational Resources Information Center

    du Plessis, Santie

    2015-01-01

    The study objectives were to develop, trial and evaluate a cross-cultural adaptation of the Adaptive Behavior Assessment System-Second Edition Teacher Form (ABAS-II TF) ages 5-21 for use with Indigenous Australian students ages 5-14. This study introduced a multiphase mixed-method design with semi-structured and informal interviews, school…

  14. Dissociations among ABA, ABC, and AAB Recovery Effects

    ERIC Educational Resources Information Center

    Ungor, Metin; Lachnit, Harald

    2008-01-01

    In a human predictive learning experiment, the strengths of ABA, ABC, and AAB recovery effects after discrimination reversal learning were compared. Initially, a discrimination between two stimuli (X+, Y-) was trained in Context A. During Phase 2, participants received discrimination reversal training (X-, Y+) either in Context A (Group AAB) or in…

  15. Increased von Willebrand factor levels in patients with systemic lupus erythematosus reflect inflammation rather than increased propensity for platelet activation

    PubMed Central

    Raymond, Warren D; Eilertsen, Gro Østli

    2016-01-01

    Background von Willebrand factor (VWF) is involved in platelet plug formation and protein transport. Increased VWF levels in systemic lupus erythematous (SLE) are considered risk factors for vascular events. VWF protein levels, however, do not accurately reflect its platelet-aggregating function, which has not been examined in SLE. Methods Cross-sectional study with clinical and laboratory data obtained in patients with SLE (n=92) from a regional lupus registry. VWF function was determined by ristocetin-induced platelet aggregation (VWF ristocetin cofactor, VWF:RCo) and VWF levels by turbidimetric assay (VWF antigen, VWF:Ag). The platelet-aggregating activity per VWF unit was estimated by the VWF RCo/Ag ratio. Healthy controls served as comparators and associations were evaluated by non-parametric methods. Results VWF:Ag (142% vs 107%, p=0.001) and VWF:RCo levels (123% vs 78%, p<0.041) were increased in patients with SLE, but VWF RCo/Ag ratio was similar as in controls (0.83 vs 0.82, p=0.8). VWF:Ag levels were higher in patients experiencing serositis but unrelated to other manifestations, thrombotic disease, Systemic Lupus Erythematous Disease Activity Index 2000 or Systemic Lupus International Collaborative Clinics-Damage Index. VWF:Ag levels correlated significantly with VWF:RCo levels (Rs 0.8, p<0.001), erythrocyte sedimentation rate (ESR) (Rs 0.32, p<0.01), anti-dsDNA Ab (Rs 0.27, p<0.01), total IgG (Rs 0.33 p<0.01), fibrinogen (Rs 0.28, p<0.01) and ceruloplasmin (Rs 0.367, p<0.01) levels. VWF:RCo levels were not related to clinical findings but were correlated with ESR, anti-dsDNA and transferrin levels. No serological associations existed for VWF RCo/Ag ratio (all p>0.2). Conclusions In this SLE cohort, VWF:Ag behaved similarly to acute-phase reactants, but VWF:Ag increases were not matched by increases in functional activity per unit of VWF. Thus, more VWF did not increase the propensity for platelet aggregation in SLE. PMID:27651919

  16. Effects of high night temperature and abscisic acid (ABA) on rice (Oryza sativa L.) physiology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    High night temperature (HNT) is known to decrease rice yields. The impact of abscisic acid (ABA) on plants has been the subject of many studies. However, little or no work has been carried out on rice response to ABA under HNT-stress conditions. This study determined the effects of ABA on rice leaf ...

  17. ABA and Instruction of Students with Autism Spectrum Disorders: Introduction to the Special Series.

    ERIC Educational Resources Information Center

    Heflin, L. Juane; Alberto, Paul A.

    2001-01-01

    This introductory article to this special issue on the use of applied behavior analysis (ABA) with autism spectrum disorders (ASD) notes the 40-year history of ABA strategy development, verification, and generalization. It briefly introduces the following articles, which are intended to illustrate the range of ABA applications and the depth of…

  18. Coping as a Predictor of Burnout and General Health in Therapists Working in ABA Schools

    ERIC Educational Resources Information Center

    Griffith, G. M.; Barbakou, A.; Hastings, R. P.

    2014-01-01

    Background: Little is known about the work-related well-being of applied behaviour analysis (ABA) therapists who work in school-based contexts and deliver ABA interventions to children with autism. Methods: A questionnaire on work-related stress (burnout), general distress, perceived supervisor support and coping was completed by 45 ABA therapists…

  19. Abscisic acid promotes accumulation of toxin ODAP in relation to free spermine level in grass pea seedlings (Lathyrus sativus L.).

    PubMed

    Xiong, You-Cai; Xing, Geng-Mei; Li, Feng-Min; Wang, Shao-Ming; Fan, Xian-Wei; Li, Zhi-Xiao; Wang, Ya-Fu

    2006-01-01

    Interrelationship among abscisic acid (ABA) content, accumulation of free polyamines and biosynthesis of beta-N-oxalyl-l-alpha,beta-diaminopropionic acid (ODAP) was studied in grass pea (Lathyrus sativus L.) seedlings under drought stress induced by 10% polyethylene glycol (PEG6000). Increase of ABA content occurred prior to that of ODAP and polyamine contents, and was found significantly positive correlation between ABA content and ODAP content. Addition of exogenous ABA increased ODAP content in leaves. On the other hand, pretreatment with alpha-difluoromethylarginine (DFMA), a polyamine biosynthesis inhibitor, significantly suppressed the accumulation of free putrescine (Put), free spermidine (Spd) and free spermine (Spm), which in turn inhibited biosynthesis of ODAP in well-watered leaves. Meanwhile, addition of exogenous Put alleviated DFMA-induced inhibition on the biosynthesis of Put and Spd, but did not affect the biosynthesis of Spm and ODAP in well-watered leaves. Same result was also achieved in drought-stressed leaves. Increasing accumulation of ODAP was significantly correlated with increasing Spm content (R=0.7957**) but not with that of Spd and Put. Therefore, it can be argued that ABA stimulated the biosynthesis of ODAP simultaneously with increasing the level of free Spm under drought stress condition.

  20. Inactivation of PYR/PYL/RCAR ABA receptors by tyrosine nitration may enable rapid inhibition of ABA signaling by nitric oxide in plants.

    PubMed

    Castillo, Mari-Cruz; Lozano-Juste, Jorge; González-Guzmán, Miguel; Rodriguez, Lesia; Rodriguez, Pedro L; León, José

    2015-09-01

    Abscisic acid (ABA) is a phytohormone that inhibits growth and enhances adaptation to stress in plants. ABA perception and signaling rely on its binding to receptors of the pyrabactin resistance1/PYR1-like/regulatory components of ABA receptors (PYR/PYL/RCAR) family, the subsequent inhibition of clade A type 2C protein phosphatases (PP2Cs), and the phosphorylation of ion channels and transcription factors by protein kinases of the SnRK2 family. Nitric oxide (NO) may inhibit ABA signaling because NO-deficient plants are hypersensitive to ABA. Regulation by NO often involves posttranslational modification of proteins. Mass spectrometry analysis of ABA receptors expressed in plants and recombinant receptors modified in vitro revealed that the receptors were nitrated at tyrosine residues and S-nitrosylated at cysteine residues. In an in vitro ABA-induced, PP2C inhibition assay, tyrosine nitration reduced receptor activity, whereas S-nitrosylated receptors were fully capable of ABA-induced inhibition of the phosphatase. PYR/PYL/RCAR proteins with nitrated tyrosine, which is an irreversible covalent modification, were polyubiquitylated and underwent proteasome-mediated degradation. We propose that tyrosine nitration, which requires NO and superoxide anions, is a rapid mechanism by which NO limits ABA signaling under conditions in which NO and reactive oxygen species are both produced.

  1. Central injection of CDP-choline suppresses serum ghrelin levels while increasing serum leptin levels in rats.

    PubMed

    Kiyici, Sinem; Basaran, Nesrin Filiz; Cavun, Sinan; Savci, Vahide

    2015-10-05

    In this study we aimed to test central administration of CDP-choline on serum ghrelin, leptin, glucose and corticosterone levels in rats. Intracerebroventricular (i.c.v.) 0.5, 1.0 and 2.0 µmol CDP-choline and saline were administered to male Wistar-Albino rats. For the measurement of serum leptin and ghrelin levels, blood samples were obtained baseline and at 5, 15, 30, 60 and 120 min following i.c.v. CDP-choline injection. Equimolar doses of i.c.v. choline (1.0 µmol) and cytidine (1.0 µmol) were administered and measurements were repeated throughout the second round of the experiment. Atropine (10 µg) and mecamylamine (50 µg) were injected intracerebroventricularly prior to CDP-choline and measurements repeated in the third round of the experiment. After 1 µmol CDP-choline injection, serum ghrelin levels were suppressed significantly at 60 min (P=0.025), whereas serum leptin levels were increased at 60 and 120 min (P=0.012 and P=0.017 respectively). CDP-choline injections also induced a dose- and time-dependent increase in serum glucose and corticosterone levels. The effect of choline on serum leptin and ghrelin levels was similar with CDP-choline while no effect was seen with cytidine. Suppression of serum ghrelin levels was eliminated through mecamylamine pretreatment while a rise in leptin was prevented by both atropine and mecamylamine pretreatments. In conclusion; centrally injected CDP-choline suppressed serum ghrelin levels while increasing serum leptin levels. The observed effects following receptor antagonist treatment suggest that nicotinic receptors play a role in suppression of serum ghrelin levels,whereas nicotinic and muscarinic receptors both play a part in the increase of serum leptin levels.

  2. Bundle-sheath cell regulation of xylem-mesophyll water transport via aquaporins under drought stress: a target of xylem-borne ABA?

    PubMed

    Shatil-Cohen, Arava; Attia, Ziv; Moshelion, Menachem

    2011-07-01

    The hydraulic conductivity of the leaf vascular system (K(leaf) ) is dynamic and decreases rapidly under drought stress, possibly in response to the stress phytohormone ABA, which increases sharply in the xylem sap (ABA(xyl) ) during periods of drought. Vascular bundle-sheath cells (BSCs; a layer of parenchymatous cells tightly enwrapping the entire leaf vasculature) have been hypothesized to control K(leaf) via the specific activity of BSC aquaporins (AQPs). We examined this hypothesis and provide evidence for drought-induced ABA(xyl) diminishing BSC osmotic water permeability (P(f) ) via downregulated activity of their AQPs. ABA fed to the leaf via the xylem (petiole) both decreased K(leaf) and led to stomatal closure, replicating the effect of drought. In contrast, smearing ABA on the leaf blade, while also closing stomata, did not decrease K(leaf) within 2-3 h of application, demonstrating that K(leaf) does not depend entirely on stomatal closure. GFP-labeled BSCs showed decreased P(f) in response to 'drought' and ABA treatment, and a reversible decrease with HgCl(2) (an AQP blocker). These P(f) responses, absent in mesophyll cells, suggest stress-regulated AQP activity specific to BSCs, and imply a role for these cells in decreasing K(leaf) via a reduction in P(f) . Our results support the above hypothesis and highlight the BSCs as hitherto overlooked vasculature sensor compartments, extending throughout the leaf and functioning as 'stress-regulated valves' converting vasculature chemical signals (possibly ABA(xyl) ) into leaf hydraulic signals.

  3. Arabidopsis ABA-Activated Kinase MAPKKK18 is Regulated by Protein Phosphatase 2C ABI1 and the Ubiquitin-Proteasome Pathway.

    PubMed

    Mitula, Filip; Tajdel, Malgorzata; Cieśla, Agata; Kasprowicz-Maluśki, Anna; Kulik, Anna; Babula-Skowrońska, Danuta; Michalak, Michal; Dobrowolska, Grazyna; Sadowski, Jan; Ludwików, Agnieszka

    2015-12-01

    Phosphorylation and dephosphorylation events play an important role in the transmission of the ABA signal. Although SnRK2 [sucrose non-fermenting1-related kinase2] protein kinases and group A protein phosphatase type 2C (PP2C)-type phosphatases constitute the core ABA pathway, mitogen-activated protein kinase (MAPK) pathways are also involved in plant response to ABA. However, little is known about the interplay between MAPKs and PP2Cs or SnRK2 in the regulation of ABA pathways. In this study, an effort was made to elucidate the role of MAP kinase kinase kinase18 (MKKK18) in relation to ABA signaling and response. The MKKK18 knockout lines showed more vigorous root growth, decreased abaxial stomatal index and increased stomatal aperture under normal growth conditions, compared with the control wild-type Columbia line. In addition to transcriptional regulation of the MKKK18 promoter by ABA, we demonstrated using in vitro and in vivo kinase assays that the kinase activity of MKKK18 was regulated by ABA. Analysis of the cellular localization of MKKK18 showed that the active kinase was targeted specifically to the nucleus. Notably, we identified abscisic acid insensitive 1 (ABI1) PP2C as a MKKK18-interacting protein, and demonstrated that ABI1 inhibited its activity. Using a cell-free degradation assay, we also established that MKKK18 was unstable and was degraded by the proteasome pathway. The rate of MKKK18 degradation was delayed in the ABI1 knockout line. Overall, we provide evidence that ABI1 regulates the activity and promotes proteasomal degradation of MKKK18.

  4. Arabidopsis ABA-Activated Kinase MAPKKK18 is Regulated by Protein Phosphatase 2C ABI1 and the Ubiquitin–Proteasome Pathway

    PubMed Central

    Mitula, Filip; Tajdel, Malgorzata; Cieśla, Agata; Kasprowicz-Maluśki, Anna; Kulik, Anna; Babula-Skowrońska, Danuta; Michalak, Michal; Dobrowolska, Grazyna; Sadowski, Jan; Ludwików, Agnieszka

    2015-01-01

    Phosphorylation and dephosphorylation events play an important role in the transmission of the ABA signal. Although SnRK2 [sucrose non-fermenting1-related kinase2] protein kinases and group A protein phosphatase type 2C (PP2C)-type phosphatases constitute the core ABA pathway, mitogen-activated protein kinase (MAPK) pathways are also involved in plant response to ABA. However, little is known about the interplay between MAPKs and PP2Cs or SnRK2 in the regulation of ABA pathways. In this study, an effort was made to elucidate the role of MAP kinase kinase kinase18 (MKKK18) in relation to ABA signaling and response. The MKKK18 knockout lines showed more vigorous root growth, decreased abaxial stomatal index and increased stomatal aperture under normal growth conditions, compared with the control wild-type Columbia line. In addition to transcriptional regulation of the MKKK18 promoter by ABA, we demonstrated using in vitro and in vivo kinase assays that the kinase activity of MKKK18 was regulated by ABA. Analysis of the cellular localization of MKKK18 showed that the active kinase was targeted specifically to the nucleus. Notably, we identified abscisic acid insensitive 1 (ABI1) PP2C as a MKKK18-interacting protein, and demonstrated that ABI1 inhibited its activity. Using a cell-free degradation assay, we also established that MKKK18 was unstable and was degraded by the proteasome pathway. The rate of MKKK18 degradation was delayed in the ABI1 knockout line. Overall, we provide evidence that ABI1 regulates the activity and promotes proteasomal degradation of MKKK18. PMID:26443375

  5. Optical conductivity of ABA stacked graphene trilayer: mid-IR resonance due to band nesting

    NASA Astrophysics Data System (ADS)

    Rashidian, Zeinab; Bludov, Yuliy V.; Ribeiro, Ricardo M.; Peres, N. M. R.; Vasilevskiy, Mikhail I.

    2014-10-01

    The band structure and the optical conductivity of an ABA (Bernal-type) stacked graphene trilayer are calculated. It is shown that, under appropriate doping, a strong resonant peak develops in the optical conductivity, located at the frequency corresponding to approximately 1.4 times the interlayer hopping energy and caused by the ‘nesting’ of two nearly parabolic bands in the electronic spectrum. The intensity of this resonant absorption can be controlled by adjusting the gate voltage. The effect is robust with respect to increasing temperature.

  6. The aba mutant of Arabidopsis thaliana is impaired in epoxy-carotenoid biosynthesis

    SciTech Connect

    Rock, C.D.; Zeevaart, J.A.D. )

    1991-09-01

    The three mutant alleles of the ABA locus of Arabidopsis thaliana result in plants that are deficient in the plant growth regulator abscisic acid (ABA). The authors have used {sup 18}O{sub 2} to label ABA in water-stressed leaves of mutant and wild-type Arabidopsis. Analysis by selected ion monitoring and tandem mass spectrometry of ({sup 18}O)ABA and its catabolites, phaseic acid and ABA-glucose ester ({beta}-D-glucopyranosyl abscisate), indicates that the aba genotypes are impaired in ABA biosynthesis and have a small ABA precursor pool of compounds that contain oxygens on the rings, presumably oxygenated carotenoids (xanthophylls). Quantitation of the carotenoids form mutant and wild-type leaves establishes that the aba alleles cause a deficiency of the epoxy-carotenoids violaxanthin and neoxanthin and an accumulation of their biosynthetic precursor, zeaxanthin. These results provide evidence that ABA is synthesized by oxidative cleavage of epoxy-carotenoids (the indirect pathway). Furthermore the carotenoid mutant they describe undergoes normal greening. Thus the aba alleles provide an opportunity to study the physiological roles of epoxy-carotenoids in photosynthesis in a higher plants.

  7. Trophic assimilation efficiency markedly increases at higher trophic levels in four-level host-parasitoid food chain.

    PubMed

    Sanders, Dirk; Moser, Andrea; Newton, Jason; van Veen, F J Frank

    2016-03-16

    Trophic assimilation efficiency (conversion of resource biomass into consumer biomass) is thought to be a limiting factor for food chain length in natural communities. In host-parasitoid systems, which account for the majority of terrestrial consumer interactions, a high trophic assimilation efficiency may be expected at higher trophic levels because of the close match of resource composition of host tissue and the consumer's resource requirements, which would allow for longer food chains. We measured efficiency of biomass transfer along an aphid-primary-secondary-tertiary parasitoid food chain and used stable isotope analysis to confirm trophic levels. We show high efficiency in biomass transfer along the food chain. From the third to the fourth trophic level, the proportion of host biomass transferred was 45%, 65% and 73%, respectively, for three secondary parasitoid species. For two parasitoid species that can act at the fourth and fifth trophic levels, we show markedly increased trophic assimilation efficiencies at the higher trophic level, which increased from 45 to 63% and 73 to 93%, respectively. In common with other food chains, δ(15)N increased with trophic level, with trophic discrimination factors (Δ(15)N) 1.34 and 1.49‰ from primary parasitoids to endoparasitic and ectoparasitic secondary parasitoids, respectively, and 0.78‰ from secondary to tertiary parasitoids. Owing to the extraordinarily high efficiency of hyperparasitoids, cryptic higher trophic levels may exist in host-parasitoid communities, which could alter our understanding of the dynamics and drivers of community structure of these important systems.

  8. Type B Heterotrimeric G Protein γ-Subunit Regulates Auxin and ABA Signaling in Tomato.

    PubMed

    Subramaniam, Gayathery; Trusov, Yuri; Lopez-Encina, Carlos; Hayashi, Satomi; Batley, Jacqueline; Botella, José Ramón

    2016-02-01

    Heterotrimeric G proteins composed of α, β, and γ subunits are central signal transducers mediating the cellular response to multiple stimuli in most eukaryotes. Gγ subunits provide proper cellular localization and functional specificity to the heterotrimer complex. Plant Gγ subunits, divided into three structurally distinct types, are more diverse than their animal counterparts. Type B Gγ subunits, lacking a carboxyl-terminal isoprenylation motif, are found only in flowering plants. We present the functional characterization of type B Gγ subunit (SlGGB1) in tomato (Solanum lycopersicum). We show that SlGGB1 is the most abundant Gγ subunit in tomato and strongly interacts with the Gβ subunit. Importantly, the green fluorescent protein-SlGGB1 fusion protein as well as the carboxyl-terminal yellow fluorescent protein-SlGGB1/amino-terminal yellow fluorescent protein-Gβ heterodimer were localized in the plasma membrane, nucleus, and cytoplasm. RNA interference-mediated silencing of SlGGB1 resulted in smaller seeds, higher number of lateral roots, and pointy fruits. The silenced lines were hypersensitive to exogenous auxin, while levels of endogenous auxins were lower or similar to those of the wild type. SlGGB1-silenced plants also showed strong hyposensitivity to abscisic acid (ABA) during seed germination but not in other related assays. Transcriptome analysis of the transgenic seeds revealed abnormal expression of genes involved in ABA sensing, signaling, and response. We conclude that the type B Gγ subunit SlGGB1 mediates auxin and ABA signaling in tomato.

  9. ABA is required for the accumulation of APX1 and MBF1c during a combination of water deficit and heat stress

    PubMed Central

    Zandalinas, Sara I.; Balfagón, Damián; Arbona, Vicent; Gómez-Cadenas, Aurelio; Inupakutika, Madhuri A.; Mittler, Ron

    2016-01-01

    Abscisic acid (ABA) plays a key role in plant acclimation to abiotic stress. Although recent studies suggested that ABA could also be important for plant acclimation to a combination of abiotic stresses, its role in this response is currently unknown. Here we studied the response of mutants impaired in ABA signalling (abi1-1) and biosynthesis (aba1-1) to a combination of water deficit and heat stress. Both mutants displayed reduced growth, biomass, and survival when subjected to stress combination. Focusing on abi1-1, we found that although its stomata had an impaired response to water deficit, remaining significantly more open than wild type, its stomatal aperture was surprisingly reduced when subjected to the stress combination. Stomatal closure during stress combination in abi1-1 was accompanied by higher levels of H2O2 in leaves, suggesting that H2O2 might play a role in this response. In contrast to the almost wild-type stomatal closure phenotype of abi1-1 during stress combination, the accumulation of ascorbate peroxidase 1 and multiprotein bridging factor 1c proteins, required for acclimation to a combination of water deficit and heat stress, was significantly reduced in abi1-1. Our findings reveal a key function for ABA in regulating the accumulation of essential proteins during a combination of water deficit and heat stress. PMID:27497287

  10. ABA is required for the accumulation of APX1 and MBF1c during a combination of water deficit and heat stress.

    PubMed

    Zandalinas, Sara I; Balfagón, Damián; Arbona, Vicent; Gómez-Cadenas, Aurelio; Inupakutika, Madhuri A; Mittler, Ron

    2016-10-01

    Abscisic acid (ABA) plays a key role in plant acclimation to abiotic stress. Although recent studies suggested that ABA could also be important for plant acclimation to a combination of abiotic stresses, its role in this response is currently unknown. Here we studied the response of mutants impaired in ABA signalling (abi1-1) and biosynthesis (aba1-1) to a combination of water deficit and heat stress. Both mutants displayed reduced growth, biomass, and survival when subjected to stress combination. Focusing on abi1-1, we found that although its stomata had an impaired response to water deficit, remaining significantly more open than wild type, its stomatal aperture was surprisingly reduced when subjected to the stress combination. Stomatal closure during stress combination in abi1-1 was accompanied by higher levels of H2O2 in leaves, suggesting that H2O2 might play a role in this response. In contrast to the almost wild-type stomatal closure phenotype of abi1-1 during stress combination, the accumulation of ascorbate peroxidase 1 and multiprotein bridging factor 1c proteins, required for acclimation to a combination of water deficit and heat stress, was significantly reduced in abi1-1 Our findings reveal a key function for ABA in regulating the accumulation of essential proteins during a combination of water deficit and heat stress.

  11. Rheology and Relaxation Timescales of ABA Triblock Polymer Gels

    NASA Astrophysics Data System (ADS)

    Peters, Andrew; Lodge, Timothy

    When dissolved in a midblock selective solvent, ABA polymers form gels composed of aggregated end block micelles bridged by the midblocks. While much effort has been devoted to the study of the structure of these systems, the dynamics of these systems has received less attention. We examine the underlying mechanism of shear relaxation of ABA triblock polymer gels, especially as a function of chain length, composition, and concentration. Recent work using time-resolved small-angle neutron scattering of polystyrene (PS)-block-poly(ethylene-alt-propylene) (PEP) in squalane has elucidated many aspects of the dynamics of diblock chain exchange. By using rheology to study bulk relaxation phenomena of the triblock equivalent, PS-PEP-PS, we apply the knowledge gained from the chain exchange studies to bridge the gap between the molecular and macroscopic relaxation phenomena in PS-PEP-PS triblock gels.

  12. Glycine facilitates gamma-glutamylcysteinylethyl ester-mediated increase in liver glutathione level.

    PubMed

    Nishida, K; Ohta, Y; Ishiguro, I

    1997-08-27

    gamma-Glutamylcysteinylethyl ester (gamma-GCE) increases reduced glutathione (GSH) levels in GSH-depleted rat hepatocytes. Because glycine, a constituent of GSH, exists at 0.3 to 0.4 mM in rat plasma, we examined the influence of glycine added to the medium on the action of gamma-GCE to increase GSH levels in the rat hepatocytes. Glycine (0.2-0.8 mM) dose-dependently enhanced gamma-GCE-mediated increase in intracellular GSH levels with an increase in intracellular gamma-GCE levels. These results indicate that exogenous glycine facilitates gamma-GCE-mediated increase in intracellular GSH levels in rat hepatocytes possibly by enhancing the uptake of gamma-GCE into the cells.

  13. Algorithm for Increasing Traffic Capacity of Level-Crossing Using Scheduling Theory and Intelligent Embedded Devices

    NASA Astrophysics Data System (ADS)

    Alps, Ivars; Gorobetz, Mikhail; Levchenkov, Anatoly

    2011-01-01

    In this paper the authors present heuristics algorithm for level-crossing traffic capacity increasing. The genetic algorithm is proposed for this task solution. The control of motion speed and operation with level-crossing barriers are proposed to create control centre and installed embedded intelligent devices on railway vehicles. Algorithm is tested using computer. The results of experiments show big promises for rail transport schedule fulfilment and level-crossing traffic capacity increasing using proposed algorithm.

  14. Possible Increase in Serum FABP4 Level Despite Adiposity Reduction by Canagliflozin, an SGLT2 Inhibitor

    PubMed Central

    Furuhashi, Masato; Matsumoto, Megumi; Hiramitsu, Shinya; Omori, Akina; Tanaka, Marenao; Moniwa, Norihito; Yoshida, Hideaki; Ishii, Junnichi; Miura, Tetsuji

    2016-01-01

    Background Fatty acid-binding protein 4 (FABP4/A-FABP/aP2) is secreted from adipocytes in association with catecholamine-induced lipolysis, and elevated serum FABP4 level is associated with obesity, insulin resistance and atherosclerosis. Secreted FABP4 as a novel adipokine leads to insulin resistance via increased hepatic glucose production (HGP). Sodium-glucose cotransporter 2 (SGLT2) inhibitors decrease blood glucose level via increased urinary glucose excretion, though HGP is enhanced. Here we investigated whether canagliflozin, an SGLT2 inhibitor, modulates serum FABP4 level. Methods Canagliflozin (100 mg/day) was administered to type 2 diabetic patients (n = 39) for 12 weeks. Serum FABP4 level was measured before and after treatment. Results At baseline, serum FABP4 level was correlated with adiposity, renal dysfunction and noradrenaline level. Treatment with canagliflozin significantly decreased adiposity and levels of fasting glucose and HbA1c but increased average serum FABP4 level by 10.3% (18.0 ± 1.0 vs. 19.8 ± 1.2 ng/ml, P = 0.008), though elevation of FABP4 level after treatment was observed in 26 (66.7%) out of 39 patients. Change in FABP4 level was positively correlated with change in levels of fasting glucose (r = 0.329, P = 0.044), HbA1c (r = 0.329, P = 0.044) and noradrenaline (r = 0.329, P = 0.041) but was not significantly correlated with change in adiposity or other variables. Conclusions Canagliflozin paradoxically increases serum FABP4 level in some diabetic patients despite amelioration of glucose metabolism and adiposity reduction, possibly via induction of catecholamine-induced lipolysis in adipocytes. Increased FABP4 level by canagliflozin may undermine the improvement of glucose metabolism and might be a possible mechanism of increased HGP by inhibition of SGLT2. Trial Registration UMIN-CTR Clinical Trial UMIN000018151 PMID:27124282

  15. Increased UVA exposures and decreased cutaneous Vitamin D(3) levels may be responsible for the increasing incidence of melanoma.

    PubMed

    Godar, Dianne E; Landry, Robert J; Lucas, Anne D

    2009-04-01

    Cutaneous malignant melanoma (CMM) has been increasing at a steady exponential rate in fair-skinned, indoor workers since before 1940. A paradox exists between indoor and outdoor workers because indoor workers get three to nine times less solar UV (290-400 nm) exposure than outdoor workers get, yet only indoor workers have an increasing incidence of CMM. Thus, another "factor(s)" is/are involved that increases the CMM risk for indoor workers. We hypothesize that one factor involves indoor exposures to UVA (321-400 nm) passing through windows, which can cause mutations and can break down vitamin D(3) formed after outdoor UVB (290-320 nm) exposure, and the other factor involves low levels of cutaneous vitamin D(3). After vitamin D(3) forms, melanoma cells can convert it to the hormone, 1,25-dihydroxyvitamin D(3), or calcitriol, which causes growth inhibition and apoptotic cell death in vitro and in vivo. We measured the outdoor and indoor solar irradiances and found indoor solar UVA irradiances represent about 25% (or 5-10 W/m(2)) of the outdoor irradiances and are about 60 times greater than fluorescent light irradiances. We calculated the outdoor and indoor UV contributions toward different biological endpoints by weighting the emission spectra by the action spectra: erythema, squamous cell carcinoma, melanoma (fish), and previtamin D(3). Furthermore, we found production of previtamin D(3) only occurs outside where there is enough UVB. We agree that intense, intermittent outdoor UV overexposures and sunburns initiate CMM; we now propose that increased UVA exposures and inadequately maintained cutaneous levels of vitamin D(3) promotes CMM.

  16. The ABA signal transduction mechanism in commercial crops: learning from Arabidopsis.

    PubMed

    Ben-Ari, Giora

    2012-08-01

    The phytohormone abscisic acid (ABA) affects a wide range of stages of plant development as well as the plant's response to biotic and abiotic stresses. Manipulation of ABA signaling in commercial crops holds promising potential for improving crop yields. Several decades of research have been invested in attempts to identify the first components of the ABA signaling cascade. It was only in 2009, that two independent groups identified the PYR/PYL/RCAR protein family as the plant ABA receptor. This finding was followed by a surge of studies on ABA signal transduction, many of them using Arabidopsis as their model. The ABA signaling cascade was found to consist of a double-negative regulatory mechanism assembled from three protein families. These include the ABA receptors, the PP2C family of inhibitors, and the kinase family, SnRK2. It was found that ABA-bound PYR/RCARs inhibit PP2C activity, and that PP2Cs inactivate SnRK2s. Researchers today are examining how the elucidation of the ABA signaling cascade in Arabidopsis can be applied to improvements in commercial agriculture. In this article, we have attempted to review recent studies which address this issue. In it, we discuss various approaches useful in identifying the genetic and protein components involved. Finally, we suggest possible commercial applications of genetic manipulation of ABA signaling to improve crop yields.

  17. Molecular basis of the core regulatory network in ABA responses: sensing, signaling and transport.

    PubMed

    Umezawa, Taishi; Nakashima, Kazuo; Miyakawa, Takuya; Kuromori, Takashi; Tanokura, Masaru; Shinozaki, Kazuo; Yamaguchi-Shinozaki, Kazuko

    2010-11-01

    ABA is a major phytohormone that regulates a broad range of plant traits and is especially important for adaptation to environmental conditions. Our understanding of the molecular basis of ABA responses in plants improved dramatically in 2009 and 2010, banner years for ABA research. There are three major components; PYR/PYL/ RCAR (an ABA receptor), type 2C protein phosphatase (PP2C; a negative regulator) and SNF1-related protein kinase 2 (SnRK2; a positive regulator), and they offer a double negative regulatory system, [PYR/PYL/RCAR-| PP2C-| SnRK2]. In the absence of ABA, PP2C inactivates SnRK2 by direct dephosphorylation. In response to environmental or developmental cues, ABA promotes the interaction of PYR/PYL/RCAR and PP2C, resulting in PP2C inhibition and SnRK2 activation. This signaling complex can work in both the nucleus and cytosol, as it has been shown that SnRK2 phosphorylates basic-domain leucine zipper (bZIP) transcription factors or membrane proteins. Several structural analyses of PYR/PYL/RCAR have provided the mechanistic basis for this 'core signaling' model, by elucidating the mechanism of ABA binding of receptors, or the 'gate-latch-lock' mechanism of interaction with PP2C in inhibiting activity. On the other hand, intercellular ABA transport had remained a major issue, as had intracellular ABA signaling. Recently, two plasma membrane-type ABC transporters were identified and shed light on the influx/efflux system of ABA, resolving how ABA is transported from cell to cell in plants. Our knowledge of ABA responses in plants has been greatly expanded from intracellular signaling to intercellular transport of ABA.

  18. ABA crosstalk with ethylene and nitric oxide in seed dormancy and germination

    PubMed Central

    Arc, Erwann; Sechet, Julien; Corbineau, Françoise; Rajjou, Loïc; Marion-Poll, Annie

    2013-01-01

    Dormancy is an adaptive trait that enables seed germination to coincide with favorable environmental conditions. It has been clearly demonstrated that dormancy is induced by abscisic acid (ABA) during seed development on the mother plant. After seed dispersal, germination is preceded by a decline in ABA in imbibed seeds, which results from ABA catabolism through 8′-hydroxylation. The hormonal balance between ABA and gibberellins (GAs) has been shown to act as an integrator of environmental cues to maintain dormancy or activate germination. The interplay of ABA with other endogenous signals is however less documented. In numerous species, ethylene counteracts ABA signaling pathways and induces germination. In Brassicaceae seeds, ethylene prevents the inhibitory effects of ABA on endosperm cap weakening, thereby facilitating endosperm rupture and radicle emergence. Moreover, enhanced seed dormancy in Arabidopsis ethylene-insensitive mutants results from greater ABA sensitivity. Conversely, ABA limits ethylene action by down-regulating its biosynthesis. Nitric oxide (NO) has been proposed as a common actor in the ABA and ethylene crosstalk in seed. Indeed, convergent evidence indicates that NO is produced rapidly after seed imbibition and promotes germination by inducing the expression of the ABA 8′-hydroxylase gene, CYP707A2, and stimulating ethylene production. The role of NO and other nitrogen-containing compounds, such as nitrate, in seed dormancy breakage and germination stimulation has been reported in several species. This review will describe our current knowledge of ABA crosstalk with ethylene and NO, both volatile compounds that have been shown to counteract ABA action in seeds and to improve dormancy release and germination. PMID:23531630

  19. ABA crosstalk with ethylene and nitric oxide in seed dormancy and germination.

    PubMed

    Arc, Erwann; Sechet, Julien; Corbineau, Françoise; Rajjou, Loïc; Marion-Poll, Annie

    2013-01-01

    Dormancy is an adaptive trait that enables seed germination to coincide with favorable environmental conditions. It has been clearly demonstrated that dormancy is induced by abscisic acid (ABA) during seed development on the mother plant. After seed dispersal, germination is preceded by a decline in ABA in imbibed seeds, which results from ABA catabolism through 8'-hydroxylation. The hormonal balance between ABA and gibberellins (GAs) has been shown to act as an integrator of environmental cues to maintain dormancy or activate germination. The interplay of ABA with other endogenous signals is however less documented. In numerous species, ethylene counteracts ABA signaling pathways and induces germination. In Brassicaceae seeds, ethylene prevents the inhibitory effects of ABA on endosperm cap weakening, thereby facilitating endosperm rupture and radicle emergence. Moreover, enhanced seed dormancy in Arabidopsis ethylene-insensitive mutants results from greater ABA sensitivity. Conversely, ABA limits ethylene action by down-regulating its biosynthesis. Nitric oxide (NO) has been proposed as a common actor in the ABA and ethylene crosstalk in seed. Indeed, convergent evidence indicates that NO is produced rapidly after seed imbibition and promotes germination by inducing the expression of the ABA 8'-hydroxylase gene, CYP707A2, and stimulating ethylene production. The role of NO and other nitrogen-containing compounds, such as nitrate, in seed dormancy breakage and germination stimulation has been reported in several species. This review will describe our current knowledge of ABA crosstalk with ethylene and NO, both volatile compounds that have been shown to counteract ABA action in seeds and to improve dormancy release and germination.

  20. Trophic assimilation efficiency markedly increases at higher trophic levels in four-level host–parasitoid food chain

    PubMed Central

    Moser, Andrea; van Veen, F. J. Frank

    2016-01-01

    Trophic assimilation efficiency (conversion of resource biomass into consumer biomass) is thought to be a limiting factor for food chain length in natural communities. In host–parasitoid systems, which account for the majority of terrestrial consumer interactions, a high trophic assimilation efficiency may be expected at higher trophic levels because of the close match of resource composition of host tissue and the consumer's resource requirements, which would allow for longer food chains. We measured efficiency of biomass transfer along an aphid-primary–secondary–tertiary parasitoid food chain and used stable isotope analysis to confirm trophic levels. We show high efficiency in biomass transfer along the food chain. From the third to the fourth trophic level, the proportion of host biomass transferred was 45%, 65% and 73%, respectively, for three secondary parasitoid species. For two parasitoid species that can act at the fourth and fifth trophic levels, we show markedly increased trophic assimilation efficiencies at the higher trophic level, which increased from 45 to 63% and 73 to 93%, respectively. In common with other food chains, δ15N increased with trophic level, with trophic discrimination factors (Δ15N) 1.34 and 1.49‰ from primary parasitoids to endoparasitic and ectoparasitic secondary parasitoids, respectively, and 0.78‰ from secondary to tertiary parasitoids. Owing to the extraordinarily high efficiency of hyperparasitoids, cryptic higher trophic levels may exist in host–parasitoid communities, which could alter our understanding of the dynamics and drivers of community structure of these important systems. PMID:26962141

  1. Strategies for Mitigating the Reduction in Economic Value of Variable Generation with Increasing Penetration Levels

    SciTech Connect

    Mills, Andrew; Wiser, Ryan

    2014-03-03

    In this report, we evaluate individual options that have the potential to stem the decline in the marginal value of variable generation (VG) with increasing penetration levels. We focus only on the effectiveness of mitigation measures for wind and PV.

  2. A Ketogenic Diet Increases Brown Adipose Tissue Mitochondrial Proteins and UCP1 Levels in Mice

    PubMed Central

    Srivastava, Shireesh; Baxa, Ulrich; Niu, Gang; Chen, Xiaoyuan; Veech, Richard L.

    2013-01-01

    We evaluated the effects of feeding a ketogenic diet (KD) for a month on general physiology with emphasis on brown adipose tissue (BAT) in mice. KD did not reduce the caloric intake, or weight or lipid content of BAT. Relative epididymal fat pads were 40% greater in the mice fed the KD (P = 0.06) while leptin was lower (P < 0.05). Blood glucose levels were 30% lower while D-β-hydroxybutyrate levels were about 3.5-fold higher in the KD group. Plasma insulin and leptin levels in the KD group were about half of that of the mice fed NIH-31 pellets (chow group). Median mitochondrial size in the inter-scapular BAT (IBAT) of the KD group was about 60% greater, whereas the median lipid droplet size was about half of that in the chow group. Mitochondrial oxidative phosphorylation proteins were increased (1.5–3-fold) and the uncoupling protein 1 levels were increased by threefold in mice fed the KD. The levels of PPARγ, PGC-1α, and Sirt1 in KD group were 1.5–3-fold while level of Sirt3 was about half of that in the chow-fed group. IBAT cyclic AMP levels were 60% higher in the KD group and cAMP response element binding protein was 2.5-fold higher, suggesting increased sympathetic system activity. These results demonstrate that a KD can also increase BAT mitochondrial size and protein levels. PMID:23233333

  3. Cafeteria diet increases prostaglandin E2 levels in rat prostate, kidney and testis.

    PubMed

    Brunetti, L; Leone, S; Chiavaroli, A; Orlando, G; Recinella, L; Ferrante, C; Di Nisio, C; Verratti, V; Vacca, M

    2010-01-01

    Nutrient composition, particularly the omega-6/omega-3 polyunsaturated fatty acids ratio, may differently affect inflammatory mediators production in tissues, which could be causally related to increased cancer incidence in obesity. We evaluated prostaglandin E(2) levels in male Wistar rat prostate, kidney and testicle tissues after 15 days of either a high fat, cafeteria-style diet (5.50 Kcal/g, 30 percent calories from fat, omega-6/omega-3 ratio 2.33) or a standard laboratory chow diet (3.35 Kcal/g, 3 percent calories from fat, omega-6/omega-3 ratio 0.56). In the cafeteria diet compared to standard laboratory diet rats, we found both an increase in weight gain and increased prostaglandin E(2) (PGE(2)) levels in prostate, kidney and testicle tissues. The increased levels of PGE(2) induced by the cafeteria diet could drive an inflammatory process leading to increased incidence of prostate, kidney and testicular cancer in overweight patients.

  4. Increasing levels of assistance in refinement of knowledge-based retrieval systems

    NASA Technical Reports Server (NTRS)

    Baudin, Catherine; Kedar, Smadar; Pell, Barney

    1994-01-01

    The task of incrementally acquiring and refining the knowledge and algorithms of a knowledge-based system in order to improve its performance over time is discussed. In particular, the design of DE-KART, a tool whose goal is to provide increasing levels of assistance in acquiring and refining indexing and retrieval knowledge for a knowledge-based retrieval system, is presented. DE-KART starts with knowledge that was entered manually, and increases its level of assistance in acquiring and refining that knowledge, both in terms of the increased level of automation in interacting with users, and in terms of the increased generality of the knowledge. DE-KART is at the intersection of machine learning and knowledge acquisition: it is a first step towards a system which moves along a continuum from interactive knowledge acquisition to increasingly automated machine learning as it acquires more knowledge and experience.

  5. B Lymphocyte Stimulator Levels in Systemic Lupus Erythematosus: Higher Circulating Levels in African American Patients and Increased Production after Influenza Vaccination in Patients with Low Baseline Levels

    PubMed Central

    Ritterhouse, Lauren L.; Crowe, Sherry R.; Niewold, Timothy B.; Merrill, Joan T.; Roberts, Virginia C.; Dedeke, Amy B.; Neas, Barbara R.; Thompson, Linda F.; Guthridge, Joel M.; James, Judith A.

    2011-01-01

    Objective Examine the relationship between circulating B lymphocyte stimulator (BLyS) levels and humoral responses to influenza vaccination in systemic lupus erythematosus (SLE) patients, as well as the effect of vaccination on BLyS levels. Clinical and serologic features of SLE that are associated with elevated BLyS levels will also be investigated. Methods Clinical history, disease activity measurements and blood specimens were collected from sixty SLE patients at baseline and after influenza vaccination. Sera were tested for BLyS levels, lupus-associated autoantibodies, serum IFN-α activity, 25-hydroxyvitamin D, and humoral responses to influenza vaccination. Results Thirty percent of SLE patients had elevated BLyS levels, with African American patients having higher BLyS levels than European American patients (p=0.006). Baseline BLyS levels in patients were not correlated with humoral responses to influenza vaccination (p=0.863), and BLyS levels increased post-vaccination only in the subset of patients in the lowest quartile of BLyS levels (p=0.0003). Elevated BLyS levels were associated with increased disease activity as measured by SLEDAI, PGA, and SLAM in European Americans (p=0.035, p=0.016, p=0.018, respectively), but not in African Americans. Elevated BLyS levels were also associated with anti-nRNP (p=0.0003) and decreased 25(OH)D (p=0.018). Serum IFN-α activity was a significant predictor of elevated BLyS in a multivariate analysis (p=0.002). Conclusion African American SLE patients have higher BLyS levels regardless of disease activity. Humoral response to influenza vaccination is not correlated with baseline BLyS levels in SLE patients and only those patients with low baseline BLyS levels demonstrate an increased BLyS response after vaccination. PMID:22127709

  6. Acute aerobic exercise increases brain-derived neurotrophic factor levels in elderly with Alzheimer's disease.

    PubMed

    Coelho, Flávia Gomes de Melo; Vital, Thays Martins; Stein, Angelica Miki; Arantes, Franciel José; Rueda, André Veloso; Camarini, Rosana; Teodorov, Elizabeth; Santos-Galduróz, Ruth Ferreira

    2014-01-01

    Studies indicate the involvement of brain-derived neurotrophic factor (BDNF) in the pathogenesis of Alzheimer's disease (AD). Decreased BDNF levels may constitute a lack of trophic support and contribute to cognitive impairment in AD. The benefits of acute and chronic physical exercise on BDNF levels are well-documented in humans, however, exercise effects on BDNF levels have not been analyzed in older adults with AD. The aim of this study was to investigate the effects of acute aerobic exercise on BDNF levels in older adults with AD and to verify associations among BDNF levels, aerobic fitness, and level of physical activity. Using a controlled design, twenty-one patients with AD (76.3 ± 6.2 years) and eighteen healthy older adults (74.6 ± 4.7 years) completed an acute aerobic exercise. The outcomes included measures of BDNF plasma levels, aerobic fitness (treadmill grade, time to exhaustion, VO2, and maximal lactate) and level of physical activity (Baecke Questionnaire Modified for the Elderly). The independent t-test shows differences between groups with respect to the BDNF plasma levels at baseline (p = 0.04; t = 4.53; df = 37). In two-way ANOVA, a significant effect of time was found (p = 0.001; F = 13.63; df = 37), the aerobic exercise significantly increased BDNF plasma levels in AD patients and healthy controls. A significant correlation (p = 0.04; r = 0.33) was found between BDNF levels and the level of physical activity. The results of our study suggest that aerobic exercise increases BDNF plasma levels in patients with AD and healthy controls. In addition to that, BDNF levels had association with level of physical activity.

  7. Molecular Mimicry Regulates ABA Signaling by SnRK2 Kinases and PP2C Phosphatases

    SciTech Connect

    Soon, Fen-Fen; Ng, Ley-Moy; Zhou, X. Edward; West, Graham M.; Kovach, Amanda; Tan, M.H. Eileen; Suino-Powell, Kelly M.; He, Yuanzheng; Xu, Yong; Chalmers, Michael J.; Brunzelle, Joseph S.; Zhang, Huiming; Yang, Huaiyu; Jiang, Hualiang; Li, Jun; Yong, Eu-Leong; Cutler, Sean; Zhu, Jian-Kang; Griffin, Patrick R.; Melcher, Karsten; Xu, H. Eric

    2014-10-02

    Abscisic acid (ABA) is an essential hormone for plants to survive environmental stresses. At the center of the ABA signaling network is a subfamily of type 2C protein phosphatases (PP2Cs), which form exclusive interactions with ABA receptors and subfamily 2 Snfl-related kinase (SnRK2s). Here, we report a SnRK2-PP2C complex structure, which reveals marked similarity in PP2C recognition by SnRK2 and ABA receptors. In the complex, the kinase activation loop docks into the active site of PP2C, while the conserved ABA-sensing tryptophan of PP2C inserts into the kinase catalytic cleft, thus mimicking receptor-PP2C interactions. These structural results provide a simple mechanism that directly couples ABA binding to SnRK2 kinase activation and highlight a new paradigm of kinase-phosphatase regulation through mutual packing of their catalytic sites.

  8. Molecular Mimicry Regulates ABA Signaling by SnRK2 Kinases and PP2C Phosphatases

    PubMed Central

    Soon, Fen-Fen; Ng, Ley-Moy; Zhou, X. Edward; West, Graham M.; Kovach, Amanda; Tan, M. H. Eileen; Suino-Powell, Kelly M.; He, Yuanzheng; Xu, Yong; Chalmers, Michael J.; Brunzelle, Joseph S.; Zhang, Huiming; Yang, Huaiyu; Jiang, Hualiang; Li, Jun; Yong, Eu-Leong; Cutler, Sean; Zhu, Jian-Kang; Griffin, Patrick R.; Melcher, Karsten; Xu, H. Eric

    2013-01-01

    Abscisic acid (ABA) is an essential hormone for plants to survive environmental stresses. At the center of the ABA signaling network is a subfamily of type 2C protein phosphatases (PP2Cs), which form exclusive interactions with ABA receptors and subfamily 2 Snfl-related kinase (SnRK2s). Here, we report a SnRK2-PP2C complex structure, which reveals marked similarity in PP2C recognition by SnRK2 and ABA receptors. In the complex, the kinase activation loop docks into the active site of PP2C, while the conserved ABA-sensing tryptophan of PP2C inserts into the kinase catalytic cleft, thus mimicking receptor-PP2C interactions. These structural results provide a simple mechanism that directly couples ABA binding to SnRK2 kinase activation and highlight a new paradigm of kinase-phosphatase regulation through mutual packing of their catalytic sites. PMID:22116026

  9. Molecular mimicry regulates ABA signaling by SnRK2 kinases and PP2C phosphatases.

    PubMed

    Soon, Fen-Fen; Ng, Ley-Moy; Zhou, X Edward; West, Graham M; Kovach, Amanda; Tan, M H Eileen; Suino-Powell, Kelly M; He, Yuanzheng; Xu, Yong; Chalmers, Michael J; Brunzelle, Joseph S; Zhang, Huiming; Yang, Huaiyu; Jiang, Hualiang; Li, Jun; Yong, Eu-Leong; Cutler, Sean; Zhu, Jian-Kang; Griffin, Patrick R; Melcher, Karsten; Xu, H Eric

    2012-01-06

    Abscisic acid (ABA) is an essential hormone for plants to survive environmental stresses. At the center of the ABA signaling network is a subfamily of type 2C protein phosphatases (PP2Cs), which form exclusive interactions with ABA receptors and subfamily 2 Snfl-related kinase (SnRK2s). Here, we report a SnRK2-PP2C complex structure, which reveals marked similarity in PP2C recognition by SnRK2 and ABA receptors. In the complex, the kinase activation loop docks into the active site of PP2C, while the conserved ABA-sensing tryptophan of PP2C inserts into the kinase catalytic cleft, thus mimicking receptor-PP2C interactions. These structural results provide a simple mechanism that directly couples ABA binding to SnRK2 kinase activation and highlight a new paradigm of kinase-phosphatase regulation through mutual packing of their catalytic sites.

  10. A Putative PP2C-Encoding Gene Negatively Regulates ABA Signaling in Populus euphratica.

    PubMed

    Chen, Jinhuan; Zhang, Dongzhi; Zhang, Chong; Xia, Xinli; Yin, Weilun; Tian, Qianqian

    2015-01-01

    A PP2C homolog gene was cloned from the drought-treated cDNA library of Populus euphratica. Multiple sequence alignment analysis suggested that the gene is a potential ortholog of HAB1. The expression of this HAB1 ortholog (PeHAB1) was markedly induced by drought and moderately induced by ABA. To characterize its function in ABA signaling, we generated transgenic Arabidopsis thaliana plants overexpressing this gene. Transgenic lines exhibited reduced responses to exogenous ABA and reduced tolerance to drought compared to wide-type lines. Yeast two-hybrid analyses indicated that PeHAB1 could interact with the ABA receptor PYL4 in an ABA-independent manner. Taken together; these results indicated that PeHAB1 is a new negative regulator of ABA responses in poplar.

  11. RAFT synthesis of ABA triblock copolymers as ionic liquid-containing electroactive membranes.

    PubMed

    Wu, Tianyu; Wang, Dong; Zhang, Mingqiang; Heflin, James R; Moore, Robert B; Long, Timothy E

    2012-12-01

    2-(Dimethylamino)ethyl acrylate (DMAEA) imparts versatile functionality to poly[Sty-b-(nBA-co-DMAEA)-b-Sty] ABA triblock copolymers. A controlled synthetic strategy minimized chain transfer reactions and enabled the preparation of high-molecular-weight ABA triblock copolymers with relatively narrow PDIs between 1.39 and 1.44 using reversible addition-fragmentation chain transfer (RAFT) polymerization. The presence of tertiary amine functionality and their zwitterionic derivatives in the central blocks of the triblock copolymers afforded tunable polarity toward ionic liquids. Gravimetric measurements determined the swelling capacity of the triblock copolymers for ionic liquids (IL) 1-ethyl-3-methylimidazolium trifluoromethanesulfonate (EMIm TfO) and 1-ethyl-3-methylimidazolium ethylsulfate (EMIm ES). A correlation of differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and small-angle X-ray scattering (SAXS) results revealed the impact of ionic liquid incorporation on the thermal transitions, thermomechanical properties, and morphologies of the triblock copolymers. IL-containing membranes of DMAEA-derived triblock copolymers and EMIm TfO exhibited desirable rubbery plateau moduli of ~100 MPa and electromechanical actuation to a 4 V electrical stimulus. Maintaining the mechanical ductility of polymer matrices while increasing their ion-conductivity is paramount for future electroactive devices.

  12. Increase in thyroid stimulating hormone levels in patients with gout treated with inhibitors of xanthine oxidoreductase.

    PubMed

    Perez-Ruiz, Fernando; Chinchilla, Sandra Pamela; Atxotegi, Joana; Urionagüena, Irati; Herrero-Beites, Ana Maria; Aniel-Quiroga, Maria Angeles

    2015-11-01

    Increase in thyroid stimulating hormone (TSH) levels over the upper normal limit has been reported in a small percentage of patients treated with febuxostat in clinical trials, but a mechanistic explanation is not yet available. In an observational parallel longitudinal cohort study, we evaluated changes in TSH levels in patients with gout at baseline and during urate-lowering treatment with febuxostat. Patients to be started on allopurinol who had a measurement of TSH in the 6-month period prior to baseline evaluation were used for comparison. TSH levels and change in TSH levels at 12-month follow-up were compared between groups. Patients with abnormal TSH levels or previous thyroid disease or on amiodarone were not included for analysis. Eighty-eight patients treated with febuxostat and 87 with allopurinol were available for comparisons. Patients to be treated with febuxostat had higher urate levels and TSH levels, more severe gout, and poorer renal function, but were similar regarding other characteristics. A similar rise in TSH levels was observed in both groups (0.4 and 0.5 µUI/mL for febuxostat and allopurinol, respectively); at 12-mo, 7/88 (7.9 %) of patients on febuxostat and 4/87 (3.4 %) of patients on allopurinol showed TSH levels over 0.5 µUI/mL. Doses prescribed (corrected for estimated glomerular filtration rate in the case if patients on allopurinol) and baseline TSH levels were determinants of TSH levels at 12-month follow-up. No impact on free T4 (fT4) levels was observed. Febuxostat, but also allopurinol, increased TSH levels in a dose-dependent way, thus suggesting rather a class effect than a drug effect, but with no apparent impact on either clinical or fT4 levels.

  13. Arabidopsis HY1-Modulated Stomatal Movement: An Integrative Hub Is Functionally Associated with ABI4 in Dehydration-Induced ABA Responsiveness1

    PubMed Central

    Xie, Yanjie; Mao, Yu; Duan, Xingliang; Zhou, Heng; Lai, Diwen; Zhang, Yihua; Shen, Wenbiao

    2016-01-01

    Heme oxygenase (HO; EC 1.14.99.3) has recently been proposed as a novel component in mediating wide ranges of the plant adaptive signaling processes. However, the physiological significance and molecular basis underlying Arabidopsis (Arabidopsis thaliana) HO1 (HY1) functioning in drought tolerance remained unclear. Here, we report that mutation of HY1 promoted, but overexpression of this gene impaired, Arabidopsis drought tolerance. This was attributed to the abscisic acid (ABA)-hypersensitive or -hyposensitive phenotypes, with the regulation of stomatal closure in particular. However, comparative transcriptomic profile analysis showed that the induction of numerous ABA/stress-dependent genes in dehydrated wild-type plants was differentially impaired in the hy1 mutant. In agreement, ABA-induced ABSCISIC ACID-INSENSITIVE4 (ABI4) transcript accumulation was strengthened in the hy1 mutant. Genetic analysis further identified that the hy1-associated ABA hypersensitivity and drought tolerance were arrested in the abi4 background. Moreover, the promotion of ABA-triggered up-regulation of RbohD abundance and reactive oxygen species (ROS) levels in the hy1 mutant was almost fully blocked by the mutation of ABI4, suggesting that the HY1-ABI4 signaling in the wild type involved in stomatal closure was dependent on the RbohD-derived ROS production. However, hy1-promoted stomatal closure was not affected by a nitric oxide scavenger. Correspondingly, ABA-insensitive behaviors in rbohD stomata were not affected by either the mutation of HY1 or its ectopic expression in the rbohD background, both of which responded significantly to exogenous ROS. These data indicate that HY1 functioned negatively and acted upstream of ABI4 in drought signaling, which was casually dependent on the RbohD-derived ROS in the regulation of stomatal closure. PMID:26704641

  14. Liming can decrease legume crop yield and leaf gas exchange by enhancing root to shoot ABA signalling.

    PubMed

    Rothwell, Shane A; Elphinstone, E David; Dodd, Ian C

    2015-04-01

    To meet future requirements for food production, sustainable intensive agricultural systems need to optimize nutrient availability to maximize yield, traditionally achieved by maintaining soil pH within an optimal range (6-6.5) by applying lime (calcium carbonate). However, a field trial that applied recommended liming rates to a sandy loam soil (increasing soil pH from 5.5 to 6.2) decreased pod yield of field bean (Vicia faba L. cv. Fuego) by ~30%. Subsequent pot trials, with liming that raised soil pH to 6.3-6.7, reduced stomatal conductance (g(s)) by 63, 26, and 59% in V. faba, bean (Phaseolus vulgaris), and pea (Pisum sativum), respectively. Furthermore, liming reduced shoot dry biomass by 16-24% in these species. Ionomic analysis of root xylem sap and leaf tissue revealed a decrease in phosphorus concentration that was correlated with decreased g(s): both reductions were partially reversed by adding superphosphate fertilizer. Further analysis of pea suggests that leaf gas exchange was reduced by a systemic increase (roots, xylem sap, and leaves) in the phytohormone abscisic acid (ABA) in response to lime-induced suboptimal plant phosphorus concentrations. Supplying synthetic ABA via the transpiration stream to detached pea leaves, at the same xylem sap concentrations induced by liming, decreased transpiration. Furthermore, the g(s) of the ABA-deficient mutant pea wilty was unresponsive to liming, apparently confirming that ABA mediates some responses to low phosphorus availability caused by liming. This research provides a detailed mechanistic understanding of the physiological processes by which lime application can limit crop yields, and questions the suitability of current liming recommendations.

  15. Liming can decrease legume crop yield and leaf gas exchange by enhancing root to shoot ABA signalling

    PubMed Central

    Rothwell, Shane A.; Elphinstone, E. David; Dodd, Ian C.

    2015-01-01

    To meet future requirements for food production, sustainable intensive agricultural systems need to optimize nutrient availability to maximize yield, traditionally achieved by maintaining soil pH within an optimal range (6–6.5) by applying lime (calcium carbonate). However, a field trial that applied recommended liming rates to a sandy loam soil (increasing soil pH from 5.5 to 6.2) decreased pod yield of field bean (Vicia faba L. cv. Fuego) by ~30%. Subsequent pot trials, with liming that raised soil pH to 6.3–6.7, reduced stomatal conductance (g s) by 63, 26, and 59% in V. faba, bean (Phaseolus vulgaris), and pea (Pisum sativum), respectively. Furthermore, liming reduced shoot dry biomass by 16–24% in these species. Ionomic analysis of root xylem sap and leaf tissue revealed a decrease in phosphorus concentration that was correlated with decreased g s: both reductions were partially reversed by adding superphosphate fertilizer. Further analysis of pea suggests that leaf gas exchange was reduced by a systemic increase (roots, xylem sap, and leaves) in the phytohormone abscisic acid (ABA) in response to lime-induced suboptimal plant phosphorus concentrations. Supplying synthetic ABA via the transpiration stream to detached pea leaves, at the same xylem sap concentrations induced by liming, decreased transpiration. Furthermore, the g s of the ABA-deficient mutant pea wilty was unresponsive to liming, apparently confirming that ABA mediates some responses to low phosphorus availability caused by liming. This research provides a detailed mechanistic understanding of the physiological processes by which lime application can limit crop yields, and questions the suitability of current liming recommendations. PMID:25740925

  16. Tobacco use is associated with increased plasma BDNF levels in depressed patients.

    PubMed

    Colle, Romain; Trabado, Séverine; Rotenberg, Samuel; Brailly-Tabard, Sylvie; Benyamina, Amine; Aubin, Henri-Jean; Hardy, Patrick; Falissard, Bruno; Becquemont, Laurent; Verstuyft, Céline; Fève, Bruno; Corruble, Emmanuelle

    2016-12-30

    Since serum Brain Derived Neurotrophic Factor (BDNF) levels are higher in tobacco smokers than in non-smokers and since Major Depressive Disorder (MDD) is associated with a 2-fold increased risk of smoking, we assessed the association of smoking and plasma BDNF levels in 359 depressed MDD patients. Plasma BDNF levels were positively correlated with the magnitude of tobacco consumption (current number of cigarettes/day and number of packs/year). Accordingly, current tobacco users had significantly higher plasma BDNF levels than non-users. In further studies of MDD, peripheral measures of BDNF should take into account tobacco use.

  17. Deimination level and peptidyl arginine deiminase 2 expression are elevated in astrocytes with increased incubation temperature.

    PubMed

    Enriquez-Algeciras, Mabel; Bhattacharya, Sanjoy K; Serra, Horacio M

    2015-09-01

    Astrocytes respond to environmental cues, including changes in temperatures. Increased deimination, observed in many progressive neurological diseases, is thought to be contributed by astrocytes. We determined the level of deimination and expression of peptidyl arginine deiminase 2 (PAD2) in isolated primary astrocytes in response to changes on either side (31°C and 41°C) of the optimal temperature (37°C). We investigated changes in the astrocytes by using a number of established markers and accounted for cell death with the CellTiter-Blue assay. We found increased expression of glial fibrillary acidic protein, ALDH1L1, and J1-31, resulting from increased incubation temperature and increased expression of TSP1, S100β, and AQP4, resulting from decreased incubation temperature vs. optimal temperature, suggesting activation of different biochemical pathways in astrocytes associated with different incubation temperatures. Mass spectrometric analyses support such trends. The PAD2 level was increased only as a result of increased incubation temperature with a commensurate increased level of deimination. Actin cytoskeleton and iso[4]LGE, a lipid peroxidase modification, also showed an increase with higher incubation temperature. Altogether, these results suggest that temperature, as an environmental cue, activates astrocytes in a different manner on either side of the optimal temperature and that increase in deimination is associated only with the higher temperature side of the spectrum.

  18. Arsenic increased lipid peroxidation in rat tissues by a mechanism independent of glutathione levels.

    PubMed Central

    Ramos, O; Carrizales, L; Yáñez, L; Mejía, J; Batres, L; Ortíz, D; Díaz-Barriga, F

    1995-01-01

    The role of lipid peroxidation in the mechanism of arsenic toxicity was investigated in female rats pretreated with N-acetylcysteine (NAC, a glutathione [GSH] inducer) or with buthionine sulfoximine (BSO, a GSH depletor). Rats were challenged with sodium arsenite, and sacrificed 1 hr after this treatment. Results showed that arsenic decreased GSH levels and increased lipid peroxidation in liver, kidney, and heart, with a larger effect at 18.2 mg/kg than at 14.8 mg/kg for lipid peroxidation induction. In the liver of rats treated with arsenic, pretreatment with NAC increased the levels of GSH and decreased lipid peroxidation. In kidney and heart, NAC pretreatment protected the tissues against arsenic-induced depletion of GSH levels, but the same degree of protection was not found for lipid peroxidation induction. In its turn, BSO had an additive effect with arsenic in lowering the levels of GSH in the liver and kidney, but an inverse correlation between GSH levels and lipid peroxidation was found only in liver. Arsenic content in tissues of rats pretreated with NAC was lower than in rats treated only with arsenic. In rats with depleted levels of GSH (BSO-pretreated rats), a shift in arsenic tissue distribution was found, with higher levels in skin and lower levels in kidney. A clear tendency for a positive correlation between arsenic concentration and lipid peroxidation levels was found in liver, kidney, and heart. PMID:7621808

  19. 77 FR 36231 - Americans With Disabilities Act (ADA) and Architectural Barriers Act (ABA) Accessibility...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-18

    ... standards for residential facilities are the Uniform Federal Accessibility Standards (UFAS). When HUD... residential facilities covered by the ABA are the Uniform Federal Accessibility Standards (UFAS).\\5\\ HUD...

  20. Increase in Dickkopf-1 Serum Level in Recent Spondyloarthritis. Data from the DESIR Cohort

    PubMed Central

    Nocturne, Gaetane; Pavy, Stephan; Boudaoud, Saida; Seror, Raphaèle; Goupille, Philippe; Chanson, Philippe; van der Heijde, Désirée; van Gaalen, Floris; Berenbaum, Francis; Mariette, Xavier; Briot, Karine; Feydy, Antoine; Claudepierre, Pascal; Dieudé, Philippe; Nithitham, Joanne; Taylor, Kimberly E.; Criswell, Lindsey A.; Dougados, Maxime; Roux, Christian; Miceli-Richard, Corinne

    2015-01-01

    Objectives To investigate DKK-1 and SOST serum levels among patients with recent inflammatory back pain (IBP) fulfilling ASAS criteria for SpA and associated factors. Methods The DESIR cohort is a prospective, multicenter French cohort of 708 patients with early IBP (duration >3 months and <3 years) suggestive of AxSpA. DKK-1 and SOST serum levels were assessed at baseline and were compared between the subgroup of patients fulfilling ASAS criteria for SpA (n = 486; 68.6%) and 80 healthy controls. Results Mean SOST serum levels were lower in ASAS+ patients than healthy controls (49.21 ± 25.9 vs. 87.8 ± 26 pmol/L; p<0.0001). In multivariate analysis, age (p = 5.4 10−9), CRP level (p<0.0001) and serum DKK-1 level (p = 0.001) were associated with SOST level. Mean DKK-1 serum levels were higher in axial SpA patients than controls (30.03 ± 15.5 vs. 11.6 ± 4.2 pmol/L; p<0.0001). In multivariate analysis, DKK-1 serum levels were associated with male gender (p = 0.03), CRP level (p = 0.006), SOST serum level (p = 0.002) and presence of sacroiliitis on radiography (p = 0.05). Genetic association testing of 10 SNPs encompassing the DKK-1 locus failed to demonstrate a significant contribution of genetics to control of DKK-1 serum levels. Conclusions DKK-1 serum levels were increased and SOST levels were decreased among a large cohort of patients with early axial SpA compared to healthy controls. DKK-1 serum levels were mostly associated with biological inflammation and SOST serum levels. PMID:26313358

  1. A Forest Tent Caterpillar Outbreak Increased Resource Levels and Seedling Growth in a Northern Hardwood Forest.

    PubMed

    Rozendaal, Danaë M A; Kobe, Richard K

    2016-01-01

    In closed-canopy forests, gap formation and closure are thought to be major drivers of forest dynamics. Crown defoliation by insects, however, may also influence understory resource levels and thus forest dynamics. We evaluate the effect of a forest tent caterpillar outbreak on understory light availability, soil nutrient levels and tree seedling height growth in six sites with contrasting levels of canopy defoliation in a hardwood forest in northern lower Michigan. We compared resource levels and seedling growth of six hardwood species before, during and in the three years after the outbreak (2008-2012). Canopy openness increased strongly during the forest tent caterpillar outbreak in the four moderately and severely defoliated sites, but not in lightly defoliated sites. Total inorganic soil nitrogen concentrations increased in response to the outbreak in moderately and severely defoliated sites. The increase in total inorganic soil nitrogen was driven by a strong increase in soil nitrate, and tended to become stronger with increasing site defoliation. Seedling height growth increased for all species in the moderately and severely defoliated sites, but not in lightly defoliated sites, either during the outbreak year or in the year after the outbreak. Growth increases did not become stronger with increasing site defoliation, but were strongest in a moderately defoliated site with high soil nutrient levels. Growth increases tended to be strongest for the shade intolerant species Fraxinus americana and Prunus serotina, and the shade tolerant species Ostrya virginiana. The strong growth response of F. americana and P. serotina suggests that recurring forest tent caterpillar outbreaks may facilitate the persistence of shade intolerant species in the understory in the absence of canopy gaps. Overall, our results suggest that recurrent canopy defoliation resulting from cyclical forest insect outbreaks may be an additional driver of dynamics in temperate closed

  2. A Forest Tent Caterpillar Outbreak Increased Resource Levels and Seedling Growth in a Northern Hardwood Forest

    PubMed Central

    Rozendaal, Danaë M. A.; Kobe, Richard K.

    2016-01-01

    In closed-canopy forests, gap formation and closure are thought to be major drivers of forest dynamics. Crown defoliation by insects, however, may also influence understory resource levels and thus forest dynamics. We evaluate the effect of a forest tent caterpillar outbreak on understory light availability, soil nutrient levels and tree seedling height growth in six sites with contrasting levels of canopy defoliation in a hardwood forest in northern lower Michigan. We compared resource levels and seedling growth of six hardwood species before, during and in the three years after the outbreak (2008–2012). Canopy openness increased strongly during the forest tent caterpillar outbreak in the four moderately and severely defoliated sites, but not in lightly defoliated sites. Total inorganic soil nitrogen concentrations increased in response to the outbreak in moderately and severely defoliated sites. The increase in total inorganic soil nitrogen was driven by a strong increase in soil nitrate, and tended to become stronger with increasing site defoliation. Seedling height growth increased for all species in the moderately and severely defoliated sites, but not in lightly defoliated sites, either during the outbreak year or in the year after the outbreak. Growth increases did not become stronger with increasing site defoliation, but were strongest in a moderately defoliated site with high soil nutrient levels. Growth increases tended to be strongest for the shade intolerant species Fraxinus americana and Prunus serotina, and the shade tolerant species Ostrya virginiana. The strong growth response of F. americana and P. serotina suggests that recurring forest tent caterpillar outbreaks may facilitate the persistence of shade intolerant species in the understory in the absence of canopy gaps. Overall, our results suggest that recurrent canopy defoliation resulting from cyclical forest insect outbreaks may be an additional driver of dynamics in temperate closed

  3. Plant responses to drought stress and exogenous ABA application are modulated differently by mycorrhization in tomato and an ABA-deficient mutant (sitiens).

    PubMed

    Aroca, Ricardo; Del Mar Alguacil, Maria; Vernieri, Paolo; Ruiz-Lozano, Juan Manuel

    2008-11-01

    The aims of the present study are to find out whether the effects of arbuscular mycorrhizal (AM) symbiosis on plant resistance to water deficit are mediated by the endogenous abscisic acid (ABA) content of the host plant and whether the exogenous ABA application modifies such effects. The ABA-deficient tomato mutant sitiens and its near-isogenic wild-type parental line were used. Plant development, physiology, and expression of plant genes expected to be modulated by AM symbiosis, drought, and ABA were studied. Results showed that only wild-type tomato plants responded positively to mycorrhizal inoculation, while AM symbiosis was not observed to have any effect on plant development in sitiens plants grown under well-watered conditions. The application of ABA to sitiens plants enhanced plant growth both under well-watered and drought stress conditions. In respect to sitiens plants subjected to drought stress, the addition of ABA had a cumulative effect in relation to that of inoculation with G. intraradices. Most of the genes analyzed in this study showed different regulation patterns in wild-type and sitiens plants, suggesting that their gene expression is modulated by the plant ABA phenotype. In the same way, the colonization of roots with the AM fungus G. intraradices differently regulated the expression of these genes in wild-type and in sitiens plants, which could explain the distinctive effect of the symbiosis on each plant ABA phenotype. This also suggests that the effects of the AM symbiosis on plant responses and resistance to water deficit are mediated by the plant ABA phenotype.

  4. Increase of Hemoglobin Levels by Anti-IL-6 Receptor Antibody (Tocilizumab) in Rheumatoid Arthritis

    PubMed Central

    Hashimoto, Motomu; Fujii, Takao; Hamaguchi, Masahide; Furu, Moritoshi; Ito, Hiromu; Terao, Chikashi; Yamamoto, Keiichi; Yamamoto, Wataru; Matsuo, Takashi; Mori, Masato; Ohmura, Koichiro; Kawabata, Hiroshi; Mimori, Tsuneyo

    2014-01-01

    Objective To compare the effect of tocilizumab (TCZ) with other biologic therapies in improving anemia of rheumatoid arthritis (RA) patients. Methods We compared the change of hemoglobin (Hb) levels in a cohort of 147 consecutive RA patients who were treated with biologics for more than 12 weeks. Twenty eight patients were treated with TCZ, and 119 patients were treated with biologics other than TCZ (87 with TNF inhibitors and 32 with abatacept). The change of Hb levels from baseline to week 12 was compared between the TCZ and the non-TCZ groups. We performed univariate and multivariate analyses with adjustment of potential confounders such as baseline characteristics, concomitant treatment, and the clinical response to treatment. Results Hb levels generally increased after biologic therapies both in the TCZ and the non-TCZ groups. The increase of Hb levels was greater in the TCZ group than in the non-TCZ groups (1.1 g/dL in the TCZ group vs 0.3 g/dL in the non-TCZ group, p = 0.009). Univariate analysis revealed that increase of Hb levels was also significantly associated with lower Hb, higher Low Hemoglobin Density, and higher CRP levels at baseline and greater reduction in the clinical disease activity index. TCZ therapy was significantly associated with the increase of Hb levels even after adjustment for these factors by multivariate analysis (p<0.001, effect size 0.08–0.12). Conclusion TCZ therapy is an independent factor associated with the increase of Hb level after biologic therapies in RA patients. It will help in selecting appropriate biologics for RA patients with anemia. PMID:24878740

  5. Modeling Caspian Sea water level oscillations under different scenarios of increasing atmospheric carbon dioxide concentrations

    PubMed Central

    2012-01-01

    The rapid rise of Caspian Sea water level (about 2.25 meters since 1978) has caused much concern to all five surrounding countries, primarily because flooding has destroyed or damaged buildings and other engineering structures, roads, beaches and farm lands in the coastal zone. Given that climate, and more specifically climate change, is a primary factor influencing oscillations in Caspian Sea water levels, the effect of different climate change scenarios on future Caspian Sea levels was simulated. Variations in environmental parameters such as temperature, precipitation, evaporation, atmospheric carbon dioxide and water level oscillations of the Caspian sea and surrounding regions, are considered for both past (1951-2006) and future (2025-2100) time frames. The output of the UKHADGEM general circulation model and five alternative scenarios including A1CAI, BIASF, BIMES WRE450 and WRE750 were extracted using the MAGICC SCENGEN Model software (version 5.3). The results suggest that the mean temperature of the Caspian Sea region (Bandar-E-Anzali monitoring site) has increased by ca. 0.17°C per decade under the impacts of atmospheric carbon dioxide changes (r=0.21). The Caspian Sea water level has increased by ca. +36cm per decade (r=0.82) between the years 1951-2006. Mean results from all modeled scenarios indicate that the temperature will increase by ca. 3.64°C and precipitation will decrease by ca. 10% (182 mm) over the Caspian Sea, whilst in the Volga river basin, temperatures are projected to increase by ca. 4.78°C and precipitation increase by ca. 12% (58 mm) by the year 2100. Finally, statistical modeling of the Caspian Sea water levels project future water level increases of between 86 cm and 163 cm by the years 2075 and 2100, respectively. PMID:23369617

  6. Modeling Caspian Sea water level oscillations under different scenarios of increasing atmospheric carbon dioxide concentrations.

    PubMed

    Roshan, Gholamreza; Moghbel, Masumeh; Grab, Stefan

    2012-12-12

    The rapid rise of Caspian Sea water level (about 2.25 meters since 1978) has caused much concern to all five surrounding countries, primarily because flooding has destroyed or damaged buildings and other engineering structures, roads, beaches and farm lands in the coastal zone. Given that climate, and more specifically climate change, is a primary factor influencing oscillations in Caspian Sea water levels, the effect of different climate change scenarios on future Caspian Sea levels was simulated. Variations in environmental parameters such as temperature, precipitation, evaporation, atmospheric carbon dioxide and water level oscillations of the Caspian sea and surrounding regions, are considered for both past (1951-2006) and future (2025-2100) time frames. The output of the UKHADGEM general circulation model and five alternative scenarios including A1CAI, BIASF, BIMES WRE450 and WRE750 were extracted using the MAGICC SCENGEN Model software (version 5.3). The results suggest that the mean temperature of the Caspian Sea region (Bandar-E-Anzali monitoring site) has increased by ca. 0.17°C per decade under the impacts of atmospheric carbon dioxide changes (r=0.21). The Caspian Sea water level has increased by ca. +36cm per decade (r=0.82) between the years 1951-2006. Mean results from all modeled scenarios indicate that the temperature will increase by ca. 3.64°C and precipitation will decrease by ca. 10% (182 mm) over the Caspian Sea, whilst in the Volga river basin, temperatures are projected to increase by ca. 4.78°C and precipitation increase by ca. 12% (58 mm) by the year 2100. Finally, statistical modeling of the Caspian Sea water levels project future water level increases of between 86 cm and 163 cm by the years 2075 and 2100, respectively.

  7. Elevated Plasma Homocysteine Level Increased the Risk of Early Renal Impairment in Acute Ischemic Stroke Patients.

    PubMed

    Chen, Jingjuan; Li, Guode; Xu, Zuohang; Zhang, Chengguo; Wang, Yukai; Xie, Haiqun; Shao, Yan; Peng, Lingmei; Lu, Jiancong; Yuan, Dahua

    2017-03-08

    Renal insufficiency is associated with the prognosis of acute ischemic stroke (AIS) and homocysteine (Hcy) levels. This study investigated the association between plasma Hcy levels and renal insufficiency in patients with AIS. A total of 987 patients with AIS who had been treated at the First People's Hospital of Foshan between 2011 and 2014 were retrospectively studied. Based on their cystatin C (Cys C) levels, the patients were divided into the normal renal function group (Cys C ≤ 1.25 mg/L) or the renal impairment group (Cys C > 1.25 mg/L). Multivariate regression analysis was applied to reveal the association between hyperhomocysteinemia (HHcy) and renal impairment. The renal impairment group showed more advanced age of onset, higher percentage of prior stroke and hypertension, higher baseline National Institute of Health Stroke Scale score, lower high-density lipoprotein cholesterol levels, and higher Hcy levels compared with the normal renal function group. A multivariate analysis revealed a relationship between early renal impairment and Hcy levels: an increase of Hcy by 1 μmol/L was associated with an increase of 12-18% of the risk of renal impairment among patients with AIS and HHcy. Patients with AIS and HHcy had a 2.42-3.51 fold increase of the risk of renal impairment compared with patients with normal Hcy level (P < 0.001). In conclusion, patients with stroke and HHcy could be more prone to renal impairment.

  8. Chronic lamotrigine treatment increases rat hippocampal GABA shunt activity and elevates cerebral taurine levels.

    PubMed

    Hassel, B; Taubøll, E; Gjerstad, L

    2001-02-01

    The mechanism of action of the antiepileptic drug lamotrigine has previously been investigated only in acute experiments and is thought to involve inhibition of voltage-dependent sodium channels. However, lamotrigine is effective against more forms of epilepsies than other antiepileptic drugs that also inhibit sodium channels. We investigated whether chronic lamotrigine treatment may affect cerebral amino acid levels. Rats received lamotrigine, 10 mg/kg/day, for 90 days. The hippocampal level of GABA increased 25%, and the activities of glutamate decarboxylase and succinic semialdehyde/GABA transaminase increased 12 and 21% (p< 0.05), respectively, indicating increased GABA turnover. The uptake of GABA and glutamate into proteoliposomes remained unaltered. The level of taurine increased 27% in the hippocampus and 16% in the frontal and parietal cortices. The activities of hexokinase and alpha-ketoglutarate dehydrogenase, remained at control values. Serum lamotrigine was 41.7+/-1.5 microM (mean+/-S.E.M.), which is within the range seen in epileptic patients. Acute experiments with 5, 20 or 100 mg lamotrigine/kg, caused no changes in brain amino acid levels. The results suggest that chronic lamotrigine treatment increases GABAergic activity in the hippocampus. The cerebral increase in taurine, which has neuromodulatory properties, may contribute to the antiepileptic effect of lamotrigine.

  9. SlNCED1 and SlCYP707A2: key genes involved in ABA metabolism during tomato fruit ripening.

    PubMed

    Ji, Kai; Kai, Wenbin; Zhao, Bo; Sun, Yufei; Yuan, Bing; Dai, Shengjie; Li, Qian; Chen, Pei; Wang, Ya; Pei, Yuelin; Wang, Hongqing; Guo, Yangdong; Leng, Ping

    2014-10-01

    Abscisic acid (ABA) plays an important role in fruit development and ripening. Here, three NCED genes encoding 9-cis-epoxycarotenoid dioxygenase (NCED, a key enzyme in the ABA biosynthetic pathway) and three CYP707A genes encoding ABA 8'-hydroxylase (a key enzyme in the oxidative catabolism of ABA) were identified in tomato fruit by tobacco rattle virus-induced gene silencing (VIGS). Quantitative real-time PCR showed that VIGS-treated tomato fruits had significant reductions in target gene transcripts. In SlNCED1-RNAi-treated fruits, ripening slowed down, and the entire fruit turned to orange instead of red as in the control. In comparison, the downregulation of SlCYP707A2 expression in SlCYP707A2-silenced fruit could promote ripening; for example, colouring was quicker than in the control. Silencing SlNCED2/3 or SlCYP707A1/3 made no significant difference to fruit ripening comparing RNAi-treated fruits with control fruits. ABA accumulation and SlNCED1transcript levels in the SlNCED1-RNAi-treated fruit were downregulated to 21% and 19% of those in control fruit, respectively, but upregulated in SlCYP707A2-RNAi-treated fruit. Silencing SlNCED1 or SlCYP707A2 by VIGS significantly altered the transcripts of a set of both ABA-responsive and ripening-related genes, including ABA-signalling genes (PYL1, PP2C1, and SnRK2.2), lycopene-synthesis genes (SlBcyc, SlPSY1 and SlPDS), and cell wall-degrading genes (SlPG1, SlEXP, and SlXET) during ripening. These data indicate that SlNCED1 and SlCYP707A2 are key genes in the regulation of ABA synthesis and catabolism, and are involved in fruit ripening as positive and negative regulators, respectively.

  10. Increased Heme Levels in the Heart Lead to Exacerbated Ischemic Injury

    PubMed Central

    Sawicki, Konrad Teodor; Shang, Meng; Wu, Rongxue; Chang, Hsiang-Chun; Khechaduri, Arineh; Sato, Tatsuya; Kamide, Christine; Liu, Ting; Naga Prasad, Sathyamangla V; Ardehali, Hossein

    2015-01-01

    Background Heme is an essential iron-containing molecule for cardiovascular physiology, but in excess it may increase oxidative stress. Failing human hearts have increased heme levels, with upregulation of the rate-limiting enzyme in heme synthesis, δ-aminolevulinic acid synthase 2 (ALAS2), which is normally not expressed in cardiomyocytes. We hypothesized that increased heme accumulation (through cardiac overexpression of ALAS2) leads to increased oxidative stress and cell death in the heart. Methods and Results We first showed that ALAS2 and heme levels are increased in the hearts of mice subjected to coronary ligation. To determine the causative role of increased heme in the development of heart failure, we generated transgenic mice with cardiac-specific overexpression of ALAS2. While ALAS2 transgenic mice have normal cardiac function at baseline, their hearts display increased heme content, higher oxidative stress, exacerbated cell death, and worsened cardiac function after coronary ligation compared to nontransgenic littermates. We confirmed in cultured cardiomyoblasts that the increased oxidative stress and cell death observed with ALAS2 overexpression is mediated by increased heme accumulation. Furthermore, knockdown of ALAS2 in cultured cardiomyoblasts exposed to hypoxia reversed the increases in heme content and cell death. Administration of the mitochondrial antioxidant MitoTempo to ALAS2-overexpressing cardiomyoblasts normalized the elevated oxidative stress and cell death levels to baseline, indicating that the effects of increased ALAS2 and heme are through elevated mitochondrial oxidative stress. The clinical relevance of these findings was supported by the finding of increased ALAS2 induction and heme accumulation in failing human hearts from patients with ischemic cardiomyopathy compared to nonischemic cardiomyopathy. Conclusions Heme accumulation is detrimental to cardiac function under ischemic conditions, and reducing heme in the heart may be a

  11. High D-dimer levels increase the likelihood of pulmonary embolism.

    PubMed

    Tick, L W; Nijkeuter, M; Kramer, M H H; Hovens, M M C; Büller, H R; Leebeek, F W G; Huisman, M V

    2008-08-01

    Objective. To determine the utility of high quantitative D-dimer levels in the diagnosis of pulmonary embolism. Methods. D-dimer testing was performed in consecutive patients with suspected pulmonary embolism. We included patients with suspected pulmonary embolism with a high risk for venous thromboembolism, i.e. hospitalized patients, patients older than 80 years, with malignancy or previous surgery. Presence of pulmonary embolism was based on a diagnostic management strategy using a clinical decision rule (CDR), D-dimer testing and computed tomography. Results. A total of 1515 patients were included with an overall pulmonary embolism prevalence of 21%. The pulmonary embolism prevalence was strongly associated with the height of the D-dimer level, and increased fourfold with D-dimer levels greater than 4000 ng mL(-1) compared to levels between 500 and 1000 ng mL(-1). Patients with D-dimer levels higher than 2000 ng mL(-1) and an unlikely CDR had a pulmonary embolism prevalence of 36%. This prevalence is comparable to the pulmonary embolism likely CDR group. When D-dimer levels were above 4000 ng mL(-1), the observed pulmonary embolism prevalence was very high, independent of CDR score. Conclusion. Strongly elevated D-dimer levels substantially increase the likelihood of pulmonary embolism. Whether this should translate into more intensive diagnostic and therapeutic measures in patients with high D-dimer levels irrespective of CDR remains to be studied.

  12. Brief Report: Impact of Applied Behaviour Analysis (ABA) on Carer Burden and Community Participation in Challenging Behaviour--Results from a Randomised Controlled Trial

    ERIC Educational Resources Information Center

    Hassiotis, A.; Robotham, D.; Canagasabey, A.; Marston, L.; Thomas, B.; King, M.

    2012-01-01

    Background: Applied behaviour analysis (ABA) reduces challenging behaviour in people with intellectual disability. There is interest, however, in whether such interventions reduce carer burden and increase community participation in this group. Methods: A 6-month randomised controlled trial was followed by a longer-term naturalistic follow-up of…

  13. Nutrient levels modify saltmarsh responses to increased inundation in different soil types.

    PubMed

    Wong, Joanne X W; Van Colen, Carl; Airoldi, Laura

    2015-03-01

    Saltmarshes have been depleted historically, and cumulative stressors threaten their future persistence. We examined experimentally how nutrient availability (high vs. low) affects the responses of Spartina maritima to increased inundation in two mineral soil types (low vs. medium organic). Increased inundation, one of the effects of accelerated sea level rise, had negative effects on most plant growth parameters, but the magnitude varied with soil and nutrient levels, and between plants from different locations. Average differences between inundation treatments were largest at high nutrient conditions in low organic matter soils. We conclude that saltmarsh vegetation would be more drastically affected by increased inundation in low than in medium organic matter soils, and especially in estuaries already under high nutrient availability. This knowledge enhances the prediction of changes at the foreshore of saltmarshes related to sea level rise, and the development of site-specific conservation strategies.

  14. New cross talk between ROS, ABA and auxin controlling seed maturation and germination unraveled in APX6 deficient Arabidopsis seeds.

    PubMed

    Chen, Changming; Twito, Shir; Miller, Gad

    2014-01-01

    Successful execution of germination program greatly depends on the seeds' oxidative homeostasis. We recently identified new roles for the H2O2-reducing enzyme ascorbate peroxidase 6 (APX6) in germination control and seeds' stress tolerance. APX6 replaces APX1 as the dominant APX in dry seeds, and its loss-of-function results in reduced germination due to over accumulation of ROS and oxidative damage. Metabolic analyses in dry apx6 seeds, revealed altered homeostasis of primary metabolites including accumulation of TCA cycle metabolites, ABA and auxin, supporting a novel role for APX6 in regulating cellular metabolism. Increased sensitivity of apx6 mutants to ABA or IAA in germination assays indicated impaired perception of these signals. Relative suppression of ABI3 and ABI5 expression, and induction of ABI4, suggested the activation of a signaling route inhibiting germination in apx6 seeds that is independent of ABI3. Here we provide additional evidence linking ABI4 with ABA- and auxin-controlled inhibition of germination and suggest a hypothetical model for the role of APX6 in the regulation of the crosstalk between these hormones and ROS.

  15. Anesthetic Isoflurane Increases Phosphorylated Tau Levels Mediated by Caspase Activation and Aβ Generation

    PubMed Central

    Dong, Yuanlin; Wu, Xu; Xu, Zhipeng; Zhang, Yiying; Xie, Zhongcong

    2012-01-01

    Anesthetic isoflurane has been shown to promote Alzheimer’s disease (AD) neuropathogenesis by inducing caspase activation and accumulation of β-amyloid (Aβ). Phosphorylation of tau protein is another important feature of AD neuropathogenesis. However, the effects of isoflurane on phosphorylated tau levels remain largely to be determined. We therefore set out to determine whether isoflurane can increase phosphorylated tau levels. 5 to 8 month-old wild-type and AD transgenic mice [B6.Cg-Tg (APPswe, PSEN1dE9)85Dbo/J] were treated with 1.4% isoflurane for two hours. The mice brain tissues were harvested at six, 12 and 24 hours after the anesthesia. For the in vitro studies, primary neurons from wild-type and the AD transgenic mice were exposed to 2% isoflurane for six hours, and were harvested at the end of anesthesia. The harvested brain tissues and neurons were subjected to Western blot analysis by which the levels of phosphorylated tau protein at Serine 262 (Tau-PS262) were determined. Here we show that the isoflurane anesthesia increased Tau-PS262 levels in brain tissues and primary neurons from the wild-type and AD transgenic mice. Moreover, the isoflurane anesthesia may induce a greater increase in Tau-PS262 levels in primary neurons and brain tissues from the AD transgenic mice. Finally, caspase activation inhibitor Z-VAD and Aβ generation inhibitor L-685,458 attenuated the isoflurane-induced increases in Tau-PS262 levels. In conclusion, clinically relevant isoflurane anesthesia increases phosphorylated tau levels, which may result from the isoflurane-induced caspase activation and Aβ generation. These findings will promote more studies to determine the effects of anesthetics on tau phosphorylation. PMID:22745746

  16. Calpain expression in lymphoid cells. Increased mRNA and protein levels after cell activation.

    PubMed

    Deshpande, R V; Goust, J M; Chakrabarti, A K; Barbosa, E; Hogan, E L; Banik, N L

    1995-02-10

    Although calpain is ubiquitously present in human tissues and is thought to play a role in demyelination, its activity is very low in resting normal lymphocytes. To determine the nature of calpain expression at the mRNA and protein levels in human lymphoid cells, we studied human T lymphocytic, B lymphocytic, and monocytic lines as well as peripheral blood mononuclear cells. Stimulation of cells with the phorbol ester phorbol myristate acetate and the calcium ionophore A23187 resulted in increased calpain mRNA and protein expression. Calpain mRNA expression is also increased in human T cells stimulated with anti-CD3. A dissociation between the increases of RNA and protein suggested that calpain could be released from the cells; the subsequent experiments showed its presence in the extracellular environment. 5,6-Dichloro-1b-D-ribofuranosylbenzimidazole, a reversible inhibitor of mRNA synthesis, reduced calpain mRNA levels by 50-67% and protein levels by 72-91%. Its removal resulted in resumption of both calpain mRNA and protein synthesis. Cycloheximide, a translational inhibitor, reduced calpain protein levels by 77-81% and calpain mRNA levels by 96% in activated THP-1 cells. Interferon-gamma induced calpain mRNA and protein in U-937 and THP-1 cells. Dexamethasone increased mRNA expression in THP-1 cells. Our results indicate that activation of lymphoid cells results in de novo synthesis and secretion of calpain.

  17. Methylglyoxal increases dopamine level and leads to oxidative stress in SH-SY5Y cells.

    PubMed

    Xie, Bingjie; Lin, Fankai; Peng, Lei; Ullah, Kaleem; Wu, Hanyan; Qing, Hong; Deng, Yulin

    2014-11-01

    More and more studies have suggested that methylglyoxal (MGO) induced by type-2 diabetes is related to Parkinson's disease (PD). However, little is known about the molecular mechanism. In this study, we explored the MGO toxicity in neuroblastoma SH-SY5Y cells. Neurotoxicity of MGO was measured by mitochondrial membrane potential, malondialdehyde, and methylthiazoletetrazolium assays. The levels of dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC), and 1-methyl-4-phenyl-1,2,3,4-tetrahydroisoquinoline (salsolinol) were detected by liquid chromatography-mass spectrometry/mass spectrometry. The expressions of tyrosine hydroxylase (TH) and dopamine transporter (DAT) were detected by reverse transcriptase polymerase chain reaction and western blot analysis. The results showed that MGO induced an increase in TH and DAT expressions in SH-SY5Y neuroblastoma cells, while the levels of dopamine, DOPAC, and endogenous neurotoxin salsolinol also increased. Aminoguanidine (AG) is an inhibitor of MGO. It was found that AG could decrease the reactive oxygen species (ROS) level induced by MGO, but could not inhibit an increase of TH, DAT and dopamine. The increase of dopamine, DOPAC and salsolinol levels could lead to high ROS and mitochondrial damage. This study suggests that ROS caused by dopamine could contribute to the damage of dopaminergic neurons when MGO is increased during the course of diabetes.

  18. Acute psychological stress increases plasma levels of cortisol, prolactin and TSH.

    PubMed

    Schedlowski, M; Wiechert, D; Wagner, T O; Tewes, U

    1992-01-01

    The effects of acute stress during a parachute jump on hormonal responses were studied in 12 experienced and 11 inexperienced military parachutists. Each subject performed two jumps. Prior to and immediately after each jump blood samples were drawn and analysed for plasma levels of cortisol, prolactin, thyrotropin (TSH), somatotropin (STH), and luteinizing hormone (LH). While there was a significant increase in cortisol, prolactin and TSH levels after both jumps, no alterations could be observed in STH and LH levels. Stress-induced hormonal responses were not affected by jump experience. There was also no association between the endocrine variables and anxiety scores.

  19. Serum Resistin Levels May Contribute to an Increased Risk of Acute Cerebral Infarction.

    PubMed

    Dong, Xiao-Liu; Xu, Shi-Jun; Zhang, Li; Zhang, Xiu-Qing; Liu, Ting; Gao, Qiu-Yan; Qian, Qing-Qiang; Sun, Bao-Liang; Yang, Ming-Feng

    2017-04-01

    The objective of this study was to investigate the association between serum resistin levels and acute cerebral infarction (ACI). PubMed, SpringerLink, Wiley, EBSCO, Ovid, Web of Science, Wanfang, China National Knowledge Infrastructure, and VIP databases (last updated search in October 2014) were exhaustively searched, and data from the eligible studies were extracted and analyzed to assess the association between serum resistin levels and ACI. STATA software (version 12.0, Stata Corporation, College Station, TX, USA) was utilized for data analysis. Ten studies including 1829 ACI patients and 1557 healthy controls were eligible for inclusion in the meta-analysis. Our major result revealed that ACI patients exhibited higher serum resistin levels compared with healthy controls. Asubgroup analysis based on ethnicity showed a significant association between serum resistin levels and ACI in Asians, but surprisingly not in Caucasians. The results of our meta-analysis suggest that serum resistin levels are associated with an increased risk of ACI.

  20. A rapid increase in lipoprotein (a) levels after ethanol withdrawal in alcoholic men

    SciTech Connect

    Kervinen, K.; Savolainen, J.J.; Kesaeniemi, Y.A. )

    1991-01-01

    Plasma concentrations of lipoprotein (a) (Lp(a)) were studied in 11 male alcoholics at the end of a drinking period and monitored during subsequent abstinence. Lp(a) levels showed a daily increase for four consecutive days after the beginning of abstinence, the values for the third and the fourth day being significantly higher than those of the first day. The changes in Lp(a) showed no association with the changes in low density lipoprotein (LDL) and high density lipoprotein (HDL) cholesterol levels. In one alcoholic subject with a heterozygous form of familial hypercholesterolemia who was monitored for 11 days, the Lp(a) levels rose up to the fourth day and remained at a high level thereafter. These results suggest that ethanol ingestion may be associated with a lower of Lp(a) levels, which may contribute to the delayed progression of atherosclerosis observed in alcohol drinkers.

  1. Increased FGF21 plasma levels in humans with sepsis and SIRS.

    PubMed

    Gariani, Karim; Drifte, Geneviève; Dunn-Siegrist, Irène; Pugin, Jérôme; Jornayvaz, François R

    2013-01-01

    Fibroblast growth factor 21 (FGF21) is a key regulator in glucose and lipid metabolism and its plasma levels have been shown to be increased not only in humans in different situations such as type 2 diabetes, obesity, and nonalcoholic fatty liver disease but also in animal models of sepsis and pancreatitis. FGF21 is considered as a pharmacological candidate in conditions associated with insulin resistance. The aim of this study was to compare FGF21 plasma levels in patients with sepsis, in patients with systemic inflammatory response syndrome (SIRS), and in healthy controls. We measured FGF21 plasma concentrations in 22 patients with established sepsis, in 11 with SIRS, and in 12 healthy volunteers. Here, we show that FGF21 levels were significantly higher in plasma obtained from patients with sepsis and SIRS in comparison with healthy controls. Also, FGF21 levels were significantly higher in patients with sepsis than in those with noninfectious SIRS. FGF21 plasma levels measured at study entry correlated positively with the APACHE II score, but not with procalcitonin levels, nor with C-reactive protein, classical markers of sepsis. Plasma concentrations of FGF21 peaked near the onset of shock and rapidly decreased with clinical improvement. Taken together, these results indicate that circulating levels of FGF21 are increased in patients presenting with sepsis and SIRS, and suggest a role for FGF21 in inflammation. Further studies are needed to explore the potential role of FGF21 in sepsis as a potential therapeutic target.

  2. The Citrus ABA signalosome: identification and transcriptional regulation during sweet orange fruit ripening and leaf dehydration

    PubMed Central

    Rodrigo, María J.

    2012-01-01

    The abscisic acid (ABA) signalling core in plants include the cytosolic ABA receptors (PYR/PYL/RCARs), the clade-A type 2C protein phosphatases (PP2CAs), and the subclass III SNF1-related protein kinases 2 (SnRK2s). The aim of this work was to identify these ABA perception system components in sweet orange and to determine the influence of endogenous ABA on their transcriptional regulation during fruit development and ripening, taking advantage of the comparative analysis between a wild-type and a fruit-specific ABA-deficient mutant. Transcriptional changes in the ABA signalosome during leaf dehydration were also studied. Six PYR/PYL/RCAR, five PP2CA, and two subclass III SnRK2 genes, homologous to those of Arabidopsis, were identified in the Citrus genome. The high degree of homology and conserved motifs for protein folding and for functional activity suggested that these Citrus proteins are bona fide core elements of ABA perception in orange. Opposite expression patterns of CsPYL4 and CsPYL5 and ABA accumulation were found during ripening, although there were few differences between varieties. In contrast, changes in expression of CsPP2CA genes during ripening paralleled those of ABA content and agreeed with the relevant differences between wild-type and mutant fruit transcript accumulation. CsSnRK2 gene expression continuously decreased with ripening and no remarkable differences were found between cultivars. Overall, dehydration had a minor effect on CsPYR/PYL/RCAR and CsSnRK2 expression in vegetative tissue, whereas CsABI1, CsAHG1, and CsAHG3 were highly induced by water stress. The global results suggest that responsiveness to ABA changes during citrus fruit ripening, and leaf dehydration was higher in the CsPP2CA gene negative regulators than in the other ABA signalosome components. PMID:22888124

  3. Increased matrix metalloproteinase-3 serum levels in rheumatic diseases: relationship with synovitis and steroid treatment

    PubMed Central

    Ribbens, C; Martin, y; Franchimont, N; Kaiser, M; Jaspar, J; Damas, P; Houssiau, F; Malaise, M

    2002-01-01

    Objective: To determine matrix metalloproteinase-3 (MMP-3) serum levels in patients with rheumatic diseases and to study the relation between MMP-3 and C reactive protein (CRP) levels. Methods: MMP-3 serum levels were determined by enzyme linked immunosorbent assay (ELISA) in (a) patients with active inflammatory rheumatic diseases: rheumatoid arthritis (RA), psoriatic arthritis, polymyalgia rheumatica, acute crystal arthritis, and ankylosing spondylitis; (b) patients with active inflammatory systemic diseases: cutaneo-articular or renal systemic lupus erythematosus (SLE), systemic sclerosis, and vasculitides; (c) patients with non-inflammatory rheumatic diseases: osteoarthritis and fibromyalgia; (d) critically ill patients without rheumatic diseases, representing an acute inflammatory control group; (e) healthy controls. Results: MMP-3 serum levels were significantly increased in patients with active RA, psoriatic arthritis, and polymyalgia rheumatica, whether treated or not by corticosteroids, and in female patients with acute crystal arthritis. MMP-3 serum levels were normal in steroid-free patients with active cutaneo-articular or renal SLE, systemic sclerosis, and vasculitides but were significantly increased in steroid treated patients. MMP-3 levels were normal in fibromyalgia, osteoarthritis, ankylosing spondylitis, and acute inflammatory controls. MMP-3 was significantly correlated with CRP in RA (r=0.5, p=0.0004) but not in any of the other disease groups. Conclusions: MMP-3 serum levels are increased in inflammatory rheumatic diseases characterised by joint synovitis, such as RA, polymyalgia rheumatica, psoriatic arthritis, and acute crystal arthritis—that is, whether the diseases are acute or chronic, erosive or not. They are normal in SLE, systemic sclerosis, and vasculitides as well as in non-rheumatic inflammatory controls, but are significantly increased by steroids. These data strongly suggest that serum MMP-3 reflects synovial inflammation. PMID

  4. Projected carbon dioxide to increase grass pollen and allergen exposure despite higher ozone levels.

    PubMed

    Albertine, Jennifer M; Manning, William J; DaCosta, Michelle; Stinson, Kristina A; Muilenberg, Michael L; Rogers, Christine A

    2014-01-01

    One expected effect of climate change on human health is increasing allergic and asthmatic symptoms through changes in pollen biology. Allergic diseases have a large impact on human health globally, with 10-30% of the population affected by allergic rhinitis and more than 300 million affected by asthma. Pollen from grass species, which are highly allergenic and occur worldwide, elicits allergic responses in 20% of the general population and 40% of atopic individuals. Here we examine the effects of elevated levels of two greenhouse gases, carbon dioxide (CO2), a growth and reproductive stimulator of plants, and ozone (O3), a repressor, on pollen and allergen production in Timothy grass (Phleum pratense L.). We conducted a fully factorial experiment in which plants were grown at ambient and/or elevated levels of O3 and CO2, to simulate present and projected levels of both gases and their potential interactive effects. We captured and counted pollen from flowers in each treatment and assayed for concentrations of the allergen protein, Phl p 5. We found that elevated levels of CO2 increased the amount of grass pollen produced by ∼50% per flower, regardless of O3 levels. Elevated O3 significantly reduced the Phl p 5 content of the pollen but the net effect of rising pollen numbers with elevated CO2 indicate increased allergen exposure under elevated levels of both greenhouse gases. Using quantitative estimates of increased pollen production and number of flowering plants per treatment, we estimated that airborne grass pollen concentrations will increase in the future up to ∼200%. Due to the widespread existence of grasses and the particular importance of P. pratense in eliciting allergic responses, our findings provide evidence for significant impacts on human health worldwide as a result of future climate change.

  5. Proteomic analyses reveal the key roles of BrlA and AbaA in biogenesis of gliotoxin in Aspergillus fumigatus

    SciTech Connect

    Shin, Kwang-Soo; Kim, Young Hwan; Yu, Jae-Hyuk

    2015-07-31

    The opportunistic human pathogenic fungus Aspergillus fumigatus primarily reproduces by forming a large number of asexual spores (conidia). Sequential activation of the central regulators BrlA, AbaA and WetA is necessary for the fungus to undergo asexual development. In this study, to address the presumed roles of these key developmental regulators during proliferation of the fungus, we analyzed and compared the proteomes of vegetative cells of wild type (WT) and individual mutant strains. Approximately 1300 protein spots were detectable from 2-D electrophoresis gels. Among these, 13 proteins exhibiting significantly altered accumulation levels were further identified by ESI-MS/MS. Markedly, we found that the GliM and GliT proteins associated with gliotoxin (GT) biosynthesis and self-protection of the fungus from GT were significantly down-regulated in the ΔabaA and ΔbrlA mutants. Moreover, mRNA levels of other GT biosynthetic genes including gliM, gliP, gliT, and gliZ were significantly reduced in both mutant strains, and no and low levels of GT were detectable in the ΔbrlA and ΔabaA mutant strains, respectively. As GliT is required for the protection of the fungus from GT, growth of the ΔbrlA mutant with reduced levels of GliT was severely impaired by exogenous GT. Our studies demonstrate that AbaA and BrlA positively regulate expression of the GT biosynthetic gene cluster in actively growing vegetative cells, and likely bridge morphological and chemical development during the life-cycle of A. fumigatus. - Highlights: • Proteome analyses of WT and mutants reveal 13 differentially expressed proteins. • The GliT and GliM proteins are significantly down-regulated by ΔabaA and ΔbrlA. • Expression of other gliotoxin biosynthetic genes is lowered by ΔabaA and ΔbrlA. • Growth of ΔbrlA strain lacking GliT is completely inhibited by exogenous gliotoxin. • BrlA and AbaA play key roles in biogenesis of gliotoxin in Aspergillus fumigatus.

  6. The number of preproghrelin mRNA expressing cells is increased in mice with activity-based anorexia.

    PubMed

    François, Marie; Barde, Swapnali; Achamrah, Najate; Breton, Jonathan; do Rego, Jean-Claude; Coëffier, Moïse; Hökfelt, Tomas; Déchelotte, Pierre; Fetissov, Sergueï O

    2015-06-01

    Plasma levels of ghrelin, an orexigenic peptide, are increased during conditions of chronic starvation, such as in patients with anorexia nervosa. However, it is not known whether such increase can be related to the number of preproghrelin mRNA-expressing cells in the stomach, and if chronic starvation may activate a tentative central ghrelin production. In this work, in situ hybridization technique was used to analyze the presence and number of preproghrelin mRNA-expressing cells in the stomach and the hypothalamus of mice with activity-based anorexia (ABA) induced by the combination of running wheel activity with progressive, during 10 days, feeding-time restriction (FTR) and compared with sedentary FTR, ABA pair-fed (PF) and ad libitum-fed control mice. All food-restricted mice lost more than 20% of body weight. Body weight loss was similar in ABA and PF mice, but it was more pronounced than in FTR mice. Food intake was also lower in ABA than in FTR mice. Preproghrelin mRNA-expressing cells in the stomach were increased proportionally to the body weight loss in all food-restricted groups with the highest number in ABA mice. No preproghrelin mRNA-producing cells were detectable in the hypothalamus of either control or food-restricted mice. Thus, the increased number of gastric preproghrelin mRNA-producing cells during chronic starvation proportionally to the body weight loss and reduced food intake may underlie increased plasma ghrelin. Hyperactivity-induced anorexia appears to further increase the number of preproghrelin mRNA-producing cells in the stomach. No evidence was found for ghrelin expression in the hypothalamus, not even in any of the present experimental models.

  7. Short communication: artificial ultraviolet B light exposure increases vitamin D levels in cow plasma and milk.

    PubMed

    Jakobsen, Jette; Jensen, Søren Krogh; Hymøller, Lone; Andersen, Elisabeth Wreford; Kaas, Poul; Burild, Anders; Jäpelt, Rie Bak

    2015-09-01

    The number of dairy cows without access to pasture or sunlight is increasing; therefore, the content of vitamin D in dairy products is decreasing. Ultimately, declining vitamin D levels in dairy products will mean that dairy products are a negligible source of natural vitamin D for humans. We tested the ability of a specially designed UVB lamp to enhance the vitamin D3 content in milk from dairy cows housed indoors. This study included 16 cows divided into 4 groups. Each group was exposed daily to artificial UVB light simulating 1, 2, 3, or 4 h of summer sun at 56°N for 24 d, and the group with simulated exposure to 2 h of summer sun daily continued to be monitored for 73 d. We found a significant increase in 25-hydroxyvitamin D3 (25OHD3) levels in plasma as well as vitamin D3 and 25OHD3 levels in milk after daily exposure for 24 d in all treatment groups. Extending daily exposure to artificial UVB light to 73 d did not lead to an increase of vitamin D3 or 25OHD3 level in the milk. In conclusion, the change in production facilities for dairy cows providing cows with no access to pasture and sunlight causes a decrease of vitamin D levels in dairy products. This decrease may be prevented by exposing cows to artificial UVB light in the stable.

  8. Bilirubin Increases Insulin Sensitivity by Regulating Cholesterol Metabolism, Adipokines and PPARγ Levels.

    PubMed

    Liu, Jinfeng; Dong, Huansheng; Zhang, Yong; Cao, Mingjun; Song, Lili; Pan, Qingjie; Bulmer, Andrew; Adams, David B; Dong, Xiao; Wang, Hongjun

    2015-05-28

    Obesity can cause insulin resistance and type 2 diabetes. Moderate elevations in bilirubin levels have anti-diabetic effects. This study is aimed at determining the mechanisms by which bilirubin treatment reduces obesity and insulin resistance in a diet-induced obesity (DIO) mouse model. DIO mice were treated with bilirubin or vehicle for 14 days. Body weights, plasma glucose, and insulin tolerance tests were performed prior to, immediately, and 7 weeks post-treatment. Serum lipid, leptin, adiponectin, insulin, total and direct bilirubin levels were measured. Expression of factors involved in adipose metabolism including sterol regulatory element-binding protein (SREBP-1), insulin receptor (IR), and PPARγ in liver were measured by RT-PCR and Western blot. Compared to controls, bilirubin-treated mice exhibited reductions in body weight, blood glucose levels, total cholesterol (TC), leptin, total and direct bilirubin, and increases in adiponectin and expression of SREBP-1, IR, and PPARγ mRNA. The improved metabolic control achieved by bilirubin-treated mice was persistent: at two months after treatment termination, bilirubin-treated DIO mice remained insulin sensitive with lower leptin and higher adiponectin levels, together with increased PPARγ expression. These results indicate that bilirubin regulates cholesterol metabolism, adipokines and PPARγ levels, which likely contribute to increased insulin sensitivity and glucose tolerance in DIO mice.

  9. Increased levels of 4-hydroxynonenal and acrolein in the brain in preclinical Alzheimer disease.

    PubMed

    Bradley, M A; Markesbery, W R; Lovell, M A

    2010-06-15

    Previous studies demonstrate increased levels of 4-hydroxynonenal (HNE) and acrolein in vulnerable brain regions of subjects with mild cognitive impairment and late-stage Alzheimer disease (LAD). Recently preclinical AD (PCAD) subjects, who demonstrate normal antemortem neuropsychological test scores but abundant AD pathology at autopsy, have become the focus of increased study. Levels of extractable HNE and acrolein were quantified by gas chromatography-mass spectrometry with negative chemical ionization, and protein-bound HNE and acrolein were quantified by dot-blot immunohistochemistry in the hippocampus/parahippocampal gyrus (HPG), superior and middle temporal gyri (SMTG), and cerebellum (CER) of 10 PCAD and 10 age-matched normal control (NC) subjects. Results of the analyses show a significant (P<0.05) increase in levels of extractable acrolein in the HPG of PCAD subjects compared to age-matched NC subjects and a significant decrease in extractable acrolein in PCAD CER. Significant increases in protein-bound HNE in HPG and a significant decrease in CER of PCAD subjects compared to NC subjects were observed. No significant alterations were observed in either extractable or protein-bound HNE or acrolein in the SMTG of PCAD subjects. Additionally, no significant differences in levels of protein carbonyls were observed in the HPG, SMTG, or CER of PCAD subjects compared to NC subjects.

  10. Increasing levels of cardiolipin differentially influence packing of phospholipids found in the mitochondrial inner membrane.

    PubMed

    Zeczycki, Tonya N; Whelan, Jarrett; Hayden, William Tyler; Brown, David A; Shaikh, Saame Raza

    2014-07-18

    It is essential to understand the role of cardiolipin (CL) in mitochondrial membrane organization given that changes in CL levels contribute to mitochondrial dysfunction in type II diabetes, ischemia-reperfusion injury, heart failure, breast cancer, and aging. Specifically, there are contradictory data on how CL influences the molecular packing of membrane phospholipids. Therefore, we determined how increasing levels of heart CL impacted molecular packing in large unilamellar vesicles, modeling heterogeneous lipid mixtures found within the mitochondrial inner membrane, using merocyanine (MC540) fluorescence. We broadly categorized lipid vesicles of equal mass as loosely packed, intermediate, and highly packed based on peak MC540 fluorescence intensity. CL had opposite effects on loosely versus highly packed vesicles. Exposure of loosely packed vesicles to increasing levels of CL dose-dependently increased membrane packing. In contrast, increasing amounts of CL in highly packed vesicles decreased the packing in a dose-dependent manner. In vesicles that were categorized as intermediate packing, CL had either no effect or decreased packing at select doses in a dose-independent manner. Altogether, the results aid in resolving some of the discrepant data by demonstrating that CL displays differential effects on membrane packing depending on the composition of the lipid environment. This has implications for mitochondrial protein activity in response to changing CL levels in microdomains of varying composition.

  11. 12 CFR 263.85 - Establishment of increased capital level for specific institutions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... temporary or final cease-and-desist order issued pursuant to section 8(b) or (c) of the FDIA (12 U.S.C. 1818(b) or (c)); (3) A condition for approval of an application or issuance of a notice of intent not to... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Establishment of increased capital level...

  12. 12 CFR 263.85 - Establishment of increased capital level for specific institutions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... temporary or final cease-and-desist order issued pursuant to section 8(b) or (c) of the FDIA (12 U.S.C. 1818(b) or (c)); (3) A condition for approval of an application or issuance of a notice of intent not to... 12 Banks and Banking 3 2011-01-01 2011-01-01 false Establishment of increased capital level...

  13. 12 CFR 263.85 - Establishment of increased capital level for specific institutions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...) A temporary or final cease-and-desist order issued pursuant to section 8(b) or (c) of the FDIA (12 U.S.C. 1818(b) or (c)); (3) A condition for approval of an application or issuance of a notice of... 12 Banks and Banking 4 2013-01-01 2013-01-01 false Establishment of increased capital level...

  14. Increased cancer cell proliferation in prostate cancer patients with high levels of serum folate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: A recent clinical trial revealed that folic acid supplementation is associated with an increased incidence of prostate cancer (1). The present study evaluates serum and prostate tissue folate levels in men with prostate cancer, compared to histologically normal prostate glands from can...

  15. Increased serum hepcidin levels in subjects with the metabolic syndrome: a population study.

    PubMed

    Martinelli, Nicola; Traglia, Michela; Campostrini, Natascia; Biino, Ginevra; Corbella, Michela; Sala, Cinzia; Busti, Fabiana; Masciullo, Corrado; Manna, Daniele; Previtali, Sara; Castagna, Annalisa; Pistis, Giorgio; Olivieri, Oliviero; Toniolo, Daniela; Camaschella, Clara; Girelli, Domenico

    2012-01-01

    The recent discovery of hepcidin, the key iron regulatory hormone, has changed our view of iron metabolism, which in turn is long known to be linked with insulin resistant states, including type 2 diabetes mellitus and the Metabolic Syndrome (MetS). Serum ferritin levels are often elevated in MetS (Dysmetabolic hyperferritinemia--DHF), and are sometimes associated with a true mild-to-moderate hepatic iron overload (dysmetabolic iron overload syndrome--DIOS). However, the pathophysiological link between iron and MetS remains unclear. This study was aimed to investigate, for the first time, the relationship between MetS and hepcidin at population level. We measured serum hepcidin levels by Mass Spectrometry in 1,391 subjects from the Val Borbera population, and evaluated their relationship with classical MetS features. Hepcidin levels increased significantly and linearly with increasing number of MetS features, paralleling the trend of serum ferritin. In multivariate models adjusted for relevant variables including age, C-Reactive Protein, and the HFE C282Y mutation, ferritin was the only significant independent predictor of hepcidin in males, while in females MetS was also independently associated with hepcidin. Overall, these data indicate that the fundamental iron regulatory feedback is preserved in MetS, i.e. that hepcidin tends to progressively increase in response to the increase of iron stores. Due to recently discovered pleiotropic effects of hepcidin, this may worsen insulin resistance and contribute to the cardiovascular complications of MetS.

  16. Increased Serum Hepcidin Levels in Subjects with the Metabolic Syndrome: A Population Study

    PubMed Central

    Martinelli, Nicola; Traglia, Michela; Campostrini, Natascia; Biino, Ginevra; Corbella, Michela; Sala, Cinzia; Busti, Fabiana; Masciullo, Corrado; Manna, Daniele; Previtali, Sara; Castagna, Annalisa; Pistis, Giorgio; Olivieri, Oliviero; Toniolo, Daniela; Camaschella, Clara; Girelli, Domenico

    2012-01-01

    The recent discovery of hepcidin, the key iron regulatory hormone, has changed our view of iron metabolism, which in turn is long known to be linked with insulin resistant states, including type 2 diabetes mellitus and the Metabolic Syndrome (MetS). Serum ferritin levels are often elevated in MetS (Dysmetabolic hyperferritinemia - DHF), and are sometimes associated with a true mild-to-moderate hepatic iron overload (dysmetabolic iron overload syndrome - DIOS). However, the pathophysiological link between iron and MetS remains unclear. This study was aimed to investigate, for the first time, the relationship between MetS and hepcidin at population level. We measured serum hepcidin levels by Mass Spectrometry in 1,391 subjects from the Val Borbera population, and evaluated their relationship with classical MetS features. Hepcidin levels increased significantly and linearly with increasing number of MetS features, paralleling the trend of serum ferritin. In multivariate models adjusted for relevant variables including age, C-Reactive Protein, and the HFE C282Y mutation, ferritin was the only significant independent predictor of hepcidin in males, while in females MetS was also independently associated with hepcidin. Overall, these data indicate that the fundamental iron regulatory feedback is preserved in MetS, i.e. that hepcidin tends to progressively increase in response to the increase of iron stores. Due to recently discovered pleiotropic effects of hepcidin, this may worsen insulin resistance and contribute to the cardiovascular complications of MetS. PMID:23144745

  17. Gallic acid induces HeLa cell death via increasing GSH depletion rather than ROS levels.

    PubMed

    Park, Woo Hyun

    2017-02-01

    Gallic acid (GA; 3,4,5-triphydroxyl-benzoic acid) is widely dispersed in various plants, fruits and foods and it shows various biological properties including anticancer effects. This study investigated the effects of GA on HeLa cervical cancer cells in relation to cell death, reactive oxygen species (ROS) and glutathione (GSH). GA dose-dependently inhibited the growth of HeLa cells and human umbilical vein endothelial cells (HUVEC) at 24 or 72 h. The susceptibility of HeLa cells to GA was higher than that of HUVEC. GA induced apoptosis in HeLa cells, which was accompanied by the loss of mitochondrial membrane potential (MMP; ∆ψm). GA increased ROS levels including O2•- in HeLa cells at 24 h and it also induced GSH depletion. N-acetyl cysteine (NAC) increased the growth inhibition of GA-treated HeLa cells and enhanced the death of these cells. NAC differently influenced ROS levels in GA-treated HeLa cells and significantly increased GSH depletion in these cells. L-buthionine sulfoximine (BSO) increased MMP (∆ψm) loss, ROS levels and GSH depletion in GA-treated HeLa cells. In conclusion, GA significantly inhibited the growth of HeLa cells. GA-induced HeLa cell death was tightly related to GSH depletion rather than ROS level changes.

  18. Delta(9)-tetrahydrocannabinol enhances an increase of plasma corticosterone levels induced by forced swim-stress.

    PubMed

    Sano, Kazunori; Koushi, Emi; Irie, Keiichi; Higuchi, Sei; Tsuchihashi, Ryota; Kinjo, Junei; Egashira, Nobuaki; Oishi, Ryozo; Uchida, Naoki; Nagai, Hiroshi; Nishimura, Ryoji; Tanaka, Hiroyuki; Morimoto, Satoshi; Mishima, Kenichi; Iwasaki, Katsunori; Fujiwara, Michihiro

    2009-12-01

    The present study was designed to determine the effect of delta(9)-tetrahydrocannabinol (THC) on susceptibility to stress. We reported that THC significantly prolonged the immobility time during the forced swim-stress. The selective cannabinoid CB(1) receptor antagonist O-2050 significantly reduced the enhancement of immobility by THC. We investigated the effect of THC on levels of stress hormone corticosterone under non-stress and forced swim-stress conditions. THC did not affect plasma corticosterone levels under non-stress conditions. However, THC, together with forced swim-stress, significantly increased plasma corticosterone levels. This effect was inhibited by O-2050. This evidence suggests that THC, under stressful conditions, enhances the susceptibility of the hypothalamus-pituitary-adrenal-axis to stress via the CB(1) receptor, thereby increasing the risk of depression.

  19. Large enhancement in thermoelectric efficiency of quantum dot junctions due to increase of level degeneracy

    NASA Astrophysics Data System (ADS)

    Kuo, David M. T.; Chen, Chih-Chieh; Chang, Yia-Chung

    2017-02-01

    It is theoretically demonstrated that the figure of merit (Z T ) of quantum dot (QD) junctions can be significantly enhanced when the degree of degeneracy of the energy levels involved in electron transport is increased. The theory is based on the the Green-function approach in the Coulomb blockade regime by including all correlation functions resulting from electron-electron interactions associated with the degenerate levels (L ). We found that electrical conductance (Ge) as well as electron thermal conductance (κe) are highly dependent on the level degeneracy (L ), whereas the Seebeck coefficient (S ) is not. Therefore, the large enhancement of Z T is mainly attributed to the increase of Ge when the phonon thermal conductance (κp h) dominates the heat transport of the QD junction system. In the serially coupled double-QD case, we also obtain a large enhancement of Z T arising from higher L . Unlike Ge and κe, S is found almost independent on electron interdot hopping strength.

  20. Global increasing of mean sea level and erroneous treatment of a role of thermal factors

    NASA Astrophysics Data System (ADS)

    Barkin, Yu. V.

    2009-04-01

    Satellite methods of studies of the ocean surface - methods of altimetry - have been obtained intensive development in the last decades (since 1993). However, altimetry studies with the help of special satellites such as TOPEX-Poseidon not only have not cleared up understanding of the phenomenon of increase of sea level (SLR), but have even more confused and without that a complex question on the reasons of increase of sea level. Appeared, that classical determinations of average velocity of increase of sea level on coastal observations (1.4-1.7 mm / yr) approximately for 0.8-1.0 mm / yr it is less, rather than by modern satellite determinations of satellites TOPEX - Poseidon etc. (2.5 - 2.8 mm / yr). On the basis of the data of altimetry observations of TOPEX-Poseidon and Jason for the period 1993-2003 for geocentric velocity of increase of sea level (of global ocean) the value 2.8+/-0.4 mm / yr [1] has been obtained. In the given report the full answer is actually is given to a question put by leading experts on research of the sea level: "The TOPEX/Poseidon and Jason satellite altimeter missions provided a 12 year record of sea level change, which show increase of global mean sea level of 2.8+/-0.4 mm/yr, with considerable geographic variation. An important question for climate studies is to determine the cause of this change - specifically how much of the change is due to steric (heating) versus eustatic (runoff, melting ice, etc.) contribution?" [1]. There is, a big value of average velocity of increase of the sea level on the satellite data, it is possible to explain only by kinematical effect in data of observations. The motion of the satellite "is concerned" to the centre of mass of our planet, and its position is determined by a geocentric radius - vector. Therefore northern drift of the centre of mass in the Earth body [2] as though results in reduction of distances from the satellite up to the sea surface in the southern hemisphere and to their reduction

  1. Increased human AP endonuclease 1 level confers protection against the paternal age effect in mice

    PubMed Central

    Sanchez, Jamila R.; Reddick, Traci L.; Perez, Marissa; Centonze, Victoria E.; Mitra, Sankar; Izumi, Tadahide; McMahan, C. Alex; Walter, Christi A.

    2015-01-01

    Increased paternal age is associated with a greater risk of producing children with genetic disorders originating from de novo germline mutations. Mice mimic the human condition by displaying an age-associated increase in spontaneous mutant frequency in spermatogenic cells. The observed increase in mutant frequency appears to be associated with a decrease in the DNA repair protein, AP endonuclease1 (APEX1) and Apex1 heterozygous mice display an accelerated paternal age effect as young adults. In this study, we directly tested if APEX1 over-expression in cell lines and transgenic mice could prevent increases in mutagenesis. Cell lines with ectopic expression of APEX1 had increased APEX1 activity and lower spontaneous and induced mutations in the lacI reporter gene relative to the control. Spermatogenic cells obtained from mice transgenic for human APEX1 displayed increased APEX1 activity, were protected from the age-dependent increase in spontaneous germline mutagenesis, and exhibited increased apoptosis in the spermatogonial cell population. These results directly indicate that increases in APEX1 level confer protection against the murine paternal age effect, thus highlighting the role of APEX1 in preserving reproductive health with increasing age and in protection against genotoxin-induced mutagenesis in somatic cells. PMID:26201249

  2. Atherogenic diet increases cholesteryl ester transfer protein messenger RNA levels in rabbit liver.

    PubMed

    Quinet, E M; Agellon, L B; Kroon, P A; Marcel, Y L; Lee, Y C; Whitlock, M E; Tall, A R

    1990-02-01

    Cholesteryl ester transfer activity is increased in plasma of cholesterol-fed rabbits. To investigate the mechanisms leading to changes in activity, we measured cholesteryl ester transfer protein (CETP) mass by RIA and CETP mRNA abundance by Northern and slot blot analysis using a human CETP cDNA probe in control (n = 8) and cholesterol-fed rabbits (n = 10). Cholesterol feeding (chow plus 0.5% cholesterol, 10% corn oil) for 30 d increased CETP mass in plasma 3.2-fold in the cholesterol-fed rabbits (12.45 +/- 0.82 micrograms/ml) compared with controls (3.86 +/- 0.38 micrograms/ml). In the hypercholesterolemic rabbit, liver CETP mRNA levels were increased 2.8 times control mRNA levels. Actin, apo E, lecithin-cholesterol acyltransferase, and albumin mRNA abundances were unchanged. In contrast to the widespread tissue distribution in humans, CETP mRNA was not detected in extrahepatic tissues of either control or cholesterol-fed animals. Using a sensitive RNase protection assay, the increase in liver CETP mRNA was detectable within 3 d of beginning the high cholesterol diet. Thus, in response to the atherogenic diet there is an early increase in liver CETP mRNA, probably causing increased CETP synthesis and secretion, and increased plasma CETP. The results indicate that the CETP gene may be regulated by diet-induced changes in lipid metabolism.

  3. Increased levels of ambient fungal spores in Taiwan are associated with dust events from China

    NASA Astrophysics Data System (ADS)

    Wu, Pei-Chih; Tsai, Jui-Chen; Li, Fang-Chun; Lung, Shih-Chun; Su, Huey-Jen

    2004-09-01

    Fungi are ubiquitous in nature and their spores are often dispersed into the atmosphere through turbulent airstreams. As yellow sandstorm blown from deserts in China had affected the ambient air quality with increasing levels of ambient particulates, often including significant amounts of biologically active particles has therefore become imperative for concerns of their health implications. Our study was aimed to examine the effects of yellow sandstorm events on the fungal composition and concentrations in ambient air. Atmospheric fungal spores were continuously collected using Burkard Volumetric Spore Trap. Samples collected between December 2000 and April 2001 were selected for priority analysis from days when the yellow sandstorms were reported to affect Taiwan according to the Central Weather Bureau in Taiwan. The composition of dominant spores such as Basidiospore, Penicillium/Aspergillus, Nigrospora, Arthrinium, Curvularia, Rusts, Stemphylium, Cercospora, Pithomyces, and unidentified fungi were significantly higher than those of background days. The increase of Basidiospore, Penicillium/Aspergillus, Nigrospora, and those unidentified fungi seems to be significantly associated with the increase of ambient particulate levels with regression coefficients ranging from 0.887 to 31.98. Our study has identified increasing ambient concentrations during sandstorm episodes are observed for some major fungi, Basidiospore, Penicillium, Aspergillus, and those unidentified fungi and the trends of the increase seems to associate with ambient particulate levels. Further efforts to clarify the relationship between those high fungal spore exposures and clinical adverse health effects are suggested in the future. In addition, effects of climatic factors and other particulate levels on the variation of ambient fungal spore levels are also desired in further study. Additional monitoring of ambient fungal spores in the first line of west coastline is hoped to assist in

  4. Remifentanil Prevents Increases of Blood Glucose and Lactate Levels during Cardiopulmonary Bypass in Pediatric Cardiac Surgery

    PubMed Central

    Chaki, Tomohiro; Nawa, Yuko; Tamashiro, Keishi; Mizuno, Eri; Hirata, Naoyuki; Yamakage, Michiaki

    2017-01-01

    Introduction: Cardiopulmonary bypass (CPB) can cause stress response that increases levels of cytokine and catecholamine in plasma, resulting in hyperglycemia. In adults, it has been demonstrated that remifentanil infusion during CPB could prevent increases of cytokine, catecholamine, and blood glucose levels, but such effects of remifentanil in children have not been elucidated. Aim: In this study, we investigated the preventive effects of remifentanil on blood glucose and lactate levels during CPB in children. Materials and Methods: This retrospective study included children who underwent ventricular septal defect or atrial septal defect closure. Data for patients who did not receive, during CPB period, remifentanil infusion (non-Remi group) and patients who received remifentanil infusion at 0.5 μg/kg/min (Remi group) during CPB were used for analysis. Primary outcomes were lactate and blood glucose levels just before and after CPB. Data are presented as medians and interquartile ranges. Data were analyzed by the Mann–Whitney U-test and Chi-square test. A P < 0.05 was considered statistically significant. Results: During CPB, 13 and 11 patients were allocated into Remi and non-Remi groups, respectively. Pre-CPB lactate and blood glucose levels were not significantly different between the two groups, but post-CPB lactate and blood glucose levels in the Remi group were significantly lower than that in the non-Remi group. Conclusion: 0.5 μg/kg/min remifentanil infusion during CPB suppresses the increases of blood glucose and lactate levels in children. PMID:28074792

  5. Increased biogenic catecholamine and metabolite levels in two patients with malignant catatonia.

    PubMed

    Nisijima, Koichi

    2013-01-01

    The pathophysiology of malignant catatonia, a rare life-threatening psychiatric syndrome, has not yet been elucidated. This paper reports on two patients with malignant catatonia who showed elevated urinary or plasma catecholamine levels. Patient 1 had high catecholamine and metabolite levels in a 24-hour urine sample, and patient 2 had elevated plasma catecholamine levels. These findings indicate the presence of peripheral sympathetic nervous system hyperactivity in malignant catatonia. Symptoms of autonomic dysfunction, including tachycardia, labile blood pressure, and diaphoresis, are typical features of malignant catatonia and may be related to the increased levels of biogenic amines in these cases. Although the findings in the present study cannot entirely explain the pathophysiology of malignant catatonia, they do indicate that hyperactivity of the sympathetic nervous system may be involved in the pathology of this condition.

  6. Cyclic AMP agonist inhibition increases at low levels of histamine release from human basophils

    SciTech Connect

    Tung, R.S.; Lichtenstein, L.M.

    1981-09-01

    The relationship between the intensity of the signal for antigen-induced immunoglobulin E-mediated histamine release from human basophils and the concentration of agonist needed to inhibit release has been determined. The agonists, prostaglandin E1, dimaprit, fenoterol, isobutylmethylxanthine and dibutyryl cyclic AMP, all act by increasing the cyclic AMP level. Each agonist was 10- to 1000-fold more potent (relative ID50) at low levels of histamine release (5-10% of total histamine) than at high levels (50-80%). Thus, the inhibitory potential of a drug is a function of the concentration of antigen used to initiate the response. Our results are now more in accord with the inhibitory profile of these drugs in human lung tissue. It is suggested that in vivo release is likely to be low and that this is the level at which to evaluate drugs in vitro.

  7. Effects of alprazolam on increases in hormonal and anxiety levels induced by meta-chlorophenylpiperazine.

    PubMed

    Sevy, S; Brown, S L; Wetzler, S; Kotler, M; Molcho, A; Plutchik, R; van Praag, H M

    1994-09-01

    The effects of alprazolam, a triazolobenzodiazepine, on hormonal and behavioral responses induced by meta-chlorophenylpiperazine (MCPP), a serotonin receptor agonist, were investigated in 10 healthy men. Alprazolam (0.5 mg) or placebo was given 1 hour before MCPP (0.5 mg/kg) or placebo. Cortisol, prolactin, and growth hormone (GH) release, MCPP and alprazolam plasma levels, anxiety level, and panic symptoms were measured over 210 minutes. MCPP was found to increase cortisol, prolactin, GH, and anxiety levels. Alprazolam decreased cortisol and GH levels but had no effect on prolactin. When used in combination with MCPP, alprazolam blunted MCPP-induced cortisol and GH release, and it blocked the anxiogenic effects of MCPP.

  8. [Effect of the increasing levels of soil radioactive pollution on the biochemical composition of plants].

    PubMed

    Gromova, V S; Pchelenok, O A; Kozlova, N M

    2012-01-01

    The study was undertaken to study a relationship between the changes of some parameters of the biochemical and mineral composition of different plants, such as rape, pods, and lentil, and the levels of soil radiation pollution, by using the conventional methods. Radioactive pollution of dark-grey forest soils was found to cause a change in the biochemical composition of plant seeds even at the level of cesium 137 (137Cs) within the present temporary permissible levels (TPL) (600 Bq/kg): there were elevated concentrations of salts of potassium, phosphorus, ammonia nitrogen, catechols, sucrose, and some amino acids. With the radioactive cesium level exceeding the TPL, biochemical changes in the seeds depended on the species of the plants: in the rape seeds, the additional formation of sucrose and amino acids continued, but less intensively than with its lower radiation; the pod beans were significantly positively correlated with the increasing amounts of catechols.

  9. Overexpression of an ABA biosynthesis gene using a stress inducible promoter enhances drought resistance in petunia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plants respond to drought stress by closing their stomata and reducing transpirational water loss. The plant hormone abscisic acid (ABA) regulates growth and stomatal closure particularly when the plant is under environmental stresses. One of the key enzymes in the ABA biosynthesis of higher plants ...

  10. From the Classroom to the Family Room: Using ABA for Best Behavior

    ERIC Educational Resources Information Center

    Smith, Dawn

    2010-01-01

    When it comes to supporting individuals with disabilities including Autism Spectrum Disorder (ASD), Applied Behavior Analysis (ABA) can be an invaluable tool in understanding and changing behavior. More than a technique or method, ABA is a disciplined approach rooted in science to teach specific skills and then reinforce them so individuals can…

  11. None of the As in ABA Stand for Autism: Dispelling the Myths

    ERIC Educational Resources Information Center

    Dillenburger, Karola; Keenan, Mickey

    2009-01-01

    Interventions that are based on scientific principles of applied behaviour analysis (ABA) are recognised as effective treatments for children with autism spectrum disorder (ASD) by many governments and professionals (Office of the Surgeon General, 2000; Ontario IBI Initiative, 2002). However, many still view ABA as one of many treatments for…

  12. Brief Report: Comparative ABA and DIR Trials in Twin Brothers with Autism

    ERIC Educational Resources Information Center

    Hilton, Jane C.; Seal, Brenda C.

    2007-01-01

    Trial interventions in DIR and ABA with twin brothers with autism were offered to help the parents choose one of the programs for their sons. Pre- and post-test scores on the Communication and Symbolic Behavior Scales (CSBS) revealed a slight gain in the composite score of the ABA child and a slight loss in the score of the DIR child. Contrasted…

  13. Surface L-type Ca2+ channel expression levels are increased in aged hippocampus

    PubMed Central

    Núñez-Santana, Félix Luis; Oh, Myongsoo Matthew; Antion, Marcia Diana; Lee, Amy; Hell, Johannes Wilhelm; Disterhoft, John Francis

    2014-01-01

    Age-related increase in L-type Ca2+ channel (LTCC) expression in hippocampal pyramidal neurons has been hypothesized to underlie the increased Ca2+ influx and subsequent reduced intrinsic neuronal excitability of these neurons that lead to age-related cognitive deficits. Here, using specific antibodies against Cav1.2 and Cav1.3 subunits of LTCCs, we systematically re-examined the expression of these proteins in the hippocampus from young (3 to 4 month old) and aged (30 to 32 month old) F344xBN rats. Western blot analysis of the total expression levels revealed significant reductions in both Cav1.2 and Cav1.3 subunits from all three major hippocampal regions of aged rats. Despite the decreases in total expression levels, surface biotinylation experiments revealed significantly higher proportion of expression on the plasma membrane of Cav1.2 in the CA1 and CA3 regions and of Cav1.3 in the CA3 region from aged rats. Furthermore, the surface biotinylation results were supported by immunohistochemical analysis that revealed significant increases in Cav1.2 immunoreactivity in the CA1 and CA3 regions of aged hippocampal pyramidal neurons. In addition, we found a significant increase in the level of phosphorylated Cav1.2 on the plasma membrane in the dentate gyrus of aged rats. Taken together, our present findings strongly suggest that age-related cognitive deficits cannot be attributed to a global change in L-type channel expression nor to the level of phosphorylation of Cav1.2 on the plasma membrane of hippocampal neurons. Rather, increased expression and density of LTCCs on the plasma membrane may underlie the age-related increase in L-type Ca2+ channel activity in CA1 pyramidal neurons. PMID:24033980

  14. Inositol Depletion Induced by Acute Treatment of the Bipolar Disorder Drug Valproate Increases Levels of Phytosphingosine.

    PubMed

    Jadhav, Shyamalagauri; Russo, Sarah; Cowart, L Ashley; Greenberg, Miriam L

    2017-03-24

    Bipolar disorder (BD) is a severe psychiatric illness affecting ∼1% of the world population. Valproate (VPA) and lithium, widely used for the treatment of BD, are not universally effective. These drugs have been shown to cause inositol depletion, but translating this observation to a specific therapeutic mechanism has been difficult, hampering the development of more effective therapies. We have shown previously in yeast that chronic VPA treatment induces the unfolded protein response due to increasing ceramide levels. To gain insight into the mechanisms activated during acute VPA treatment, we performed a genome-wide expression study in yeast treated with VPA for 30 min. We observed increased mRNA and protein levels of RSB1, which encodes an exporter of long chain bases dihydrosphingosine (DHS) and phytosphingosine (PHS), and further saw that VPA increased sensitivity of an rsb1Δ mutant to PHS, suggesting that VPA increases long chain base levels. Consistent with this, PHS levels were elevated in wild type and, to a greater extent, in rsb1Δ cells. Expression of ORM genes (negative regulators of PHS synthesis) and of fatty acid elongase genes FEN1 and SUR4 were decreased, and expression of YOR1 (exporter of PHS-1P) and DPL1 (lyase that degrades DHS-1P and PHS-1P) was increased. These effects were more pronounced in medium lacking inositol, and were mirrored by inositol starvation of an ino1Δ mutant. These findings provide a metabolic explanation as to how VPA-mediated inositol depletion causes increased synthesis of PHS and further support the therapeutic relevance of inositol depletion as a bipolar disorder treatment.

  15. Ceramide synthases and ceramide levels are increased in breast cancer tissue.

    PubMed

    Schiffmann, Susanne; Sandner, Jessica; Birod, Kerstin; Wobst, Ivonne; Angioni, Carlo; Ruckhäberle, Eugen; Kaufmann, Manfred; Ackermann, Hanns; Lötsch, Jörn; Schmidt, Helmut; Geisslinger, Gerd; Grösch, Sabine

    2009-05-01

    Several in vitro studies have correlated dysfunction of the sphingolipid-signaling pathway with promotion of tumor cell growth as well as progression and resistance of tumors to chemotherapeutic agents. As ceramides (Cer) constitute the structural backbones of all sphingolipids, we investigated the endogenous ceramide levels in 43 malignant breast tumors and 21 benign breast biopsies and compared them with those of normal tissues using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The total ceramide levels in malignant tumor tissue samples were statistically significantly elevated when compared with normal tissue samples. Upregulation of the total ceramide level averaged 12-fold and 4-fold higher than normal tissue samples, for malignant tumors and benign tissues, respectively. Specifically, the levels of C(16:0)-Cer, C(24:1)-Cer and C(24:0)-Cer were significantly raised in malignant tumors as compared with benign and normal tissue. The augmentation of the various ceramides could be assigned to an increase of the messenger RNA levels of ceramide synthases (CerS) LASS2 (longevity assurance), LASS4 and LASS6. Notably, elevated levels of C(16:0)-Cer were associated with a positive lymph node status, indicating a metastatic potential for this ceramide. Moreover, the levels of C(18:0)-Cer and C(20:0)-Cer were significantly higher in estrogen receptor (ER) positive tumor tissues as compared with ER negative tumor tissues. In conclusion, progression in breast cancer is associated with increased ceramide levels due to an upregulation of specific LASS genes.

  16. Major Abdominal Surgery Increases Plasma Levels of Vascular Endothelial Growth Factor

    PubMed Central

    Belizon, Avraham; Balik, Emre; Feingold, Daniel L.; Bessler, Marc; Arnell, Tracey D.; Forde, Kenneth A.; Horst, Patrick K.; Jain, Suvinit; Cekic, Vesna; Kirman, Irena; Whelan, Richard L.

    2006-01-01

    Introduction: Vascular endothelial growth factor (VEGF) is a potent inducer of angiogenesis that is necessary for wound healing and also promotes tumor growth. It is anticipated that plasma levels would increase after major surgery and that such elevations may facilitate tumor growth. This study's purpose was to determine plasma VEGF levels before and early after major open and minimally invasive abdominal surgery. Methods: Colorectal resection for cancer (n = 139) or benign pathology (n = 48) and gastric bypass for morbid obesity (n = 40) were assessed. Similar numbers of open and laparoscopic patients were studied for each indication. Plasma samples were obtained preoperatively and on postoperative days (POD) 1 and 3. VEGF levels were determined via ELISA. The following statistical methods were used: Fisher exact test, unmatched Student t test, Wilcoxon's matched pairs test, and the Mann Whitney U Test with P < 0.05 considered significant. Results: The mean preoperative VEGF level of the cancer patients was significantly higher than baseline level of benign colon patients. Regardless of indication or surgical method, on POD3, significantly elevated mean VEGF levels were noted for each subgroup. In addition, on POD1, open surgery patients for all 3 indications had significantly elevated VEGF levels; no POD1 differences were noted for the closed surgery patients. At each postoperative time point for each procedure and indication, the open group's VEGF levels were significantly higher than that of the matching laparoscopic group. VEGF elevations correlated with incision length for each indication. Conclusion: As a group colon cancer patients prior to surgery have significantly higher mean VEGF levels than patients without tumors. Also, both open and closed colorectal resection and gastric bypass are associated with significantly elevated plasma VEGF levels early after surgery. This elevation is significantly greater and occurs earlier in open surgery patients. The

  17. Increased plasma neopterin and hs-CRP levels in patients with endemic fluorosis.

    PubMed

    Varol, Ercan; Aksoy, Fatih; Icli, Atilla; Arslan, Akif; Yuksel, Ozlem; Ersoy, I Hakki; Varol, Simge; Dogan, Abdullah

    2012-11-01

    Although fluoride induced inflammatory reactions have been shown in animals and in vitro humans, there are few studies about fluoride induced inflammatory reactions in human beings at clinical setting. We aimed to measure the plasma neopterin, a marker of activation of the monocyte/macrophage system, and high sensitivity C-reactive protein (hs-CRP) levels in patients with endemic fluorosis to investigate the possible role of inflammatory processes (monocyte/macrophage activity) in the underlying pathophysiology of fluoride toxicity at clinical level. Plasma neopterin and hs-CRP levels were determined in endemic fluorosis patients and control subjects. Plasma neopterin levels were significantly higher among patients with endemic fluorosis when compared with control group (2.40 ± 0.66 vs. 1.63 ± 0.27 ng/mL respectively; p < 0.001) and plasma hs-CRP levels were also significantly higher among patients with endemic fluorosis when compared with control group (2.41 ± 1.23 vs. 1.93 ± 0.64 mg/L respectively; p < 0.001). Plasma neopterin levels were positively correlated with urine fluoride levels (r = 0.67, p < 0.001) and serum hs-CRP levels were positively correlated with urine fluoride levels (r = 0.36, p < 0.001). We have found that plasma neopterin and hs-CRP levels are increased in patients with endemic fluorosis. We have concluded that inflammation play an important role in the pathophysiology of fluoride toxicity in patients with endemic fluorosis.

  18. Low oxygen level increases proliferation and metabolic changes in bovine granulosa cells.

    PubMed

    Shiratsuki, Shogo; Hara, Tomotaka; Munakata, Yasuhisa; Shirasuna, Koumei; Kuwayama, Takehito; Iwata, Hisataka

    2016-12-05

    The present study addresses molecular backgrounds underlying low oxygen induced metabolic changes and 1.2-fold change in bovine granulosa cell (GCs) proliferation. RNA-seq revealed that low oxygen (5%) upregulated genes associated with HIF-1 and glycolysis and downregulated genes associated with mitochondrial respiration than that in high oxygen level (21%). Low oxygen level induced high glycolytic activity and low mitochondrial function and biogenesis. Low oxygen level enhanced GC proliferation with high expression levels of HIF-1, VEGF, AKT, mTOR, and S6RP, whereas addition of anti-VEGF antibody decreased cellular proliferation with low phosphorylated AKT and mTOR expression levels. Low oxygen level reduced SIRT1, whereas activation of SIRT1 by resveratrol increased mitochondrial replication and decreased cellular proliferation with reduction of phosphorylated mTOR. These results suggest that low oxygen level stimulates the HIF1-VEGF-AKT-mTOR pathway and up-regulates glycolysis, which contributes to GC proliferation, and downregulation of SIRT1 contributes to hypoxia-associated reduction of mitochondria and cellular proliferation.

  19. Methodology for Prototyping Increased Levels of Automation for Spacecraft Rendezvous Functions

    NASA Technical Reports Server (NTRS)

    Hart, Jeremy J.; Valasek, John

    2007-01-01

    The Crew Exploration Vehicle necessitates higher levels of automation than previous NASA vehicles, due to program requirements for automation, including Automated Rendezvous and Docking. Studies of spacecraft development often point to the locus of decision-making authority between humans and computers (i.e. automation) as a prime driver for cost, safety, and mission success. Therefore, a critical component in the Crew Exploration Vehicle development is the determination of the correct level of automation. To identify the appropriate levels of automation and autonomy to design into a human space flight vehicle, NASA has created the Function-specific Level of Autonomy and Automation Tool. This paper develops a methodology for prototyping increased levels of automation for spacecraft rendezvous functions. This methodology is used to evaluate the accuracy of the Function-specific Level of Autonomy and Automation Tool specified levels of automation, via prototyping. Spacecraft rendezvous planning tasks are selected and then prototyped in Matlab using Fuzzy Logic techniques and existing Space Shuttle rendezvous trajectory algorithms.

  20. Increased Cytokine and Nitric Oxide Levels in Serum of Dogs Experimentally Infected with Rangelia vitalii

    PubMed Central

    Da Silva, Aleksandro S.; Paim, Carlos Breno V.; França, Raqueli T.; Costa, Márcio M.; Duarte, Marta M. M. F.; Sangoi, Manuela B.; Moresco, Rafael N.; Monteiro, Silvia G.; Lopes, Sonia Terezinha A.

    2013-01-01

    This study aimed to measure the levels of interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), interleukin 1 (IL-1), interleukin 6 (IL-6), and nitrite/nitrate (NOx) in serum of dogs experimentally infected with Rangelia vitalii. Twelve female mongrel dogs were divided into 2 groups; group A (uninfected controls) composed by healthy dogs (n=5) and group B consisting of dogs inoculated with R. vitalii (n=7). Animals were monitored by blood smear examinations, which showed intraerythrocytic forms of the parasite on day 5 post-infection (PI). Blood samples were collected through the jugular vein on days 0, 10, and 20 PI to determine the serum levels of IFN-γ, TNF-α, IL-1, IL-6, and NOx. Cytokines were assessed by ELISA quantitative sandwich technique, and NOx was measured by the modified Griess method. Cytokine levels (IFN-γ, TNF-α, IL-1, and IL-6) were increased (P<0.01) in serum of infected animals. Serum levels of NOx were also increased on days 10 PI (P<0.01) and 20 PI (P<0.05) in infected animals. Therefore, the infection with R. vitalii causes an increase in proinflammatory cytokines and nitric oxide content. These alterations may be associated with host immune protection against the parasite. PMID:23467990

  1. Mothers Do Not Show Increased Offspring Avoidance and Elevated Corticosterone Levels during Weaning Conflict in Rats

    PubMed Central

    Cox, Charlotte; Hager, Reinmar

    2016-01-01

    Parent-offspring conflict is predicted to occur because offspring will demand more parental investment than is optimal for the parent, and is said to be strongest during weaning when parents reduce nursing while offspring continue to demand parental care. While weaning conflict has been shown to be stressful in offspring, little is known about the effects of weaning conflict on mothers. We hypothesized that during weaning mothers have higher levels of stress hormone (corticosterone) compared to early lactation because of increased offspring demand. Further, we predicted that if mothers are given the option to avoid offspring solicitation they would do so and show lower corticosterone levels. We tested our hypotheses in an experimental population of rats in which one group of females was given the opportunity to avoid offspring solicitation. We measured faecal corticosterone metabolite levels using a non-invasive approach, and maternal and offspring behaviours during weaning. In contrast to our predictions, we detected lower levels of corticosterone metabolites during weaning than before, irrespective of cage type. Further, during weaning mothers did not show increased offspring avoidance behaviour although offspring solicitation increased significantly. Our results therefore cast doubt on the generally accepted notion of weaning conflict as a stressful period for mothers characterized by overt offspring solicitation. PMID:27662366

  2. Sodium Chloride IncreasesLevels by Suppressing Aβ Clearance in Cultured Cells.

    PubMed

    Cheng, Xiao-Juan; Gao, Yuan; Zhao, Yu-Wu; Cheng, Xiao-Dong

    2015-01-01

    Recent studies suggest that high-salt diet is associated with cognitive decline in human and mouse. The fact that genetic factors account for less than 50% cases of sporadic Alzheimer's disease (AD) highlights the important contribution of environmental factors, such as high-salt diet, in AD pathogenesis. However, whether and how high-salt diet fits the "amyloid cascade" hypothesis remains unexplored. Here, we show sodium chloride (NaCl) could increaselevels in the medium of HEK293 cells overexpressing amyloid precursor protein (APP) or C99 fragment. NaCl treatment dose not affect APP level, gamma secretase level or activity. Instead, NaCl treatment suppresses the capacity of cells to clear Aβ and reduces Apolipoprotein E (ApoE) level. Finally, NaCl treated THP-1 or BV2 cells are inefficient in clearing Aβ when co-cultured with rat primary neurons. Our study suggests that high-salt diet may increase AD risk by directly modulating Aβ levels.

  3. Stomatal numbers are sensitive to increases in CO2 from pre-industrial levels

    NASA Astrophysics Data System (ADS)

    Woodward, F. I.

    1987-06-01

    Recent measurements of atmospheric CO2 levels in ice cores1 have shown that global CO2 has increased by about 60 µmol mol-1 over the past 200 years. Evidence for the response of plants in the field to this change in CO2 levels is here presented in the form of a significant change in stomatal density-an anatomical response of considerable ecophysiological importance. A 40% decrease in density of stomata was observed in herbarium specimens of leaves of eight temperate arboreal species collected over the last 200 years. This decline was confirmed for some of the species observed as herbarium specimens by experiments under controlled environmental conditions. In these an increase in the mole fraction of CO2 from 280 μmol mol-1 to the current ambient level of 340 µmol mol-1 was found to cause a decrease in stomatal density of 67%. Experiments have shown that the combination of this previously unreported response of stomatal density to the level of CO2, with the known responses of stomatal aperture2, cause water use efficiency to be much lower than expected at low levels of CO2 and over a wide range of humidities.

  4. Increase in Levels of BDNF is Associated with Inflammation and Oxidative Stress during Cardiopulmonary Bypass

    PubMed Central

    Amoureux, Sébastien; Sicard, Pierre; Korandji, Claudia; Borey, Angélique; Benkhadra, Salima; Sequeira-Le Grand, Anabelle; Vergely, Catherine; Girard, Claude; Rochette, Luc

    2008-01-01

    Cardiopulmonary Bypass (CPB) is thought to generate reactive oxygen species associated with a systemic inflammation and neurotrophins seem to be involved in cardiovascular inflammatory reactions. The aim of this study was to determine the impact of CPB on plasma neurotrophins levels and to appreciate the links existing between inflammation, oxidative stress and neurotrophins. Blood samples were taken from 27 patients undergoing cardiac surgery: before CPB, during ischemia and at reperfusion under CPB. Oxidative stress was evaluated using an Electron Spin Resonance technique by superoxide detection, and antioxidant defences by measurement of Endogenous Peroxidase Activity (EPA). The evolution of two neurotrophins: Brain Derived Neurotrophic Factor (BDNF) and Nerve Growth Factor (NGF) was assessed with an ELISA method. An inflammatory index was determined by a multiplex flow cytometry method. The inflammatory index showed that MCP-1, P-selectin, t-PA and interleukins 6, 8 and 10 levels increased during CPB (p<0.05). Superoxide production and EPA were higher during ischemia and reperfusion than before CPB (p<0.05). BDNF plasma levels were higher at reperfusion (p<0.05). NGF levels did not change. Our study shows an increase of BDNF levels, associated with an inflammatory phenomenon and a redox modification, in the plasma of patients undergoing cardiac surgery under CPB. The role played by this neurotrophin in this complex situation still needs to be elucidated, in particular its cellular origin. It is also necessary to understand whether BDNF has a beneficial or deleterious effect during CPB. PMID:23675091

  5. Oxidized low density lipoprotein increases RANKL level in human vascular cells. Involvement of oxidative stress

    SciTech Connect

    Mazière, Cécile; Salle, Valéry; Gomila, Cathy; Mazière, Jean-Claude

    2013-10-18

    Highlights: •Oxidized LDL enhances RANKL level in human smooth muscle cells. •The effect of OxLDL is mediated by the transcription factor NFAT. •UVA, H{sub 2}O{sub 2} and buthionine sulfoximine also increase RANKL level. •All these effects are observed in human fibroblasts and endothelial cells. -- Abstract: Receptor Activator of NFκB Ligand (RANKL) and its decoy receptor osteoprotegerin (OPG) have been shown to play a role not only in bone remodeling but also in inflammation, arterial calcification and atherosclerotic plaque rupture. In human smooth muscle cells, Cu{sup 2+}-oxidized LDL (CuLDL) 10–50 μg/ml increased reactive oxygen species (ROS) and RANKL level in a dose-dependent manner, whereas OPG level was not affected. The lipid extract of CuLDL reproduced the effects of the whole particle. Vivit, an inhibitor of the transcription factor NFAT, reduced the CuLDL-induced increase in RANKL, whereas PKA and NFκB inhibitors were ineffective. LDL oxidized by myeloperoxidase (MPO-LDL), or other pro-oxidant conditions such as ultraviolet A (UVA) irradiation, incubation with H{sub 2}O{sub 2} or with buthionine sulfoximine (BSO), an inhibitor of glutathione synthesis{sub ,} also induced an oxidative stress and enhanced RANKL level. The increase in RANKL in pro-oxidant conditions was also observed in fibroblasts and endothelial cells. Since RANKL is involved in myocardial inflammation, vascular calcification and plaque rupture, this study highlights a new mechanism whereby OxLDL might, by generation of an oxidative stress, exert a deleterious effect on different cell types of the arterial wall.

  6. Increasing Level of Leisure Physical Activity Could Reduce the Risk of Hip Fracture in Older Women

    PubMed Central

    Rong, Ke; Liu, Xiao-yu; Wu, Xu-hua; Li, Xiao-liu; Xia, Qing-quan; Chen, Jiong; Yin, Xiao-fan

    2016-01-01

    Abstract We carried out the study to investigate and quantitatively assess the potential association between current level of physical activity and the risk of osteoporosis hip fracture in older women. Relevant publications before October 2015 were identified using the PubMed and Ovid searching tools. A dose–response meta-analysis was carried out to combine and analysis results. Fourteen prospective studies were included in the meta-analysis. A general analysis of 9 studies showed a significant inverse relationship between increasing level of physical activity and risk of hip fracture in older women [relative risk (RR) = 0.93, 95% confidence interval (95% CI): 0.91–0.96]. The result of a sensitivity analysis was consistent with the general analysis (RR = 0.94, 95% CI: 0.93–0.96). The association between increasing level of physical activity and risk of wrist fracture was not statistically significant in a general analysis of three studies (RR = 1.004, 95% CI: 0.98–1.03). A potential direct association between increasing level of physical activity and risk of wrist fracture was observed after removing 1 study with the greatest weight (RR = 1.01, 95% CI: 1.00–1.03). No significant publication bias was observed in our analysis. Our results show that increasing level of physical activity within an appropriate range may reduce the risk of hip fracture but not the risk of wrist fracture in older women. PMID:26986111

  7. Road transportation stress promptly increases bovine peripheral blood absolute NK cell counts and cortisol levels.

    PubMed

    Ishizaki, Hiroshi; Kariya, Yoshihiro

    2010-06-01

    Livestock transportation effects on the number of circulating leukocytes have been reported. However, data related specifically to the relation between acute stress levels during transport and leukocyte differentiation, including lymphocyte subsets, are lacking. This study was undertaken to evaluate the distribution of peripheral blood leukocyte differential counts, CD25+ lymphocytes and NK cells in calves subjected to truck transportation on different road types. Healthy Japanese Black calves were divided into three treatments: 1) those moved around in a mountainous area (Group M); 2) those moved around on flatland (Group F); and 3) those that were not transported (control). The plasma cortisol levels in Group M increased during transport. The increase was significantly higher at the end of transport than in the controls (P<0.05); a slight increase was noted in Group F. Total leukocytes and the neutrophil to lymphocyte ratio in Group M were elevated with neutrophilia at 2 hr post-transport (P<0.05); the former levels remained higher than those in the controls for 4 hr. The numbers of lymphocytes, monocytes, eosinophils and CD25+ lymphocytes remained unchanged throughout the observations. The number of circulating NK cells in Group M increased during transport and peaked shortly after transport (P<0.05). Subsequent to these time points, the counts in Group F showed a trend toward elevation. The circulating NK cell counts were positively correlated with the plasma cortisol level during transport (M, r=0.755, P<0.0005; F, r=0.653; P<0.005). These results suggest that circulating NK cells might be more rapidly mobilized than other leukocytes. Therefore, they might reflect acute stress levels in calves during road transportation.

  8. Resveratrol Administration Increases Transthyretin Protein Levels, Ameliorating AD Features: The Importance of Transthyretin Tetrameric Stability

    PubMed Central

    Santos, Luís Miguel; Rodrigues, Daniela; Alemi, Mobina; Silva, Sara Costa; Ribeiro, Carlos Alexandre; Cardoso, Isabel

    2016-01-01

    Previous in vivo work showed that resveratrol has beneficial effects in Alzheimer’s disease (AD) pathology, resulting in increased expression of transthyretin (TTR). TTR binds amyloid-beta (Aβ) peptide, avoiding its aggregation and toxicity, and is reduced in the cerebrospinal fluid (CSF) and plasma in AD. Further, resveratrol binds TTR, stabilizing the native TTR tetrameric structure. To further explore the mechanism of neuroprotection conferred by TTR in AD, resveratrol was administered in the diet to 5- to 8-month-old AD transgenic female mice carrying just 1 copy of the mouse TTR gene for 2 months. Effects in brain Aβ burden were evaluated by immunohistochemistry, and total brain Aβ levels by ELISA, showing a striking decrease in both parameters in treated animals. In addition, total brain lipoprotein-related receptor protein 1 (LRP1) levels were increased in treated animals, although its gene expression was unaltered. To further understand the mechanism(s) underlying such improvement in AD features, we measured TTR plasma levels, showing that TTR increased in resveratrol-treated mice, whereas liver TTR gene transcription was not altered. These results strengthen the stability hypothesis, which postulates that TTR is unstable in AD, leading to accelerated clearance and lower levels. Therefore, resveratrol, which stabilizes the TTR tetramer results in TTR-normalized clearance, increases the protein plasma levels. In turn, stabilized TTR binds more strongly to Aβ peptide, avoiding its aggregation. Our results represent a step forward in the understanding of the mechanism underlying TTR protection in AD and highlight the possibility of using TTR stabilization as a therapeutic target in AD. PMID:27385446

  9. Rotational stress-induced increase in epinephrine levels delays cutaneous wound healing in mice.

    PubMed

    Romana-Souza, Bruna; Otranto, Marcela; Vieira, Andreza M; Filgueiras, Cláudio C; Fierro, Iolanda M; Monte-Alto-Costa, Andréa

    2010-03-01

    Stress impairs wound healing of cutaneous lesions; however, the mechanism is still unclear. The aim of this study was to evaluate the effects of rotational stress on cutaneous wound healing in mice and propose a mechanism. Male mice were spun at 45 rpm for 15 min every hour beginning 3 days before wounding until euthanasia. Control animals were not subjected to stress. To confirm that catecholamines participate in stress-induced delay of wound healing, mice were treated daily with propranolol. An excisional lesion was created and measured. Seven and 14 days later, animals were killed and lesions collected. Sections were stained with hematoxylin-eosin and immunostained for alpha-smooth muscle actin and proliferating cell nuclear antigen. Matrix metalloproteinase (MMP)-2 and -9 activity, nitrite levels, and tumor necrosis factor-alpha (TNF-alpha) expression were measured in the wounds. In addition, murine skin fibroblast cultures were treated with high levels of epinephrine and fibroblast activity was evaluated. Stressed mice exhibited reduced locomotor activity and increased normetanephrine plasma levels. Rotational stress was associated with decreased wound contraction, reduced re-epithelialization, reduced MMP-2 and MMP-9 activation, but with strongly increased nitrite levels. Furthermore, inflammatory cell infiltration, TNF-alpha expression, myofibroblastic differentiation, and angiogenesis were all delayed in the stress group. Propranolol administration reversed the deleterious effects of stress on wound contraction and re-epithelialization. High epinephrine concentrations increased murine skin fibroblast proliferation and nitric oxide synthesis, and strongly inhibited skin fibroblast migration and both pro- and active MMP-2. In conclusion, rotational stress impairs cutaneous wound healing due to epinephrine increased levels.

  10. Increased serum level of homocysteine correlates with retinal nerve fiber layer thinning in diabetic retinopathy

    PubMed Central

    Srivastav, Khushboo; Mahdi, Abbas A.; Shukla, Rajendra K.; Meyer, Carsten H.; Akduman, Levent; Khanna, Vinay K.

    2016-01-01

    Purpose To study the correlation between serum levels of vitamin B12, folic acid, and homocysteine and the severity of diabetic retinopathy and the correlation with retinal nerve fiber layer (RNFL) thinning on spectral domain optical coherence tomography (SD-OCT). Methods In a tertiary care center–based prospective cross-sectional study, 60 consecutive cases and 20 healthy controls in the age group of 40–65 years were included. The eyes of the cases were divided into three groups according to Early Treatment Diabetic Retinopathy Study (ETDRS) classification: diabetes mellitus without retinopathy (n = 20), non-proliferative diabetic retinopathy with macular edema (n = 20), and proliferative diabetic retinopathy with macular edema (n = 20). The serum levels of vitamin B12 and folic acid were measured using a standard protocol. The serum homocysteine assay was performed using an enzyme-linked immunosorbent assay (ELISA) kit. Average RNFL thickness was measured using SD-OCT. Statistical analysis was used to assess the correlations between the study variables. Results Increased severity of diabetic retinopathy was found to correlate with an increase in the serum levels of homocysteine (F = 53.79; p<0.001). The mean serum levels of vitamin B12 and folic acid were found to be within the normal reference range. A positive correlation was found between retinal nerve fiber layer thinning and serum levels of homocysteine (p<0.001). Conclusions This study, for the first time, demonstrated a correlation between increased homocysteine with a decrease in RNFL thickness and increased severity of diabetic retinopathy. PMID:27994434

  11. Genetic increase in brain-derived neurotrophic factor levels enhances learning and memory.

    PubMed

    Nakajo, Yukako; Miyamoto, Susumu; Nakano, Yoshikazu; Xue, Jing-Hui; Hori, Takuya; Yanamoto, Hiroji

    2008-11-19

    Brain-derived neurotrophic factor (BDNF), a neurotrophin, is known to promote neuronal differentiation stimulating neurite outgrowth in the developing CNS, and is also known to modulate synaptic plasticity, thereby contributing to learning and memory in the mature brain. Here, we investigated the role of increased levels of intracerebral BDNF in learning and memory function. Using genetically engineered transgenic BDNF overexpressing mice (RTG-BDNF), young adult, homozygous (+/+), heterozygous (+/-), or wild-type (-/-) littermates, we analyzed escape latency to a hidden-platform and swimming velocity in the Morris Water Maze test (MWM) with modifications for the mice. The MWM comprised 4 trials per day over 5 consecutive days (sessions) without prior or subsequent training. In a separate set of animals, BDNF protein levels in the cortex, thalamostriatum and the hippocampus were measured quantitatively using ELISA. In the BDNF (+/-) mice, the BDNF levels in the cortex, the thalamostriatum and the hippocampus were significantly high, compared to the wild-type littermates; 238%, 158%, and 171%, respectively (P<0.01, one-way ANOVA and a post-hoc test in each region). The BDNF levels in the BDNF (+/+) mice were not elevated. The BDNF (+/-), but not the (+/+) mice, demonstrated significantly shorter escape latency, shorter total path length in the MWM, and more frequent arrivals at the location where the platform had been placed previously in the probe trial, compared with the wild-type littermates (P<0.05, at each time pint). Because the maximum swimming velocity was not affected in the BDNF-transgenic mice, increased BDNF levels in the brain were found to enhance spatial learning and memory function. Although it has been postulated that excessive BDNF is deteriorating for neuronal survival or neurite outgrowth, further investigations are needed to clarify the mechanism of paradoxical lack of increase in BDNF levels in the (+/+) mouse brain.

  12. Increased miR-132 level is associated with visual memory dysfunction in patients with depression

    PubMed Central

    Liu, Ye; Yang, Xiao; Zhao, Liansheng; Zhang, Jian; Li, Tao; Ma, Xiaohong

    2016-01-01

    Background Impaired visual memory seems to be a core feature of depression, while increased microRNA-132 (miR-132) levels have been widely reported in depression patients. The authors aimed to explore the relationship between miR-132 changes and visual memory deficits in unmedicated patients with major depressive disorder (MDD). Patients and methods A total of 62 medication-free MDD patients and 73 matched healthy controls (HCs) were tested for miR-132 expression level in peripheral blood using quantitative real-time polymerase chain reaction. We used a computerized neurocognitive task from the Cambridge Neuropsychological Test Automated Battery (CANTAB) – pattern recognition memory (PRM) task – as a measurement of visual memory. The relationship between visual memory, miR-132 expression level, and clinical symptoms was explored in patients with MDD. Results Upregulated miR-132 expression levels were seen in MDD patients but not in HCs. Two-sample t-tests showed that MDD patients had decreased visual memory, mainly memory delayed compared to that of HCs. Correlation analyses revealed that in MDD patients, increased miR-132 expression levels were significantly correlated with visual memory as measured by the CANTABPRM. Hamilton Rating Scale for Anxiety scores were negatively correlated with PRM – number correct (immediate) and PRM – percent correct (immediate). Limitations The main limitations were missing data and lack of follow-up studies. Conclusion Our study suggests that increased miR-132 expression levels were associated with visual memory deficits, which may underlie the pathophysiology of MDD. In individuals with depression, immediate visual memory defects were positively correlated with anxiety symptoms. PMID:27877044

  13. Catalytic mechanism and kinase interactions of ABA-signaling PP2C phosphatases.

    PubMed

    Zhou, X Edward; Soon, Fen-Fen; Ng, Ley-Moy; Kovach, Amanda; Suino-Powell, Kelly M; Li, Jun; Yong, Eu-Leong; Zhu, Jian-Kang; Xu, H Eric; Melcher, Karsten

    2012-05-01

    Abscisic acid (ABA) is an essential hormone that controls plant growth, development and responses to abiotic stresses. ABA signaling is mediated by type 2C protein phosphatases (PP2Cs), including HAB1 and ABI2, which inhibit stress-activated SnRK2 kinases and whose activity is regulated by ABA and ABA receptors. Based on biochemical data and our previously determined crystal structures of ABI2 and the SnRK2.6-HAB1 complex, we present the catalytic mechanism of PP2C and provide new insight into PP2C-SnRK2 interactions and possible roles of other SnRK2 kinases in ABA signaling.

  14. Increasing Hippocampal Acetylcholine Levels Enhances Behavioral Performance in an Animal Model of Diencephalic Amnesia

    PubMed Central

    Roland, Jessica J.; Mark, Katherine; Vetreno, Ryan P.; Savage, Lisa M.

    2008-01-01

    Pyrithiamine-induced thiamine deficiency (PTD) was used to produce a rodent model of Wernicke-Korsakoff syndrome that results in acute neurological disturbances, thalamic lesions, and learning and memory impairments. There is also cholinergic septo-hippocampal dysfunction in the PTD model. Systemic (Experiment 1) and intrahippocampal (Experiment 2) injections of the acetylcholinesterase inhibitor physostigmine were administered to determine if increasing acetylcholine levels would eliminate the behavioral impairment produced by PTD. Prior to spontaneous alternation testing, rats received injections of either physostigmine (systemic = 0.075 mg/kg; intrahippocampal = 20, 40 ng/µl) or saline. In Experiment 2, intrahippocampal injections of physostigmine significantly enhanced alternation rates in the PTD-treated rats. In addition, although intrahippocampal infusions of 40 ng of physostigmine increased the available amount of ACh in both Pair-fed (PF) and PTD rats, it did so to a greater extent in PF rats. The increase in ACh levels induced by the direct hippocampal application of physostigmine in the PTD model likely increased activation of the extended limbic system, which was dysfunctional, and therefore led to recovery of function on the spontaneous alternation task. In contrast, the lack of behavioral improvement by intrahippocampal physostigmine infusion in the PF rats, despite a greater rise in hippocampal ACh levels, supports the theory that there is a optimal range of cholinergic tone for optimal behavioral and hippocampal function. PMID:18706897

  15. Salicylic Acid Treatment Increases the Levels of Triterpene Glycosides in Black Cohosh (Actaea Racemosa) Rhizomes.

    PubMed

    De Capite, Annette; Lancaster, Tyler; Puthoff, David

    2016-01-01

    Black cohosh (Actaea racemosa) serves as the host plant for the Appalachian azure butterfly, Celastrina neglectamajor. Overharvesting of Black cohosh for the dietary supplement industry may result in its extirpation, and may also cause the elimination of the dependent butterfly. One way to increase or maintain the number of host plants in forested environments would be to reduce the number harvested, for example by increasing the levels of the desired metabolites in Black cohosh rhizomes. The secondary metabolites actein and deoxyactein are triterpene glycosides and are among the compounds associated with the putative activity of Black cohosh extracts. Acetein and deoxyacetein are used to standardize Black cohosh supplements. To gain an understanding of mechanisms that may control actein and deoxyactein accumulation, Black cohosh rhizomes were treated with exogenous salicylic acid, jasmonic acid, or ethylene, or were mechanically wounded. Salicylic acid treatment significantly increased the levels of actein and deoxyactein in the rhizome of Black cohosh, suggesting that the synthesis of triterpene glycosides is controlled in part by salicylic acid. Using salicylic acid or related chemicals to increase the levels of actein and deoxyactein in rhizomes may help supply the supplement industry and, simultaneously, help conserve Black cohosh and species dependent upon it.

  16. Mitochondrial impairment increases FL-PINK1 levels by calcium-dependent gene expression☆

    PubMed Central

    Gómez-Sánchez, Rubén; Gegg, Matthew E.; Bravo-San Pedro, José M.; Niso-Santano, Mireia; Alvarez-Erviti, Lydia; Pizarro-Estrella, Elisa; Gutiérrez-Martín, Yolanda; Alvarez-Barrientos, Alberto; Fuentes, José M.; González-Polo, Rosa Ana; Schapira, Anthony H.V.

    2014-01-01

    Mutations of the PTEN-induced kinase 1 (PINK1) gene are a cause of autosomal recessive Parkinson's disease (PD). This gene encodes a mitochondrial serine/threonine kinase, which is partly localized to mitochondria, and has been shown to play a role in protecting neuronal cells from oxidative stress and cell death, perhaps related to its role in mitochondrial dynamics and mitophagy. In this study, we report that increased mitochondrial PINK1 levels observed in human neuroblastoma SH-SY5Y cells after carbonyl cyanide m-chlorophelyhydrazone (CCCP) treatment were due to de novo protein synthesis, and not just increased stabilization of full length PINK1 (FL-PINK1). PINK1 mRNA levels were significantly increased by 4-fold after 24 h. FL-PINK1 protein levels at this time point were significantly higher than vehicle-treated, or cells treated with CCCP for 3 h, despite mitochondrial content being decreased by 29%. We have also shown that CCCP dissipated the mitochondrial membrane potential (Δψm) and induced entry of extracellular calcium through L/N-type calcium channels. The calcium chelating agent BAPTA-AM impaired the CCCP-induced PINK1 mRNA and protein expression. Furthermore, CCCP treatment activated the transcription factor c-Fos in a calcium-dependent manner. These data indicate that PINK1 expression is significantly increased upon CCCP-induced mitophagy in a calcium-dependent manner. This increase in expression continues after peak Parkin mitochondrial translocation, suggesting a role for PINK1 in mitophagy that is downstream of ubiquitination of mitochondrial substrates. This sensitivity to intracellular calcium levels supports the hypothesis that PINK1 may also play a role in cellular calcium homeostasis and neuroprotection. PMID:24184327

  17. Mitochondrial impairment increases FL-PINK1 levels by calcium-dependent gene expression.

    PubMed

    Gómez-Sánchez, Rubén; Gegg, Matthew E; Bravo-San Pedro, José M; Niso-Santano, Mireia; Alvarez-Erviti, Lydia; Pizarro-Estrella, Elisa; Gutiérrez-Martín, Yolanda; Alvarez-Barrientos, Alberto; Fuentes, José M; González-Polo, Rosa Ana; Schapira, Anthony H V

    2014-02-01

    Mutations of the PTEN-induced kinase 1 (PINK1) gene are a cause of autosomal recessive Parkinson's disease (PD). This gene encodes a mitochondrial serine/threonine kinase, which is partly localized to mitochondria, and has been shown to play a role in protecting neuronal cells from oxidative stress and cell death, perhaps related to its role in mitochondrial dynamics and mitophagy. In this study, we report that increased mitochondrial PINK1 levels observed in human neuroblastoma SH-SY5Y cells after carbonyl cyanide m-chlorophelyhydrazone (CCCP) treatment were due to de novo protein synthesis, and not just increased stabilization of full length PINK1 (FL-PINK1). PINK1 mRNA levels were significantly increased by 4-fold after 24h. FL-PINK1 protein levels at this time point were significantly higher than vehicle-treated, or cells treated with CCCP for 3h, despite mitochondrial content being decreased by 29%. We have also shown that CCCP dissipated the mitochondrial membrane potential (Δψm) and induced entry of extracellular calcium through L/N-type calcium channels. The calcium chelating agent BAPTA-AM impaired the CCCP-induced PINK1 mRNA and protein expression. Furthermore, CCCP treatment activated the transcription factor c-Fos in a calcium-dependent manner. These data indicate that PINK1 expression is significantly increased upon CCCP-induced mitophagy in a calcium-dependent manner. This increase in expression continues after peak Parkin mitochondrial translocation, suggesting a role for PINK1 in mitophagy that is downstream of ubiquitination of mitochondrial substrates. This sensitivity to intracellular calcium levels supports the hypothesis that PINK1 may also play a role in cellular calcium homeostasis and neuroprotection.

  18. Evidence that elevated CO2 levels can indirectly increase rhizosphere denitrifier activity

    NASA Technical Reports Server (NTRS)

    Smart, D. R.; Ritchie, K.; Stark, J. M.; Bugbee, B.

    1997-01-01

    We examined the influence of elevated CO2 concentration on denitrifier enzyme activity in wheat rhizoplanes by using controlled environments and solution culture techniques. Potential denitrification activity was from 3 to 24 times higher on roots that were grown under an elevated CO2 concentration of 1,000 micromoles of CO2 mol-1 than on roots grown under ambient levels of CO2. Nitrogen loss, as determined by a nitrogen mass balance, increased with elevated CO2 levels in the shoot environment and with a high NO3- concentration in the rooting zone. These results indicated that aerial CO2 concentration can play a role in rhizosphere denitrifier activity.

  19. Increased levels of antibodies to cytokeratin 18 in patients with rheumatoid arthritis and ischaemic heart disease

    PubMed Central

    Mattey, D; Dawes, P; Nixon, N; Goh, L; Banks, M; Kitas, G

    2004-01-01

    Objective: To determine whether raised levels of antibodies to CK18 in patients with RA are associated with ischaemic heart disease (IHD). Methods: IgA, IgG, and IgM antibodies to CK18 were measured by enzyme linked immunosorbent assay (ELISA) in patients with RA with (n = 34) or without (n = 28) IHD. The relationship between CK18 antibody levels and markers of inflammatory and/or cardiovascular disease was examined. Results: Initial analysis showed that IgG antibody levels to CK18 were higher in patients with RA with IHD than in those without (50.1 v 34.5 AU, p = 0.047), although significance was lost after correction for multiple comparisons. Further analysis showed a significant difference (p = 0.015) between patients with IHD and a positive family history, and patients without IHD and a negative family history (53.7 v 29.0 AU, Kruskal-Wallis multiple comparison Z value test). There was also a significant trend of increasing 10 year cardiovascular risk with increasing CK18 IgG antibody levels (p = 0.01). No association was found between CK18 antibody levels and conventional markers of inflammation or cardiovascular disease, but an association was found between levels of CK18 IgG and IgG antibodies to cytomegalovirus (CMV) (Spearman's rs = 0.379, pcorr = 0.04). No evidence for cross reactivity of CK18 antibodies with CMV antigens was found. Conclusion: Levels of IgG antibodies to CK18 are raised in patients with RA with IHD, particularly if they also have a positive family history. This may reflect damage to CK18 containing cells in the cardiac vasculature and/or in atherosclerotic plaques, and may be a useful additional marker for the identification of patients with, or likely to develop, IHD. PMID:15020337

  20. Short Communication: High Cellular Iron Levels Are Associated with Increased HIV Infection and Replication

    PubMed Central

    Chang, Hsiang-Chun; Bayeva, Marina; Taiwo, Babafemi; Palella, Frank J.; Hope, Thomas J.

    2015-01-01

    Abstract HIV is a pandemic disease, and many cellular and systemic factors are known to alter its infectivity and replication. Earlier studies had suggested that anemia is common in HIV-infected patients; however, higher iron was also observed in AIDS patients prior to the introduction of antiretroviral therapy (ART). Therefore, the relationship between iron and viral infection is not well delineated. To address this issue, we altered the levels of cellular iron in primary CD4+ T cells and showed that higher iron is associated with increased HIV infection and replication. In addition, HIV infection alone leads to increased cellular iron, and several ART drugs increase cellular iron independent of HIV infection. Finally, HIV infection is associated with increased serum iron in HIV-positive patients regardless of treatment with ART. These results establish a relationship between iron and HIV infection and suggest that iron homeostasis may be a viable therapeutic target for HIV. PMID:25291189

  1. Short communication: high cellular iron levels are associated with increased HIV infection and replication.

    PubMed

    Chang, Hsiang-Chun; Bayeva, Marina; Taiwo, Babafemi; Palella, Frank J; Hope, Thomas J; Ardehali, Hossein

    2015-03-01

    HIV is a pandemic disease, and many cellular and systemic factors are known to alter its infectivity and replication. Earlier studies had suggested that anemia is common in HIV-infected patients; however, higher iron was also observed in AIDS patients prior to the introduction of antiretroviral therapy (ART). Therefore, the relationship between iron and viral infection is not well delineated. To address this issue, we altered the levels of cellular iron in primary CD4(+) T cells and showed that higher iron is associated with increased HIV infection and replication. In addition, HIV infection alone leads to increased cellular iron, and several ART drugs increase cellular iron independent of HIV infection. Finally, HIV infection is associated with increased serum iron in HIV-positive patients regardless of treatment with ART. These results establish a relationship between iron and HIV infection and suggest that iron homeostasis may be a viable therapeutic target for HIV.

  2. Increased serum levels of lipogenic enzymes in patients with severe liver steatosis

    PubMed Central

    2012-01-01

    Background Lipid metabolism is altered in subjects with liver steatosis. FAS is a key enzyme in de novo lipogenesis and both FAS gene expression and enzymatic activity are primarily regulated by metabolic signals in the liver. Lipoprotein lipase (LPL), the rate-limiting enzyme for the hydrolysis of core triglycerides, plays a pivotal role in lipid metabolism. This study aims to investigate if circulating levels of FAS and LPL could be clinically associated with liver steatosis. Methods In this work, we present data obtained from a subsample of 94 subjects with liver steatosis enrolled by NUTRIEPA study, a nutritional trial in subjects with liver steatosis. Serum levels of FAS protein and LPL activity were evaluated by ELISA test and by a fluorescent method, respectively. The diagnosis and the degree of liver steatosis were based on laboratory and ecographic measurements. Statistical methods included Kruskal-Wallis analysis of variance and Wilcoxon signed-rank test, where appropriate. The χ2 test has been performed to analyse categorical variables. Results The subjects with severe steatosis had significantly higher serum levels of FAS protein and LPL activity compared to subjects with mild and moderate liver steatosis. Moreover, a positive trend in serum levels of FAS expression from lower to higher degree of steatosis was also detected. Conclusions We describe a relationship between human liver steatosis and elevated levels of circulating lipogenic enzymes. Increased serum levels of FAS expression and LPL activity could be considered a marker of severe liver steatosis. PMID:23110339

  3. Serum betatrophin levels are increased and associated with insulin resistance in patients with polycystic ovary syndrome.

    PubMed

    Qu, Qinglan; Zhao, Dongmei; Zhang, Fengrong; Bao, Hongchu; Yang, Qiuhua

    2017-02-01

    Objective Betatrophin is a newly identified circulating protein that is significantly associated with type 2 diabetes mellitus (T2DM), adiposity, and metabolic syndrome. The aim of this study was to investigate whether betatrophin levels and polycystic ovary syndrome (PCOS) were associated. Methods Circulating betatrophin levels were measured in 162 patients with PCOS and 156 matched control females using specific enzyme-linked immunosorbent assay kits. Correlations between betatrophin levels and PCOS incidence as well as multiple key endocrine PCOS parameters were analyzed using multiple statistical methods. Results Betatrophin levels were significantly increased in patients with PCOS (685.3 ± 27.7 vs. 772.6 ± 42.5 pg/ml). When sub-grouping all investigated subjects according to the presence of insulin resistance, women with PCOS and insulin resistance exhibited markedly higher betatrophin concentrations. Furthermore, betatrophin levels were significantly correlated with fasting insulin levels and homeostatic model assessment of insulin resistance only in females with PCOS ( r = 0.531 and r = 0.628, respectively). Conclusion We provide the first report that betatrophin is strongly associated with PCOS. This study suggests that betatrophin may potentially serve as an independent predictor for the development of PCOS in at-risk women, especially those with insulin resistance.

  4. Benefits and costs of increased levels of corticosterone in seabird chicks

    USGS Publications Warehouse

    Kitaysky, A.S.; Kitaiskaia, E.V.; Piatt, J.F.; Wingfield, J.C.

    2003-01-01

    Seabird chicks respond to food shortages by increasing corticosterone (cort) secretion, which is probably associated with fitness benefits and costs. To examine this, we experimentally increased levels of circulating cort in captive black-legged kittiwake chicks fed ad libitum. We found that cort-implanted chicks begged more frequently and were more aggressive compared to controls. These behavioral modifications must be beneficial to chicks as they facilitate acquisition of food from the parents and might trigger brood reduction and reduced competition for food. Cort-implanted chicks also increased food intake; however, their growth rates were similar to controls. To examine the costs of chronically increased circulating levels of cort, we removed cort implants and, after a 10-day recovery period, tested cognitive abilities of young kittiwakes. We found that the ability of kittiwakes to associate a visual cue with the presence of food in a choice situation was compromised by the experimental elevation of cort during development. To examine the long-term costs of increased levels of cort, 8 months later we tested the performance of the same individuals in a spatial task requiring them to make a detour around a barrier in order to escape from an enclosure. Individuals treated with cort during development took significantly more time to solve this task compared to controls. The results of this study suggest that the adrenocortical response of a developing bird to environmental stressors is associated with both benefits (increased food intake, foraging behavior, and aggression) and costs (low growth efficiency and compromised cognitive abilities later in life). This provides an evolutionary framework for relating juvenile physiological traits to fitness of birds in subsequent life-history stages. ?? 2003 Elsevier Science (USA). All rights reserved.

  5. RING Type E3 Ligase CaAIR1 in Pepper Acts in the Regulation of ABA Signaling and Drought Stress Response.

    PubMed

    Park, Chanmi; Lim, Chae Woo; Baek, Woonhee; Lee, Sung Chul

    2015-09-01

    Several E3 ubiquitin ligases have been associated with the response to abiotic and biotic stresses in higher plants. Here, we report that the hot pepper (Capsicum annuum) ABA-Insensitive RING protein 1 gene (CaAIR1) is essential for a hypersensitive response to drought stress. CaAIR1 contains a C3HC4-type RING finger motif, which plays a role for attachment of ubiquitins to the target protein, and a putative transmembrane domain. The expression levels of CaAIR1 are up-regulated in pepper leaves by ABA treatments, drought and NaCl, suggesting its role in the response to abiotic stress. Our analysis showed that CaAIR1 displays self-ubiquitination and is localized in the nucleus. We generated CaAIR1-silenced peppers via virus-induced gene silencing (VIGS) and CaAIR1-overexpressing (OX) transgenic Arabidopsis plants to evaluate their responses to ABA and drought. VIGS of CaAIR1 in pepper plants conferred an enhanced tolerance to drought stress, which was accompanied by low levels of transpirational water loss in the drought-treated leaves. CaAIR1-OX plants displayed an impaired sensitivity to ABA during seed germination, seedling and adult stages. Moreover, these plants showed enhanced sensitivity to drought stress because of reduced stomatal closure and decreased expression of stress-responsive genes. Thus, our data indicate that CaAIR1 is a negative regulator of the ABA-mediated drought stress tolerance mechanism.

  6. A gene stacking approach leads to engineered plants with highly increased galactan levels in Arabidopsis

    SciTech Connect

    Gondolf, Vibe M.; Stoppel, Rhea; Ebert, Berit; Rautengarten, Carsten; Liwanag, April J.M.; Loqué, Dominique; Scheller, Henrik V.

    2014-12-10

    Background: Engineering of plants with a composition of lignocellulosic biomass that is more suitable for downstream processing is of high interest for next-generation biofuel production. Lignocellulosic biomass contains a high proportion of pentose residues, which are more difficult to convert into fuels than hexoses. Therefore, increasing the hexose/pentose ratio in biomass is one approach for biomass improvement. A genetic engineering approach was used to investigate whether the amount of pectic galactan can be specifically increased in cell walls of Arabidopsis fiber cells, which in turn could provide a potential source of readily fermentable galactose. Results: First it was tested if overexpression of various plant UDP-glucose 4-epimerases (UGEs) could increase the availability of UDP-galactose and thereby increase the biosynthesis of galactan. Constitutive and tissue-specific expression of a poplar UGE and three Arabidopsis UGEs in Arabidopsis plants could not significantly increase the amount of cell wall bound galactose. We then investigated co-overexpression of AtUGE2 together with the β-1,4-galactan synthase GalS1. Co-overexpression of AtUGE2 and GalS1 led to over 80% increase in cell wall galactose levels in Arabidopsis stems, providing evidence that these proteins work synergistically. Furthermore, AtUGE2 and GalS1 overexpression in combination with overexpression of the NST1 master regulator for secondary cell wall biosynthesis resulted in increased thickness of fiber cell walls in addition to the high cell wall galactose levels. Immunofluorescence microscopy confirmed that the increased galactose was present as β-1,4-galactan in secondary cell walls. Conclusions: This approach clearly indicates that simultaneous overexpression of AtUGE2 and GalS1 increases the cell wall galactose to much higher levels than can be achieved by overexpressing either one of these proteins alone. Moreover, the increased galactan content in

  7. A gene stacking approach leads to engineered plants with highly increased galactan levels in Arabidopsis

    DOE PAGES

    Gondolf, Vibe M.; Stoppel, Rhea; Ebert, Berit; ...

    2014-12-10

    Background: Engineering of plants with a composition of lignocellulosic biomass that is more suitable for downstream processing is of high interest for next-generation biofuel production. Lignocellulosic biomass contains a high proportion of pentose residues, which are more difficult to convert into fuels than hexoses. Therefore, increasing the hexose/pentose ratio in biomass is one approach for biomass improvement. A genetic engineering approach was used to investigate whether the amount of pectic galactan can be specifically increased in cell walls of Arabidopsis fiber cells, which in turn could provide a potential source of readily fermentable galactose. Results: First it was tested ifmore » overexpression of various plant UDP-glucose 4-epimerases (UGEs) could increase the availability of UDP-galactose and thereby increase the biosynthesis of galactan. Constitutive and tissue-specific expression of a poplar UGE and three Arabidopsis UGEs in Arabidopsis plants could not significantly increase the amount of cell wall bound galactose. We then investigated co-overexpression of AtUGE2 together with the β-1,4-galactan synthase GalS1. Co-overexpression of AtUGE2 and GalS1 led to over 80% increase in cell wall galactose levels in Arabidopsis stems, providing evidence that these proteins work synergistically. Furthermore, AtUGE2 and GalS1 overexpression in combination with overexpression of the NST1 master regulator for secondary cell wall biosynthesis resulted in increased thickness of fiber cell walls in addition to the high cell wall galactose levels. Immunofluorescence microscopy confirmed that the increased galactose was present as β-1,4-galactan in secondary cell walls. Conclusions: This approach clearly indicates that simultaneous overexpression of AtUGE2 and GalS1 increases the cell wall galactose to much higher levels than can be achieved by overexpressing either one of these proteins alone. Moreover, the increased galactan content in fiber cells while

  8. Low-level laser as a device for increase of drug concentration in the kidney

    NASA Astrophysics Data System (ADS)

    Koultchavenia, Ekaterina V.

    2001-01-01

    In the West Siberia every tenth tuberculous patient has an extra pulmonary lesion. Urogenital tuberculosis cases are in the first place in occurrence among extra pulmonary forms. Complicated and widespread lesions of kidney are prevailing. The high concentration of anti-tuberculous drugs in the lesion locus is one of the most important component in the success treatment of tuberculosis, including nephrotyberculosis. We put the aim to increase the isoniazid concentration in tuberculous kidney by low-level laser therapy. It was proved that the laser therapy at the expense of improving of the blood microcirculation ensures to increase drug concentration in the lesion locus in 9 times.

  9. Can Population Levels of Physical Activity be Increased? Global Evidence and Experience

    PubMed Central

    Pratt, Michael; Perez, Lilian G.; Goenka, Shifalika; Brownson, Ross C.; Bauman, Adrian; Sarmiento, Olga Lucia; Hallal, Pedro C.

    2016-01-01

    Physical inactivity is one of the most important contributors to the global burden of disease and has become a global public health priority. We review the evidence on physical activity (PA) interventions, actions, and strategies that have the greatest potential to increase PA at the population level. Using the socio-ecological framework to conceptualize PA interventions, we show that PA can be targeted at multiple levels of influence and by multiple sectors outside the health system. Examples of promoting PA on a national scale are presented from Finland, Canada, Brazil, and Colombia. A strong policy framework, consistent investment in public health programs, multi-sectoral support and actions, and good surveillance characterize each of these success stories. Increasing PA globally will depend on successfully applying and adapting these lessons around the world taking into account country, culture, and context. PMID:25304047

  10. Increased total serum random cortisol levels predict mortality in critically ill trauma patients.

    PubMed

    Pandya, Urmil; Polite, Nathan; Wood, Teresa; Lieber, Michael

    2014-11-01

    Dysfunction in the hypothalamopituitary adrenal axis is thought to exist; however, there continues to be controversy about what level of serum cortisol corresponds to adrenal insufficiency. Few studies have focused on the significance of serum random cortisol in the critically ill trauma patient. Trauma patients with total serum random cortisol levels drawn in the intensive care unit within the first seven days of hospitalization were retrospectively reviewed. The primary outcome measured was in-hospital mortality. Two hundred forty-two patients were analyzed. Nonsurvivors had significantly higher mean cortisol levels than survivors (28.7 ± 15.80 μg/dL vs 22.9 ± 12.35 μg/dL, P = 0.01). Patients with cortisol 30 μg/dL or greater were more likely to die with odds ratio of 2.7 (95% confidence interval [CI], 1.5 to 5). The odds ratio increased to 4.0 and 3.8 (95% CI, 1.4 to 11.4 and 1.3 to 10.9) when cortisol was drawn on hospital Day 2 and Days 3 through 7, respectively. Among nonsurvivors, patients with an injury severity score less than 25 had significantly higher cortisol levels than patients with an Injury Severity Score 25 or higher (35.3 ± 19.21 μg/dL vs 25.7 ± 13.21 μg/dL, P = 0.009). Patients with massive transfusion, traumatic brain injury, spinal cord injury, or solid organ injury did not have significantly different cortisol levels. The covariate-adjusted area under the receiver operating characteristic curve indicated that cortisol level has a 77 per cent accuracy in differentiating survivors from nonsurvivors. Higher cortisol levels were predictive of mortality in critically ill trauma patients. Whether serum cortisol level is a marker that can be modified remains an area of interest for future study.

  11. Tenascin-C Deficiency in Apo E−/− Mouse Increases Eotaxin Levels: Implications for Atherosclerosis

    PubMed Central

    Wang, Lai; Shah, Prediman K.; Wang, Wei; Song, Lei; Yang, Mingjie; Sharifi, Behrooz G.

    2013-01-01

    Aim To investigate the potential role of inflammatory cytokines in apo E−/− mouse in response to deletion of Tenascin-C (TNC) gene. Methods and results We used antibody array and ELISA to compare the profile of circulating inflammatory cytokines in apo E−/− mice and apo E−/− TNC−/− double knockout mice. In addition, tissue culture studies were performed to investigate the activity of cells from each mouse genotype in vitro. Cytokine array analysis and subsequent ELISA showed that circulating eotaxin levels were selectively and markedly increased in response to TNC gene deletion in apo E−/− mice. In addition, considerable variation was noted in the circulating level of eotaxin among the control apo E−/− mouse group. Inbreeding of apo E−/− mice with high or low levels of plasma eotaxin showed that the level of eotaxin per se determines the extent of atherosclerosis in this mouse genotype. While endothelial cells from apo E−/− mice had low level of eotaxin expression, cells derived from apo E−/−TNC−/− mice expressed a high level of eotaxin. Transient transfection of eotaxin promoter-reporter constructs revealed that eotaxin expression is regulated at the transcriptional level by TNC. Histochemical analysis of aortic sections revealed the massive accumulation of mast cells in the adventitia of double KO mice lesions whereas no such accumulation was detected in the control group. Plasma from the apo E−/−TNC−/− mice markedly stimulated mast cell migration whereas plasma from the apo E−/− mice had no such effect. Conclusion These observations support the emerging hypothesis that TNC expression controls eotaxin level in apo E−/− mice and that this chemokine plays a key role in the development of atherosclerosis. PMID:23433402

  12. Electrical signaling, stomatal conductance, ABA and ethylene content in avocado trees in response to root hypoxia.

    PubMed

    Gil, Pilar M; Gurovich, Luis; Schaffer, Bruce; García, Nicolás; Iturriaga, Rodrigo

    2009-02-01

    Avocado (Persea americana Mill.) trees are among the most sensitive of fruit tree species to root hypoxia as a result of flooded or poorly drained soil. Similar to drought stress, an early physiological response to root hypoxia in avocado is a reduction of stomatal conductance. It has been previously determined in avocado trees that an extracellular electrical signal between the base of stem and leaves is produced and related to reductions in stomatal conductance in response to drought stress. The current study was designed to determine if changes in the extracellular electrical potential between the base of the stem and leaves in avocado trees could also be detected in response to short-term (min) or long-term (days) root hypoxia, and if these signals could be related to stomatal conductance (gs), root and leaf ABA and ACC concentrations, ethylene emission from leaves and leaf abscission. In contrast to previous observations for drought-stressed trees, short-term or long-term root hypoxia did not stimulate an electrical potential difference between the base of the stem and leaves. Short-term hypoxia did not result in a significant decrease in gs compared with plants in the control treatment, and no differences in ABA concentration were found between plants subjected to hypoxia and control plants. Long-term hypoxia in the root zone resulted in a significant decrease in gs, increased leaf ethylene and increased leaf abscission. The results indicate that for avocado trees exposed to root hypoxia, electrical signals do not appear to be the primary root-to-shoot communication mechanism involved in signaling for stomatal closure as a result of hypoxia in the root zone.

  13. Electrical signaling, stomatal conductance, ABA and Ethylene content in avocado trees in response to root hypoxia

    PubMed Central

    Gurovich, Luis; Schaffer, Bruce; García, Nicolás; Iturriaga, Rodrigo

    2009-01-01

    Avocado (Persea americana Mill.) trees are among the most sensitive of fruit tree species to root hypoxia as a result of flooded or poorly drained soil. Similar to drought stress, an early physiological response to root hypoxia in avocado is a reduction of stomatal conductance. It has been previously determined in avocado trees that an extracellular electrical signal between the base of stem and leaves is produced and related to reductions in stomatal conductance in response to drought stress. The current study was designed to determine if changes in the extracellular electrical potential between the base of the stem and leaves in avocado trees could also be detected in response to short-term (min) or long-term (days) root hypoxia, and if these signals could be related to stomatal conductance (gs), root and leaf ABA and ACC concentrations, ethylene emission from leaves and leaf abscission. In contrast to previous observations for drought-stressed trees, short-term or long-term root hypoxia did not stimulate an electrical potential difference between the base of the stem and leaves. Short-term hypoxia did not result in a significant decrease in gs compared with plants in the control treatment, and no differences in ABA concentration were found between plants subjected to hypoxia and control plants. Long-term hypoxia in the root zone resulted in a significant decrease in gs, increased leaf ethylene and increased leaf abscission. The results indicate that for avocado trees exposed to root hypoxia, electrical signals do not appear to be the primary root-to-shoot communication mechanism involved in signaling for stomatal closure as a result of hypoxia in the root zone. PMID:19649181

  14. In vivo blockade of thalamic GABA(B) receptors increases excitatory amino-acid levels.

    PubMed

    Nyitrai, G; Emri, Z; Crunelli, V; Kékesi, K A; Dobolyi, A; Juhász, G

    1996-12-30

    The effect of intrathalamic application of GABA(B) receptor antagonists on the basal excitatory amino-acid levels was studied using microdialysis probes implanted in the dorsal lateral geniculate nucleus and in the ventrobasal complex. In both nuclei, continuous perfusion of the GABA(B) receptor antagonist 3-aminopropyl-(diethoxymethyl)-phosphinic acid (CGP 35348) produced an increase in the extracellular concentration of aspartate and (to a lesser extent) glutamate, but no change was observed in the level of taurine, the main amino acid involved in the regulation of brain osmolarity processes. In contrast, 3-amino-2-hydroxy-2-(4-chlorophenyl)-propanesulphonic acid (2-hydroxy-saclofen), another GABA(B) receptor antagonist, failed to affect the extracellular concentration of aspartate, glutamate and taurine. Thus, the basal level of excitatory amino acids in the thalamus in vivo is under the control of CGP 35348-sensitive GABA(B) receptors.

  15. Using "Clickers" in the Classroom to Increase the Level of Student Interaction

    DTIC Science & Technology

    2008-12-01

    Clickers” in the Classroom to Increase the Level of Student Interaction 6. AUTHOR( S ) Robert R. Prewitt and Katherine B. Oropeza 5. FUNDING NUMBERS...7. PERFORMING ORGANIZATION NAME( S ) AND ADDRESS(ES) Naval Postgraduate School Monterey, CA 93943-5000 8. PERFORMING ORGANIZATION REPORT NUMBER...9. SPONSORING /MONITORING AGENCY NAME( S ) AND ADDRESS(ES) N/A 10. SPONSORING/MONITORING AGENCY REPORT NUMBER 11. SUPPLEMENTARY NOTES The

  16. Increased level of H19 long noncoding RNA promotes invasion, angiogenesis, and stemness of glioblastoma cells.

    PubMed

    Jiang, Xiaochun; Yan, Yukui; Hu, Minghua; Chen, Xiande; Wang, Yaxian; Dai, Yi; Wu, Degang; Wang, Yongsheng; Zhuang, Zhixiang; Xia, Hongping

    2016-01-01

    OBJECT Increased levels of H19 long noncoding RNA (lncRNA) have been observed in many cancers, suggesting that overexpression of H19 may be important in the development of carcinogenesis. However, the role of H19 in human glioblastoma is still unclear. The object of this study was to examine the level of H19 in glioblastoma samples and investigate the role of H19 in glioblastoma carcinogenesis. METHODS Glioblastoma and nontumor brain tissue specimens were obtained from tissue obtained during tumor resection in 30 patients with glioblastoma. The level of H19 lncRNA was detected by real-time quantitative reverse transcription polymerase chain reaction. The role of H19 in invasion, angiogenesis, and stemness of glioblastoma cells was then investigated using commercially produced cell lines (U87 and U373). The effects of H19 overexpression on glioblastoma cell invasion and angiogenesis were detected by in vitro Matrigel invasion and endothelial tube formation assay. The effects of H19 on glioblastoma cell stemness and tumorigenicity were investigated by neurosphere formation and an in vivo murine xenograft model. RESULTS The authors found that H19 is significantly overexpressed in glioblastoma tissues, and the level of expression was associated with patient survival. In the subsequent investigations, the authors found that overexpression of H19 promotes glioblastoma cell invasion and angiogenesis in vitro. Interestingly, H19 was also significantly overexpressed in CD133(+) glioblastoma cells, and overexpression of H19 was associated with increased neurosphere formation of glioblastoma cells. Finally, stable overexpression of H19 was associated with increased tumor growth in the murine xenograft model. CONCLUSIONS The results of this study suggest that increased expression of H19 lncRNA promotes invasion, angiogenesis, stemness, and tumorigenicity of glioblastoma cells. Taken together, these findings indicate that H19 plays an important role in tumorigenicity and

  17. Masting promotes individual- and population-level reproduction by increasing pollination efficiency.

    PubMed

    Moreira, Xoaquín; Abdala-Roberts, Luis; Linhart, Yan B; Mooney, Kailen A

    2014-04-01

    Masting is a reproductive strategy defined as the intermittent and synchronized production of large seed crops by a plant population. The pollination efficiency hypothesis proposes that masting increases pollination success in plants. Despite its general appeal, no previous studies have used long-term data together with population- and individual-level analyses to assess pollination efficiency between mast and non-mast events. Here we rigorously tested the pollination efficiency hypothesis in ponderosa pine (Pinus ponderosa), a long-lived monoecious, wind-pollinated species, using a data set on 217 trees monitored annually for 20 years. Relative investment in male and female function by individual trees did not vary between mast and non-mast years. At both the population and individual level, the rate of production of mature female cones relative to male strobili production was higher in mast than non-mast years, consistent with the predicted benefit of reproductive synchrony on reproductive success. In addition, at the individual level we found a higher conversion of unfertilized female conelets into mature female cones during a mast year compared to a non-mast year. Collectively, parallel results at the population and individual tree level provide robust evidence for the ecological, and potentially also evolutionary, benefits of masting through increased pollination efficiency.

  18. Optogenetic Stimulation Increases Level of Antiapoptotic Protein Bcl-xL in Neurons.

    PubMed

    Lanshakov, D A; Drozd, U S; Dygalo, N N

    2017-03-01

    The antiapoptotic protein Bcl-xL is associated with several neuroplastic processes such as formation of synapses, regulation of spontaneous and evoked synaptic responses, and release of neurotransmitters. Dependence of expression on activity of neurons is characteristic for many proteins participating in regulation of neuroplasticity. Whether such property is exhibited by the Bcl-xL protein was analyzed using in vivo optogenetic stimulation of hippocampal glutamatergic neurons expressing channelrhodopsin ChR2H134 under CAMKIIa promoter in the adeno-associated viral vector, followed by immunohistochemical determination of the level of Bcl-xL protein in these neurons and surrounding cells. Increase in the level of early response c-Fos protein following illumination with blue light was indicative of activation of these hippocampal neurons. The optogenetic activation of hippocampus resulted in a significant increase in the level of antiapoptotic protein Bcl-xL in the photosensitive neurons as well as in the surrounding cells. The dependence of the level of expression of Bcl-xL protein on the activity of neurons indicates that this protein possesses one more important property that is essential for participation in neuroplastic processes in the brain.

  19. Increase in levels of cyclic AMP during avian limb chondrogenesis in vitro.

    PubMed

    Solursh, M; Reiter, R; Ahrens, P B; Pratt, R M

    1979-01-01

    In the present study the level of cAMP was measured during in vitro chondrogenesis of wing mesenchyme of stage 24 chick embryos and was found to increase significantly from 6.3 pmol/mg protein at the end of the first day of culture to 9.7 pmol/mg protein on the second day, when chondrogenic expression is first detected by the appearance of an Alcian blue staining extracellular matrix. Nonchondrogenic cultures derived from wings of stage 19 embryos had a lower level of cAMP (4.4 +/- 0.07 pmol/mg protein). The level of cAMP in intact wings was 4.5 +/- 0.4 pmol/mg protein and did not change between stages 19 through 25. The correlatin between increased levels of cAMP and the onset of chondrogenesis is consistent with a role of cAMP in the expression of differentiated functions in chondrocytes, as well as in some other cell types.

  20. Increased fibrinogen levels at diagnosis are associated with adverse outcome in patients with acute myeloid leukemia.

    PubMed

    Berger, Martin D; Heini, Alexander D; Seipel, Katja; Mueller, Beatrice; Angelillo-Scherrer, Anne; Pabst, Thomas

    2016-06-15

    Increased plasma fibrinogen levels are associated with shortened overall survival (OS) in some solid tumor types. In contrast, the prognostic significance of varying fibrinogen levels in acute myeloid leukemia (AML) at diagnosis is unknown. In this study, we assessed the prognostic significance of fibrinogen levels in AML patients. In a comprehensive retrospective single-center study, we determined the survival rates of 375 consecutive AML patients undergoing at least one cycle of intensive chemotherapy induction treatment. Patients were dichotomized between low (<4.1 g/L) and high fibrinogen levels (≥4.1 g/L) at diagnosis of AML before initiation of treatment. Subsequently, quartile ranges were applied to analyze the association of varying fibrinogen levels on survival. We observed that the rates of complete remission, early death, and admission to intensive care unit were equal in the low versus high fibrinogen group. However, OS was significantly better in the low fibrinogen group (27.3 vs 13.5 months; p = 0.0009) as well as progression-free survival (12.3 vs 7.8 months; p = 0.0076). This survival difference remained significant in the multivariate analysis (p = 0.003). Assessing quartiles of fibrinogen values, we further confirmed this observation. Our data suggest that high fibrinogen levels at diagnosis of AML are associated with unfavorable OS and progression-free survival but not with increased mortality during induction treatment. Copyright © 2016 John Wiley & Sons, Ltd.

  1. Residential Proximity to Major Roadways is Associated with Increased Levels of AC133+ Circulating Angiogenic Cells

    PubMed Central

    DeJarnett, Natasha; Yeager, Ray; Conklin, Daniel J.; Lee, Jongmin; O'Toole, Timothy E.; McCracken, James; Abplanalp, Wes; Srivastava, Sanjay; Riggs, Daniel W.; Hamzeh, Ihab; Wagner, Stephen; Chugh, Atul; DeFilippis, Andrew; Ciszewski, Tiffany; Wyatt, Brad; Becher, Carrie; Higdon, Deirdre; Ramos, Kenneth S.; Tollerud, David J.; Myers, John A.; Rai, Shesh N.; Shah, Jasmit; Zafar, Nagma; Krishnasamy, Sathya S.; Prabhu, Sumanth D.; Bhatnagar, Aruni

    2016-01-01

    Objective Previous studies have shown that residential proximity to a roadway is associated with increased cardiovascular disease (CVD) risk. Yet the nature of this association remains unclear, and its impact on individual CVD risk factors has not been assessed. The objective of this study was to determine whether residential proximity to roadways influences systemic inflammation and the levels of circulating angiogenic cells. Approach and Results In a cross-sectional study, CVD risk factors, blood levels of C-reactive protein (CRP), and 15 antigenically-defined circulating angiogenic cell populations were measured in participants (n=316) with moderate to high CVD risk. Attributes of roadways surrounding residential locations were assessed using Geographic Information Systems. Associations between road proximity and cardiovascular indices were analyzed using Generalized Linear Models. Close proximity (<50m) to a major roadway was associated with lower income and higher rates of smoking, but not CRP levels. After adjustment for potential confounders, levels of circulating angiogenic cell in peripheral blood were significantly elevated in people living in close proximity to a major roadway (CD31+/AC133+, AC133+, CD34+/AC133+, and CD34+/45dim/AC133+ cells); and positively associated with road segment distance (CD31+/AC133+, AC133+, and CD34+/AC133+ cells), traffic intensity (CD31+/AC133+ and AC133+ cells), and distance-weighted traffic intensity (CD31+/34+/45+/AC133+ cells). Conclusions Living close to a major roadway is associated with elevated levels of circulating cells positive for the “early” stem marker, AC133+. This may reflect an increased need for vascular repair. Levels of these cells in peripheral blood may be a sensitive index of cardiovascular injury due to residential proximity to roadways. PMID:26293462

  2. Paternal retrievals increase testosterone levels in both male and female California mouse (Peromyscus californicus) offspring.

    PubMed

    Chary, Mamatha C; Cruz, Jayson P; Bardi, Massimo; Becker, Elizabeth A

    2015-07-01

    The importance of maternal care on offspring development has received considerable attention, although more recently, researchers have begun to focus on the significance of paternal contributions. In the monogamous and bi-parental California mouse, fathers provide high levels of care, and therefore serve as a model system for studying paternal effects on behavior and underlying neuroendocrine mechanisms. Paternal retrievals in this species influence long term changes in brain (expression of arginine vasopressin-AVP) and behavior (aggression and parenting) in adult male offspring. Further, paternal retrievals induce a transient increase in testosterone (T) in male offspring, which is thought to mediate the relationship between paternal retrievals and AVP expression. Although the father-son relationship has been well characterized, few studies have examined father-daughter interactions. In California mice, paternal retrievals increase aggression in female offspring. Although T has been implicated in the regulation of female aggression, it remains unclear whether T may underlie long-term changes in female offspring aggression in response to paternal retrievals. In the current study, we examined the influence of paternal retrievals on T in both male and female offspring. Retrievals were manipulated experimentally by displacement of the pup and trunk blood was collected from retrieved, non-retrieved, and non-manipulated (baseline) pups. We found that fathers expressed similar levels of retrievals towards sons and daughters, and that T levels were elevated in retrieved, as compared to non-retrieved offspring. Similar to what has been previously described in male offspring and replicated here, female offspring that were retrieved had higher T levels than non-retrieved females. Neither females nor males experienced a change in corticosterone levels in response to retrievals suggesting offspring do not mount a stress response to paternal care. Therefore, our data suggest

  3. Rapid changes in leaf elongation, ABA and water status during the recovery phase following application of water stress in two durum wheat varieties differing in drought tolerance.

    PubMed

    Mahdid, Mohamed; Kameli, Abdelkrim; Ehlert, Christina; Simonneau, Thierry

    2011-10-01

    This study aims to investigate the role of Abscisic acid (ABA) in water potential and turgor variations as well as growth recovery during the first phase of a rapid water stress induced by PEG6000. Two wheat varieties (Triticum durum L.), MBB (more tolerant) and OZ (less productive under drought), were grown in aerated nutrient solutions. Leaf elongation kinetics of the growing leaf 3 was estimated using LVDT. Water potential was measured using a pressure chamber; osmotic potential was estimated from expressed sap of elongation zone, turgor pressure of the same zone of leaf three was estimated directly by pressure probe. Growth rapidly ceased for a period of about one hour after the addition of PEG, gradual recovery was then observed for about 2 h. A significant difference was found in the % recovery of Leaf Elongation Rate (LER) and ABA between the two varieties, leading to better water status in MBB compared to OZ. The results of this study showed the possible role of ABA on growth resumption by the increase of relative water content and turgor via osmotic adjustment during the stress period in the leaves, which indicates the importance of OA in the resumption of LER even in the short term under conditions of water deficit. Full recovery of turgor but not of LER at the end stress period suggested the possible effect on cell wall extensibility (hardening) even at short term resulting from the rapid accumulation of ABA.

  4. Comparing Canadian and American cybersecurity awareness levels: Educational strategies to increase public awareness

    NASA Astrophysics Data System (ADS)

    Hoggard, Amy

    Cybersecurity awareness is an important issue that affects everyone who uses a computer or a mobile device. Canada and the United States both recognize the value of mitigating cybersecurity risks in terms of national safety, economic stability and protection of their citizens. The research performed compared the levels of cybersecurity awareness in Canadian and American Internet users. Canadian and American users were equally aware of cybersecurity measures, but were not implementing best practices to keep themselves safe. The research suggested users needed to understand why a cybersecurity measure was important before being motivated to implement it. Educational strategies were reviewed in both Canada and the United States and it was determined that although there were significant resources available, they were not being utilized by both the educators and the public. In order to increase cybersecurity awareness levels, nations should focus on increasing the public's awareness by using various types of messaging, such as cartoons, in media. One possible consideration is a compulsory awareness model before accessing the Internet. Cybersecurity topics should be included in the curriculum for students at all levels of education and a focus on providing training and resources to teachers will help increase the cybersecurity knowledge of children and youth.

  5. Pesticide exposure in honey bees results in increased levels of the gut pathogen Nosema.

    PubMed

    Pettis, Jeffery S; vanEngelsdorp, Dennis; Johnson, Josephine; Dively, Galen

    2012-02-01

    Global pollinator declines have been attributed to habitat destruction, pesticide use, and climate change or some combination of these factors, and managed honey bees, Apis mellifera, are part of worldwide pollinator declines. Here we exposed honey bee colonies during three brood generations to sub-lethal doses of a widely used pesticide, imidacloprid, and then subsequently challenged newly emerged bees with the gut parasite, Nosema spp. The pesticide dosages used were below levels demonstrated to cause effects on longevity or foraging in adult honey bees. Nosema infections increased significantly in the bees from pesticide-treated hives when compared to bees from control hives demonstrating an indirect effect of pesticides on pathogen growth in honey bees. We clearly demonstrate an increase in pathogen growth within individual bees reared in colonies exposed to one of the most widely used pesticides worldwide, imidacloprid, at below levels considered harmful to bees. The finding that individual bees with undetectable levels of the target pesticide, after being reared in a sub-lethal pesticide environment within the colony, had higher Nosema is significant. Interactions between pesticides and pathogens could be a major contributor to increased mortality of honey bee colonies, including colony collapse disorder, and other pollinator declines worldwide.

  6. Pesticide exposure in honey bees results in increased levels of the gut pathogen Nosema

    NASA Astrophysics Data System (ADS)

    Pettis, Jeffery S.; Vanengelsdorp, Dennis; Johnson, Josephine; Dively, Galen

    2012-02-01

    Global pollinator declines have been attributed to habitat destruction, pesticide use, and climate change or some combination of these factors, and managed honey bees, Apis mellifera, are part of worldwide pollinator declines. Here we exposed honey bee colonies during three brood generations to sub-lethal doses of a widely used pesticide, imidacloprid, and then subsequently challenged newly emerged bees with the gut parasite, Nosema spp. The pesticide dosages used were below levels demonstrated to cause effects on longevity or foraging in adult honey bees. Nosema infections increased significantly in the bees from pesticide-treated hives when compared to bees from control hives demonstrating an indirect effect of pesticides on pathogen growth in honey bees. We clearly demonstrate an increase in pathogen growth within individual bees reared in colonies exposed to one of the most widely used pesticides worldwide, imidacloprid, at below levels considered harmful to bees. The finding that individual bees with undetectable levels of the target pesticide, after being reared in a sub-lethal pesticide environment within the colony, had higher Nosema is significant. Interactions between pesticides and pathogens could be a major contributor to increased mortality of honey bee colonies, including colony collapse disorder, and other pollinator declines worldwide.

  7. The evaluation of increase in hemodialysis frequency on C-reactive protein levels and nutritional status.

    PubMed

    Rashidi, Ali Akbar; Soleimani, Ali Reza; Nikoueinejad, Hassan; Sarbolouki, Shokooh

    2013-03-16

    Malnutrition and inflammation are the most important causes of cardiovascular disease in hemodialysis patients. This study was conducted to evaluate the effect of increase in hemodialysis frequency on C-reactive protein (CRP) level and nutritional markers in contrast to previous routine method. 18 hemodialysis patients with a mean age of 53±16 years were randomly selected in this before-and-after clinical trial. The patients under a standard hemodialysis of 3 times/4 h per week were converted to 4 times/4 h for a period of 6 weeks. The CRP, albumin, triglyceride, total cholesterol, LDL, HDL serum levels, anthropometric indices and 24-h diet recall intake was assessed before and after of the period. The data were analyzed using paired t-test, and P-value less than 0.05 was considered significant. All patients completed the study. Mean weight, body mass index and serum albumin increased while serum CRP level decreased significantly after the intervention (P<0.03). Triglyceride, total cholesterol, LDL, HDL, as well as energy, protein and fat intake had no significant change before and after the study. Increase in dialysis frequency decreased systemic inflammation and improved the nutritional state of hemodialysis patients. Therefore, it may decrease the risk of cardiovascular events in these patients.

  8. 40 CFR 63.1297 - Standards for slabstock flexible polyurethane foam production-HAP ABA emissions from the...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... polyurethane foam production-HAP ABA emissions from the production line. 63.1297 Section 63.1297 Protection of... foam production—HAP ABA emissions from the production line. (a) Each owner or operator of a new or... § 63.1293(a)(1) shall control HAP ABA emissions from the slabstock polyurethane foam production line...

  9. Increased acetyl and total histone levels in post-mortem Alzheimer's disease brain.

    PubMed

    Narayan, Pritika J; Lill, Claire; Faull, Richard; Curtis, Maurice A; Dragunow, Mike

    2015-02-01

    Histone acetylation is an epigenetic modification that plays a critical role in chromatin remodelling and transcriptional regulation. There is increasing evidence that epigenetic modifications may become compromised in aging and increase susceptibility to the development of neurodegenerative disorders such as Alzheimer's disease. Immunohistochemical labelling of free-floating sections from the inferior temporal gyrus (Alzheimer's disease, n=14; control, n=17) and paraffin-embedded tissue microarrays containing tissue from the middle temporal gyrus (Alzheimer's disease, n=29; control, n=28) demonstrated that acetyl histone H3 and acetyl histone H4 levels, as well as total histone H3 and total histone H4 protein levels, were significantly increased in post-mortem Alzheimer's disease brain tissue compared to age- and sex-matched neurologically normal control brain tissue. Changes in acetyl histone levels were proportional to changes in total histone levels. The increase in acetyl histone H3 and H4 was observed in Neuronal N immunopositive pyramidal neurons in Alzheimer's disease brain. Using immunolabelling, histone markers correlated significantly with the level of glial fibrillary acidic protein and HLA-DP, -DQ and -DR immunopositive cells and with the pathological hallmarks of Alzheimer's disease (hyperphosphorylated tau load and β-amyloid plaques). Given that histone acetylation changes were correlated with changes in total histone protein, it was important to evaluate if protein degradation pathways may be compromised in Alzheimer's disease. Consequently, significant positive correlations were also found between ubiquitin load and histone modifications. The relationship between histone acetylation and ubiquitin levels was further investigated in an in vitro model of SK-N-SH cells treated with the proteasome inhibitor Mg132 and the histone deacetylase inhibitor valproic acid. In this model, compromised protein degradation caused by Mg132 lead to elevated histone

  10. The loudness of sounds that increase and decrease continuously in level.

    PubMed

    Canévet, G; Scharf, B

    1990-11-01

    A sound at a low level is heard as much softer after having decreased continuously from higher levels than if presented after a period of silence at that same low level. Canévet [Acustica 61, 256-264 (1986)] demonstrated this phenomenon for a tone that (1) decreased from 65 to 20 dB in 180 s; he also presented a tone that (2) increased from 20 dB, or (3) was presented as pairs of bursts at various levels in random order. Below about 40 dB, loudness changed most rapidly in the decreasing condition so that, at 20 dB, the tone was judged ten times softer than in conditions (2) and (3). In the present experiments, magnitude estimation was used to examine the possible role of judgmental biases and adaptation in this rapid loudness decline, which we call decruitment. Results show that decruitment did not come about because subjects made many successive loudness judgments; loudness declined as much when a tone was judged only twice, at the beginning and end of its 180-s decrease. In contrast, interrupting the decreasing tone so that it was heard only at 70 dB and 160 s later at 30 dB greatly diminished the decruitment. Similarly, pairs of 500-ms tone bursts presented at successively lower levels instead of continously decreasing did not show decruitment, suggesting that sequential biases are irrelevant. The likely cause of decruitment is sensory adaptation.

  11. Resilience to traumatic events related to urban violence and increased IL10 serum levels.

    PubMed

    Teche, Stefania P; Rovaris, Diego L; Aguiar, Bianca W; Hauck, Simone; Vitola, Eduardo S; Bau, Claiton H D; Freitas, Lucia H; Grevet, Eugenio H

    2017-04-01

    The exposition to traumatic events related to urban violence is epidemic in Brazil, with rate of 80% in the general population, and is becoming a major cause of post-traumatic stress disorder (PTSD). The objective of the study was to compare serum levels of pro-inflammatory interleukin-6 (IL-6) and anti-inflammatory interleukin-10 (IL-10) in PTSD and resilient individuals. We hypothesized that resilient individuals present an attenuated pro-inflammatory and enhanced anti-inflammatory state. We conducted a case-control study comparing 30 resilient individuals and 30 PTSD patients exposed to traumatic events related to urban violence. The groups were evaluated using Self-Report Questionnaire (SRQ-20), Mini-International Neuropsychiatric Interview (MINI) and the Davidson Trauma Scale. For all individuals, blood samples were collected to determine IL-6, IL-10 and cortisol serum levels. All samples were frozen at -80°C until the assay and were analyzed with the same immunoassay kit and in duplicates. The resilient group presented higher IL-10 levels than PTSD patients [mean (CI95%); 1.03 (0.52-2.08) pg/mL vs. 0.29 (0.20-0.43) pg/mL; P=0.002]. There were no differences in terms of IL-6 or cortisol levels. The results provided evidence for increased levels of IL-10 in resilient individuals when compared to PTSD patients, probably conferring them a better anti-inflammatory response after exposition.

  12. A translocation causing increased alpha-klotho level results in hypophosphatemic rickets and hyperparathyroidism.

    PubMed

    Brownstein, Catherine A; Adler, Felix; Nelson-Williams, Carol; Iijima, Junko; Li, Peining; Imura, Akihiro; Nabeshima, Yo-Ichi; Reyes-Mugica, Miguel; Carpenter, Thomas O; Lifton, Richard P

    2008-03-04

    Phosphate homeostasis is central to diverse physiologic processes including energy homeostasis, formation of lipid bilayers, and bone formation. Reduced phosphate levels due to excessive renal loss cause hypophosphatemic rickets, a disease characterized by prominent bone defects; conversely, hyperphosphatemia, a major complication of renal failure, is accompanied by parathyroid hyperplasia, hyperparathyroidism, and osteodystrophy. Here, we define a syndrome featuring both hypophosphatemic rickets and hyperparathyroidism due to parathyroid hyperplasia as well as other skeletal abnormalities. We show that this disease is due to a de novo translocation with a breakpoint adjacent to alpha-Klotho, which encodes a beta-glucuronidase, and is implicated in aging and regulation of FGF signaling. Plasma alpha-Klotho levels and beta-glucuronidase activity are markedly increased in the affected patient; unexpectedly, the circulating FGF23 level is also markedly elevated. These findings suggest that the elevated alpha-Klotho level mimics aspects of the normal response to hyperphosphatemia and implicate alpha-Klotho in the selective regulation of phosphate levels and in the regulation of parathyroid mass and function; they also have implications for the pathogenesis and treatment of renal osteodystrophy in patients with kidney failure.

  13. Potential population-level effects of increased haulout-related mortality of Pacific walrus calves

    USGS Publications Warehouse

    Udevitz, Mark S.; Taylor, Rebecca L.; Garlich-Miller, Joel L.; Quakenbush, Lori T.; Snyder, Jonathan A.

    2013-01-01

    Availability of summer sea ice has been decreasing in the Chukchi Sea during recent decades, and increasing numbers of Pacific walruses have begun using coastal haulouts in late summer during years when sea ice retreats beyond the continental shelf. Calves and yearlings are particularly susceptible to being crushed during disturbance events that cause the herd to panic and stampede at these large haulouts, but the potential population-level effects of this mortality are unknown. We used recent harvest data, along with previous assumptions about demographic parameters for this population, to estimate female population size and structure in 2009 and project these numbers forward using a range of assumptions about future harvests and haulout-related mortality that might result from increased use of coastal haulouts during late summer. We found that if demographic parameters were held constant, the levels of harvest that occurred during 1990–2008 would have allowed the population to grow during that period. Our projections indicate, however, that an increase in haulout-related mortality affecting only calves has a greater effect on the population than an equivalent increase in harvest-related mortality distributed among all age classes. Therefore, disturbance-related mortality of calves at coastal haulouts may have relatively important population consequences.

  14. Increased CRP levels may be a trait marker of suicidal attempt.

    PubMed

    Courtet, Ph; Jaussent, I; Genty, C; Dupuy, A M; Guillaume, S; Ducasse, D; Olié, E

    2015-10-01

    Suicide is a leading cause of death worldwide. Identifying biomarkers will help enhance our understanding of suicidal pathophysiology and improve its prevention. Therefore, we investigated CRP levels in 600 depressed inpatients: 520 patients had a lifetime history of suicide attempts and 80 patients did not have any history of suicide attempts. For all patients, we assessed socio-demographic features, lifetime Axis I DSM-IV diagnoses, depression intensity, suicidal ideation, characteristics of suicidal history, and history of childhood trauma. The day following admission, fasting blood tests yielded samples collected for the measurement of high sensitivity hs-CRP. CRP levels were associated with a history of suicide attempts. The risk of suicide attempts increased with higher levels of CRP in a dose-response way before and after adjustments for age, gender, chronic diseases, addiction and anxiety comorbidities, antidepressants use, smoking status and sexual abuse. Noteworthy, the association between CRP levels and history of suicide attempts remained significant after having excluded patients with chronic diseases. There was no significant difference in CRP levels between patients who attempted suicide more or less than a week before plasma sampling, and no significant difference in CRP levels was evidenced between high vs low suicidal ideation. In conclusion, this is the first study suggesting that CRP may be a trait marker for suicidal vulnerability by associating CRP levels and a lifetime history of suicide attempts in depressed inpatients. Therefore, determining the inflammatory marker profile of individuals exhibiting suicidal behaviors could be relevant for anticipating behaviors and refining new therapeutic opportunities.

  15. Ocean acidification increases the accumulation of toxic phenolic compounds across trophic levels

    NASA Astrophysics Data System (ADS)

    Jin, Peng; Wang, Tifeng; Liu, Nana; Dupont, Sam; Beardall, John; Boyd, Philip W.; Riebesell, Ulf; Gao, Kunshan

    2015-10-01

    Increasing atmospheric CO2 concentrations are causing ocean acidification (OA), altering carbonate chemistry with consequences for marine organisms. Here we show that OA increases by 46-212% the production of phenolic compounds in phytoplankton grown under the elevated CO2 concentrations projected for the end of this century, compared with the ambient CO2 level. At the same time, mitochondrial respiration rate is enhanced under elevated CO2 concentrations by 130-160% in a single species or mixed phytoplankton assemblage. When fed with phytoplankton cells grown under OA, zooplankton assemblages have significantly higher phenolic compound content, by about 28-48%. The functional consequences of the increased accumulation of toxic phenolic compounds in primary and secondary producers have the potential to have profound consequences for marine ecosystem and seafood quality, with the possibility that fishery industries could be influenced as a result of progressive ocean changes.

  16. Ocean acidification increases the accumulation of toxic phenolic compounds across trophic levels.

    PubMed

    Jin, Peng; Wang, Tifeng; Liu, Nana; Dupont, Sam; Beardall, John; Boyd, Philip W; Riebesell, Ulf; Gao, Kunshan

    2015-10-27

    Increasing atmospheric CO2 concentrations are causing ocean acidification (OA), altering carbonate chemistry with consequences for marine organisms. Here we show that OA increases by 46-212% the production of phenolic compounds in phytoplankton grown under the elevated CO2 concentrations projected for the end of this century, compared with the ambient CO2 level. At the same time, mitochondrial respiration rate is enhanced under elevated CO2 concentrations by 130-160% in a single species or mixed phytoplankton assemblage. When fed with phytoplankton cells grown under OA, zooplankton assemblages have significantly higher phenolic compound content, by about 28-48%. The functional consequences of the increased accumulation of toxic phenolic compounds in primary and secondary producers have the potential to have profound consequences for marine ecosystem and seafood quality, with the possibility that fishery industries could be influenced as a result of progressive ocean changes.

  17. Sea-level Rise Increases the Frequency of Nuisance Flooding in Coastal Regions

    NASA Astrophysics Data System (ADS)

    Moftakhari Rostamkhani, H.; Aghakouchak, A.; Sanders, B. F.; Feldman, D.; Sweet, W.; Matthew, R.; Luke, A.

    2015-12-01

    The global warming-drivensea-level rise (SLR) posesa serious threat for population and assets in flood-prone coastal zones over the next century. The rate of SLR is accelerated in recent decades and is expected to increase based on current trajectories of anthropogenic activities and greenhouse gas emissions. Over the 20th century, an increase in the frequency of nuisance (minor) flooding has been reported due to the reduced gap between tidal datum and flood stage. Nuisance flooding (NF), however non-destructive, causes public inconvenience, business interruption, and substantial economic losses due to impacts such as road closures and degradation of infrastructure. It also portends an increased risk in severe floods. Here we report substantial increases in NF along the coasts of United States due to SLR over the past decades. We then take the projected SLR under the least and the most extreme representative concentration pathways (e.gRCP2.6 and RCP 8.5) to estimate the increase in NF in the near- (2030) and mid-term (2050) future. The results suggest that projected SLR will cause up to two-fold more frequent NF by 2050, compared with the 20th century. The projected increase in NF will have significant socio-economic impacts and pose public health risks especially in rapidly urbanized coastal regions.

  18. Transgenic Arabidopsis thaliana containing increased levels of ATP and sucrose is more susceptible to Pseudomonas syringae.

    PubMed

    Zhang, Renshan; Qi, Hua; Sun, Yuzhe; Xiao, Shi; Lim, Boon Leong

    2017-01-01

    Disease resistance exerts a fitness cost on plants, presumably due to the extra consumption of energy and carbon. In this study, we examined whether transgenic Arabidopsis thaliana with increased levels of ATP and sucrose is more resistant or susceptible to pathogen infection. Lines of A. thaliana over-expressing purple acid phosphatase 2 (AtPAP2) (OE lines) contain increased levels of ATP and sucrose, with improved growth rate and seed production. Compared to wild type (WT) and pap2 lines, the OE lines were more susceptible to several Pseudomonas syringae pv. tomato (Pst) strains carrying AvrRpm1, AvrRpt2 AvrRps4, AvrPtoB, HrcC and WT strain DC3000. The increased susceptibility of the OE lines to Pst strains cannot solely be attributed to the suppressed expression of R-genes but must also be attributed to the suppression of downstream signaling components, such as MOS2, EDS1 and EDS5. Before infection, the levels of salicylic acid (SA) and jasmonic acid (JA) precursor OPDA were similar in the leaves of OE, pap2 and WT plants, whereas the levels of JA and its derivative JA-Ile were significantly lower in the leaves of OE lines and higher in the pap2 line. The expression of JA marker defense gene PDF1.2 was up-regulated in the OE lines compared to the WT prior to Pst DC3000 infection, but its expression was lower in the OE lines after infection. In summary, high fitness Arabidopsis thaliana exhibited altered JA metabolism and broad suppression of R-genes and downstream genes as well as a higher susceptibility to Pst infections.

  19. Transgenic Arabidopsis thaliana containing increased levels of ATP and sucrose is more susceptible to Pseudomonas syringae

    PubMed Central

    Zhang, Renshan; Qi, Hua; Sun, Yuzhe; Xiao, Shi

    2017-01-01

    Disease resistance exerts a fitness cost on plants, presumably due to the extra consumption of energy and carbon. In this study, we examined whether transgenic Arabidopsis thaliana with increased levels of ATP and sucrose is more resistant or susceptible to pathogen infection. Lines of A. thaliana over-expressing purple acid phosphatase 2 (AtPAP2) (OE lines) contain increased levels of ATP and sucrose, with improved growth rate and seed production. Compared to wild type (WT) and pap2 lines, the OE lines were more susceptible to several Pseudomonas syringae pv. tomato (Pst) strains carrying AvrRpm1, AvrRpt2 AvrRps4, AvrPtoB, HrcC and WT strain DC3000. The increased susceptibility of the OE lines to Pst strains cannot solely be attributed to the suppressed expression of R-genes but must also be attributed to the suppression of downstream signaling components, such as MOS2, EDS1 and EDS5. Before infection, the levels of salicylic acid (SA) and jasmonic acid (JA) precursor OPDA were similar in the leaves of OE, pap2 and WT plants, whereas the levels of JA and its derivative JA-Ile were significantly lower in the leaves of OE lines and higher in the pap2 line. The expression of JA marker defense gene PDF1.2 was up-regulated in the OE lines compared to the WT prior to Pst DC3000 infection, but its expression was lower in the OE lines after infection. In summary, high fitness Arabidopsis thaliana exhibited altered JA metabolism and broad suppression of R-genes and downstream genes as well as a higher susceptibility to Pst infections. PMID:28152090

  20. The Benefits of Increased Sensation Level and Bandwidth for Spatial Release From Masking

    PubMed Central

    Kampel, Sean D.; Gordon, Samuel Y.; Gallun, Frederick J.

    2017-01-01

    Objective: Spatial release from masking (SRM) can increase speech intelligibility in complex listening environments. The goal of the present study was to document how speech-in-speech stimuli could be best processed to encourage optimum SRM for listeners who represent a range of ages and amounts of hearing loss. We examined the effects of equating stimulus audibility among listeners, presenting stimuli at uniform sensation levels (SLs), and filtering stimuli at two separate bandwidths. Design: Seventy-one participants completed two speech intelligibility experiments (36 listeners in experiment 1; all 71 in experiment 2) in which a target phrase from the coordinate response measure (CRM) and two masking phrases from the CRM were presented simultaneously via earphones using a virtual spatial array, such that the target sentence was always at 0 degree azimuth angle and the maskers were either colocated or positioned at ±45 degrees. Experiments 1 and 2 examined the impacts of SL, age, and hearing loss on SRM. Experiment 2 also assessed the effects of stimulus bandwidth on SRM. Results: Overall, listeners’ ability to achieve SRM improved with increased SL. Younger listeners with less hearing loss achieved more SRM than older or hearing-impaired listeners. It was hypothesized that SL and bandwidth would result in dissociable effects on SRM. However, acoustical analysis revealed that effective audible bandwidth, defined as the highest frequency at which the stimulus was audible at both ears, was the best predictor of performance. Thus, increasing SL seemed to improve SRM by increasing the effective bandwidth rather than increasing the level of already audible components. Conclusions: Performance for all listeners, regardless of age or hearing loss, improved with an increase in overall SL and/or bandwidth, but the improvement was small relative to the benefits of spatial separation. PMID:27556520

  1. TBT-induced imposex in marine neogastropods is mediated by an increasing androgen level

    NASA Astrophysics Data System (ADS)

    Bettin, C.; Oehlmann, J.; Stroben, E.

    1996-09-01

    Tributyltin (TBT) exposure at different concentrations (5, 60, and 100 ng TBT as Sn/l) induces a concentration- and time-dependent imposex (=pseudohermaphroditism) development in female Nucella lapillus and Hinia reticulata. In both species the average imposex stage, termed as vas deferens sequence (VDS) index, and the average female penis length increases with increasing TBT concentration and duration of TBT exposure. Testosterone added at a concentration of 500 ng/l induces a faster and more intensive imposex development compared to that induced by the TBT concentrations used in the present experiments. Radioimmunological determination of endogenous steroid content reveals increasing testosterone titres in female gastropods exposed to TBT which correlate with the TBT concentration used and the duration of the experiment. The most marked and highest increase of the endogenous testosterone level is exhibited by females, of both species exposed to testosterone. Simulataneous exposure to TBT and to the antiandrogen cyproterone acetate which suppresses imposex development completely in N. lapillus and reduces imposex development strongly in H. reticulata proves that the imposex-inducing effects of TBT are mediated by an increasing androgen level and are not caused directly by the organotin compound itself. Further-more, TBT-induced imposex development can be suppressed in both snails by adding estrogens to the aqueous medium. These observations suggest that TBT causes an inhibition of the cytochrome P-450 dependent aromatase system which catalyses the aromatization of androgens to estrogens. The increase of the androgen content or the shift of the androgen-estrogen balance in favour of androgens induces the development of pseudohermaphroditism in marine prosobranchs. Artificial inhibition of the cytochrome P-450 dependent aromatase system using SH 489 (1-methyl-1,4-androstadiene-3,17-dione) as a steroidal aromatase inhibitor and flavone as a nonsteroidal aromatase

  2. Increased Lactate Levels and Reduced pH in Postmortem Brains of Schizophrenics: Medication Confounds

    PubMed Central

    Halim, Nader D.; Lipska, Barbara K.; Hyde, Thomas M.; Deep-Soboslay, Amy; Saylor, E. Michael; Herman, Mary; Thakar, Jay; Verma, Ajay; Kleinman, Joel E.

    2008-01-01

    A number of postmortem studies have found decreased pH in brains of patients with schizophrenia. Insofar as lower pH has been associated with decreased mRNA expression in postmortem human brain, decreased pH in schizophrenia may represent an important potential confound in comparisons between patients and controls. We hypothesized that decreased pH may be related to increased concentration of lactic acid. However, in contrast to the previous notion that an increase in lactic acid represents evidence for primary metabolic abnormalities in schizophrenia, we hypothesized that this increase is secondary to prior antipsychotic treatment. We have tested this by first demonstrating that lactate levels in the cerebellum of patients with schizophrenia (n=35) are increased relative to control subjects (n=42) by 28%, p=0.001. Second, we have shown that there is an excellent correlation between lactate levels in the cerebellum and pH, and that this correlation is particularly strong in patients (r=− 0.78, p=3e-6). Third, we have shown in rats that chronic haloperidol (0.8 mg/kg/day) and clozapine (5 mg/kg/day) increase lactic acid concentration in the frontal cortex relative to vehicle (by 31% and 22% respectively, p<0.01). These data suggest that lactate increases in postmortem human brain of patients with schizophrenia are associated with decreased pH and that these changes are possibly related to antipsychotic treatment rather than a primary metabolic abnormality in the prefrontal cortex of patients with schizophrenia. PMID:18177946

  3. Increased soluble GPVI levels in cirrhosis: evidence for early in vivo platelet activation.

    PubMed

    Egan, Karl; Dillon, Audrey; Dunne, Eimear; Kevane, Barry; Galvin, Zita; Maguire, Patricia; Kenny, Dermot; Stewart, Stephen; Ainle, Fionnuala Ni

    2017-01-01

    Cirrhosis is a consequence of prolonged liver injury and is characterised by extensive tissue fibrosis: the deposition of collagen-rich extracellular matrix. The haemostatic balance is disordered in cirrhosis and coagulation activation appears to promote fibrosis. In spite of recent studies demonstrating a role for anticoagulant therapy in preventing cirrhosis progression, there has not been a change in clinical practice, suggesting that physicians are reluctant to anticoagulate patients with cirrhosis due to bleeding risks. Platelets play an important role in facilitating coagulation. Glycoprotein VI (GPVI) is a platelet-specific collagen receptor that is shed from the platelet surface in a metalloproteinase-dependent manner in response to GPVI ligation and coagulation activation. Our aim was to use soluble GPVI levels to determine whether there was evidence for collagen and coagulation-induced platelet activation in early, well-compensated cirrhosis. Plasma soluble GPVI levels were quantified in 46 patients with mixed aetiology cirrhosis and 55 healthy controls using an immunoassay. In the cirrhosis group, soluble GPVI levels were significantly increased (5.8 ± 4.4 ng/ml, n = 46) compared to healthy controls (3.3 ± 3.4 ng/ml, n = 55, p < 0.05). This increase in soluble GPVI levels was still evident when levels were adjusted for platelet count (Healthy controls; 0.015 ± 0.018 ng/10(6) platelets/ml vs. cirrhosis; 0.048 ± 0.04 ng/10(6) platelets/ml, p < 0.0001). This study provides evidence for early platelet activation in patients with well-compensated cirrhosis. This may have translational implications for prognosis, treatment, and risk stratification.

  4. Increasing phylogenetic resolution at low taxonomic levels using massively parallel sequencing of chloroplast genomes

    PubMed Central

    2009-01-01

    Background Molecular evolutionary studies share the common goal of elucidating historical relationships, and the common challenge of adequately sampling taxa and characters. Particularly at low taxonomic levels, recent divergence, rapid radiations, and conservative genome evolution yield limited sequence variation, and dense taxon sampling is often desirable. Recent advances in massively parallel sequencing make it possible to rapidly obtain large amounts of sequence data, and multiplexing makes extensive sampling of megabase sequences feasible. Is it possible to efficiently apply massively parallel sequencing to increase phylogenetic resolution at low taxonomic levels? Results We reconstruct the infrageneric phylogeny of Pinus from 37 nearly-complete chloroplast genomes (average 109 kilobases each of an approximately 120 kilobase genome) generated using multiplexed massively parallel sequencing. 30/33 ingroup nodes resolved with ≥ 95% bootstrap support; this is a substantial improvement relative to prior studies, and shows massively parallel sequencing-based strategies can produce sufficient high quality sequence to reach support levels originally proposed for the phylogenetic bootstrap. Resampling simulations show that at least the entire plastome is necessary to fully resolve Pinus, particularly in rapidly radiating clades. Meta-analysis of 99 published infrageneric phylogenies shows that whole plastome analysis should provide similar gains across a range of plant genera. A disproportionate amount of phylogenetic information resides in two loci (ycf1, ycf2), highlighting their unusual evolutionary properties. Conclusion Plastome sequencing is now an efficient option for increasing phylogenetic resolution at lower taxonomic levels in plant phylogenetic and population genetic analyses. With continuing improvements in sequencing capacity, the strategies herein should revolutionize efforts requiring dense taxon and character sampling, such as phylogeographic

  5. Adiponectin plasma levels are increased by atorvastatin treatment in subjects at high cardiovascular risk.

    PubMed

    Blanco-Colio, Luis M; Martín-Ventura, Jose L; Gómez-Guerrero, Carmen; Masramon, Xavier; de Teresa, Eduardo; Farsang, Csaba; Gaw, Allan; Gensini, GianFranco; Leiter, Lawrence A; Langer, Anatoly; Egido, Jesús

    2008-05-31

    Adiponectin can suppress atherogenesis by inhibiting the adherence of monocytes, reducing their phagocytic activity, and suppressing the accumulation of modified lipoproteins in the vascular wall. Contradictory data have been reported about the effect of statins on adiponectin plasma levels. In this work, adiponectin plasma levels were measured in 102 statin-free subjects from the Spanish population of the Achieve Cholesterol Targets Fast with Atorvastatin Stratified Titration (ACTFAST) study, a 12-week, prospective, multi-centre, open-label trial which enrolled subjects with coronary heart disease, coronary heart disease-equivalent or a 10-year coronary heart disease risk >20%. Subjects were assigned to atorvastatin (10-80 mg/day) based on low-density lipoprotein (LDL)-cholesterol concentration at screening. For comparison, age and gender-matched blood donors (N=40) were used as controls. Control subjects did not present hypertension, hypercholesterolemia, diabetes, metabolic syndrome and history of cardiovascular diseases. Adiponectin levels were diminished in patients at high cardiovascular risk compared with control subjects [4166 (3661-4740) vs 5806 (4764-7075) ng/ml respectively; geometric mean (95% CI); P<0.0001]. In the whole population, atorvastatin treatment increased adiponectin levels [9.7 (3.2-16.7);% Change (95% CI); P=0.003]. This increment was in a dose-dependent manner; maximal effect observed with atorvastatin 80 mg/d [24.7 (5.7-47.1); P=0.01]. Adiponectin concentrations were positively correlated with high-density lipoprotein-cholesterol both before and after atorvastatin treatment. No association was observed between adiponectin and LDL-cholesterol before and after atorvastatin treatment. In conclusion, atorvastatin increased adiponectin plasma levels in subjects at high cardiovascular risk, revealing a novel anti-inflammatory effect of this drug.

  6. High Levels of Serum Prolactin Protect Against Diabetic Retinopathy by Increasing Ocular Vasoinhibins

    PubMed Central

    Arnold, Edith; Rivera, José C.; Thebault, Stéphanie; Moreno-Páramo, Daniel; Quiroz-Mercado, Hugo; Quintanar-Stéphano, Andrés; Binart, Nadine; Martínez de la Escalera, Gonzalo; Clapp, Carmen

    2010-01-01

    OBJECTIVE Increased retinal vasopermeability (RVP) occurs early in diabetes and is crucial for the development of sight-threatening proliferative diabetic retinopathy (DR). The hormone prolactin (PRL) is proteolytically processed to vasoinhibins, a family of peptides that inhibit the excessive RVP related to DR. Here, we investigate the circulating levels of PRL in association with DR in men and test whether increased circulating PRL, by serving as a source of ocular vasoinhibins, can reduce the pathological RVP in diabetes. RESEARCH DESIGN AND METHODS Serum PRL was evaluated in 40 nondiabetic and 181 diabetic men at various stages of DR. Retinal vasoinhibins were measured in rats rendered hyperprolactinemic by placing two anterior pituitary grafts under the kidney capsule and in PRL receptor–null mice. RVP was determined in hyperprolactinemic rats subjected to the intraocular injection of vascular endothelial growth factor (VEGF) or made diabetic with streptozotocin. RESULTS The circulating levels of PRL increased in diabetes and were higher in diabetic patients without retinopathy than in those with proliferative DR. In rodents, hyperprolactinemia led to vasoinhibin accumulation within the retina; genetic deletion of the PRL receptor prevented this effect, indicating receptor-mediated incorporation of systemic PRL into the eye. Hyperprolactinemia reduced both VEGF-induced and diabetes-induced increase of RVP. This reduction was blocked by bromocriptine, an inhibitor of pituitary PRL secretion, which lowers the levels of circulating PRL and retinal vasoinhibins. CONCLUSIONS Circulating PRL influences the progression of DR after its intraocular conversion to vasoinhibins. Inducing hyperprolactinemia may represent a novel therapy against DR. PMID:20823101

  7. A proteomic analysis of rice seed germination as affected by high temperature and ABA treatment.

    PubMed

    Liu, Shu-Jun; Xu, Heng-Heng; Wang, Wei-Qing; Li, Ni; Wang, Wei-Ping; Møller, Ian Max; Song, Song-Quan

    2015-05-01

    Seed germination is a critical phase in the plant life cycle, but the specific events associated with seed germination are still not fully understood. In this study, we used two-dimensional gel electrophoresis followed by mass spectrometry to investigate the changes in the proteome during imbibition of Oryza sativa seeds at optimal temperature with or without abscisic acid (ABA) and high temperature (germination thermoinhibition) to further identify and quantify key proteins required for seed germination. A total of 121 protein spots showed a significant change in abundance (1.5-fold increase/decrease) during germination under all conditions. Among these proteins, we found seven proteins specifically associated with seed germination including glycosyl hydrolases family 38 protein, granule-bound starch synthase 1, Os03g0842900 (putative steroleosin-B), N-carbamoylputrescine amidase, spermidine synthase 1, tubulin α-1 chain and glutelin type-A; and a total of 20 imbibition response proteins involved in energy metabolism, cell growth, cell defense and storage proteins. High temperature inhibited seed germination by decreasing the abundance of proteins involved in methionine metabolism, amino acid biosynthesis, energy metabolism, reserve degradation, protein folding and stress responses. ABA treatment inhibited germination and decreased the abundance of proteins associated with methionine metabolism, energy production and cell division. Our results show that changes in many biological processes including energy metabolism, protein synthesis and cell defense and rescue occurred as a result of all treatments, while enzymes involved in methionine metabolism and weakening of cell wall specifically accumulated when the seeds germinated at the optimal temperature.

  8. Increasing 14N NQR signal by 1H-14N level crossing with small magnetic fields.

    PubMed

    Thurber, Kent R; Sauer, Karen L; Buess, Michael L; Klug, Christopher A; Miller, Joel B

    2005-11-01

    NQR detection of materials, such as TNT, is hindered by the low signal-to-noise ratio at low NQR frequencies. Sweeping small (0-26 mT) magnetic fields to shift the (1)H NMR frequency relative to the (14)N NQR frequencies can provide a significant increase of the (14)N NQR signal-to-noise ratio. Three effects of (1)H-(14)N level crossing are demonstrated in diglycine hydrochloride and TNT. These effects are (1) transferring (1)H polarization to one or more of the (14)N transitions, including the use of an adiabatic flip of the (1)H polarization during the field sweep, (2) shortening the effective (14)N T(1) by the interaction of (1)H with the (14)N transitions, (3) "level transfer" effect where the third (14)N (spin 1) energy level or other (14)N sites with different NQR frequency are used as a reservoir of polarization which is transferred to the measured (14)N transition by the (1)H. The (14)N NQR signal-to-noise ratio can be increased by a factor of 2.5 for one (14)N site in diglycine hydrochloride (and 2.2 in TNT), even though the maximum (1)H frequency used in this work, 111 6 kHz, is only 30% larger than the measured (14)N frequencies (834 kHz for diglycine hydrochloride and 843 kHz for TNT).

  9. Longer-term increased cortisol levels in young people with mental health problems

    PubMed Central

    Heinze, Kareen; Lin, Ashleigh; Reniers, Renate L.E.P.; Wood, Stephen J.

    2016-01-01

    Disturbance of hypothalamus–pituitary–adrenal axis activity is commonly reported in a range of mental disorders in blood, saliva and urine samples. This study aimed to look at longer-term cortisol levels and their association with clinical symptoms. Hair strands of 30 young people (16–25 years) presenting with mental health problems (Mage±SD=21±2.4, 26 females) and 28 healthy controls (HC, Mage±SD=20±2.9, 26 females) were analyzed for cortisol concentrations, representing the past 6 months prior to hair sampling. Clinical participants completed an assessment on psychiatric symptoms, functioning and lifestyle factors. All participants completed the Perceived Stress Scale. Hair cortisol concentrations representing the past 3 (but not 3–6) months were significantly increased in clinical participants compared to HC. Perceived stress in the past month was significantly higher in clinical participants compared to HC, but not significantly correlated with hair cortisol. Hair cortisol levels were not significantly associated with any other measures. Hair segment analyses revealed longer-term increased levels of cortisol in the past 3 months in early mental health problems. Further insight into the role of cortisol on the pathogenesis of mental illnesses requires longitudinal studies relating cortisol to psychopathology and progression of illness. PMID:26749569

  10. Encephalitis and CSF increased level of interferon-α in Kikuchi-Fujimoto disease.

    PubMed

    Guéguen, Antoine; Sené, Thomas; Maillart, Elisabeth; Gout, Olivier

    2012-08-27

    Neurological manifestations have been reported in Kikuchi-Fujimoto disease (KFD). Characteristics of brain lesions are not defined. In addition, no biological indexes are known to help clinicians along the diagnosis process. The authors describe encephalitis associated with KFD. Brain MRI, positron emission tomography (PET) scan and a large biological assessment including interferon α (INF-α) level measurement in cerebrospinal fluid (CSF) were performed. A 39-year-old man with chronic headaches developed diplopia, slow ideation and behavioural disturbances. MRI showed brain lesions particularly in the pontine region and internal temporal lobes with enhancement of the perivacular space and the walls of the lateral ventricle. The IFN-α level was increased in the CSF without viral infection. Cervical and mediastinal adenitis were evident as a hypermetabolic focus on a PET scan, and biopsy confirmed the diagnosis of KFD. The encephalitis spontaneously remitted. The authors characterised brain lesions especially related to KFD in association with increased of IFN-α level in the CSF.

  11. Increased IgG4 levels in children with autism disorder

    PubMed Central

    Enstrom, Amanda; Krakowiak, Paula; Onore, Charity; Pessah, Isaac N.; Hertz-Picciotto, Irva; Hansen, Robin L.; Van de Water, Judy A.; Ashwood, Paul

    2009-01-01

    Accumulating evidence indicates that immune dysfunction is associated with autism disorders in a significant subset of children. Previous reports have shown abnormal immunoglobulin (Ig) levels, including an increased presence of autoreactive antibodies in the circulation of individuals with autism. As IgG is the predominant antibody isotype in circulation, we expected that an altered immune response could result in an abnormal IgG subclass profile in children with autism. We examined circulating plasma levels of IgG1, IgG2, IgG3, and IgG4 in 241 children from the CHARGE (Childhood Autism Risks from Genetics and the Environment) study, a large epidemiologic case-control investigation, including 114 children who meet full criteria for autism disorder (AU), 96 typically developing control children (TD) from a randomly selected sample of the general population, and 31 children with developmental delays (DD). We report significantly increased levels of the IgG4 subclass in children with AU compared with TD control children (p=0.016) and compared with DD controls (p=0.041). These results may suggest an underlying immunological abnormality in AU subjects resulting in elevated IgG4 production. Further investigation is necessary to elucidate the relationship between immunological findings and behavioral impairments in autism. PMID:19136055

  12. Longer-term increased cortisol levels in young people with mental health problems.

    PubMed

    Heinze, Kareen; Lin, Ashleigh; Reniers, Renate L E P; Wood, Stephen J

    2016-02-28

    Disturbance of hypothalamus-pituitary-adrenal axis activity is commonly reported in a range of mental disorders in blood, saliva and urine samples. This study aimed to look at longer-term cortisol levels and their association with clinical symptoms. Hair strands of 30 young people (16-25 years) presenting with mental health problems (Mage±SD=21±2.4, 26 females) and 28 healthy controls (HC, Mage±SD=20±2.9, 26 females) were analyzed for cortisol concentrations, representing the past 6 months prior to hair sampling. Clinical participants completed an assessment on psychiatric symptoms, functioning and lifestyle factors. All participants completed the Perceived Stress Scale. Hair cortisol concentrations representing the past 3 (but not 3-6) months were significantly increased in clinical participants compared to HC. Perceived stress in the past month was significantly higher in clinical participants compared to HC, but not significantly correlated with hair cortisol. Hair cortisol levels were not significantly associated with any other measures. Hair segment analyses revealed longer-term increased levels of cortisol in the past 3 months in early mental health problems. Further insight into the role of cortisol on the pathogenesis of mental illnesses requires longitudinal studies relating cortisol to psychopathology and progression of illness.

  13. Dietary Cholesterol Impairs Memory and Memory Increases Brain Cholesterol and Sulfatide Levels

    PubMed Central

    Darwish, Deya S.; Wang, Desheng; Konat, Gregory W.; Schreurs, Bernard G.

    2011-01-01

    Cholesterol and sulfatides play many important roles in learning and memory. To date, our observations about the effects of cholesterol on learning have been assessed during response acquisition i.e., the learning of a new memory. Here we report for the first time on the effect of a cholesterol diet on a previously formed memory. Rabbits were given trace conditioning of the nictitating membrane response for ten days, then fed a 2% cholesterol diet for eight weeks, and then assessed for memory recall of the initially learned task. We show that dietary cholesterol had an adverse effect on memory recall. Second, we investigated whether dietary cholesterol caused an increase in brain cholesterol and sulfatide levels in four major brain structures (hippocampus, frontal lobe, brainstem, and cerebellum) using a technique for analyzing myelin and myelin-free fractions separately. Although our data confirm previous findings that dietary cholesterol does not directly affect cholesterol and establish that it does not affect sulfatide levels in the brain, these levels did increase rather significantly in the hippocampus and frontal lobe as a function of learning and memory. PMID:20141286

  14. Increased circulating levels of tissue kallikrein in systemic sclerosis correlate with microvascular involvement

    PubMed Central

    Del Rosso, A; Distler, O; Milia, A; Emanueli, C; Ibba-Manneschi, L; Guiducci, S; Conforti, M; Generini, S; Pignone, A; Gay, S; Madeddu, P; Matucci-Cerinic, M

    2005-01-01

    Background: In systemic sclerosis (SSc) the lack of an angiogenic response to hypoxia may be due to inappropriate synthesis of angiogenic and angiostatic factors. Tissue kallikrein (t-kallikrein), regulating the kallikrein-kinin system and acting on the microcirculation, is a potent angiogenic agent, and kallistatin is its natural inhibitor. Objective: To evaluate, in patients with SSc, t-kallikrein and kallistatin levels and their correlation with clinical features and measures of microvascular involvement. Patients and methods: Serum levels of t-kallikrein and kallistatin (ELISA) and t-kallikrein skin expression (immunohistochemistry) were studied in patients with SSc, and evaluated for subset (dSSc or lSSc), clinical and immunological features, and microvascular involvement (ulcers, telangiectasias, nailfold videocapillaroscopy). Results: Circulating levels of t-kallikrein were higher in SSc than in controls (p<0.001). T-kallikrein did not differ between lSSc and dSSc, although it was higher in lSSc than in controls (p<0.001).T-kallikrein levels were higher in patients with early and active capillaroscopic pattern than in those with late pattern (p = 0.019 and 0.023). Patients with giant capillaries and capillary microhaemorrhages had higher t-kallikrein concentrations than patients with architectural derangement (p = 0.04). No differences in kallistatin levels were detected between patients with SSc and controls, or between lSSc and dSSc. In early SSc skin, the presence of t-kallikrein was found in endothelial and in perivascular inflammatory cells, while no staining in skin of advanced SSc was detected. Conclusion: T-kallikrein levels are increased in patients with SSc, particularly in lSSc, and are associated with early and active capillaroscopic patterns. T-kallikrein may play a part in SSc microvascular changes. PMID:15708892

  15. Conditioning causes an increase in Glucose Transporter-4 levels in mononuclear cells in sled dogs

    PubMed Central

    Schnurr, Theresia M.; Reynolds, Arleigh J.; Gustafson, Sally J.; Duffy, Lawrence K.; Dunlap, Kriya L.

    2014-01-01

    This study was designed to investigate the effects of physical conditioning on the expression of the insulin sensitive glucose transporter 4 protein (GLUT4) on mononuclear cells and HOMA-IR levels in dogs and compared to results reported in human skeletal muscle and the skeletal muscle of rodent models. Blood was sampled from conditioned dogs (n=8) and sedentary dogs (n=8). The conditioned dogs were exercised four months prior the experiment and were following a uniform training protocol, whereas the sedentary dogs were not. GLUT4 expression in mononuclear cells and plasma insulin levels were measured using commercially available enzyme-linked immunosorbent assay (ELISA). Blood glucose levels were determined using blood plasma. HOMA-IR was calculated using plasma insulin and blood glucose levels using the linear approximation formula. Our results indicate that the state of conditioning had a significant effect on the GLUT4 expression at the surface of mononuclear cells. HOMA-IR was also affected by conditioning in dogs. GLUT4 levels in mononuclear cells of sled dogs were inversely correlated with the homeostasis model assessment of insulin sensitivity. This study demonstrates that conditioning increases GLUT4 levels in mononuclear cells of sled dogs as it has been previously reported in skeletal muscle. Our results support the potential of white blood cells as a proxy tissue for studying insulin signaling and may lead to development of a minimally invasive and direct marker of insulin resistance. This may be the first report of GLUT4 in mononuclear cells in response to exercise and measured with ELISA. PMID:25236492

  16. Increased Blood Lactate Level Deteriorates Running Economy in World Class Endurance Athletes.

    PubMed

    Hoff, Jan; Støren, Øyvind; Finstad, Arnstein; Wang, Eivind; Helgerud, Jan

    2016-05-01

    Blood lactate accumulation is associated with development of muscle fatigue and negatively correlated to endurance performance. No research has quantified the effects of lactate presence at moderate levels of lactate accumulation. The purpose of this study was to test whether 2 moderate blood lactate concentration levels affect running economy (RE) when running at the individual lactate threshold (LT). Seven male world class endurance athletes with an average V[Combining Dot Above]O2max of 80.7 ± 2.7 ml·kg·min or 5.8 ± 0.5 L·min participated in this study. After the V[Combining Dot Above]O2max test, the subjects were resting or walking and in a random order tested for RE at their LT velocity when the blood lactate level reached either 3 mmol·L or 5 mmol·L. After a new 5-minute exercising period at maximal aerobic velocity, the crossover lactate value RE testing was performed. Running economy was significantly (p ≤ 0.05) deteriorated from 0.668 ± 0.044 to 0.705 ± 0.056 ml·kg·m or 5.5% (p ≤ 0.05) for blood lactate level of 3 mmol·L compared with 5 mmol·L, respectively. Increased lactate level from 3 to 5 mmol·L is thus accompanied by deteriorated RE at LT running velocity. The deteriorated RE at moderate levels of lactate concentration emphasizes the importance of avoiding intensities above LT in the early parts of a dominantly aerobic endurance competition. It also emphasizes the importance of a high V[Combining Dot Above]O2max for aerobic endurance athletes and may partly explain the V[Combining Dot Above]O2 slow component as impaired RE.

  17. Increase California-Oregon Coastal Summer Sea Level Fog from 1950 to 2007

    NASA Astrophysics Data System (ADS)

    Dorman, C. E.

    2015-12-01

    An analysis is presented of the marine fog distribution based upon the International Comprehensive Ocean-Atmosphere Data Set (ICOADS) ship observations taken during 1950-2007. Deep fog occurrence is reported in routine weather reports that are encoded in an ICOADS ship observation. Occurrence is estimated by the number of deep fog observations divided by the total present weather observations in a one-degree area centered on latitude and longitude grid point intersections. The mean fog occurrence for the summer (June-July-August) 1950-2007 was computed for each one degree point. There is a long term, deep fog occurrence maximum on the California-Oregon coast with its highest value of 16.6 % at 38° N 123° W. This fog maximum is coincident with coldest June-July-August sea surface temperatures (SST) along the coast. To compute annual averages of the maximum, a block average was based on the 19 over water grid points with the deep fog occurrences generally greater than 0.6 times the highest long term maximum value that extended along the California-Oregon coast from 37° N to 44° N. The June-July-August block averaged, annual value computed for each of the 58 summers for the period 1950-2007 has a distinct positive trend. A line fitted to the data has a deep fog percent occurrence increase of +7.4 % from 1950 through 2007 or a trend of +0.13 % per year. The Mann-Kendall test was applied and the trend is significant at the 0.05 level. The increase in long term coastal fog is coincident with a decrease in the California-Oregon coastal SST. The SST decrease is consistent with interior California land temperatures increasing, increasing the cross shore sea level pressure gradient, and increasing the along coast winds creating a positive feedback that causes more upwelling and lower SST.

  18. Low Levels of Physical Activity Increase Metabolic Responsiveness to Cold in a Rat (Rattus fuscipes)

    PubMed Central

    Seebacher, Frank; Glanville, Elsa J.

    2010-01-01

    Background Physical activity modulates expression of metabolic genes and may therefore be a prerequisite for metabolic responses to environmental stimuli. However, the extent to which exercise interacts with environmental conditions to modulate metabolism is unresolved. Hence, we tested the hypothesis that even low levels of physical activity are beneficial by improving metabolic responsiveness to temperatures below the thermal neutral zone, thereby increasing the capacity for substrate oxidation and energy expenditure. Methodology/Principal Findings We used wild rats (Rattus fuscipes) to avoid potential effects of breeding on physiological phenotypes. Exercise acclimation (for 30 min/day on 5 days/week for 30 days at 60% of maximal performance) at 22°C increased mRNA concentrations of PGC1α, PPARδ, and NRF-1 in skeletal muscle and brown adipose tissue compared to sedentary animals. Lowering ambient temperature to 12°C caused further increases in relative expression of NRF-1 in skeletal muscle, and of PPARδ of brown adipose tissue. Surprisingly, relative expression of UCP1 increased only when both exercise and cold stimuli were present. Importantly, in sedentary animals cold acclimation (12°C) alone did not change any of the above variables. Similarly, cold alone did not increase maximum capacity for substrate oxidation in mitochondria (cytochrome c oxidase and citrate synthase activities) of either muscle or brown adipose tissue. Animals that exercised regularly had higher exercise induced metabolic rates in colder environments than sedentary rats, and temperature induced metabolic scope was greater in exercised rats. Conclusions/Significance Physical activity is a necessary prerequisite for the expression of transcriptional regulators that influence a broad range of physiological functions from energy metabolism to cardiovascular function and nutrient uptake. A sedentary lifestyle leads to decreased daily energy expenditure because of a lack of direct use

  19. Delta oscillations induced by ketamine increase energy levels in sleep-wake related brain regions.

    PubMed

    Dworak, M; McCarley, R W; Kim, T; Basheer, R

    2011-12-01

    Neuronal signaling consumes much of the brain energy, mainly through the restoration of the membrane potential (MP) by ATP-consuming ionic pumps. We have reported that, compared with waking, ATP levels increase during the initial hours of natural slow-wave sleep, a time with prominent electroencephalogram (EEG) delta oscillations (0.5-4.5 Hz). We have hypothesized that there is a delta oscillation-ATP increase coupling, since, during delta waves, neurons exhibit a prolonged hyperpolarizing phase followed by a very brief phase of action potentials. However, direct proof of this hypothesis is lacking, and rapid changes in EEG/neuronal activity preclude measurement in the naturally sleeping brain. Thus, to induce a uniform state with pure delta oscillations and one previously shown to be accompanied by a similar pattern of neuronal activity during delta waves as natural sleep, we used ketamine-xylazine treatment in rats. We here report that, with this treatment, the high-energy molecules ATP and ADP increased in frontal and cingulate cortices, basal forebrain, and hippocampus compared with spontaneous waking. Moreover, the degree of ATP increase positively and significantly correlated with the degree of EEG delta activity. Supporting the hypothesis of decreased ATP consumption during delta activity, the ATP-consuming Na+-K+-ATPase mRNA levels were significantly decreased, whereas the mRNAs for the ATP-producing cytochrome c oxidase (COX) subunits COX III and COX IVa were unchanged. Taken together, these data support the hypothesis of a cortical delta oscillation-dependent reduction in ATP consumption, thus providing the brain with increased ATP availability, and likely occurring because of reduced Na+-K+-ATPase-related energy consumption.

  20. Towards increased waste loading in high level waste glasses: Developing a better understanding of crystallization behavior

    DOE PAGES

    Marra, James C.; Kim, Dong -Sang

    2014-12-18

    A number of waste components in US defense high level radioactive wastes (HLW) have proven challenging for current Joule heated ceramic melter (JCHM) operations and have limited the ability to increase waste loadings beyond already realized levels. Many of these ''troublesome'' waste species cause crystallization in the glass melt that can negatively impact product quality or have a deleterious effect on melter processing. Thus, recent efforts at US Department of Energy laboratories have focused on understanding crystallization behavior within HLW glass melts and investigating approaches to mitigate the impacts of crystallization so that increases in waste loading can be realized.more » Advanced glass formulations have been developed to highlight the unique benefits of next-generation melter technologies such as the Cold Crucible Induction Melter (CCIM). Crystal-tolerant HLW glasses have been investigated to allow sparingly soluble components such as chromium to crystallize in the melter but pass out of the melter before accumulating. The Hanford site AZ-101 tank waste composition represents a waste group that is waste loading limited primarily due to high concentrations of Fe2O3 (with higher Al2O3). Systematic glass formulation development utilizing slightly higher process temperatures and higher tolerance to spinel crystals demonstrated that an increase in waste loading of more than 20% could be achieved for this waste composition, and by extension higher loadings for wastes in the same group.« less

  1. Towards increased waste loading in high level waste glasses: Developing a better understanding of crystallization behavior

    SciTech Connect

    Marra, James C.; Kim, Dong -Sang

    2014-12-18

    A number of waste components in US defense high level radioactive wastes (HLW) have proven challenging for current Joule heated ceramic melter (JCHM) operations and have limited the ability to increase waste loadings beyond already realized levels. Many of these ''troublesome'' waste species cause crystallization in the glass melt that can negatively impact product quality or have a deleterious effect on melter processing. Thus, recent efforts at US Department of Energy laboratories have focused on understanding crystallization behavior within HLW glass melts and investigating approaches to mitigate the impacts of crystallization so that increases in waste loading can be realized. Advanced glass formulations have been developed to highlight the unique benefits of next-generation melter technologies such as the Cold Crucible Induction Melter (CCIM). Crystal-tolerant HLW glasses have been investigated to allow sparingly soluble components such as chromium to crystallize in the melter but pass out of the melter before accumulating. The Hanford site AZ-101 tank waste composition represents a waste group that is waste loading limited primarily due to high concentrations of Fe2O3 (with higher Al2O3). Systematic glass formulation development utilizing slightly higher process temperatures and higher tolerance to spinel crystals demonstrated that an increase in waste loading of more than 20% could be achieved for this waste composition, and by extension higher loadings for wastes in the same group.

  2. Increased levels of apoptosis in gastrocnemius skeletal muscle in patients with peripheral arterial disease.

    PubMed

    Mitchell, Robert G; Duscha, Brian D; Robbins, Jennifer L; Redfern, Shelley I; Chung, Jayer; Bensimhon, Daniel R; Kraus, William E; Hiatt, William R; Regensteiner, Judith G; Annex, Brian H

    2007-11-01

    Intermittent claudication (IC) is the major clinical manifestation of peripheral arterial disease (PAD). Apoptosis has been linked to skeletal muscle pathophysiology in other chronic diseases such as congestive heart failure. This study tested the hypothesis that there would be increased levels of apoptosis in the skeletal muscle of patients with PAD compared with control individuals. In total, 26 individuals with PAD and 28 age-appropriate controls underwent studies of peak oxygen consumption (peak VO2) and a gastrocnemius muscle biopsy in the most symptomatic leg. Muscle biopsies were analyzed for apoptosis and caspase-3 activity. Patients with PAD had a reduced peak VO2 compared with controls. Apoptosis was increased in those with PAD compared with age-appropriate controls (3.83% +/- 2.6 vs 1.53% +/- 0.96; p < 0.001). In conclusion, PAD is associated with increased levels of apoptosis in the peripheral skeletal muscle. Further study is required to ascertain whether apoptosis plays a role in decreased functional capacity.

  3. Plasma levels of soluble tumour necrosis factor receptors are increased in coal miners with pneumoconiosis.

    PubMed

    Schins, R P; Borm, P J

    1995-10-01

    Among other cytokines, tumour necrosis factor (TNF)-alpha is considered to play a key role in the development of mineral dust related fibrosis. Previously, we showed that ex-vivo release of TNF by peripheral blood monocytes is a marker for progression of coal workers' pneumoconiosis (CWP). Since soluble TNF receptors (sTNF-Rs) are believed to play an important regulatory role in systemic effects of TNF, we measured plasma levels of sTNF-R55 and sTNF-R75 in coal miners with (n = 28) or without (n = 76) CWP and in nonexposed controls (n = 29). sTNF-R75 levels were significantly increased in miners with CWP (2.09 +/- 0.44 ng.mL-1) versus the nonexposed controls (1.86 +/- 0.23 ng.mL-1). Neither sTNF-R55 nor sTNF-R75 were related to exposure, stage of pneumoconiosis, smoking, or (spontaneous or ex-vivo induced) monocyte TNF-release. sTNF-R55 was increased in subjects with medication (especially those using cardiovascular drugs); upon exclusion of these subjects, sTNF-R55 was found also to be significantly increased in CWP. In conclusion, bearing in mind a confounding effect of medication, soluble TNF receptors are elevated in plasma of retired miners with coal workers' pneumoconiosis. These observations further support the important role of TNF-mediated pathways in the pathogenesis of mineral dust related fibrosis.

  4. Increased low-level chromosome 21 mosaicism in older individuals with Down syndrome

    SciTech Connect

    Jenkins, E.C.; Genovese, M.; Ye, Ling Ling

    1997-01-20

    During a study of the familial aggregation of Down syndrome (DS) and Alzheimer disease (AD), we observed an increase in mosaicism for disomy 21 in older individuals with DS. In a total of 213 DS subjects who were studied cytogenetically, only 1 of 121 (0.8%) under age 45 exhibited mosaicism, while 14 of 92 (15.2%) who were age 45 or older had mosaicism. Mosaicism in this report connotes {open_quotes}low-level{close_quotes} mosaicism, where all 15 individuals exhibited a modal chromosome number of 47 (i.e., trisomy 21), and at least two cells lacked one of the three chromosomes 21. The occurrence of aneuploidy for chromosomes 15, 17, and X increased with age, and an inverse correlation between chromosome loss and size was also observed. Because older individuals had not been karyotyped at birth, it was not possible to determine whether our observations were due to either increased survival of mosaic individuals or accumulation of disomy 21 cells via increased chromosome loss with aging of the trisomy 21 individual. Using a modeling approach involving life table methods, we obtained results that suggested acquired mosaicism as the predominant mechanism to explain our findings. These results support the hypothesis that as individuals with DS age, there is an increased loss of chromosome 21. 30 refs., 5 tabs.

  5. ABA inhibits germination but not dormancy release in mature imbibed seeds of Lolium rigidum Gaud.

    PubMed Central

    Goggin, Danica E.; Steadman, Kathryn J.; Emery, R. J. Neil; Farrow, Scott C.; Benech-Arnold, Roberto L.; Powles, Stephen B.

    2009-01-01

    Dormancy release in imbibed annual ryegrass (Lolium rigidum Gaud.) seeds is promoted in the dark but inhibited in the light. The role of abscisic acid (ABA) in inhibition of dormancy release was found to be negligible, compared with its subsequent effect on germination of dormant and non-dormant seeds. Inhibitors of ABA metabolism had the expected effects on seed germination but did not influence ABA concentration, suggesting that they act upon other (unknown) factors regulating dormancy. Although gibberellin (GA) synthesis was required for germination, the influence of exogenous GA on both germination and dormancy release was minor or non-existent. Embryo ABA concentration was the same following treatments to promote (dark stratification) and inhibit (light stratification) dormancy release; exogenous ABA had no effect on this process. However, the sensitivity of dark-stratified seeds to ABA supplied during germination was lower than that of light-stratified seeds. Therefore, although ABA definitely plays a role in the germination of annual ryegrass seeds, it is not the major factor mediating inhibition of dormancy release in imbibed seeds. PMID:19487389

  6. The Dynamics of Embolism Refilling in Abscisic Acid (ABA)-Deficient Tomato Plants

    PubMed Central

    Secchi, Francesca; Perrone, Irene; Chitarra, Walter; Zwieniecka, Anna K.; Lovisolo, Claudio; Zwieniecki, Maciej A.

    2013-01-01

    Plants are in danger of embolism formation in xylem vessels when the balance between water transport capacity and transpirational demand is compromised. To maintain this delicate balance, plants must regulate the rate of transpiration and, if necessary, restore water transport in embolized vessels. Abscisic acid (ABA) is the dominant long-distance signal responsible for plant response to stress, and it is possible that it plays a role in the embolism/refilling cycle. To test this idea, a temporal analysis of embolism and refilling dynamics, transpiration rate and starch content was performed on ABA-deficient mutant tomato plants. ABA-deficient mutants were more vulnerable to embolism formation than wild-type plants, and application of exogenous ABA had no effect on vulnerability. However, mutant plants treated with exogenous ABA had lower stomatal conductance and reduced starch content in the xylem parenchyma cells. The lower starch content could have an indirect effect on the plant’s refilling activity. The results confirm that plants with high starch content (moderately stressed mutant plants) were more likely to recover from loss of water transport capacity than plants with low starch content (mutant plants with application of exogenous ABA) or plants experiencing severe water stress. This study demonstrates that ABA most likely does not play any direct role in embolism refilling, but through the modulation of carbohydrate content, it could influence the plant’s capacity for refilling. PMID:23263667

  7. Production of ABA responses requires both the nuclear and cytoplasmic functional involvement of PYR1.

    PubMed

    Park, EunJoo; Kim, Tae-Houn

    2017-02-26

    Abscisic acid (ABA) enhances stress tolerant responses in plants against unfavorable environmental conditions. In Arabidopsis, ABA promotes interactions between PYR/PYL/RCARs and PP2C, thereby allowing SnRK2s to phosphorylate downstream components required for the regulation of gene expression or for gating ion channels. Because PYR1 is known to localize to nucleus and cytoplasm it is a question whether nuclear or cytoplasmic PYR1 confer different functions to the ABA signaling pathway, as has been previously shown for regulatory proteins. In order to answer this question, transgenic lines expressing nuclear PYR1 were generated in an ABA insensitive mutant background. Enforced nuclear expression of PYR1 was examined by confocal microscopy and western blot analysis. Physiological analyses of the transgenic lines demonstrated that nuclear PYR1 is sufficient to generate ABA responses, such as, the inhibition of seed germination, root growth inhibition, the induction of gene expression, and stomatal closing movement. However, for the full recovery of ABA responses in the mutant background cytoplasmic PYR1 was required. The study suggests both nuclear and cytoplasmic PYR1 participate in the control of ABA signal transduction.

  8. A Comprehensive Proteomic Survey of ABA-Induced Protein Phosphorylation in Rice (Oryza sativa L.)

    PubMed Central

    Qiu, Jiehua; Hou, Yuxuan; Wang, Yifeng; Li, Zhiyong; Zhao, Juan; Tong, Xiaohong; Lin, Haiyan; Wei, Xiangjin; Ao, Hejun; Zhang, Jian

    2017-01-01

    abscisic acid (ABA) is a key phytohormone regulating plant development and stress response. The signal transduction of ABA largely relies on protein phosphorylation. However; little is known about the phosphorylation events occurring during ABA signaling in rice thus far. By employing a label-free; MS (Mass Spectrometry)-based phosphoproteomic approach; we identified 2271 phosphosites of young rice seedlings and their intensity dynamics in response to ABA; during which 1060 proteins were found to be differentially phosphorylated. Western-blot analysis verified the differential phosphorylation pattern of D1, SMG1 and SAPK9 as indicated by the MS result; suggesting the high reliability of our phosphoproteomic data. The DP (differentially phosphorylated) proteins are extensively involved in ABA as well as other hormone signaling pathways. It is suggested that ABA antagonistically regulates brassinosteroid (BR) signaling via inhibiting BR receptor activity. The result of this study not only expanded our knowledge of rice phosphoproteome, but also shed more light on the pattern of protein phosphorylation in ABA signaling. PMID:28054942

  9. Validation of functional fetal autonomic brain age score fABAS in 5 min short recordings.

    PubMed

    Hoyer, Dirk; Schneider, Uwe; Kowalski, Eva-Maria; Schmidt, Alexander; Witte, Otto W; Schleußner, Ekkehard; Hatzmann, Wolfgang; Grönemeyer, Dietrich Hw; van Leeuwen, Peter

    2015-11-01

    With the objective of evaluating the functional maturation age and developmental disturbances we have previously introduced the fetal autonomic brain age score (fABAS) using 30 min fetal magnetocardiographic recordings (fMCG, Jena). The score is based on heart rate pattern indices that are related to universal principles of developmental biology. The present work aims at the validation of the fABAS methodology on 5 min recordings from an independent database (fMCG, Bochum).We found high agreement of fABAS obtained from Jena normal fetuses (5 min subsets, n =  364) and Bochum recordings (n =  322, normal fetuses). fABAS of 48 recordings from fetuses with intra-uterine growth restriction (IUGR, Bochum) was reduced in most of the cases, a result consistent with IUGR fetuses from Jena previously reported. fABAS calculated from 5 min snapshots only partly covers the accuracy when compared to fABAS from 30 min recordings. More precise diagnosis requires longer recordings.fABAS obtained from fMCG recordings is a strong candidate for standardized assessment of functional maturation age and developmental disturbances. Even 5 min recordings seem to be valuable for screening for maturation problems.

  10. ABA inhibits germination but not dormancy release in mature imbibed seeds of Lolium rigidum Gaud.

    PubMed

    Goggin, Danica E; Steadman, Kathryn J; Emery, R J Neil; Farrow, Scott C; Benech-Arnold, Roberto L; Powles, Stephen B

    2009-01-01

    Dormancy release in imbibed annual ryegrass (Lolium rigidum Gaud.) seeds is promoted in the dark but inhibited in the light. The role of abscisic acid (ABA) in inhibition of dormancy release was found to be negligible, compared with its subsequent effect on germination of dormant and non-dormant seeds. Inhibitors of ABA metabolism had the expected effects on seed germination but did not influence ABA concentration, suggesting that they act upon other (unknown) factors regulating dormancy. Although gibberellin (GA) synthesis was required for germination, the influence of exogenous GA on both germination and dormancy release was minor or non-existent. Embryo ABA concentration was the same following treatments to promote (dark stratification) and inhibit (light stratification) dormancy release; exogenous ABA had no effect on this process. However, the sensitivity of dark-stratified seeds to ABA supplied during germination was lower than that of light-stratified seeds. Therefore, although ABA definitely plays a role in the germination of annual ryegrass seeds, it is not the major factor mediating inhibition of dormancy release in imbibed seeds.

  11. The dynamics of embolism refilling in abscisic acid (ABA)-deficient tomato plants.

    PubMed

    Secchi, Francesca; Perrone, Irene; Chitarra, Walter; Zwieniecka, Anna K; Lovisolo, Claudio; Zwieniecki, Maciej A

    2012-12-24

    Plants are in danger of embolism formation in xylem vessels when the balance between water transport capacity and transpirational demand is compromised. To maintain this delicate balance, plants must regulate the rate of transpiration and, if necessary, restore water transport in embolized vessels. Abscisic acid (ABA) is the dominant long-distance signal responsible for plant response to stress, and it is possible that it plays a role in the embolism/refilling cycle. To test this idea, a temporal analysis of embolism and refilling dynamics, transpiration rate and starch content was performed on ABA-deficient mutant tomato plants. ABA-deficient mutants were more vulnerable to embolism formation than wild-type plants, and application of exogenous ABA had no effect on vulnerability. However, mutant plants treated with exogenous ABA had lower stomatal conductance and reduced starch content in the xylem parenchyma cells. The lower starch content could have an indirect effect on the plant's refilling activity. The results confirm that plants with high starch content (moderately stressed mutant plants) were more likely to recover from loss of water transport capacity than plants with low starch content (mutant plants with application of exogenous ABA) or plants experiencing severe water stress. This study demonstrates that ABA most likely does not play any direct role in embolism refilling, but through the modulation of carbohydrate content, it could influence the plant's capacity for refilling.

  12. IL-33 circulating serum levels are increased in patients with non-segmental generalized vitiligo.

    PubMed

    Vaccaro, Mario; Cicero, Francesca; Mannucci, Carmen; Calapai, Gioacchino; Spatari, Giovanna; Barbuzza, Olga; Cannavò, Serafinella P; Gangemi, Sebastiano

    2016-09-01

    IL-33 is a recently identified cytokine, encoded by the IL-33 gene, which is a member of the IL-1 family that drives the production of T-helper-2 (Th-2)-associated cytokines. Serum levels of IL-33 have been reported to be up-regulated in various T-helper (Th)-1/Th-17-mediated diseases, such as psoriasis, rheumatoid arthritis, and inflammatory bowel. To investigate whether cytokine imbalance plays a role in the pathogenesis of vitiligo, we performed a case-control association study by enzyme-linked immunosorbent assay of IL-33 in our patients. IL-33 serum levels were measured by a quantitative enzyme immunoassay technique in patients with non-segmental generalized vitiligo and compared with those of healthy controls. IL-33 serum levels in patients with vitiligo were significantly increased than those in healthy controls. There was a positive correlation of IL-33 serum levels with extension of vitiligo and disease activity. This study suggests a possible systemic role of IL-33 in the pathogenesis of vitiligo. Inhibiting IL-33 activity might be a novel therapeutic strategy in the treatment of autoimmune inflammatory disease, like vitiligo.

  13. The Tellurium compound, AS101, increases SIRT1 level and activity and prevents type 2 diabetes.

    PubMed

    Halperin-Sheinfeld, Meital; Gertler, Asaf; Okun, Eitan; Sredni, Benjamin; Cohen, Haim Y

    2012-06-01

    The histone deacetylase, SIRT1, plays a major role in glucose regulation and lipid metabolism. Ammonium Trichloro (dioxoethylene-o,o') Tellurate, AS101, is a potent in vitro and in vivo immunomodulator, with several potential therapeutic applications. AS101 administration resulted in upregulation of SIRT1 protein expression and activity. These effects were associated with decreased levels of serum insulin like growth factor-1 (IGF-1) and of insulin. The properties of AS101 prompted us to investigate its potential therapeutic role in rats with type 2 diabetes (T2D). T2D was induced by a high fat diet combined with a low dose of Streptozotocin (STZ). Treatment with AS101 before manifestation of hyperglycemia, resulted in increased insulin sensitivity, and decreased blood glucose levels, and prevented symptoms of diabetes including defective glucose clearance, fatty liver, and abnormal distribution of insulin-producing beta cells in the pancreas. Treatment after disease emergence resulted in partial restoration of normal glucose homeostasis. Diabetic rats showed a reduction in liver SIRT1 levels. In both treatment regimens the reduction in SIRT1 levels in the liver were blocked by AS101 consumption. Together, these findings demonstrate the therapeutic potential of AS101 for treating T2D, and for reversing impaired fat and glucose metabolism.

  14. Increased levels of antibodies against heat shock proteins in stroke patients.

    PubMed

    Banecka-Majkutewicz, Zyta; Grabowski, Michał; Kadziński, Leszek; Papkov, Aliaksei; Węgrzyn, Alicja; Banecki, Bogdan

    2014-01-01

    Ischemic stroke is the second leading cause of death worldwide. One of the main risk factors of the ischemic stroke is atherosclerosis which is a chronic inflammatory and immune-mediated disease. Bacterial infections generate specific human antibodies against various antigens, including Hsps. It has been demonstrated that Hsps are selectively overexpressed in the atherosclerotic lesions. The amino acid sequence homology between human and bacterial Hsps may lead to an autoimmune response by immunological cross-reaction. Such immune response against Hsps overexpressed in the blood vessels under stressful conditions may contribute to inflammatory processes and subsequent development of atherosclerosis. In this study we determined the antibody levels against bacterial and human Hsp by ELISA in blood plasma obtained from stroke patients. Using ANOVA we analyzed levels of Hsp-antibodies in control and patient groups and correlate them with several stroke risk factors. The group of stroke patients had elevated levels of anti-Hsp antibodies compared to the control group. We also discovered an antibody level increase in patients that previously underwent another stroke. Our data provide evidence that autoimmunity could underlie formation of atherosclerosis plaque leading to stroke.

  15. Increased migration levels of bisphenol A from polycarbonate baby bottles after dishwashing, boiling and brushing.

    PubMed

    Brede, C; Fjeldal, P; Skjevrak, I; Herikstad, H

    2003-07-01

    Baby bottles are often made of polycarbonate plastic. Impurities remaining in the bottle from the monomer bisphenol A can migrate from the plastic bottles into baby food, thereby causing a health concern. Previous migration testing of new baby bottles showed only trace migration levels of the substance. In the present work, polycarbonate baby bottles were subjected to simulated use by dishwashing, boiling and brushing. Migration testing performed with both new and used bottles revealed a significant increase in migration of bisphenol A due to use. This finding might be explained by polymer degradation. Bisphenol A was determined in 200-ml samples of water food simulant by a method based on solid-phase extraction followed by gas chromatography coupled with mass spectrometry. The detection limit was 0.1 microg l(-1). Twelve different polycarbonate baby bottles were tested by filling them with hot water (100 degrees C) for 1 h. The mean bisphenol A level from new bottles was 0.23 + -0.12 microg l(-1), while the mean levels from bottles subjected to simulated use were 8.4 + -4 microg l(-1) (dishwashed 51 times) and 6.7 + -4 microg l(-1) (dishwashed 169 times), respectively. None of the bottles released bisphenol A at levels that exceed the recently established provisional tolerable daily intake (0.01 mg kg(-1) body weight/day) in the European Union.

  16. Increased Gustatory Response Score in Obesity and Association Levels with IL-6 and Leptin

    PubMed Central

    Remla, Nesrine; Hadjidj, Zeyneb; Ghezzaz, Kamel; Moulessehoul, Soraya; Aribi, Mourad

    2016-01-01

    Background. The aim of this study was to investigate the relationship between the circulating IL-6 and leptin levels with taste alteration in young obese patients. Methods. A retrospective case-control study was conducted in thirty obese patients and thirty age- and sex-matched healthy controls. Results. Circulating levels of IL-6 and leptin were significantly increased in obese patients than in controls. However, catalase and ORAC levels were significantly decreased in obese patients compared to controls. Additionally, obese participants had high scores for the detection of fats (gustatory response scores [GRS]; p < 0.001). Moreover, IL-6 and leptin were strongly associated with GRS alteration among patients with GRS 4 (resp., OR =17.5 [95% CI, 1.56–193.32; p = 0.007]; OR = 16 [95% CI, 1.69–151.11; p = 0.006]). For the Mantel-Haenszel common odds ratio estimate (MH OR), IL-6 and leptin were strongly associated with obesity, in patients with either GRS 4 or GRS > 4 (resp., MH OR = 8.77 [95% CI, 2.06–37.44; p = 0.003]; MH OR = 5.76 [95% CI, 1.64–20.24; p = 0.006]). Conclusions. In a low grade inflammation linked to obesity, taste alteration is associated with high levels of IL-6 and leptin. PMID:27413547

  17. Increased Gustatory Response Score in Obesity and Association Levels with IL-6 and Leptin.

    PubMed

    Remla, Nesrine; Hadjidj, Zeyneb; Ghezzaz, Kamel; Moulessehoul, Soraya; Aribi, Mourad

    2016-01-01

    Background. The aim of this study was to investigate the relationship between the circulating IL-6 and leptin levels with taste alteration in young obese patients. Methods. A retrospective case-control study was conducted in thirty obese patients and thirty age- and sex-matched healthy controls. Results. Circulating levels of IL-6 and leptin were significantly increased in obese patients than in controls. However, catalase and ORAC levels were significantly decreased in obese patients compared to controls. Additionally, obese participants had high scores for the detection of fats (gustatory response scores [GRS]; p < 0.001). Moreover, IL-6 and leptin were strongly associated with GRS alteration among patients with GRS 4 (resp., OR =17.5 [95% CI, 1.56-193.32; p = 0.007]; OR = 16 [95% CI, 1.69-151.11; p = 0.006]). For the Mantel-Haenszel common odds ratio estimate (MH OR), IL-6 and leptin were strongly associated with obesity, in patients with either GRS 4 or GRS > 4 (resp., MH OR = 8.77 [95% CI, 2.06-37.44; p = 0.003]; MH OR = 5.76 [95% CI, 1.64-20.24; p = 0.006]). Conclusions. In a low grade inflammation linked to obesity, taste alteration is associated with high levels of IL-6 and leptin.

  18. Loss of Arabidopsis thaliana Seed Dormancy is Associated with Increased Accumulation of the GID1 GA Hormone Receptors.

    PubMed

    Hauvermale, Amber L; Tuttle, Keiko M; Takebayashi, Yumiko; Seo, Mitsunori; Steber, Camille M

    2015-09-01

    Dormancy prevents seeds from germinating under favorable conditions until they have experienced dormancy-breaking conditions, such as after-ripening through a period of dry storage or cold imbibition. Abscisic acid (ABA) hormone signaling establishes and maintains seed dormancy, whereas gibberellin (GA) signaling stimulates germination. ABA levels decrease and GA levels increase with after-ripening and cold stratification. However, increasing GA sensitivity may also be critical to dormancy loss since increasing seed GA levels are detectable only with long periods of after-ripening and imbibition. After-ripening and cold stratification act additively to enhance GA hormone sensitivity in ga1-3 seeds that cannot synthesize GA. Since the overexpression of the GA receptor GID1 (GIBBERELLIN-INSENSITIVE DWARF1) enhanced this dormancy loss, and because gid1a gid1b gid1c triple mutants show decreased germination, the effects of dormancy-breaking treatments on GID1 mRNA and protein accumulation were examined. Partial after-ripening resulted in increased GID1b, but not GID1a or GID1c mRNA levels. Cold imbibition stimulated the accumulation of all three GID1 transcripts, but resulted in no increase in GA sensitivity during ga1-3 seed germination unless seeds were also partially after-ripened. This is probably because after-ripening was needed to enhance GID1 protein accumulation, independently of transcript abundance. The rise in GID1b transcript with after-ripening was not associated with decreased ABA levels, suggesting there is ABA-independent GID1b regulation by after-ripening and the 26S proteasome. GA and the DELLA RGL2 repressor of GA responses differentially regulated the three GID1 transcripts. Moreover, DELLA RGL2 appeared to switch between positive and negative regulation of GID1 expression in response to dormancy-breaking treatments.

  19. Fasting-induced increases in food hoarding are dependent on the foraging-effort level.

    PubMed

    Day, Diane E; Bartness, Timothy J

    2003-04-01

    Two strategies that have evolved to help animals meet energy demands are increases in body fat and in hoarded food. Reliance on each varies, but both are characterized by energy stored in excess of current demands for future use. Fasted Siberian hamsters decrease their lipid stores and, upon refeeding, food hoarding rather than food intake increases. Here, we tested the effect of foraging-effort level on fasting-induced increases in food hoarding and whether decreases in total body fat or individual fat pad masses were associated with the hoarding increases. This was accomplished by housing female Siberian hamsters in a foraging/hoarding system where they earned food pellets upon completion of a programmed number of wheel revolutions (10, 75 or 200 per 75-mg pellet), or had no foraging requirement (free food and an active or blocked running wheel). After baseline, half the hamsters in each group were food deprived for 32 h and then refed (control hamsters were killed after the fast without refeeding). Fasted-refed hamsters increased foraging and food hoarding, especially at the lowest foraging effort, but not food intake, with few exceptions. These responses became progressively smaller as foraging effort increased. Fasting induced similar losses in carcass lipid across foraging efforts, but the lipid loss was not uniform across the fat pads and was not clearly related to hoard size. Collectively, the fasting-induced, increased food hoarding may be triggered by an overall change in energy metabolism rather than by a general or fat-pad-specific decrease in lipid stores.

  20. Bothrops jararaca Venom Metalloproteinases Are Essential for Coagulopathy and Increase Plasma Tissue Factor Levels during Envenomation

    PubMed Central

    Yamashita, Karine M.; Alves, André F.; Barbaro, Katia C.; Santoro, Marcelo L.

    2014-01-01

    Background/Aims Bleeding tendency, coagulopathy and platelet disorders are recurrent manifestations in snakebites occurring worldwide. We reasoned that by damaging tissues and/or activating cells at the site of the bite and systemically, snake venom toxins might release or decrypt tissue factor (TF), resulting in activation of blood coagulation and aggravation of the bleeding tendency. Thus, we addressed (a) whether TF and protein disulfide isomerase (PDI), an oxireductase involved in TF encryption/decryption, were altered in experimental snake envenomation; (b) the involvement and significance of snake venom metalloproteinases (SVMP) and serine proteinases (SVSP) to hemostatic disturbances. Methods/Principal Findings Crude Bothrops jararaca venom (BjV) was preincubated with Na2-EDTA or AEBSF, which are inhibitors of SVMP and SVSP, respectively, and injected subcutaneously or intravenously into rats to analyze the contribution of local lesion to the development of hemostatic disturbances. Samples of blood, lung and skin were collected and analyzed at 3 and 6 h. Platelet counts were markedly diminished in rats, and neither Na2-EDTA nor AEBSF could effectively abrogate this fall. However, Na2-EDTA markedly reduced plasma fibrinogen consumption and hemorrhage at the site of BjV inoculation. Na2-EDTA also abolished the marked elevation in TF levels in plasma at 3 and 6 h, by both administration routes. Moreover, increased TF activity was also noticed in lung and skin tissue samples at 6 h. However, factor VII levels did not decrease over time. PDI expression in skin was normal at 3 h, and downregulated at 6 h in all groups treated with BjV. Conclusions SVMP induce coagulopathy, hemorrhage and increased TF levels in plasma, but neither SVMP nor SVSP are directly involved in thrombocytopenia. High levels of TF in plasma and TF decryption occur during snake envenomation, like true disseminated intravascular coagulation syndrome, and might be implicated in engendering

  1. Nitrous oxide plus isoflurane induces apoptosis and increases β-amyloid protein levels

    PubMed Central

    Zhen, Yu; Dong, Yuanlin; Wu, Xu; Xu, Zhipeng; Lu, Yan; Zhang, Yiying; Norton, David; Tian, Ming; Li, Shuren; Xie, Zhongcong

    2009-01-01

    Background Some anesthetics have been suggested to induce neurotoxicity including promotion of Alzheimer’s disease neuropathogenesis. Nitrous oxide and isoflurane are common anesthetics. Here, we set out to assess effects of nitrous oxide and/or isoflurane on apoptosis and β-amyloid (Aβ) levels in H4 human neuroglioma cells and primary neurons from naïve mice. Methods The cells or neurons were exposed to 70% nitrous oxide and/or 1% isoflurane for six hours. The cells or neurons and conditioned media were harvested at the end of the treatment. Caspase-3 activation, apoptosis, processing of amyloid precursor protein, and Aβ levels were determined. Results Treatment with a combination of 70% nitrous oxide and 1% isoflurane for six hours induced caspase-3 activation and apoptosis in H4 naïve cells and primary neurons from naïve mice. The 70% nitrous oxide plus 1% isoflurane, but neither alone, for six hours induced caspase-3 activation and apoptosis, and increased levels of β-site amyloid precursor protein-cleaving enzyme and Aβ in H4-amyloid precursor protein cells. In addition, the nitrous oxide plus isoflurane-induced Aβ generation was reduced by a broad caspase inhibitor Z-VAD. Finally, the nitrous oxide plus isoflurane-induced caspase-3 activation was attenuated by γ-secretase inhibitor L-685,458, but potentiated by exogenously added Aβ. Conclusion These results suggest that common anesthetics nitrous oxide plus isoflurane may promote neurotoxicity by inducing apoptosis and increasinglevels. The generated Aβ may further potentiate apoptosis to form another round of apoptosis and Aβ generation. More studies, especially the in vivo confirmation of these in vitro findings, are needed. PMID:19741497

  2. Salivary total sialic acid levels increase in breast cancer patients: a preliminary study.

    PubMed

    Oztürk, Leyla Koç; Emekli-Alturfan, Ebru; Kaşikci, Emel; Demir, Gokhan; Yarat, Aysen

    2011-09-01

    Breast cancer is the most common cancer in women living in the Western world, even though it occurs worldwide. Cancer and cancer therapy induce multiple oral complications including dental and periodontal disease. Saliva is a complex and dynamic biologic fluid, which reflects both oral and systemic changes. While saliva is easily accessible body fluid, there has been little effort to study its value in cancer diagnosis. Sialic acids (SA), the end moieties of the carbohydrate chains, are biologically important and essential for functions of glycoconjugates that are reported to be altered in both blood and saliva of various cancer patients. Increased sialylation has been shown to be a characteristic feature in cancer tissue and blood in breast cancer patients. However, there is no data about salivary SA in breast cancer. The aim of this study was to evaluate salivary total sialic acid (TSA) levels in breast cancer patients who were under chemotheraphy. The study included 15 breast cancer patients in different stages and 10 healthy individuals as age-matched controls. Unstimulated whole saliva was collected. Salivary total protein and SA levels were determined. Flow rate was calculated from salivary volume by the time of secretion. Salivary SA was significantly higher and total protein was lower in breast cancer patients compared to controls. It is concluded that sialylation may be increased in saliva of patients with breast cancer as the same way for cancer tissue and for blood . Increased salivary SA may therefore be useful as a non-invasive predictive marker for breast cancer patients and for the prevention and management of oral complications of cancer and cancer therapy to improve oral function and quality-of-life. The effects of different types of chemotherapies and different stages of the disease on salivary SA levels and salivary sialo-glycomic are worthy of being further investigated in breast cancer patients.

  3. High Levels of Heavy Metals Increase the Prevalence of Sarcopenia in the Elderly Population

    PubMed Central

    Yoo, Jun-Il; Lee, Young-Kyun; Koo, Kyung-Hoi

    2016-01-01

    Background Despite increasing concern regarding health problems as a result of environmental pollutants, no association of toxic heavy metals with sarcopenia has been demonstrated in the general population. We investigated the association of heavy metals, including lead, mercury and cadmium, with sarcopenia in the Korean population. Methods Participants included 344 males and 360 females older than 65 years based on data from the fourth and fifth Korea National Health and Nutritional Examination Surveys. Measurements of blood lead, mercury and cadmium levels were performed. To evaluate the cumulative effect of the three heavy metals, subjects were categorized into quartiles. Sarcopenia was defined according to the criteria for the Asia Working Group for Sarcopenia (AWGS) (SMI<5.4 kg/m2 in females and <7.0 kg/m2 in males). Results Of 704 elderly persons (344 in males and 360 in females), prevalences of sarcopenia were 26.7% (92/344) in male and 7.5% (27/360) in female. Mean serum levels of lead in sarcopenia group were significantly higher than non-sarcopenia males (P=0.03). After adjustment for confounding factors, odds ratio for sarcopenia were increased with concentration category of lead (P=0.005 and P<0.001), mercury (P=0.001 and P<0.001) and cadmium (P=0.010 and P<0.001) in males and females, respectively. Conclusions This study demonstrates that high levels of blood lead, mercury and cadmium increase the prevalence of sarcopenia in both genders of elderly populations. PMID:27294082

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

    PubMed Central

    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, 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. PMID:22489180

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

    PubMed

    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.

  6. Understanding dog owners' increased levels of physical activity: results from RESIDE.

    PubMed

    Cutt, Hayley; Giles-Corti, Billie; Knuiman, Matthew; Timperio, Anna; Bull, Fiona

    2008-01-01

    We examined the influence of dog ownership on physical activity, independent of demographic, intrapersonal, and perceived environmental factors, in a cross-sectional survey of 1813 adults. Although only 23% of the dog owners walked their dogs 5 or more times per week, the adjusted odds of achieving sufficient physical activity and walking were 57% to 77% higher among dog owners compared with those not owning dogs (P< .05). Dog ownership was independently associated with physical activity and walking. Actively encouraging more dog walking may increase community physical activity levels.

  7. Primary fibroblasts of NDUFS4(-/-) mice display increased ROS levels and aberrant mitochondrial morphology.

    PubMed

    Valsecchi, Federica; Grefte, Sander; Roestenberg, Peggy; Joosten-Wagenaars, Jori; Smeitink, Jan A M; Willems, Peter H G M; Koopman, Werner J H

    2013-09-01

    The human NDUFS4 gene encodes an accessory subunit of the first mitochondrial oxidative phosphorylation complex (CI) and, when mutated, is associated with progressive neurological disorders. Here we analyzed primary muscle and skin fibroblasts from NDUFS4(-/-) mice with respect to reactive oxygen species (ROS) levels and mitochondrial morphology. NDUFS4(-/-) fibroblasts displayed an inactive CI subcomplex on native gels but proliferated normally and showed no obvious signs of apoptosis. Oxidation of the ROS sensor hydroethidium was increased and mitochondria were less branched and/or shorter in NDUFS4(-/-) fibroblasts. We discuss the relevance of these findings with respect to previous results and therapy development.

  8. Increasing the Efficiency of Ideal Solar Cells by Photon Induced Transitions at Intermediate Levels

    SciTech Connect

    Luque, A.; Marti, A.

    1997-06-01

    Recent attempts have been made to increase the efficiency of solar cells by introducing an impurity level in the semiconductor band gap. We present an analysis of such a structure under ideal conditions. We prove that its efficiency can exceed not only the Shockley and Queisser efficiency for ideal solar cells but also that for ideal two-terminal tandem cells which use two semiconductors, as well as that predicted for ideal cells with quantum efficiency above one but less than two. {copyright} {ital 1997} {ital The American Physical Society}

  9. Ovarian tumors with elevated CA-125 levels and severe juvenile hypothyroidism: a need for increased awareness.

    PubMed

    Krishnamurthy, Sriram; Seth, Anju; Puri, Archana; Anand, Rama; Aneja, Satinder

    2010-06-01

    A 15-yr-old girl presented with bilateral gross ovarian tumors, clinical features of long-standing unrecognized hypothyroidism and markedly elevated CA-125 levels. Ovarian resection was avoided, as the presentation was consistent with the Van Wyk and Grumbach syndrome; and the patient was treated with replacement of thyroid hormone. Regression of the ovarian tumors occurred 6 months after initiation of the treatment. The authors emphasise the need for increased awareness and screening for hypothyroidism in patients with ovarian tumors, in order to prevent inadvertent operative interventions.

  10. In vivo levels of mitochondrial hydrogen peroxide increase with age in mtDNA mutator mice.

    PubMed

    Logan, Angela; Shabalina, Irina G; Prime, Tracy A; Rogatti, Sebastian; Kalinovich, Anastasia V; Hartley, Richard C; Budd, Ralph C; Cannon, Barbara; Murphy, Michael P

    2014-08-01

    In mtDNA mutator mice, mtDNA mutations accumulate leading to a rapidly aging phenotype. However, there is little evidence of oxidative damage to tissues, and when analyzed ex vivo, no change in production of the reactive oxygen species (ROS) superoxide and hydrogen peroxide by mitochondria has been reported, undermining the mitochondrial oxidative damage theory of aging. Paradoxically, interventions that decrease mitochondrial ROS levels in vivo delay onset of aging. To reconcile these findings, we used the mitochondria-targeted mass spectrometry probe MitoB to measure hydrogen peroxide within mitochondria of living mice. Mitochondrial hydrogen peroxide was the same in young mutator and control mice, but as the mutator mice aged, hydrogen peroxide increased. This suggests that the prolonged presence of mtDNA mutations in vivo increases hydrogen peroxide that contributes to an accelerated aging phenotype, perhaps through the activation of pro-apoptotic and pro-inflammatory redox signaling pathways.

  11. Energized by love: thinking about romantic relationships increases positive affect and blood glucose levels.

    PubMed

    Stanton, Sarah C E; Campbell, Lorne; Loving, Timothy J

    2014-10-01

    We assessed the impact of thinking of a current romantic partner on acute blood glucose responses and positive affect over a short period of time. Participants in romantic relationships were randomly assigned to reflect on their partner, an opposite-sex friend, or their morning routine. Blood glucose levels were assessed prior to reflection, as well as at 10 and 25 min postreflection. Results revealed that individuals in the routine and friend conditions exhibited a decline in glucose over time, whereas individuals in the partner condition did not exhibit this decline (rather, a slight increase) in glucose over time. Reported positive affect following reflection was positively associated with increases in glucose, but only for individuals who reflected on their partner, suggesting this physiological response reflects eustress. These findings add to the literature on eustress in relationships and have implications for relationship processes.

  12. Increased trefoil factor 2 levels in patients with chronic kidney disease

    PubMed Central

    Lebherz-Eichinger, Diana; Tudor, Bianca; Ankersmit, Hendrik J.; Reiter, Thomas; Haas, Martin; Einwallner, Elisa; Roth-Walter, Franziska; Krenn, Claus G.; Roth, Georg A.

    2017-01-01

    In chronically damaged tissue, trefoil factor family (TFF) peptides ensure epithelial protection and restitution. In chronic kidney disease (CKD), TFF1 and TFF2 are reported to be upregulated. Especially in the early phase, CKD is associated with silently ongoing renal damage and inflammation. Moreover, many patients are diagnosed late during disease progression. We therefore sought to investigate the potential of TFF2 as biomarker for CKD. We followed 118 patients suffering from predialysis CKD and 23 healthy volunteers. TFF2 concentrations were measured using ELISA. Our results showed, that median TFF2 serum levels were significantly higher in patients with later CKD stages as compared to healthy controls (p < 0.001) or early stages (p < 0.001). In patients with mid CKD stages TFF2 serum levels were significantly higher than in healthy controls (p = 0.002). Patients with early or mid CKD stages had significantly higher TFF2 urine concentrations than later CKD stages (p < 0.001 and p = 0.009, respectively). Fractional TFF2 excretion differed significantly between early CKD stages and healthy controls (p = 0.01). ROC curve showed that TFF2 levels can predict different CKD stages (AUC > 0.75). In conclusion, urine and serum TFF2 levels of CKD patients show a different profile dependent on CKD stages. Whereas TFF2 urine levels continuously decreased with disease progression, TFF2 serum concentrations progressively increased from the early to later CKD stages, indicating changes in renal function and offering the potential to examine the course of CKD. PMID:28355260

  13. Chronic mild stress increases alcohol intake in mice with low dopamine D2 receptor levels.

    PubMed

    Delis, Foteini; Thanos, Panayotis K; Rombola, Christina; Rosko, Lauren; Grandy, David; Wang, Gene-Jack; Volkow, Nora D

    2013-02-01

    Alcohol use disorders emerge from a complex interaction between environmental and genetic factors. Stress and dopamine D2 receptor levels (DRD2) have been shown to play a central role in alcoholism. To better understand the interactions between DRD2 and stress in ethanol intake behavior, we subjected Drd2 wild-type (+/+), heterozygous (+/-), and knockout (-/-) mice to 4 weeks of chronic mild stress (CMS) and to an ethanol two-bottle choice during CMS weeks 2-4. Prior to and at the end of the experiment, the animals were tested in the forced swim and open field tests. We measured ethanol intake and preference, immobility in the force swim test, and activity in the open field. We show that under no CMS, Drd2+/- and Drd2-/- mice had lower ethanol intake and preference compared with Drd2+/+. Exposure to CMS decreased ethanol intake and preference in Drd2+/+ and increased them in Drd2+/- and Drd2-/- mice. At baseline, Drd2+/- and Drd2-/- mice had significantly lower activity in the open field than Drd2+/+, whereas no genotype differences were observed in the forced swim test. Exposure to CMS increased immobility during the forced swim test in Drd2+/- mice, but not in Drd2+/+ or Drd2-/- mice, and ethanol intake reversed this behavior. No changes were observed in open field test measures. These findings suggest that in the presence of a stressful environment, low DRD2 levels are associated with increased ethanol intake and preference and that under this condition, increased ethanol consumption could be used as a strategy to alleviate negative mood.

  14. Loss of heterophylly in aquatic plants: not ABA-mediated stress but exogenous ABA treatment induces stomatal leaves in Potamogeton perfoliatus.

    PubMed

    Iida, Satoko; Ikeda, Miyuki; Amano, Momoe; Sakayama, Hidetoshi; Kadono, Yasuro; Kosuge, Keiko

    2016-09-01

    Heterophyllous aquatic plants produce aerial (i.e., floating and terrestrial) and submerged leaves-the latter lack stomata-while homophyllous plants contain only submerged leaves, and cannot survive on land. To identify whether differences in morphogenetic potential and/or physiological stress responses are responsible for variation in phenotypic plasticity between two plants types, responses to abscisic acid (ABA) and salinity stress were compared between the closely related, but ecologically diverse pondweeds, Potamogeton wrightii (heterophyllous) and P. perfoliatus (homophyllous). The ABA-treated (1 or 10 μM) P. wrightii plants exhibited heterophylly and produced leaves with stomata. The obligate submerged P. perfoliatus plants were able to produce stomata on their leaves, but there were no changes to leaf shape, and stomatal production occurred only at a high ABA concentration (10 μM). Under salinity stress conditions, only P. wrightii leaves formed stomata. Additionally, the expression of stress-responsive NCED genes, which encode a key enzyme in ABA biosynthesis, was consistently up-regulated in P. wrightii, but only temporarily in P. perfoliatus. The observed species-specific gene expression patterns may be responsible for the induction or suppression of stomatal production during exposure to salinity stress. These results suggest that the two Potamogeton species have an innate morphogenetic ability to form stomata, but the actual production of stomata depends on ABA-mediated stress responses specific to each species and habitat.

  15. Increased nitric oxide levels in cerebellum of cachectic rats with Walker 256 solid tumor.

    PubMed

    Fenner, Fa